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FFmpeg/libavfilter/vf_v360.c

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  1. /*

  2.  * Copyright (c) 2019 Eugene Lyapustin

  3.  *

  4.  * This file is part of FFmpeg.

  5.  *

  6.  * FFmpeg is free software; you can redistribute it and/or

  7.  * modify it under the terms of the GNU Lesser General Public

  8.  * License as published by the Free Software Foundation; either

  9.  * version 2.1 of the License, or (at your option) any later version.

  10.  *

  11.  * FFmpeg is distributed in the hope that it will be useful,

  12.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  13.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  14.  * Lesser General Public License for more details.

  15.  *

  16.  * You should have received a copy of the GNU Lesser General Public

  17.  * License along with FFmpeg; if not, write to the Free Software

  18.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  19.  */

  20. 

  21. /**

  22.  * @file

  23.  * 360 video conversion filter.

  24.  * Principle of operation:

  25.  *

  26.  * (for each pixel in output frame)

  27.  * 1) Calculate OpenGL-like coordinates (x, y, z) for pixel position (i, j)

  28.  * 2) Apply 360 operations (rotation, mirror) to (x, y, z)

  29.  * 3) Calculate pixel position (u, v) in input frame

  30.  * 4) Calculate interpolation window and weight for each pixel

  31.  *

  32.  * (for each frame)

  33.  * 5) Remap input frame to output frame using precalculated data

  34.  */

  35. 

  36. #include <math.h>

  37. 

  38. #include "libavutil/avassert.h"

  39. #include "libavutil/imgutils.h"

  40. #include "libavutil/pixdesc.h"

  41. #include "libavutil/opt.h"

  42. #include "avfilter.h"

  43. #include "formats.h"

  44. #include "internal.h"

  45. #include "video.h"

  46. #include "v360.h"

  47. 

  48. typedef struct ThreadData {

  49.     AVFrame *in;

  50.     AVFrame *out;

  51. } ThreadData;

  52. 

  53. #define OFFSET(x) offsetof(V360Context, x)

  54. #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM

  55. #define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM

  56. 

  57. static const AVOption v360_options[] = {

  58.     {     "input", "set input projection",              OFFSET(in), AV_OPT_TYPE_INT,    {.i64=EQUIRECTANGULAR}, 0,    NB_PROJECTIONS-1, FLAGS, "in" },

  59.     {         "e", "equirectangular",                            0, AV_OPT_TYPE_CONST,  {.i64=EQUIRECTANGULAR}, 0,                   0, FLAGS, "in" },

  60.     {  "equirect", "equirectangular",                            0, AV_OPT_TYPE_CONST,  {.i64=EQUIRECTANGULAR}, 0,                   0, FLAGS, "in" },

  61.     {      "c3x2", "cubemap 3x2",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_3_2},     0,                   0, FLAGS, "in" },

  62.     {      "c6x1", "cubemap 6x1",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_6_1},     0,                   0, FLAGS, "in" },

  63.     {       "eac", "equi-angular cubemap",                       0, AV_OPT_TYPE_CONST,  {.i64=EQUIANGULAR},     0,                   0, FLAGS, "in" },

  64.     {  "dfisheye", "dual fisheye",                               0, AV_OPT_TYPE_CONST,  {.i64=DUAL_FISHEYE},    0,                   0, FLAGS, "in" },

  65.     {      "flat", "regular video",                              0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "in" },

  66.     {"rectilinear", "regular video",                             0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "in" },

  67.     {  "gnomonic", "regular video",                              0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "in" },

  68.     {    "barrel", "barrel facebook's 360 format",               0, AV_OPT_TYPE_CONST,  {.i64=BARREL},          0,                   0, FLAGS, "in" },

  69.     {        "fb", "barrel facebook's 360 format",               0, AV_OPT_TYPE_CONST,  {.i64=BARREL},          0,                   0, FLAGS, "in" },

  70.     {      "c1x6", "cubemap 1x6",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_1_6},     0,                   0, FLAGS, "in" },

  71.     {        "sg", "stereographic",                              0, AV_OPT_TYPE_CONST,  {.i64=STEREOGRAPHIC},   0,                   0, FLAGS, "in" },

  72.     {  "mercator", "mercator",                                   0, AV_OPT_TYPE_CONST,  {.i64=MERCATOR},        0,                   0, FLAGS, "in" },

  73.     {      "ball", "ball",                                       0, AV_OPT_TYPE_CONST,  {.i64=BALL},            0,                   0, FLAGS, "in" },

  74.     {    "hammer", "hammer",                                     0, AV_OPT_TYPE_CONST,  {.i64=HAMMER},          0,                   0, FLAGS, "in" },

  75.     {"sinusoidal", "sinusoidal",                                 0, AV_OPT_TYPE_CONST,  {.i64=SINUSOIDAL},      0,                   0, FLAGS, "in" },

  76.     {   "fisheye", "fisheye",                                    0, AV_OPT_TYPE_CONST,  {.i64=FISHEYE},         0,                   0, FLAGS, "in" },

  77.     {"cylindrical", "cylindrical",                               0, AV_OPT_TYPE_CONST,  {.i64=CYLINDRICAL},     0,                   0, FLAGS, "in" },

  78.     {"tetrahedron", "tetrahedron",                               0, AV_OPT_TYPE_CONST,  {.i64=TETRAHEDRON},     0,                   0, FLAGS, "in" },

  79.     {"barrelsplit", "barrel split facebook's 360 format",        0, AV_OPT_TYPE_CONST,  {.i64=BARREL_SPLIT},    0,                   0, FLAGS, "in" },

  80.     {    "output", "set output projection",            OFFSET(out), AV_OPT_TYPE_INT,    {.i64=CUBEMAP_3_2},     0,    NB_PROJECTIONS-1, FLAGS, "out" },

  81.     {         "e", "equirectangular",                            0, AV_OPT_TYPE_CONST,  {.i64=EQUIRECTANGULAR}, 0,                   0, FLAGS, "out" },

  82.     {  "equirect", "equirectangular",                            0, AV_OPT_TYPE_CONST,  {.i64=EQUIRECTANGULAR}, 0,                   0, FLAGS, "out" },

  83.     {      "c3x2", "cubemap 3x2",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_3_2},     0,                   0, FLAGS, "out" },

  84.     {      "c6x1", "cubemap 6x1",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_6_1},     0,                   0, FLAGS, "out" },

  85.     {       "eac", "equi-angular cubemap",                       0, AV_OPT_TYPE_CONST,  {.i64=EQUIANGULAR},     0,                   0, FLAGS, "out" },

  86.     {  "dfisheye", "dual fisheye",                               0, AV_OPT_TYPE_CONST,  {.i64=DUAL_FISHEYE},    0,                   0, FLAGS, "out" },

  87.     {      "flat", "regular video",                              0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "out" },

  88.     {"rectilinear", "regular video",                             0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "out" },

  89.     {  "gnomonic", "regular video",                              0, AV_OPT_TYPE_CONST,  {.i64=FLAT},            0,                   0, FLAGS, "out" },

  90.     {    "barrel", "barrel facebook's 360 format",               0, AV_OPT_TYPE_CONST,  {.i64=BARREL},          0,                   0, FLAGS, "out" },

  91.     {        "fb", "barrel facebook's 360 format",               0, AV_OPT_TYPE_CONST,  {.i64=BARREL},          0,                   0, FLAGS, "out" },

  92.     {      "c1x6", "cubemap 1x6",                                0, AV_OPT_TYPE_CONST,  {.i64=CUBEMAP_1_6},     0,                   0, FLAGS, "out" },

  93.     {        "sg", "stereographic",                              0, AV_OPT_TYPE_CONST,  {.i64=STEREOGRAPHIC},   0,                   0, FLAGS, "out" },

  94.     {  "mercator", "mercator",                                   0, AV_OPT_TYPE_CONST,  {.i64=MERCATOR},        0,                   0, FLAGS, "out" },

  95.     {      "ball", "ball",                                       0, AV_OPT_TYPE_CONST,  {.i64=BALL},            0,                   0, FLAGS, "out" },

  96.     {    "hammer", "hammer",                                     0, AV_OPT_TYPE_CONST,  {.i64=HAMMER},          0,                   0, FLAGS, "out" },

  97.     {"sinusoidal", "sinusoidal",                                 0, AV_OPT_TYPE_CONST,  {.i64=SINUSOIDAL},      0,                   0, FLAGS, "out" },

  98.     {   "fisheye", "fisheye",                                    0, AV_OPT_TYPE_CONST,  {.i64=FISHEYE},         0,                   0, FLAGS, "out" },

  99.     {   "pannini", "pannini",                                    0, AV_OPT_TYPE_CONST,  {.i64=PANNINI},         0,                   0, FLAGS, "out" },

  100.     {"cylindrical", "cylindrical",                               0, AV_OPT_TYPE_CONST,  {.i64=CYLINDRICAL},     0,                   0, FLAGS, "out" },

  101.     {"perspective", "perspective",                               0, AV_OPT_TYPE_CONST,  {.i64=PERSPECTIVE},     0,                   0, FLAGS, "out" },

  102.     {"tetrahedron", "tetrahedron",                               0, AV_OPT_TYPE_CONST,  {.i64=TETRAHEDRON},     0,                   0, FLAGS, "out" },

  103.     {"barrelsplit", "barrel split facebook's 360 format",        0, AV_OPT_TYPE_CONST,  {.i64=BARREL_SPLIT},    0,                   0, FLAGS, "out" },

  104.     {    "interp", "set interpolation method",      OFFSET(interp), AV_OPT_TYPE_INT,    {.i64=BILINEAR},        0, NB_INTERP_METHODS-1, FLAGS, "interp" },

  105.     {      "near", "nearest neighbour",                          0, AV_OPT_TYPE_CONST,  {.i64=NEAREST},         0,                   0, FLAGS, "interp" },

  106.     {   "nearest", "nearest neighbour",                          0, AV_OPT_TYPE_CONST,  {.i64=NEAREST},         0,                   0, FLAGS, "interp" },

  107.     {      "line", "bilinear interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=BILINEAR},        0,                   0, FLAGS, "interp" },

  108.     {    "linear", "bilinear interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=BILINEAR},        0,                   0, FLAGS, "interp" },

  109.     {      "cube", "bicubic interpolation",                      0, AV_OPT_TYPE_CONST,  {.i64=BICUBIC},         0,                   0, FLAGS, "interp" },

  110.     {     "cubic", "bicubic interpolation",                      0, AV_OPT_TYPE_CONST,  {.i64=BICUBIC},         0,                   0, FLAGS, "interp" },

  111.     {      "lanc", "lanczos interpolation",                      0, AV_OPT_TYPE_CONST,  {.i64=LANCZOS},         0,                   0, FLAGS, "interp" },

  112.     {   "lanczos", "lanczos interpolation",                      0, AV_OPT_TYPE_CONST,  {.i64=LANCZOS},         0,                   0, FLAGS, "interp" },

  113.     {      "sp16", "spline16 interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=SPLINE16},        0,                   0, FLAGS, "interp" },

  114.     {  "spline16", "spline16 interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=SPLINE16},        0,                   0, FLAGS, "interp" },

  115.     {     "gauss", "gaussian interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=GAUSSIAN},        0,                   0, FLAGS, "interp" },

  116.     {  "gaussian", "gaussian interpolation",                     0, AV_OPT_TYPE_CONST,  {.i64=GAUSSIAN},        0,                   0, FLAGS, "interp" },

  117.     {         "w", "output width",                   OFFSET(width), AV_OPT_TYPE_INT,    {.i64=0},               0,           INT16_MAX, FLAGS, "w"},

  118.     {         "h", "output height",                 OFFSET(height), AV_OPT_TYPE_INT,    {.i64=0},               0,           INT16_MAX, FLAGS, "h"},

  119.     { "in_stereo", "input stereo format",        OFFSET(in_stereo), AV_OPT_TYPE_INT,    {.i64=STEREO_2D},       0,    NB_STEREO_FMTS-1, FLAGS, "stereo" },

  120.     {"out_stereo", "output stereo format",      OFFSET(out_stereo), AV_OPT_TYPE_INT,    {.i64=STEREO_2D},       0,    NB_STEREO_FMTS-1, FLAGS, "stereo" },

  121.     {        "2d", "2d mono",                                    0, AV_OPT_TYPE_CONST,  {.i64=STEREO_2D},       0,                   0, FLAGS, "stereo" },

  122.     {       "sbs", "side by side",                               0, AV_OPT_TYPE_CONST,  {.i64=STEREO_SBS},      0,                   0, FLAGS, "stereo" },

  123.     {        "tb", "top bottom",                                 0, AV_OPT_TYPE_CONST,  {.i64=STEREO_TB},       0,                   0, FLAGS, "stereo" },

  124.     { "in_forder", "input cubemap face order",   OFFSET(in_forder), AV_OPT_TYPE_STRING, {.str="rludfb"},        0,     NB_DIRECTIONS-1, FLAGS, "in_forder"},

  125.     {"out_forder", "output cubemap face order", OFFSET(out_forder), AV_OPT_TYPE_STRING, {.str="rludfb"},        0,     NB_DIRECTIONS-1, FLAGS, "out_forder"},

  126.     {   "in_frot", "input cubemap face rotation",  OFFSET(in_frot), AV_OPT_TYPE_STRING, {.str="000000"},        0,     NB_DIRECTIONS-1, FLAGS, "in_frot"},

  127.     {  "out_frot", "output cubemap face rotation",OFFSET(out_frot), AV_OPT_TYPE_STRING, {.str="000000"},        0,     NB_DIRECTIONS-1, FLAGS, "out_frot"},

  128.     {    "in_pad", "percent input cubemap pads",    OFFSET(in_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 1.f,TFLAGS, "in_pad"},

  129.     {   "out_pad", "percent output cubemap pads",  OFFSET(out_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 1.f,TFLAGS, "out_pad"},

  130.     {   "fin_pad", "fixed input cubemap pads",     OFFSET(fin_pad), AV_OPT_TYPE_INT,    {.i64=0},               0,                 100,TFLAGS, "fin_pad"},

  131.     {  "fout_pad", "fixed output cubemap pads",   OFFSET(fout_pad), AV_OPT_TYPE_INT,    {.i64=0},               0,                 100,TFLAGS, "fout_pad"},

  132.     {       "yaw", "yaw rotation",                     OFFSET(yaw), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},        -180.f,               180.f,TFLAGS, "yaw"},

  133.     {     "pitch", "pitch rotation",                 OFFSET(pitch), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},        -180.f,               180.f,TFLAGS, "pitch"},

  134.     {      "roll", "roll rotation",                   OFFSET(roll), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},        -180.f,               180.f,TFLAGS, "roll"},

  135.     {    "rorder", "rotation order",                OFFSET(rorder), AV_OPT_TYPE_STRING, {.str="ypr"},           0,                   0,TFLAGS, "rorder"},

  136.     {     "h_fov", "horizontal field of view",       OFFSET(h_fov), AV_OPT_TYPE_FLOAT,  {.dbl=90.f},     0.00001f,               360.f,TFLAGS, "h_fov"},

  137.     {     "v_fov", "vertical field of view",         OFFSET(v_fov), AV_OPT_TYPE_FLOAT,  {.dbl=45.f},     0.00001f,               360.f,TFLAGS, "v_fov"},

  138.     {     "d_fov", "diagonal field of view",         OFFSET(d_fov), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,               360.f,TFLAGS, "d_fov"},

  139.     {    "h_flip", "flip out video horizontally",   OFFSET(h_flip), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1,TFLAGS, "h_flip"},

  140.     {    "v_flip", "flip out video vertically",     OFFSET(v_flip), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1,TFLAGS, "v_flip"},

  141.     {    "d_flip", "flip out video indepth",        OFFSET(d_flip), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1,TFLAGS, "d_flip"},

  142.     {   "ih_flip", "flip in video horizontally",   OFFSET(ih_flip), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1,TFLAGS, "ih_flip"},

  143.     {   "iv_flip", "flip in video vertically",     OFFSET(iv_flip), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1,TFLAGS, "iv_flip"},

  144.     {  "in_trans", "transpose video input",   OFFSET(in_transpose), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1, FLAGS, "in_transpose"},

  145.     { "out_trans", "transpose video output", OFFSET(out_transpose), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1, FLAGS, "out_transpose"},

  146.     {    "ih_fov", "input horizontal field of view",OFFSET(ih_fov), AV_OPT_TYPE_FLOAT,  {.dbl=90.f},     0.00001f,               360.f,TFLAGS, "ih_fov"},

  147.     {    "iv_fov", "input vertical field of view",  OFFSET(iv_fov), AV_OPT_TYPE_FLOAT,  {.dbl=45.f},     0.00001f,               360.f,TFLAGS, "iv_fov"},

  148.     {    "id_fov", "input diagonal field of view",  OFFSET(id_fov), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,               360.f,TFLAGS, "id_fov"},

  149.     {"alpha_mask", "build mask in alpha plane",      OFFSET(alpha), AV_OPT_TYPE_BOOL,   {.i64=0},               0,                   1, FLAGS, "alpha"},

  150.     { NULL }

  151. };

  152. 

  153. AVFILTER_DEFINE_CLASS(v360);

  154. 

  155. static int query_formats(AVFilterContext *ctx)

  156. {

  157.     V360Context *s = ctx->priv;

  158.     static const enum AVPixelFormat pix_fmts[] = {

  159.         // YUVA444

  160.         AV_PIX_FMT_YUVA444P,   AV_PIX_FMT_YUVA444P9,

  161.         AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12,

  162.         AV_PIX_FMT_YUVA444P16,

  163. 

  164.         // YUVA422

  165.         AV_PIX_FMT_YUVA422P,   AV_PIX_FMT_YUVA422P9,

  166.         AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12,

  167.         AV_PIX_FMT_YUVA422P16,

  168. 

  169.         // YUVA420

  170.         AV_PIX_FMT_YUVA420P,   AV_PIX_FMT_YUVA420P9,

  171.         AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,

  172. 

  173.         // YUVJ

  174.         AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,

  175.         AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,

  176.         AV_PIX_FMT_YUVJ411P,

  177. 

  178.         // YUV444

  179.         AV_PIX_FMT_YUV444P,   AV_PIX_FMT_YUV444P9,

  180.         AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV444P12,

  181.         AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV444P16,

  182. 

  183.         // YUV440

  184.         AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV440P10,

  185.         AV_PIX_FMT_YUV440P12,

  186. 

  187.         // YUV422

  188.         AV_PIX_FMT_YUV422P,   AV_PIX_FMT_YUV422P9,

  189.         AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV422P12,

  190.         AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV422P16,

  191. 

  192.         // YUV420

  193.         AV_PIX_FMT_YUV420P,   AV_PIX_FMT_YUV420P9,

  194.         AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV420P12,

  195.         AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV420P16,

  196. 

  197.         // YUV411

  198.         AV_PIX_FMT_YUV411P,

  199. 

  200.         // YUV410

  201.         AV_PIX_FMT_YUV410P,

  202. 

  203.         // GBR

  204.         AV_PIX_FMT_GBRP,   AV_PIX_FMT_GBRP9,

  205.         AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRP12,

  206.         AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,

  207. 

  208.         // GBRA

  209.         AV_PIX_FMT_GBRAP,   AV_PIX_FMT_GBRAP10,

  210.         AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,

  211. 

  212.         // GRAY

  213.         AV_PIX_FMT_GRAY8,  AV_PIX_FMT_GRAY9,

  214.         AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12,

  215.         AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16,

  216. 

  217.         AV_PIX_FMT_NONE

  218.     };

  219.     static const enum AVPixelFormat alpha_pix_fmts[] = {

  220.         AV_PIX_FMT_YUVA444P,   AV_PIX_FMT_YUVA444P9,

  221.         AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12,

  222.         AV_PIX_FMT_YUVA444P16,

  223.         AV_PIX_FMT_YUVA422P,   AV_PIX_FMT_YUVA422P9,

  224.         AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12,

  225.         AV_PIX_FMT_YUVA422P16,

  226.         AV_PIX_FMT_YUVA420P,   AV_PIX_FMT_YUVA420P9,

  227.         AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,

  228.         AV_PIX_FMT_GBRAP,   AV_PIX_FMT_GBRAP10,

  229.         AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,

  230.         AV_PIX_FMT_NONE

  231.     };

  232. 

  233.     AVFilterFormats *fmts_list = ff_make_format_list(s->alpha ? alpha_pix_fmts : pix_fmts);

  234.     if (!fmts_list)

  235.         return AVERROR(ENOMEM);

  236.     return ff_set_common_formats(ctx, fmts_list);

  237. }

  238. 

  239. #define DEFINE_REMAP1_LINE(bits, div)                                                    \

  240. static void remap1_##bits##bit_line_c(uint8_t *dst, int width, const uint8_t *const src, \

  241.                                       ptrdiff_t in_linesize,                             \

  242.                                       const int16_t *const u, const int16_t *const v,    \

  243.                                       const int16_t *const ker)                          \

  244. {                                                                                        \

  245.     const uint##bits##_t *const s = (const uint##bits##_t *const)src;                    \

  246.     uint##bits##_t *d = (uint##bits##_t *)dst;                                           \

  247.                                                                                          \

  248.     in_linesize /= div;                                                                  \

  249.                                                                                          \

  250.     for (int x = 0; x < width; x++)                                                      \

  251.         d[x] = s[v[x] * in_linesize + u[x]];                                             \

  252. }

  253. 

  254. DEFINE_REMAP1_LINE( 8, 1)

  255. DEFINE_REMAP1_LINE(16, 2)

  256. 

  257. /**

  258.  * Generate remapping function with a given window size and pixel depth.

  259.  *

  260.  * @param ws size of interpolation window

  261.  * @param bits number of bits per pixel

  262.  */

  263. #define DEFINE_REMAP(ws, bits)                                                                             \

  264. static int remap##ws##_##bits##bit_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)          \

  265. {                                                                                                          \

  266.     ThreadData *td = arg;                                                                                  \

  267.     const V360Context *s = ctx->priv;                                                                      \

  268.     const AVFrame *in = td->in;                                                                            \

  269.     AVFrame *out = td->out;                                                                                \

  270.                                                                                                            \

  271.     for (int stereo = 0; stereo < 1 + s->out_stereo > STEREO_2D; stereo++) {                               \

  272.         for (int plane = 0; plane < s->nb_planes; plane++) {                                               \

  273.             const unsigned map = s->map[plane];                                                            \

  274.             const int in_linesize  = in->linesize[plane];                                                  \

  275.             const int out_linesize = out->linesize[plane];                                                 \

  276.             const int uv_linesize = s->uv_linesize[plane];                                                 \

  277.             const int in_offset_w = stereo ? s->in_offset_w[plane] : 0;                                    \

  278.             const int in_offset_h = stereo ? s->in_offset_h[plane] : 0;                                    \

  279.             const int out_offset_w = stereo ? s->out_offset_w[plane] : 0;                                  \

  280.             const int out_offset_h = stereo ? s->out_offset_h[plane] : 0;                                  \

  281.             const uint8_t *const src = in->data[plane] +                                                   \

  282.                                                    in_offset_h * in_linesize + in_offset_w * (bits >> 3);  \

  283.             uint8_t *dst = out->data[plane] + out_offset_h * out_linesize + out_offset_w * (bits >> 3);    \

  284.             const uint8_t *mask = plane == 3 ? s->mask : NULL;                                             \

  285.             const int width = s->pr_width[plane];                                                          \

  286.             const int height = s->pr_height[plane];                                                        \

  287.                                                                                                            \

  288.             const int slice_start = (height *  jobnr     ) / nb_jobs;                                      \

  289.             const int slice_end   = (height * (jobnr + 1)) / nb_jobs;                                      \

  290.                                                                                                            \

  291.             for (int y = slice_start; y < slice_end && !mask; y++) {                                       \

  292.                 const int16_t *const u = s->u[map] + y * uv_linesize * ws * ws;                            \

  293.                 const int16_t *const v = s->v[map] + y * uv_linesize * ws * ws;                            \

  294.                 const int16_t *const ker = s->ker[map] + y * uv_linesize * ws * ws;                        \

  295.                                                                                                            \

  296.                 s->remap_line(dst + y * out_linesize, width, src, in_linesize, u, v, ker);                 \

  297.             }                                                                                              \

  298.                                                                                                            \

  299.             for (int y = slice_start; y < slice_end && mask; y++) {                                        \

  300.                 memcpy(dst + y * out_linesize, mask + y * width * (bits >> 3), width * (bits >> 3));       \

  301.             }                                                                                              \

  302.         }                                                                                                  \

  303.     }                                                                                                      \

  304.                                                                                                            \

  305.     return 0;                                                                                              \

  306. }

  307. 

  308. DEFINE_REMAP(1,  8)

  309. DEFINE_REMAP(2,  8)

  310. DEFINE_REMAP(4,  8)

  311. DEFINE_REMAP(1, 16)

  312. DEFINE_REMAP(2, 16)

  313. DEFINE_REMAP(4, 16)

  314. 

  315. #define DEFINE_REMAP_LINE(ws, bits, div)                                                      \

  316. static void remap##ws##_##bits##bit_line_c(uint8_t *dst, int width, const uint8_t *const src, \

  317.                                            ptrdiff_t in_linesize,                             \

  318.                                            const int16_t *const u, const int16_t *const v,    \

  319.                                            const int16_t *const ker)                          \

  320. {                                                                                             \

  321.     const uint##bits##_t *const s = (const uint##bits##_t *const)src;                         \

  322.     uint##bits##_t *d = (uint##bits##_t *)dst;                                                \

  323.                                                                                               \

  324.     in_linesize /= div;                                                                       \

  325.                                                                                               \

  326.     for (int x = 0; x < width; x++) {                                                         \

  327.         const int16_t *const uu = u + x * ws * ws;                                            \

  328.         const int16_t *const vv = v + x * ws * ws;                                            \

  329.         const int16_t *const kker = ker + x * ws * ws;                                        \

  330.         int tmp = 0;                                                                          \

  331.                                                                                               \

  332.         for (int i = 0; i < ws; i++) {                                                        \

  333.             for (int j = 0; j < ws; j++) {                                                    \

  334.                 tmp += kker[i * ws + j] * s[vv[i * ws + j] * in_linesize + uu[i * ws + j]];   \

  335.             }                                                                                 \

  336.         }                                                                                     \

  337.                                                                                               \

  338.         d[x] = av_clip_uint##bits(tmp >> 14);                                                 \

  339.     }                                                                                         \

  340. }

  341. 

  342. DEFINE_REMAP_LINE(2,  8, 1)

  343. DEFINE_REMAP_LINE(4,  8, 1)

  344. DEFINE_REMAP_LINE(2, 16, 2)

  345. DEFINE_REMAP_LINE(4, 16, 2)

  346. 

  347. void ff_v360_init(V360Context *s, int depth)

  348. {

  349.     switch (s->interp) {

  350.     case NEAREST:

  351.         s->remap_line = depth <= 8 ? remap1_8bit_line_c : remap1_16bit_line_c;

  352.         break;

  353.     case BILINEAR:

  354.         s->remap_line = depth <= 8 ? remap2_8bit_line_c : remap2_16bit_line_c;

  355.         break;

  356.     case BICUBIC:

  357.     case LANCZOS:

  358.     case SPLINE16:

  359.     case GAUSSIAN:

  360.         s->remap_line = depth <= 8 ? remap4_8bit_line_c : remap4_16bit_line_c;

  361.         break;

  362.     }

  363. 

  364.     if (ARCH_X86)

  365.         ff_v360_init_x86(s, depth);

  366. }

  367. 

  368. /**

  369.  * Save nearest pixel coordinates for remapping.

  370.  *

  371.  * @param du horizontal relative coordinate

  372.  * @param dv vertical relative coordinate

  373.  * @param rmap calculated 4x4 window

  374.  * @param u u remap data

  375.  * @param v v remap data

  376.  * @param ker ker remap data

  377.  */

  378. static void nearest_kernel(float du, float dv, const XYRemap *rmap,

  379.                            int16_t *u, int16_t *v, int16_t *ker)

  380. {

  381.     const int i = lrintf(dv) + 1;

  382.     const int j = lrintf(du) + 1;

  383. 

  384.     u[0] = rmap->u[i][j];

  385.     v[0] = rmap->v[i][j];

  386. }

  387. 

  388. /**

  389.  * Calculate kernel for bilinear interpolation.

  390.  *

  391.  * @param du horizontal relative coordinate

  392.  * @param dv vertical relative coordinate

  393.  * @param rmap calculated 4x4 window

  394.  * @param u u remap data

  395.  * @param v v remap data

  396.  * @param ker ker remap data

  397.  */

  398. static void bilinear_kernel(float du, float dv, const XYRemap *rmap,

  399.                             int16_t *u, int16_t *v, int16_t *ker)

  400. {

  401.     for (int i = 0; i < 2; i++) {

  402.         for (int j = 0; j < 2; j++) {

  403.             u[i * 2 + j] = rmap->u[i + 1][j + 1];

  404.             v[i * 2 + j] = rmap->v[i + 1][j + 1];

  405.         }

  406.     }

  407. 

  408.     ker[0] = lrintf((1.f - du) * (1.f - dv) * 16385.f);

  409.     ker[1] = lrintf(       du  * (1.f - dv) * 16385.f);

  410.     ker[2] = lrintf((1.f - du) *        dv  * 16385.f);

  411.     ker[3] = lrintf(       du  *        dv  * 16385.f);

  412. }

  413. 

  414. /**

  415.  * Calculate 1-dimensional cubic coefficients.

  416.  *

  417.  * @param t relative coordinate

  418.  * @param coeffs coefficients

  419.  */

  420. static inline void calculate_bicubic_coeffs(float t, float *coeffs)

  421. {

  422.     const float tt  = t * t;

  423.     const float ttt = t * t * t;

  424. 

  425.     coeffs[0] =     - t / 3.f + tt / 2.f - ttt / 6.f;

  426.     coeffs[1] = 1.f - t / 2.f - tt       + ttt / 2.f;

  427.     coeffs[2] =       t       + tt / 2.f - ttt / 2.f;

  428.     coeffs[3] =     - t / 6.f            + ttt / 6.f;

  429. }

  430. 

  431. /**

  432.  * Calculate kernel for bicubic interpolation.

  433.  *

  434.  * @param du horizontal relative coordinate

  435.  * @param dv vertical relative coordinate

  436.  * @param rmap calculated 4x4 window

  437.  * @param u u remap data

  438.  * @param v v remap data

  439.  * @param ker ker remap data

  440.  */

  441. static void bicubic_kernel(float du, float dv, const XYRemap *rmap,

  442.                            int16_t *u, int16_t *v, int16_t *ker)

  443. {

  444.     float du_coeffs[4];

  445.     float dv_coeffs[4];

  446. 

  447.     calculate_bicubic_coeffs(du, du_coeffs);

  448.     calculate_bicubic_coeffs(dv, dv_coeffs);

  449. 

  450.     for (int i = 0; i < 4; i++) {

  451.         for (int j = 0; j < 4; j++) {

  452.             u[i * 4 + j] = rmap->u[i][j];

  453.             v[i * 4 + j] = rmap->v[i][j];

  454.             ker[i * 4 + j] = lrintf(du_coeffs[j] * dv_coeffs[i] * 16385.f);

  455.         }

  456.     }

  457. }

  458. 

  459. /**

  460.  * Calculate 1-dimensional lanczos coefficients.

  461.  *

  462.  * @param t relative coordinate

  463.  * @param coeffs coefficients

  464.  */

  465. static inline void calculate_lanczos_coeffs(float t, float *coeffs)

  466. {

  467.     float sum = 0.f;

  468. 

  469.     for (int i = 0; i < 4; i++) {

  470.         const float x = M_PI * (t - i + 1);

  471.         if (x == 0.f) {

  472.             coeffs[i] = 1.f;

  473.         } else {

  474.             coeffs[i] = sinf(x) * sinf(x / 2.f) / (x * x / 2.f);

  475.         }

  476.         sum += coeffs[i];

  477.     }

  478. 

  479.     for (int i = 0; i < 4; i++) {

  480.         coeffs[i] /= sum;

  481.     }

  482. }

  483. 

  484. /**

  485.  * Calculate kernel for lanczos interpolation.

  486.  *

  487.  * @param du horizontal relative coordinate

  488.  * @param dv vertical relative coordinate

  489.  * @param rmap calculated 4x4 window

  490.  * @param u u remap data

  491.  * @param v v remap data

  492.  * @param ker ker remap data

  493.  */

  494. static void lanczos_kernel(float du, float dv, const XYRemap *rmap,

  495.                            int16_t *u, int16_t *v, int16_t *ker)

  496. {

  497.     float du_coeffs[4];

  498.     float dv_coeffs[4];

  499. 

  500.     calculate_lanczos_coeffs(du, du_coeffs);

  501.     calculate_lanczos_coeffs(dv, dv_coeffs);

  502. 

  503.     for (int i = 0; i < 4; i++) {

  504.         for (int j = 0; j < 4; j++) {

  505.             u[i * 4 + j] = rmap->u[i][j];

  506.             v[i * 4 + j] = rmap->v[i][j];

  507.             ker[i * 4 + j] = lrintf(du_coeffs[j] * dv_coeffs[i] * 16385.f);

  508.         }

  509.     }

  510. }

  511. 

  512. /**

  513.  * Calculate 1-dimensional spline16 coefficients.

  514.  *

  515.  * @param t relative coordinate

  516.  * @param coeffs coefficients

  517.  */

  518. static void calculate_spline16_coeffs(float t, float *coeffs)

  519. {

  520.     coeffs[0] = ((-1.f / 3.f * t + 0.8f) * t - 7.f / 15.f) * t;

  521.     coeffs[1] = ((t - 9.f / 5.f) * t - 0.2f) * t + 1.f;

  522.     coeffs[2] = ((6.f / 5.f - t) * t + 0.8f) * t;

  523.     coeffs[3] = ((1.f / 3.f * t - 0.2f) * t - 2.f / 15.f) * t;

  524. }

  525. 

  526. /**

  527.  * Calculate kernel for spline16 interpolation.

  528.  *

  529.  * @param du horizontal relative coordinate

  530.  * @param dv vertical relative coordinate

  531.  * @param rmap calculated 4x4 window

  532.  * @param u u remap data

  533.  * @param v v remap data

  534.  * @param ker ker remap data

  535.  */

  536. static void spline16_kernel(float du, float dv, const XYRemap *rmap,

  537.                             int16_t *u, int16_t *v, int16_t *ker)

  538. {

  539.     float du_coeffs[4];

  540.     float dv_coeffs[4];

  541. 

  542.     calculate_spline16_coeffs(du, du_coeffs);

  543.     calculate_spline16_coeffs(dv, dv_coeffs);

  544. 

  545.     for (int i = 0; i < 4; i++) {

  546.         for (int j = 0; j < 4; j++) {

  547.             u[i * 4 + j] = rmap->u[i][j];

  548.             v[i * 4 + j] = rmap->v[i][j];

  549.             ker[i * 4 + j] = lrintf(du_coeffs[j] * dv_coeffs[i] * 16385.f);

  550.         }

  551.     }

  552. }

  553. 

  554. /**

  555.  * Calculate 1-dimensional gaussian coefficients.

  556.  *

  557.  * @param t relative coordinate

  558.  * @param coeffs coefficients

  559.  */

  560. static void calculate_gaussian_coeffs(float t, float *coeffs)

  561. {

  562.     float sum = 0.f;

  563. 

  564.     for (int i = 0; i < 4; i++) {

  565.         const float x = t - (i - 1);

  566.         if (x == 0.f) {

  567.             coeffs[i] = 1.f;

  568.         } else {

  569.             coeffs[i] = expf(-2.f * x * x) * expf(-x * x / 2.f);

  570.         }

  571.         sum += coeffs[i];

  572.     }

  573. 

  574.     for (int i = 0; i < 4; i++) {

  575.         coeffs[i] /= sum;

  576.     }

  577. }

  578. 

  579. /**

  580.  * Calculate kernel for gaussian interpolation.

  581.  *

  582.  * @param du horizontal relative coordinate

  583.  * @param dv vertical relative coordinate

  584.  * @param rmap calculated 4x4 window

  585.  * @param u u remap data

  586.  * @param v v remap data

  587.  * @param ker ker remap data

  588.  */

  589. static void gaussian_kernel(float du, float dv, const XYRemap *rmap,

  590.                             int16_t *u, int16_t *v, int16_t *ker)

  591. {

  592.     float du_coeffs[4];

  593.     float dv_coeffs[4];

  594. 

  595.     calculate_gaussian_coeffs(du, du_coeffs);

  596.     calculate_gaussian_coeffs(dv, dv_coeffs);

  597. 

  598.     for (int i = 0; i < 4; i++) {

  599.         for (int j = 0; j < 4; j++) {

  600.             u[i * 4 + j] = rmap->u[i][j];

  601.             v[i * 4 + j] = rmap->v[i][j];

  602.             ker[i * 4 + j] = lrintf(du_coeffs[j] * dv_coeffs[i] * 16385.f);

  603.         }

  604.     }

  605. }

  606. 

  607. /**

  608.  * Modulo operation with only positive remainders.

  609.  *

  610.  * @param a dividend

  611.  * @param b divisor

  612.  *

  613.  * @return positive remainder of (a / b)

  614.  */

  615. static inline int mod(int a, int b)

  616. {

  617.     const int res = a % b;

  618.     if (res < 0) {

  619.         return res + b;

  620.     } else {

  621.         return res;

  622.     }

  623. }

  624. 

  625. /**

  626.  * Reflect y operation.

  627.  *

  628.  * @param y input vertical position

  629.  * @param h input height

  630.  */

  631. static inline int reflecty(int y, int h)

  632. {

  633.     if (y < 0) {

  634.         return -y;

  635.     } else if (y >= h) {

  636.         return 2 * h - 1 - y;

  637.     }

  638. 

  639.     return y;

  640. }

  641. 

  642. /**

  643.  * Reflect x operation for equirect.

  644.  *

  645.  * @param x input horizontal position

  646.  * @param y input vertical position

  647.  * @param w input width

  648.  * @param h input height

  649.  */

  650. static inline int ereflectx(int x, int y, int w, int h)

  651. {

  652.     if (y < 0 || y >= h)

  653.         x += w / 2;

  654. 

  655.     return mod(x, w);

  656. }

  657. 

  658. /**

  659.  * Reflect x operation.

  660.  *

  661.  * @param x input horizontal position

  662.  * @param y input vertical position

  663.  * @param w input width

  664.  * @param h input height

  665.  */

  666. static inline int reflectx(int x, int y, int w, int h)

  667. {

  668.     if (y < 0 || y >= h)

  669.         return w - 1 - x;

  670. 

  671.     return mod(x, w);

  672. }

  673. 

  674. /**

  675.  * Convert char to corresponding direction.

  676.  * Used for cubemap options.

  677.  */

  678. static int get_direction(char c)

  679. {

  680.     switch (c) {

  681.     case 'r':

  682.         return RIGHT;

  683.     case 'l':

  684.         return LEFT;

  685.     case 'u':

  686.         return UP;

  687.     case 'd':

  688.         return DOWN;

  689.     case 'f':

  690.         return FRONT;

  691.     case 'b':

  692.         return BACK;

  693.     default:

  694.         return -1;

  695.     }

  696. }

  697. 

  698. /**

  699.  * Convert char to corresponding rotation angle.

  700.  * Used for cubemap options.

  701.  */

  702. static int get_rotation(char c)

  703. {

  704.     switch (c) {

  705.     case '0':

  706.         return ROT_0;

  707.     case '1':

  708.         return ROT_90;

  709.     case '2':

  710.         return ROT_180;

  711.     case '3':

  712.         return ROT_270;

  713.     default:

  714.         return -1;

  715.     }

  716. }

  717. 

  718. /**

  719.  * Convert char to corresponding rotation order.

  720.  */

  721. static int get_rorder(char c)

  722. {

  723.     switch (c) {

  724.     case 'Y':

  725.     case 'y':

  726.         return YAW;

  727.     case 'P':

  728.     case 'p':

  729.         return PITCH;

  730.     case 'R':

  731.     case 'r':

  732.         return ROLL;

  733.     default:

  734.         return -1;

  735.     }

  736. }

  737. 

  738. /**

  739.  * Prepare data for processing cubemap input format.

  740.  *

  741.  * @param ctx filter context

  742.  *

  743.  * @return error code

  744.  */

  745. static int prepare_cube_in(AVFilterContext *ctx)

  746. {

  747.     V360Context *s = ctx->priv;

  748. 

  749.     for (int face = 0; face < NB_FACES; face++) {

  750.         const char c = s->in_forder[face];

  751.         int direction;

  752. 

  753.         if (c == '\0') {

  754.             av_log(ctx, AV_LOG_ERROR,

  755.                    "Incomplete in_forder option. Direction for all 6 faces should be specified.\n");

  756.             return AVERROR(EINVAL);

  757.         }

  758. 

  759.         direction = get_direction(c);

  760.         if (direction == -1) {

  761.             av_log(ctx, AV_LOG_ERROR,

  762.                    "Incorrect direction symbol '%c' in in_forder option.\n", c);

  763.             return AVERROR(EINVAL);

  764.         }

  765. 

  766.         s->in_cubemap_face_order[direction] = face;

  767.     }

  768. 

  769.     for (int face = 0; face < NB_FACES; face++) {

  770.         const char c = s->in_frot[face];

  771.         int rotation;

  772. 

  773.         if (c == '\0') {

  774.             av_log(ctx, AV_LOG_ERROR,

  775.                    "Incomplete in_frot option. Rotation for all 6 faces should be specified.\n");

  776.             return AVERROR(EINVAL);

  777.         }

  778. 

  779.         rotation = get_rotation(c);

  780.         if (rotation == -1) {

  781.             av_log(ctx, AV_LOG_ERROR,

  782.                    "Incorrect rotation symbol '%c' in in_frot option.\n", c);

  783.             return AVERROR(EINVAL);

  784.         }

  785. 

  786.         s->in_cubemap_face_rotation[face] = rotation;

  787.     }

  788. 

  789.     return 0;

  790. }

  791. 

  792. /**

  793.  * Prepare data for processing cubemap output format.

  794.  *

  795.  * @param ctx filter context

  796.  *

  797.  * @return error code

  798.  */

  799. static int prepare_cube_out(AVFilterContext *ctx)

  800. {

  801.     V360Context *s = ctx->priv;

  802. 

  803.     for (int face = 0; face < NB_FACES; face++) {

  804.         const char c = s->out_forder[face];

  805.         int direction;

  806. 

  807.         if (c == '\0') {

  808.             av_log(ctx, AV_LOG_ERROR,

  809.                    "Incomplete out_forder option. Direction for all 6 faces should be specified.\n");

  810.             return AVERROR(EINVAL);

  811.         }

  812. 

  813.         direction = get_direction(c);

  814.         if (direction == -1) {

  815.             av_log(ctx, AV_LOG_ERROR,

  816.                    "Incorrect direction symbol '%c' in out_forder option.\n", c);

  817.             return AVERROR(EINVAL);

  818.         }

  819. 

  820.         s->out_cubemap_direction_order[face] = direction;

  821.     }

  822. 

  823.     for (int face = 0; face < NB_FACES; face++) {

  824.         const char c = s->out_frot[face];

  825.         int rotation;

  826. 

  827.         if (c == '\0') {

  828.             av_log(ctx, AV_LOG_ERROR,

  829.                    "Incomplete out_frot option. Rotation for all 6 faces should be specified.\n");

  830.             return AVERROR(EINVAL);

  831.         }

  832. 

  833.         rotation = get_rotation(c);

  834.         if (rotation == -1) {

  835.             av_log(ctx, AV_LOG_ERROR,

  836.                    "Incorrect rotation symbol '%c' in out_frot option.\n", c);

  837.             return AVERROR(EINVAL);

  838.         }

  839. 

  840.         s->out_cubemap_face_rotation[face] = rotation;

  841.     }

  842. 

  843.     return 0;

  844. }

  845. 

  846. static inline void rotate_cube_face(float *uf, float *vf, int rotation)

  847. {

  848.     float tmp;

  849. 

  850.     switch (rotation) {

  851.     case ROT_0:

  852.         break;

  853.     case ROT_90:

  854.         tmp =  *uf;

  855.         *uf = -*vf;

  856.         *vf =  tmp;

  857.         break;

  858.     case ROT_180:

  859.         *uf = -*uf;

  860.         *vf = -*vf;

  861.         break;

  862.     case ROT_270:

  863.         tmp = -*uf;

  864.         *uf =  *vf;

  865.         *vf =  tmp;

  866.         break;

  867.     default:

  868.         av_assert0(0);

  869.     }

  870. }

  871. 

  872. static inline void rotate_cube_face_inverse(float *uf, float *vf, int rotation)

  873. {

  874.     float tmp;

  875. 

  876.     switch (rotation) {

  877.     case ROT_0:

  878.         break;

  879.     case ROT_90:

  880.         tmp = -*uf;

  881.         *uf =  *vf;

  882.         *vf =  tmp;

  883.         break;

  884.     case ROT_180:

  885.         *uf = -*uf;

  886.         *vf = -*vf;

  887.         break;

  888.     case ROT_270:

  889.         tmp =  *uf;

  890.         *uf = -*vf;

  891.         *vf =  tmp;

  892.         break;

  893.     default:

  894.         av_assert0(0);

  895.     }

  896. }

  897. 

  898. /**

  899.  * Normalize vector.

  900.  *

  901.  * @param vec vector

  902.  */

  903. static void normalize_vector(float *vec)

  904. {

  905.     const float norm = sqrtf(vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2]);

  906. 

  907.     vec[0] /= norm;

  908.     vec[1] /= norm;

  909.     vec[2] /= norm;

  910. }

  911. 

  912. /**

  913.  * Calculate 3D coordinates on sphere for corresponding cubemap position.

  914.  * Common operation for every cubemap.

  915.  *

  916.  * @param s filter private context

  917.  * @param uf horizontal cubemap coordinate [0, 1)

  918.  * @param vf vertical cubemap coordinate [0, 1)

  919.  * @param face face of cubemap

  920.  * @param vec coordinates on sphere

  921.  * @param scalew scale for uf

  922.  * @param scaleh scale for vf

  923.  */

  924. static void cube_to_xyz(const V360Context *s,

  925.                         float uf, float vf, int face,

  926.                         float *vec, float scalew, float scaleh)

  927. {

  928.     const int direction = s->out_cubemap_direction_order[face];

  929.     float l_x, l_y, l_z;

  930. 

  931.     uf /= scalew;

  932.     vf /= scaleh;

  933. 

  934.     rotate_cube_face_inverse(&uf, &vf, s->out_cubemap_face_rotation[face]);

  935. 

  936.     switch (direction) {

  937.     case RIGHT:

  938.         l_x =  1.f;

  939.         l_y = -vf;

  940.         l_z =  uf;

  941.         break;

  942.     case LEFT:

  943.         l_x = -1.f;

  944.         l_y = -vf;

  945.         l_z = -uf;

  946.         break;

  947.     case UP:

  948.         l_x =  uf;

  949.         l_y =  1.f;

  950.         l_z = -vf;

  951.         break;

  952.     case DOWN:

  953.         l_x =  uf;

  954.         l_y = -1.f;

  955.         l_z =  vf;

  956.         break;

  957.     case FRONT:

  958.         l_x =  uf;

  959.         l_y = -vf;

  960.         l_z = -1.f;

  961.         break;

  962.     case BACK:

  963.         l_x = -uf;

  964.         l_y = -vf;

  965.         l_z =  1.f;

  966.         break;

  967.     default:

  968.         av_assert0(0);

  969.     }

  970. 

  971.     vec[0] = l_x;

  972.     vec[1] = l_y;

  973.     vec[2] = l_z;

  974. 

  975.     normalize_vector(vec);

  976. }

  977. 

  978. /**

  979.  * Calculate cubemap position for corresponding 3D coordinates on sphere.

  980.  * Common operation for every cubemap.

  981.  *

  982.  * @param s filter private context

  983.  * @param vec coordinated on sphere

  984.  * @param uf horizontal cubemap coordinate [0, 1)

  985.  * @param vf vertical cubemap coordinate [0, 1)

  986.  * @param direction direction of view

  987.  */

  988. static void xyz_to_cube(const V360Context *s,

  989.                         const float *vec,

  990.                         float *uf, float *vf, int *direction)

  991. {

  992.     const float phi   = atan2f(vec[0], -vec[2]);

  993.     const float theta = asinf(-vec[1]);

  994.     float phi_norm, theta_threshold;

  995.     int face;

  996. 

  997.     if (phi >= -M_PI_4 && phi < M_PI_4) {

  998.         *direction = FRONT;

  999.         phi_norm = phi;

  1000.     } else if (phi >= -(M_PI_2 + M_PI_4) && phi < -M_PI_4) {

  1001.         *direction = LEFT;

  1002.         phi_norm = phi + M_PI_2;

  1003.     } else if (phi >= M_PI_4 && phi < M_PI_2 + M_PI_4) {

  1004.         *direction = RIGHT;

  1005.         phi_norm = phi - M_PI_2;

  1006.     } else {

  1007.         *direction = BACK;

  1008.         phi_norm = phi + ((phi > 0.f) ? -M_PI : M_PI);

  1009.     }

  1010. 

  1011.     theta_threshold = atanf(cosf(phi_norm));

  1012.     if (theta > theta_threshold) {

  1013.         *direction = DOWN;

  1014.     } else if (theta < -theta_threshold) {

  1015.         *direction = UP;

  1016.     }

  1017. 

  1018.     switch (*direction) {

  1019.     case RIGHT:

  1020.         *uf =  vec[2] / vec[0];

  1021.         *vf = -vec[1] / vec[0];

  1022.         break;

  1023.     case LEFT:

  1024.         *uf =  vec[2] / vec[0];

  1025.         *vf =  vec[1] / vec[0];

  1026.         break;

  1027.     case UP:

  1028.         *uf =  vec[0] / vec[1];

  1029.         *vf = -vec[2] / vec[1];

  1030.         break;

  1031.     case DOWN:

  1032.         *uf = -vec[0] / vec[1];

  1033.         *vf = -vec[2] / vec[1];

  1034.         break;

  1035.     case FRONT:

  1036.         *uf = -vec[0] / vec[2];

  1037.         *vf =  vec[1] / vec[2];

  1038.         break;

  1039.     case BACK:

  1040.         *uf = -vec[0] / vec[2];

  1041.         *vf = -vec[1] / vec[2];

  1042.         break;

  1043.     default:

  1044.         av_assert0(0);

  1045.     }

  1046. 

  1047.     face = s->in_cubemap_face_order[*direction];

  1048.     rotate_cube_face(uf, vf, s->in_cubemap_face_rotation[face]);

  1049. 

  1050.     (*uf) *= s->input_mirror_modifier[0];

  1051.     (*vf) *= s->input_mirror_modifier[1];

  1052. }

  1053. 

  1054. /**

  1055.  * Find position on another cube face in case of overflow/underflow.

  1056.  * Used for calculation of interpolation window.

  1057.  *

  1058.  * @param s filter private context

  1059.  * @param uf horizontal cubemap coordinate

  1060.  * @param vf vertical cubemap coordinate

  1061.  * @param direction direction of view

  1062.  * @param new_uf new horizontal cubemap coordinate

  1063.  * @param new_vf new vertical cubemap coordinate

  1064.  * @param face face position on cubemap

  1065.  */

  1066. static void process_cube_coordinates(const V360Context *s,

  1067.                                      float uf, float vf, int direction,

  1068.                                      float *new_uf, float *new_vf, int *face)

  1069. {

  1070.     /*

  1071.      *  Cubemap orientation

  1072.      *

  1073.      *           width

  1074.      *         <------->

  1075.      *         +-------+

  1076.      *         |       |                              U

  1077.      *         | up    |                   h       ------->

  1078.      * +-------+-------+-------+-------+ ^ e      |

  1079.      * |       |       |       |       | | i    V |

  1080.      * | left  | front | right | back  | | g      |

  1081.      * +-------+-------+-------+-------+ v h      v

  1082.      *         |       |                   t

  1083.      *         | down  |

  1084.      *         +-------+

  1085.      */

  1086. 

  1087.     *face = s->in_cubemap_face_order[direction];

  1088.     rotate_cube_face_inverse(&uf, &vf, s->in_cubemap_face_rotation[*face]);

  1089. 

  1090.     if ((uf < -1.f || uf >= 1.f) && (vf < -1.f || vf >= 1.f)) {

  1091.         // There are no pixels to use in this case

  1092.         *new_uf = uf;

  1093.         *new_vf = vf;

  1094.     } else if (uf < -1.f) {

  1095.         uf += 2.f;

  1096.         switch (direction) {

  1097.         case RIGHT:

  1098.             direction = FRONT;

  1099.             *new_uf =  uf;

  1100.             *new_vf =  vf;

  1101.             break;

  1102.         case LEFT:

  1103.             direction = BACK;

  1104.             *new_uf =  uf;

  1105.             *new_vf =  vf;

  1106.             break;

  1107.         case UP:

  1108.             direction = LEFT;

  1109.             *new_uf =  vf;

  1110.             *new_vf = -uf;

  1111.             break;

  1112.         case DOWN:

  1113.             direction = LEFT;

  1114.             *new_uf = -vf;

  1115.             *new_vf =  uf;

  1116.             break;

  1117.         case FRONT:

  1118.             direction = LEFT;

  1119.             *new_uf =  uf;

  1120.             *new_vf =  vf;

  1121.             break;

  1122.         case BACK:

  1123.             direction = RIGHT;

  1124.             *new_uf =  uf;

  1125.             *new_vf =  vf;

  1126.             break;

  1127.         default:

  1128.             av_assert0(0);

  1129.         }

  1130.     } else if (uf >= 1.f) {

  1131.         uf -= 2.f;

  1132.         switch (direction) {

  1133.         case RIGHT:

  1134.             direction = BACK;

  1135.             *new_uf =  uf;

  1136.             *new_vf =  vf;

  1137.             break;

  1138.         case LEFT:

  1139.             direction = FRONT;

  1140.             *new_uf =  uf;

  1141.             *new_vf =  vf;

  1142.             break;

  1143.         case UP:

  1144.             direction = RIGHT;

  1145.             *new_uf = -vf;

  1146.             *new_vf =  uf;

  1147.             break;

  1148.         case DOWN:

  1149.             direction = RIGHT;

  1150.             *new_uf =  vf;

  1151.             *new_vf = -uf;

  1152.             break;

  1153.         case FRONT:

  1154.             direction = RIGHT;

  1155.             *new_uf =  uf;

  1156.             *new_vf =  vf;

  1157.             break;

  1158.         case BACK:

  1159.             direction = LEFT;

  1160.             *new_uf =  uf;

  1161.             *new_vf =  vf;

  1162.             break;

  1163.         default:

  1164.             av_assert0(0);

  1165.         }

  1166.     } else if (vf < -1.f) {

  1167.         vf += 2.f;

  1168.         switch (direction) {

  1169.         case RIGHT:

  1170.             direction = UP;

  1171.             *new_uf =  vf;

  1172.             *new_vf = -uf;

  1173.             break;

  1174.         case LEFT:

  1175.             direction = UP;

  1176.             *new_uf = -vf;

  1177.             *new_vf =  uf;

  1178.             break;

  1179.         case UP:

  1180.             direction = BACK;

  1181.             *new_uf = -uf;

  1182.             *new_vf = -vf;

  1183.             break;

  1184.         case DOWN:

  1185.             direction = FRONT;

  1186.             *new_uf =  uf;

  1187.             *new_vf =  vf;

  1188.             break;

  1189.         case FRONT:

  1190.             direction = UP;

  1191.             *new_uf =  uf;

  1192.             *new_vf =  vf;

  1193.             break;

  1194.         case BACK:

  1195.             direction = UP;

  1196.             *new_uf = -uf;

  1197.             *new_vf = -vf;

  1198.             break;

  1199.         default:

  1200.             av_assert0(0);

  1201.         }

  1202.     } else if (vf >= 1.f) {

  1203.         vf -= 2.f;

  1204.         switch (direction) {

  1205.         case RIGHT:

  1206.             direction = DOWN;

  1207.             *new_uf = -vf;

  1208.             *new_vf =  uf;

  1209.             break;

  1210.         case LEFT:

  1211.             direction = DOWN;

  1212.             *new_uf =  vf;

  1213.             *new_vf = -uf;

  1214.             break;

  1215.         case UP:

  1216.             direction = FRONT;

  1217.             *new_uf =  uf;

  1218.             *new_vf =  vf;

  1219.             break;

  1220.         case DOWN:

  1221.             direction = BACK;

  1222.             *new_uf = -uf;

  1223.             *new_vf = -vf;

  1224.             break;

  1225.         case FRONT:

  1226.             direction = DOWN;

  1227.             *new_uf =  uf;

  1228.             *new_vf =  vf;

  1229.             break;

  1230.         case BACK:

  1231.             direction = DOWN;

  1232.             *new_uf = -uf;

  1233.             *new_vf = -vf;

  1234.             break;

  1235.         default:

  1236.             av_assert0(0);

  1237.         }

  1238.     } else {

  1239.         // Inside cube face

  1240.         *new_uf = uf;

  1241.         *new_vf = vf;

  1242.     }

  1243. 

  1244.     *face = s->in_cubemap_face_order[direction];

  1245.     rotate_cube_face(new_uf, new_vf, s->in_cubemap_face_rotation[*face]);

  1246. }

  1247. 

  1248. /**

  1249.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap3x2 format.

  1250.  *

  1251.  * @param s filter private context

  1252.  * @param i horizontal position on frame [0, width)

  1253.  * @param j vertical position on frame [0, height)

  1254.  * @param width frame width

  1255.  * @param height frame height

  1256.  * @param vec coordinates on sphere

  1257.  */

  1258. static int cube3x2_to_xyz(const V360Context *s,

  1259.                           int i, int j, int width, int height,

  1260.                           float *vec)

  1261. {

  1262.     const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_width  / 3.f) : 1.f - s->out_pad;

  1263.     const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_height / 2.f) : 1.f - s->out_pad;

  1264. 

  1265.     const float ew = width  / 3.f;

  1266.     const float eh = height / 2.f;

  1267. 

  1268.     const int u_face = floorf(i / ew);

  1269.     const int v_face = floorf(j / eh);

  1270.     const int face = u_face + 3 * v_face;

  1271. 

  1272.     const int u_shift = ceilf(ew * u_face);

  1273.     const int v_shift = ceilf(eh * v_face);

  1274.     const int ewi = ceilf(ew * (u_face + 1)) - u_shift;

  1275.     const int ehi = ceilf(eh * (v_face + 1)) - v_shift;

  1276. 

  1277.     const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;

  1278.     const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;

  1279. 

  1280.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1281. 

  1282.     return 1;

  1283. }

  1284. 

  1285. /**

  1286.  * Calculate frame position in cubemap3x2 format for corresponding 3D coordinates on sphere.

  1287.  *

  1288.  * @param s filter private context

  1289.  * @param vec coordinates on sphere

  1290.  * @param width frame width

  1291.  * @param height frame height

  1292.  * @param us horizontal coordinates for interpolation window

  1293.  * @param vs vertical coordinates for interpolation window

  1294.  * @param du horizontal relative coordinate

  1295.  * @param dv vertical relative coordinate

  1296.  */

  1297. static int xyz_to_cube3x2(const V360Context *s,

  1298.                           const float *vec, int width, int height,

  1299.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1300. {

  1301.     const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_width  / 3.f) : 1.f - s->in_pad;

  1302.     const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_height / 2.f) : 1.f - s->in_pad;

  1303.     const float ew = width  / 3.f;

  1304.     const float eh = height / 2.f;

  1305.     float uf, vf;

  1306.     int ui, vi;

  1307.     int ewi, ehi;

  1308.     int direction, face;

  1309.     int u_face, v_face;

  1310. 

  1311.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1312. 

  1313.     uf *= scalew;

  1314.     vf *= scaleh;

  1315. 

  1316.     face = s->in_cubemap_face_order[direction];

  1317.     u_face = face % 3;

  1318.     v_face = face / 3;

  1319.     ewi = ceilf(ew * (u_face + 1)) - ceilf(ew * u_face);

  1320.     ehi = ceilf(eh * (v_face + 1)) - ceilf(eh * v_face);

  1321. 

  1322.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1323.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1324. 

  1325.     ui = floorf(uf);

  1326.     vi = floorf(vf);

  1327. 

  1328.     *du = uf - ui;

  1329.     *dv = vf - vi;

  1330. 

  1331.     for (int i = 0; i < 4; i++) {

  1332.         for (int j = 0; j < 4; j++) {

  1333.             int new_ui = ui + j - 1;

  1334.             int new_vi = vi + i - 1;

  1335.             int u_shift, v_shift;

  1336.             int new_ewi, new_ehi;

  1337. 

  1338.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1339.                 face = s->in_cubemap_face_order[direction];

  1340. 

  1341.                 u_face = face % 3;

  1342.                 v_face = face / 3;

  1343.                 u_shift = ceilf(ew * u_face);

  1344.                 v_shift = ceilf(eh * v_face);

  1345.             } else {

  1346.                 uf = 2.f * new_ui / ewi - 1.f;

  1347.                 vf = 2.f * new_vi / ehi - 1.f;

  1348. 

  1349.                 uf /= scalew;

  1350.                 vf /= scaleh;

  1351. 

  1352.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1353. 

  1354.                 uf *= scalew;

  1355.                 vf *= scaleh;

  1356. 

  1357.                 u_face = face % 3;

  1358.                 v_face = face / 3;

  1359.                 u_shift = ceilf(ew * u_face);

  1360.                 v_shift = ceilf(eh * v_face);

  1361.                 new_ewi = ceilf(ew * (u_face + 1)) - u_shift;

  1362.                 new_ehi = ceilf(eh * (v_face + 1)) - v_shift;

  1363. 

  1364.                 new_ui = av_clip(lrintf(0.5f * new_ewi * (uf + 1.f)), 0, new_ewi - 1);

  1365.                 new_vi = av_clip(lrintf(0.5f * new_ehi * (vf + 1.f)), 0, new_ehi - 1);

  1366.             }

  1367. 

  1368.             us[i][j] = u_shift + new_ui;

  1369.             vs[i][j] = v_shift + new_vi;

  1370.         }

  1371.     }

  1372. 

  1373.     return 1;

  1374. }

  1375. 

  1376. /**

  1377.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap1x6 format.

  1378.  *

  1379.  * @param s filter private context

  1380.  * @param i horizontal position on frame [0, width)

  1381.  * @param j vertical position on frame [0, height)

  1382.  * @param width frame width

  1383.  * @param height frame height

  1384.  * @param vec coordinates on sphere

  1385.  */

  1386. static int cube1x6_to_xyz(const V360Context *s,

  1387.                           int i, int j, int width, int height,

  1388.                           float *vec)

  1389. {

  1390.     const float scalew = s->fout_pad > 0 ? 1.f - (float)(s->fout_pad) / s->out_width : 1.f - s->out_pad;

  1391.     const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_height / 6.f) : 1.f - s->out_pad;

  1392. 

  1393.     const float ew = width;

  1394.     const float eh = height / 6.f;

  1395. 

  1396.     const int face = floorf(j / eh);

  1397. 

  1398.     const int v_shift = ceilf(eh * face);

  1399.     const int ehi = ceilf(eh * (face + 1)) - v_shift;

  1400. 

  1401.     const float uf = 2.f * (i           + 0.5f) / ew  - 1.f;

  1402.     const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;

  1403. 

  1404.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1405. 

  1406.     return 1;

  1407. }

  1408. 

  1409. /**

  1410.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap6x1 format.

  1411.  *

  1412.  * @param s filter private context

  1413.  * @param i horizontal position on frame [0, width)

  1414.  * @param j vertical position on frame [0, height)

  1415.  * @param width frame width

  1416.  * @param height frame height

  1417.  * @param vec coordinates on sphere

  1418.  */

  1419. static int cube6x1_to_xyz(const V360Context *s,

  1420.                           int i, int j, int width, int height,

  1421.                           float *vec)

  1422. {

  1423.     const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_width / 6.f)   : 1.f - s->out_pad;

  1424.     const float scaleh = s->fout_pad > 0 ? 1.f - (float)(s->fout_pad) / s->out_height : 1.f - s->out_pad;

  1425. 

  1426.     const float ew = width / 6.f;

  1427.     const float eh = height;

  1428. 

  1429.     const int face = floorf(i / ew);

  1430. 

  1431.     const int u_shift = ceilf(ew * face);

  1432.     const int ewi = ceilf(ew * (face + 1)) - u_shift;

  1433. 

  1434.     const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;

  1435.     const float vf = 2.f * (j           + 0.5f) / eh  - 1.f;

  1436. 

  1437.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1438. 

  1439.     return 1;

  1440. }

  1441. 

  1442. /**

  1443.  * Calculate frame position in cubemap1x6 format for corresponding 3D coordinates on sphere.

  1444.  *

  1445.  * @param s filter private context

  1446.  * @param vec coordinates on sphere

  1447.  * @param width frame width

  1448.  * @param height frame height

  1449.  * @param us horizontal coordinates for interpolation window

  1450.  * @param vs vertical coordinates for interpolation window

  1451.  * @param du horizontal relative coordinate

  1452.  * @param dv vertical relative coordinate

  1453.  */

  1454. static int xyz_to_cube1x6(const V360Context *s,

  1455.                           const float *vec, int width, int height,

  1456.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1457. {

  1458.     const float scalew = s->fin_pad > 0 ? 1.f - (float)(s->fin_pad) / s->in_width : 1.f - s->in_pad;

  1459.     const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_height / 6.f) : 1.f - s->in_pad;

  1460.     const float eh = height / 6.f;

  1461.     const int ewi = width;

  1462.     float uf, vf;

  1463.     int ui, vi;

  1464.     int ehi;

  1465.     int direction, face;

  1466. 

  1467.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1468. 

  1469.     uf *= scalew;

  1470.     vf *= scaleh;

  1471. 

  1472.     face = s->in_cubemap_face_order[direction];

  1473.     ehi = ceilf(eh * (face + 1)) - ceilf(eh * face);

  1474. 

  1475.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1476.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1477. 

  1478.     ui = floorf(uf);

  1479.     vi = floorf(vf);

  1480. 

  1481.     *du = uf - ui;

  1482.     *dv = vf - vi;

  1483. 

  1484.     for (int i = 0; i < 4; i++) {

  1485.         for (int j = 0; j < 4; j++) {

  1486.             int new_ui = ui + j - 1;

  1487.             int new_vi = vi + i - 1;

  1488.             int v_shift;

  1489.             int new_ehi;

  1490. 

  1491.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1492.                 face = s->in_cubemap_face_order[direction];

  1493. 

  1494.                 v_shift = ceilf(eh * face);

  1495.             } else {

  1496.                 uf = 2.f * new_ui / ewi - 1.f;

  1497.                 vf = 2.f * new_vi / ehi - 1.f;

  1498. 

  1499.                 uf /= scalew;

  1500.                 vf /= scaleh;

  1501. 

  1502.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1503. 

  1504.                 uf *= scalew;

  1505.                 vf *= scaleh;

  1506. 

  1507.                 v_shift = ceilf(eh * face);

  1508.                 new_ehi = ceilf(eh * (face + 1)) - v_shift;

  1509. 

  1510.                 new_ui = av_clip(lrintf(0.5f *     ewi * (uf + 1.f)), 0,     ewi - 1);

  1511.                 new_vi = av_clip(lrintf(0.5f * new_ehi * (vf + 1.f)), 0, new_ehi - 1);

  1512.             }

  1513. 

  1514.             us[i][j] =           new_ui;

  1515.             vs[i][j] = v_shift + new_vi;

  1516.         }

  1517.     }

  1518. 

  1519.     return 1;

  1520. }

  1521. 

  1522. /**

  1523.  * Calculate frame position in cubemap6x1 format for corresponding 3D coordinates on sphere.

  1524.  *

  1525.  * @param s filter private context

  1526.  * @param vec coordinates on sphere

  1527.  * @param width frame width

  1528.  * @param height frame height

  1529.  * @param us horizontal coordinates for interpolation window

  1530.  * @param vs vertical coordinates for interpolation window

  1531.  * @param du horizontal relative coordinate

  1532.  * @param dv vertical relative coordinate

  1533.  */

  1534. static int xyz_to_cube6x1(const V360Context *s,

  1535.                           const float *vec, int width, int height,

  1536.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1537. {

  1538.     const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_width / 6.f)   : 1.f - s->in_pad;

  1539.     const float scaleh = s->fin_pad > 0 ? 1.f - (float)(s->fin_pad) / s->in_height : 1.f - s->in_pad;

  1540.     const float ew = width / 6.f;

  1541.     const int ehi = height;

  1542.     float uf, vf;

  1543.     int ui, vi;

  1544.     int ewi;

  1545.     int direction, face;

  1546. 

  1547.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1548. 

  1549.     uf *= scalew;

  1550.     vf *= scaleh;

  1551. 

  1552.     face = s->in_cubemap_face_order[direction];

  1553.     ewi = ceilf(ew * (face + 1)) - ceilf(ew * face);

  1554. 

  1555.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1556.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1557. 

  1558.     ui = floorf(uf);

  1559.     vi = floorf(vf);

  1560. 

  1561.     *du = uf - ui;

  1562.     *dv = vf - vi;

  1563. 

  1564.     for (int i = 0; i < 4; i++) {

  1565.         for (int j = 0; j < 4; j++) {

  1566.             int new_ui = ui + j - 1;

  1567.             int new_vi = vi + i - 1;

  1568.             int u_shift;

  1569.             int new_ewi;

  1570. 

  1571.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1572.                 face = s->in_cubemap_face_order[direction];

  1573. 

  1574.                 u_shift = ceilf(ew * face);

  1575.             } else {

  1576.                 uf = 2.f * new_ui / ewi - 1.f;

  1577.                 vf = 2.f * new_vi / ehi - 1.f;

  1578. 

  1579.                 uf /= scalew;

  1580.                 vf /= scaleh;

  1581. 

  1582.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1583. 

  1584.                 uf *= scalew;

  1585.                 vf *= scaleh;

  1586. 

  1587.                 u_shift = ceilf(ew * face);

  1588.                 new_ewi = ceilf(ew * (face + 1)) - u_shift;

  1589. 

  1590.                 new_ui = av_clip(lrintf(0.5f * new_ewi * (uf + 1.f)), 0, new_ewi - 1);

  1591.                 new_vi = av_clip(lrintf(0.5f *     ehi * (vf + 1.f)), 0,     ehi - 1);

  1592.             }

  1593. 

  1594.             us[i][j] = u_shift + new_ui;

  1595.             vs[i][j] =           new_vi;

  1596.         }

  1597.     }

  1598. 

  1599.     return 1;

  1600. }

  1601. 

  1602. /**

  1603.  * Calculate 3D coordinates on sphere for corresponding frame position in equirectangular format.

  1604.  *

  1605.  * @param s filter private context

  1606.  * @param i horizontal position on frame [0, width)

  1607.  * @param j vertical position on frame [0, height)

  1608.  * @param width frame width

  1609.  * @param height frame height

  1610.  * @param vec coordinates on sphere

  1611.  */

  1612. static int equirect_to_xyz(const V360Context *s,

  1613.                            int i, int j, int width, int height,

  1614.                            float *vec)

  1615. {

  1616.     const float phi   = ((2.f * i + 0.5f) / width  - 1.f) * M_PI;

  1617.     const float theta = ((2.f * j + 0.5f) / height - 1.f) * M_PI_2;

  1618. 

  1619.     const float sin_phi   = sinf(phi);

  1620.     const float cos_phi   = cosf(phi);

  1621.     const float sin_theta = sinf(theta);

  1622.     const float cos_theta = cosf(theta);

  1623. 

  1624.     vec[0] =  cos_theta * sin_phi;

  1625.     vec[1] = -sin_theta;

  1626.     vec[2] = -cos_theta * cos_phi;

  1627. 

  1628.     return 1;

  1629. }

  1630. 

  1631. /**

  1632.  * Prepare data for processing stereographic output format.

  1633.  *

  1634.  * @param ctx filter context

  1635.  *

  1636.  * @return error code

  1637.  */

  1638. static int prepare_stereographic_out(AVFilterContext *ctx)

  1639. {

  1640.     V360Context *s = ctx->priv;

  1641. 

  1642.     s->flat_range[0] = tanf(FFMIN(s->h_fov, 359.f) * M_PI / 720.f);

  1643.     s->flat_range[1] = tanf(FFMIN(s->v_fov, 359.f) * M_PI / 720.f);

  1644. 

  1645.     return 0;

  1646. }

  1647. 

  1648. /**

  1649.  * Calculate 3D coordinates on sphere for corresponding frame position in stereographic format.

  1650.  *

  1651.  * @param s filter private context

  1652.  * @param i horizontal position on frame [0, width)

  1653.  * @param j vertical position on frame [0, height)

  1654.  * @param width frame width

  1655.  * @param height frame height

  1656.  * @param vec coordinates on sphere

  1657.  */

  1658. static int stereographic_to_xyz(const V360Context *s,

  1659.                                 int i, int j, int width, int height,

  1660.                                 float *vec)

  1661. {

  1662.     const float x = ((2.f * i + 1.f) / width  - 1.f) * s->flat_range[0];

  1663.     const float y = ((2.f * j + 1.f) / height - 1.f) * s->flat_range[1];

  1664.     const float xy = x * x + y * y;

  1665. 

  1666.     vec[0] = 2.f * x / (1.f + xy);

  1667.     vec[1] = (-1.f + xy) / (1.f + xy);

  1668.     vec[2] = 2.f * y / (1.f + xy);

  1669. 

  1670.     normalize_vector(vec);

  1671. 

  1672.     return 1;

  1673. }

  1674. 

  1675. /**

  1676.  * Prepare data for processing stereographic input format.

  1677.  *

  1678.  * @param ctx filter context

  1679.  *

  1680.  * @return error code

  1681.  */

  1682. static int prepare_stereographic_in(AVFilterContext *ctx)

  1683. {

  1684.     V360Context *s = ctx->priv;

  1685. 

  1686.     s->iflat_range[0] = tanf(FFMIN(s->ih_fov, 359.f) * M_PI / 720.f);

  1687.     s->iflat_range[1] = tanf(FFMIN(s->iv_fov, 359.f) * M_PI / 720.f);

  1688. 

  1689.     return 0;

  1690. }

  1691. 

  1692. /**

  1693.  * Calculate frame position in stereographic format for corresponding 3D coordinates on sphere.

  1694.  *

  1695.  * @param s filter private context

  1696.  * @param vec coordinates on sphere

  1697.  * @param width frame width

  1698.  * @param height frame height

  1699.  * @param us horizontal coordinates for interpolation window

  1700.  * @param vs vertical coordinates for interpolation window

  1701.  * @param du horizontal relative coordinate

  1702.  * @param dv vertical relative coordinate

  1703.  */

  1704. static int xyz_to_stereographic(const V360Context *s,

  1705.                                 const float *vec, int width, int height,

  1706.                                 int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1707. {

  1708.     const float x = vec[0] / (1.f - vec[1]) / s->iflat_range[0] * s->input_mirror_modifier[0];

  1709.     const float y = vec[2] / (1.f - vec[1]) / s->iflat_range[1] * s->input_mirror_modifier[1];

  1710.     float uf, vf;

  1711.     int visible, ui, vi;

  1712. 

  1713.     uf = (x + 1.f) * width  / 2.f;

  1714.     vf = (y + 1.f) * height / 2.f;

  1715.     ui = floorf(uf);

  1716.     vi = floorf(vf);

  1717. 

  1718.     visible = isfinite(x) && isfinite(y) && vi >= 0 && vi < height && ui >= 0 && ui < width;

  1719. 

  1720.     *du = visible ? uf - ui : 0.f;

  1721.     *dv = visible ? vf - vi : 0.f;

  1722. 

  1723.     for (int i = 0; i < 4; i++) {

  1724.         for (int j = 0; j < 4; j++) {

  1725.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  1726.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  1727.         }

  1728.     }

  1729. 

  1730.     return visible;

  1731. }

  1732. 

  1733. /**

  1734.  * Calculate frame position in equirectangular format for corresponding 3D coordinates on sphere.

  1735.  *

  1736.  * @param s filter private context

  1737.  * @param vec coordinates on sphere

  1738.  * @param width frame width

  1739.  * @param height frame height

  1740.  * @param us horizontal coordinates for interpolation window

  1741.  * @param vs vertical coordinates for interpolation window

  1742.  * @param du horizontal relative coordinate

  1743.  * @param dv vertical relative coordinate

  1744.  */

  1745. static int xyz_to_equirect(const V360Context *s,

  1746.                            const float *vec, int width, int height,

  1747.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1748. {

  1749.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  1750.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  1751.     float uf, vf;

  1752.     int ui, vi;

  1753. 

  1754.     uf = (phi   / M_PI   + 1.f) * width  / 2.f;

  1755.     vf = (theta / M_PI_2 + 1.f) * height / 2.f;

  1756.     ui = floorf(uf);

  1757.     vi = floorf(vf);

  1758. 

  1759.     *du = uf - ui;

  1760.     *dv = vf - vi;

  1761. 

  1762.     for (int i = 0; i < 4; i++) {

  1763.         for (int j = 0; j < 4; j++) {

  1764.             us[i][j] = ereflectx(ui + j - 1, vi + i - 1, width, height);

  1765.             vs[i][j] = reflecty(vi + i - 1, height);

  1766.         }

  1767.     }

  1768. 

  1769.     return 1;

  1770. }

  1771. 

  1772. /**

  1773.  * Prepare data for processing flat input format.

  1774.  *

  1775.  * @param ctx filter context

  1776.  *

  1777.  * @return error code

  1778.  */

  1779. static int prepare_flat_in(AVFilterContext *ctx)

  1780. {

  1781.     V360Context *s = ctx->priv;

  1782. 

  1783.     s->iflat_range[0] = tanf(0.5f * s->ih_fov * M_PI / 180.f);

  1784.     s->iflat_range[1] = tanf(0.5f * s->iv_fov * M_PI / 180.f);

  1785. 

  1786.     return 0;

  1787. }

  1788. 

  1789. /**

  1790.  * Calculate frame position in flat format for corresponding 3D coordinates on sphere.

  1791.  *

  1792.  * @param s filter private context

  1793.  * @param vec coordinates on sphere

  1794.  * @param width frame width

  1795.  * @param height frame height

  1796.  * @param us horizontal coordinates for interpolation window

  1797.  * @param vs vertical coordinates for interpolation window

  1798.  * @param du horizontal relative coordinate

  1799.  * @param dv vertical relative coordinate

  1800.  */

  1801. static int xyz_to_flat(const V360Context *s,

  1802.                        const float *vec, int width, int height,

  1803.                        int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1804. {

  1805.     const float theta = acosf(vec[2]);

  1806.     const float r = tanf(theta);

  1807.     const float rr = fabsf(r) < 1e+6f ? r : hypotf(width, height);

  1808.     const float zf = -vec[2];

  1809.     const float h = hypotf(vec[0], vec[1]);

  1810.     const float c = h <= 1e-6f ? 1.f : rr / h;

  1811.     float uf = -vec[0] * c / s->iflat_range[0] * s->input_mirror_modifier[0];

  1812.     float vf =  vec[1] * c / s->iflat_range[1] * s->input_mirror_modifier[1];

  1813.     int visible, ui, vi;

  1814. 

  1815.     uf = zf >= 0.f ? (uf + 1.f) * width  / 2.f : 0.f;

  1816.     vf = zf >= 0.f ? (vf + 1.f) * height / 2.f : 0.f;

  1817. 

  1818.     ui = floorf(uf);

  1819.     vi = floorf(vf);

  1820. 

  1821.     visible = vi >= 0 && vi < height && ui >= 0 && ui < width && zf >= 0.f;

  1822. 

  1823.     *du = uf - ui;

  1824.     *dv = vf - vi;

  1825. 

  1826.     for (int i = 0; i < 4; i++) {

  1827.         for (int j = 0; j < 4; j++) {

  1828.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  1829.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  1830.         }

  1831.     }

  1832. 

  1833.     return visible;

  1834. }

  1835. 

  1836. /**

  1837.  * Calculate frame position in mercator format for corresponding 3D coordinates on sphere.

  1838.  *

  1839.  * @param s filter private context

  1840.  * @param vec coordinates on sphere

  1841.  * @param width frame width

  1842.  * @param height frame height

  1843.  * @param us horizontal coordinates for interpolation window

  1844.  * @param vs vertical coordinates for interpolation window

  1845.  * @param du horizontal relative coordinate

  1846.  * @param dv vertical relative coordinate

  1847.  */

  1848. static int xyz_to_mercator(const V360Context *s,

  1849.                            const float *vec, int width, int height,

  1850.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1851. {

  1852.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  1853.     const float theta = -vec[1] * s->input_mirror_modifier[1];

  1854.     float uf, vf;

  1855.     int ui, vi;

  1856. 

  1857.     uf = (phi / M_PI + 1.f) * width / 2.f;

  1858.     vf = (av_clipf(logf((1.f + theta) / (1.f - theta)) / (2.f * M_PI), -1.f, 1.f) + 1.f) * height / 2.f;

  1859.     ui = floorf(uf);

  1860.     vi = floorf(vf);

  1861. 

  1862.     *du = uf - ui;

  1863.     *dv = vf - vi;

  1864. 

  1865.     for (int i = 0; i < 4; i++) {

  1866.         for (int j = 0; j < 4; j++) {

  1867.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  1868.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  1869.         }

  1870.     }

  1871. 

  1872.     return 1;

  1873. }

  1874. 

  1875. /**

  1876.  * Calculate 3D coordinates on sphere for corresponding frame position in mercator format.

  1877.  *

  1878.  * @param s filter private context

  1879.  * @param i horizontal position on frame [0, width)

  1880.  * @param j vertical position on frame [0, height)

  1881.  * @param width frame width

  1882.  * @param height frame height

  1883.  * @param vec coordinates on sphere

  1884.  */

  1885. static int mercator_to_xyz(const V360Context *s,

  1886.                            int i, int j, int width, int height,

  1887.                            float *vec)

  1888. {

  1889.     const float phi = ((2.f * i + 1.f) / width  - 1.f) * M_PI + M_PI_2;

  1890.     const float y   = ((2.f * j + 1.f) / height - 1.f) * M_PI;

  1891.     const float div = expf(2.f * y) + 1.f;

  1892. 

  1893.     const float sin_phi   = sinf(phi);

  1894.     const float cos_phi   = cosf(phi);

  1895.     const float sin_theta = -2.f * expf(y) / div;

  1896.     const float cos_theta = -(expf(2.f * y) - 1.f) / div;

  1897. 

  1898.     vec[0] = sin_theta * cos_phi;

  1899.     vec[1] = cos_theta;

  1900.     vec[2] = sin_theta * sin_phi;

  1901. 

  1902.     return 1;

  1903. }

  1904. 

  1905. /**

  1906.  * Calculate frame position in ball format for corresponding 3D coordinates on sphere.

  1907.  *

  1908.  * @param s filter private context

  1909.  * @param vec coordinates on sphere

  1910.  * @param width frame width

  1911.  * @param height frame height

  1912.  * @param us horizontal coordinates for interpolation window

  1913.  * @param vs vertical coordinates for interpolation window

  1914.  * @param du horizontal relative coordinate

  1915.  * @param dv vertical relative coordinate

  1916.  */

  1917. static int xyz_to_ball(const V360Context *s,

  1918.                        const float *vec, int width, int height,

  1919.                        int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1920. {

  1921.     const float l = hypotf(vec[0], vec[1]);

  1922.     const float r = sqrtf(1.f + vec[2]) / M_SQRT2;

  1923.     float uf, vf;

  1924.     int ui, vi;

  1925. 

  1926.     uf = (1.f + r * vec[0] * s->input_mirror_modifier[0] / (l > 0.f ? l : 1.f)) * width  * 0.5f;

  1927.     vf = (1.f - r * vec[1] * s->input_mirror_modifier[1] / (l > 0.f ? l : 1.f)) * height * 0.5f;

  1928. 

  1929.     ui = floorf(uf);

  1930.     vi = floorf(vf);

  1931. 

  1932.     *du = uf - ui;

  1933.     *dv = vf - vi;

  1934. 

  1935.     for (int i = 0; i < 4; i++) {

  1936.         for (int j = 0; j < 4; j++) {

  1937.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  1938.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  1939.         }

  1940.     }

  1941. 

  1942.     return 1;

  1943. }

  1944. 

  1945. /**

  1946.  * Calculate 3D coordinates on sphere for corresponding frame position in ball format.

  1947.  *

  1948.  * @param s filter private context

  1949.  * @param i horizontal position on frame [0, width)

  1950.  * @param j vertical position on frame [0, height)

  1951.  * @param width frame width

  1952.  * @param height frame height

  1953.  * @param vec coordinates on sphere

  1954.  */

  1955. static int ball_to_xyz(const V360Context *s,

  1956.                        int i, int j, int width, int height,

  1957.                        float *vec)

  1958. {

  1959.     const float x = (2.f * i + 1.f) / width  - 1.f;

  1960.     const float y = (2.f * j + 1.f) / height - 1.f;

  1961.     const float l = hypotf(x, y);

  1962. 

  1963.     if (l <= 1.f) {

  1964.         const float z = 2.f * l * sqrtf(1.f - l * l);

  1965. 

  1966.         vec[0] =  z * x / (l > 0.f ? l : 1.f);

  1967.         vec[1] = -z * y / (l > 0.f ? l : 1.f);

  1968.         vec[2] = -1.f + 2.f * l * l;

  1969.     } else {

  1970.         vec[0] =  0.f;

  1971.         vec[1] = -1.f;

  1972.         vec[2] =  0.f;

  1973.         return 0;

  1974.     }

  1975. 

  1976.     return 1;

  1977. }

  1978. 

  1979. /**

  1980.  * Calculate 3D coordinates on sphere for corresponding frame position in hammer format.

  1981.  *

  1982.  * @param s filter private context

  1983.  * @param i horizontal position on frame [0, width)

  1984.  * @param j vertical position on frame [0, height)

  1985.  * @param width frame width

  1986.  * @param height frame height

  1987.  * @param vec coordinates on sphere

  1988.  */

  1989. static int hammer_to_xyz(const V360Context *s,

  1990.                          int i, int j, int width, int height,

  1991.                          float *vec)

  1992. {

  1993.     const float x = ((2.f * i + 1.f) / width  - 1.f);

  1994.     const float y = ((2.f * j + 1.f) / height - 1.f);

  1995. 

  1996.     const float xx = x * x;

  1997.     const float yy = y * y;

  1998. 

  1999.     const float z = sqrtf(1.f - xx * 0.5f - yy * 0.5f);

  2000. 

  2001.     const float a = M_SQRT2 * x * z;

  2002.     const float b = 2.f * z * z - 1.f;

  2003. 

  2004.     const float aa = a * a;

  2005.     const float bb = b * b;

  2006. 

  2007.     const float w = sqrtf(1.f - 2.f * yy * z * z);

  2008. 

  2009.     vec[0] =  w * 2.f * a * b / (aa + bb);

  2010.     vec[1] = -M_SQRT2 * y * z;

  2011.     vec[2] = -w * (bb  - aa) / (aa + bb);

  2012. 

  2013.     normalize_vector(vec);

  2014. 

  2015.     return 1;

  2016. }

  2017. 

  2018. /**

  2019.  * Calculate frame position in hammer format for corresponding 3D coordinates on sphere.

  2020.  *

  2021.  * @param s filter private context

  2022.  * @param vec coordinates on sphere

  2023.  * @param width frame width

  2024.  * @param height frame height

  2025.  * @param us horizontal coordinates for interpolation window

  2026.  * @param vs vertical coordinates for interpolation window

  2027.  * @param du horizontal relative coordinate

  2028.  * @param dv vertical relative coordinate

  2029.  */

  2030. static int xyz_to_hammer(const V360Context *s,

  2031.                          const float *vec, int width, int height,

  2032.                          int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2033. {

  2034.     const float theta = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  2035. 

  2036.     const float z = sqrtf(1.f + sqrtf(1.f - vec[1] * vec[1]) * cosf(theta * 0.5f));

  2037.     const float x = sqrtf(1.f - vec[1] * vec[1]) * sinf(theta * 0.5f) / z;

  2038.     const float y = -vec[1] / z * s->input_mirror_modifier[1];

  2039.     float uf, vf;

  2040.     int ui, vi;

  2041. 

  2042.     uf = (x + 1.f) * width  / 2.f;

  2043.     vf = (y + 1.f) * height / 2.f;

  2044.     ui = floorf(uf);

  2045.     vi = floorf(vf);

  2046. 

  2047.     *du = uf - ui;

  2048.     *dv = vf - vi;

  2049. 

  2050.     for (int i = 0; i < 4; i++) {

  2051.         for (int j = 0; j < 4; j++) {

  2052.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2053.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2054.         }

  2055.     }

  2056. 

  2057.     return 1;

  2058. }

  2059. 

  2060. /**

  2061.  * Calculate 3D coordinates on sphere for corresponding frame position in sinusoidal format.

  2062.  *

  2063.  * @param s filter private context

  2064.  * @param i horizontal position on frame [0, width)

  2065.  * @param j vertical position on frame [0, height)

  2066.  * @param width frame width

  2067.  * @param height frame height

  2068.  * @param vec coordinates on sphere

  2069.  */

  2070. static int sinusoidal_to_xyz(const V360Context *s,

  2071.                              int i, int j, int width, int height,

  2072.                              float *vec)

  2073. {

  2074.     const float theta = ((2.f * j + 1.f) / height - 1.f) * M_PI_2;

  2075.     const float phi   = ((2.f * i + 1.f) / width  - 1.f) * M_PI / cosf(theta);

  2076. 

  2077.     const float sin_phi   = sinf(phi);

  2078.     const float cos_phi   = cosf(phi);

  2079.     const float sin_theta = sinf(theta);

  2080.     const float cos_theta = cosf(theta);

  2081. 

  2082.     vec[0] =  cos_theta * sin_phi;

  2083.     vec[1] = -sin_theta;

  2084.     vec[2] = -cos_theta * cos_phi;

  2085. 

  2086.     normalize_vector(vec);

  2087. 

  2088.     return 1;

  2089. }

  2090. 

  2091. /**

  2092.  * Calculate frame position in sinusoidal format for corresponding 3D coordinates on sphere.

  2093.  *

  2094.  * @param s filter private context

  2095.  * @param vec coordinates on sphere

  2096.  * @param width frame width

  2097.  * @param height frame height

  2098.  * @param us horizontal coordinates for interpolation window

  2099.  * @param vs vertical coordinates for interpolation window

  2100.  * @param du horizontal relative coordinate

  2101.  * @param dv vertical relative coordinate

  2102.  */

  2103. static int xyz_to_sinusoidal(const V360Context *s,

  2104.                              const float *vec, int width, int height,

  2105.                              int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2106. {

  2107.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  2108.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0] * cosf(theta);

  2109.     float uf, vf;

  2110.     int ui, vi;

  2111. 

  2112.     uf = (phi   / M_PI   + 1.f) * width  / 2.f;

  2113.     vf = (theta / M_PI_2 + 1.f) * height / 2.f;

  2114.     ui = floorf(uf);

  2115.     vi = floorf(vf);

  2116. 

  2117.     *du = uf - ui;

  2118.     *dv = vf - vi;

  2119. 

  2120.     for (int i = 0; i < 4; i++) {

  2121.         for (int j = 0; j < 4; j++) {

  2122.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2123.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2124.         }

  2125.     }

  2126. 

  2127.     return 1;

  2128. }

  2129. 

  2130. /**

  2131.  * Prepare data for processing equi-angular cubemap input format.

  2132.  *

  2133.  * @param ctx filter context

  2134.  *

  2135.  * @return error code

  2136.  */

  2137. static int prepare_eac_in(AVFilterContext *ctx)

  2138. {

  2139.     V360Context *s = ctx->priv;

  2140. 

  2141.     if (s->ih_flip && s->iv_flip) {

  2142.         s->in_cubemap_face_order[RIGHT] = BOTTOM_LEFT;

  2143.         s->in_cubemap_face_order[LEFT]  = BOTTOM_RIGHT;

  2144.         s->in_cubemap_face_order[UP]    = TOP_LEFT;

  2145.         s->in_cubemap_face_order[DOWN]  = TOP_RIGHT;

  2146.         s->in_cubemap_face_order[FRONT] = BOTTOM_MIDDLE;

  2147.         s->in_cubemap_face_order[BACK]  = TOP_MIDDLE;

  2148.     } else if (s->ih_flip) {

  2149.         s->in_cubemap_face_order[RIGHT] = TOP_LEFT;

  2150.         s->in_cubemap_face_order[LEFT]  = TOP_RIGHT;

  2151.         s->in_cubemap_face_order[UP]    = BOTTOM_LEFT;

  2152.         s->in_cubemap_face_order[DOWN]  = BOTTOM_RIGHT;

  2153.         s->in_cubemap_face_order[FRONT] = TOP_MIDDLE;

  2154.         s->in_cubemap_face_order[BACK]  = BOTTOM_MIDDLE;

  2155.     } else if (s->iv_flip) {

  2156.         s->in_cubemap_face_order[RIGHT] = BOTTOM_RIGHT;

  2157.         s->in_cubemap_face_order[LEFT]  = BOTTOM_LEFT;

  2158.         s->in_cubemap_face_order[UP]    = TOP_RIGHT;

  2159.         s->in_cubemap_face_order[DOWN]  = TOP_LEFT;

  2160.         s->in_cubemap_face_order[FRONT] = BOTTOM_MIDDLE;

  2161.         s->in_cubemap_face_order[BACK]  = TOP_MIDDLE;

  2162.     } else {

  2163.         s->in_cubemap_face_order[RIGHT] = TOP_RIGHT;

  2164.         s->in_cubemap_face_order[LEFT]  = TOP_LEFT;

  2165.         s->in_cubemap_face_order[UP]    = BOTTOM_RIGHT;

  2166.         s->in_cubemap_face_order[DOWN]  = BOTTOM_LEFT;

  2167.         s->in_cubemap_face_order[FRONT] = TOP_MIDDLE;

  2168.         s->in_cubemap_face_order[BACK]  = BOTTOM_MIDDLE;

  2169.     }

  2170. 

  2171.     if (s->iv_flip) {

  2172.         s->in_cubemap_face_rotation[TOP_LEFT]      = ROT_270;

  2173.         s->in_cubemap_face_rotation[TOP_MIDDLE]    = ROT_90;

  2174.         s->in_cubemap_face_rotation[TOP_RIGHT]     = ROT_270;

  2175.         s->in_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_0;

  2176.         s->in_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_0;

  2177.         s->in_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_0;

  2178.     } else {

  2179.         s->in_cubemap_face_rotation[TOP_LEFT]      = ROT_0;

  2180.         s->in_cubemap_face_rotation[TOP_MIDDLE]    = ROT_0;

  2181.         s->in_cubemap_face_rotation[TOP_RIGHT]     = ROT_0;

  2182.         s->in_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_270;

  2183.         s->in_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_90;

  2184.         s->in_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_270;

  2185.     }

  2186. 

  2187.     return 0;

  2188. }

  2189. 

  2190. /**

  2191.  * Prepare data for processing equi-angular cubemap output format.

  2192.  *

  2193.  * @param ctx filter context

  2194.  *

  2195.  * @return error code

  2196.  */

  2197. static int prepare_eac_out(AVFilterContext *ctx)

  2198. {

  2199.     V360Context *s = ctx->priv;

  2200. 

  2201.     s->out_cubemap_direction_order[TOP_LEFT]      = LEFT;

  2202.     s->out_cubemap_direction_order[TOP_MIDDLE]    = FRONT;

  2203.     s->out_cubemap_direction_order[TOP_RIGHT]     = RIGHT;

  2204.     s->out_cubemap_direction_order[BOTTOM_LEFT]   = DOWN;

  2205.     s->out_cubemap_direction_order[BOTTOM_MIDDLE] = BACK;

  2206.     s->out_cubemap_direction_order[BOTTOM_RIGHT]  = UP;

  2207. 

  2208.     s->out_cubemap_face_rotation[TOP_LEFT]      = ROT_0;

  2209.     s->out_cubemap_face_rotation[TOP_MIDDLE]    = ROT_0;

  2210.     s->out_cubemap_face_rotation[TOP_RIGHT]     = ROT_0;

  2211.     s->out_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_270;

  2212.     s->out_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_90;

  2213.     s->out_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_270;

  2214. 

  2215.     return 0;

  2216. }

  2217. 

  2218. /**

  2219.  * Calculate 3D coordinates on sphere for corresponding frame position in equi-angular cubemap format.

  2220.  *

  2221.  * @param s filter private context

  2222.  * @param i horizontal position on frame [0, width)

  2223.  * @param j vertical position on frame [0, height)

  2224.  * @param width frame width

  2225.  * @param height frame height

  2226.  * @param vec coordinates on sphere

  2227.  */

  2228. static int eac_to_xyz(const V360Context *s,

  2229.                       int i, int j, int width, int height,

  2230.                       float *vec)

  2231. {

  2232.     const float pixel_pad = 2;

  2233.     const float u_pad = pixel_pad / width;

  2234.     const float v_pad = pixel_pad / height;

  2235. 

  2236.     int u_face, v_face, face;

  2237. 

  2238.     float l_x, l_y, l_z;

  2239. 

  2240.     float uf = (i + 0.5f) / width;

  2241.     float vf = (j + 0.5f) / height;

  2242. 

  2243.     // EAC has 2-pixel padding on faces except between faces on the same row

  2244.     // Padding pixels seems not to be stretched with tangent as regular pixels

  2245.     // Formulas below approximate original padding as close as I could get experimentally

  2246. 

  2247.     // Horizontal padding

  2248.     uf = 3.f * (uf - u_pad) / (1.f - 2.f * u_pad);

  2249.     if (uf < 0.f) {

  2250.         u_face = 0;

  2251.         uf -= 0.5f;

  2252.     } else if (uf >= 3.f) {

  2253.         u_face = 2;

  2254.         uf -= 2.5f;

  2255.     } else {

  2256.         u_face = floorf(uf);

  2257.         uf = fmodf(uf, 1.f) - 0.5f;

  2258.     }

  2259. 

  2260.     // Vertical padding

  2261.     v_face = floorf(vf * 2.f);

  2262.     vf = (vf - v_pad - 0.5f * v_face) / (0.5f - 2.f * v_pad) - 0.5f;

  2263. 

  2264.     if (uf >= -0.5f && uf < 0.5f) {

  2265.         uf = tanf(M_PI_2 * uf);

  2266.     } else {

  2267.         uf = 2.f * uf;

  2268.     }

  2269.     if (vf >= -0.5f && vf < 0.5f) {

  2270.         vf = tanf(M_PI_2 * vf);

  2271.     } else {

  2272.         vf = 2.f * vf;

  2273.     }

  2274. 

  2275.     face = u_face + 3 * v_face;

  2276. 

  2277.     switch (face) {

  2278.     case TOP_LEFT:

  2279.         l_x = -1.f;

  2280.         l_y = -vf;

  2281.         l_z = -uf;

  2282.         break;

  2283.     case TOP_MIDDLE:

  2284.         l_x =  uf;

  2285.         l_y = -vf;

  2286.         l_z = -1.f;

  2287.         break;

  2288.     case TOP_RIGHT:

  2289.         l_x =  1.f;

  2290.         l_y = -vf;

  2291.         l_z =  uf;

  2292.         break;

  2293.     case BOTTOM_LEFT:

  2294.         l_x = -vf;

  2295.         l_y = -1.f;

  2296.         l_z =  uf;

  2297.         break;

  2298.     case BOTTOM_MIDDLE:

  2299.         l_x = -vf;

  2300.         l_y =  uf;

  2301.         l_z =  1.f;

  2302.         break;

  2303.     case BOTTOM_RIGHT:

  2304.         l_x = -vf;

  2305.         l_y =  1.f;

  2306.         l_z = -uf;

  2307.         break;

  2308.     default:

  2309.         av_assert0(0);

  2310.     }

  2311. 

  2312.     vec[0] = l_x;

  2313.     vec[1] = l_y;

  2314.     vec[2] = l_z;

  2315. 

  2316.     normalize_vector(vec);

  2317. 

  2318.     return 1;

  2319. }

  2320. 

  2321. /**

  2322.  * Calculate frame position in equi-angular cubemap format for corresponding 3D coordinates on sphere.

  2323.  *

  2324.  * @param s filter private context

  2325.  * @param vec coordinates on sphere

  2326.  * @param width frame width

  2327.  * @param height frame height

  2328.  * @param us horizontal coordinates for interpolation window

  2329.  * @param vs vertical coordinates for interpolation window

  2330.  * @param du horizontal relative coordinate

  2331.  * @param dv vertical relative coordinate

  2332.  */

  2333. static int xyz_to_eac(const V360Context *s,

  2334.                       const float *vec, int width, int height,

  2335.                       int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2336. {

  2337.     const float pixel_pad = 2;

  2338.     const float u_pad = pixel_pad / width;

  2339.     const float v_pad = pixel_pad / height;

  2340. 

  2341.     float uf, vf;

  2342.     int ui, vi;

  2343.     int direction, face;

  2344.     int u_face, v_face;

  2345. 

  2346.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  2347. 

  2348.     face = s->in_cubemap_face_order[direction];

  2349.     u_face = face % 3;

  2350.     v_face = face / 3;

  2351. 

  2352.     uf = M_2_PI * atanf(uf) + 0.5f;

  2353.     vf = M_2_PI * atanf(vf) + 0.5f;

  2354. 

  2355.     // These formulas are inversed from eac_to_xyz ones

  2356.     uf = (uf + u_face) * (1.f - 2.f * u_pad) / 3.f + u_pad;

  2357.     vf = vf * (0.5f - 2.f * v_pad) + v_pad + 0.5f * v_face;

  2358. 

  2359.     uf *= width;

  2360.     vf *= height;

  2361. 

  2362.     uf -= 0.5f;

  2363.     vf -= 0.5f;

  2364. 

  2365.     ui = floorf(uf);

  2366.     vi = floorf(vf);

  2367. 

  2368.     *du = uf - ui;

  2369.     *dv = vf - vi;

  2370. 

  2371.     for (int i = 0; i < 4; i++) {

  2372.         for (int j = 0; j < 4; j++) {

  2373.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2374.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2375.         }

  2376.     }

  2377. 

  2378.     return 1;

  2379. }

  2380. 

  2381. /**

  2382.  * Prepare data for processing flat output format.

  2383.  *

  2384.  * @param ctx filter context

  2385.  *

  2386.  * @return error code

  2387.  */

  2388. static int prepare_flat_out(AVFilterContext *ctx)

  2389. {

  2390.     V360Context *s = ctx->priv;

  2391. 

  2392.     s->flat_range[0] = tanf(0.5f * s->h_fov * M_PI / 180.f);

  2393.     s->flat_range[1] = tanf(0.5f * s->v_fov * M_PI / 180.f);

  2394. 

  2395.     return 0;

  2396. }

  2397. 

  2398. /**

  2399.  * Calculate 3D coordinates on sphere for corresponding frame position in flat format.

  2400.  *

  2401.  * @param s filter private context

  2402.  * @param i horizontal position on frame [0, width)

  2403.  * @param j vertical position on frame [0, height)

  2404.  * @param width frame width

  2405.  * @param height frame height

  2406.  * @param vec coordinates on sphere

  2407.  */

  2408. static int flat_to_xyz(const V360Context *s,

  2409.                        int i, int j, int width, int height,

  2410.                        float *vec)

  2411. {

  2412.     const float l_x =  s->flat_range[0] * ((2.f * i + 0.5f) / width  - 1.f);

  2413.     const float l_y = -s->flat_range[1] * ((2.f * j + 0.5f) / height - 1.f);

  2414. 

  2415.     vec[0] =  l_x;

  2416.     vec[1] =  l_y;

  2417.     vec[2] = -1.f;

  2418. 

  2419.     normalize_vector(vec);

  2420. 

  2421.     return 1;

  2422. }

  2423. 

  2424. /**

  2425.  * Prepare data for processing fisheye output format.

  2426.  *

  2427.  * @param ctx filter context

  2428.  *

  2429.  * @return error code

  2430.  */

  2431. static int prepare_fisheye_out(AVFilterContext *ctx)

  2432. {

  2433.     V360Context *s = ctx->priv;

  2434. 

  2435.     s->flat_range[0] = s->h_fov / 180.f;

  2436.     s->flat_range[1] = s->v_fov / 180.f;

  2437. 

  2438.     return 0;

  2439. }

  2440. 

  2441. /**

  2442.  * Calculate 3D coordinates on sphere for corresponding frame position in fisheye format.

  2443.  *

  2444.  * @param s filter private context

  2445.  * @param i horizontal position on frame [0, width)

  2446.  * @param j vertical position on frame [0, height)

  2447.  * @param width frame width

  2448.  * @param height frame height

  2449.  * @param vec coordinates on sphere

  2450.  */

  2451. static int fisheye_to_xyz(const V360Context *s,

  2452.                           int i, int j, int width, int height,

  2453.                           float *vec)

  2454. {

  2455.     const float uf = s->flat_range[0] * ((2.f * i) / width  - 1.f);

  2456.     const float vf = s->flat_range[1] * ((2.f * j + 1.f) / height - 1.f);

  2457. 

  2458.     const float phi   = -atan2f(vf, uf);

  2459.     const float theta = -M_PI_2 * (1.f - hypotf(uf, vf));

  2460. 

  2461.     vec[0] = cosf(theta) * cosf(phi);

  2462.     vec[1] = cosf(theta) * sinf(phi);

  2463.     vec[2] = sinf(theta);

  2464. 

  2465.     normalize_vector(vec);

  2466. 

  2467.     return 1;

  2468. }

  2469. 

  2470. /**

  2471.  * Prepare data for processing fisheye input format.

  2472.  *

  2473.  * @param ctx filter context

  2474.  *

  2475.  * @return error code

  2476.  */

  2477. static int prepare_fisheye_in(AVFilterContext *ctx)

  2478. {

  2479.     V360Context *s = ctx->priv;

  2480. 

  2481.     s->iflat_range[0] = s->ih_fov / 180.f;

  2482.     s->iflat_range[1] = s->iv_fov / 180.f;

  2483. 

  2484.     return 0;

  2485. }

  2486. 

  2487. /**

  2488.  * Calculate frame position in fisheye format for corresponding 3D coordinates on sphere.

  2489.  *

  2490.  * @param s filter private context

  2491.  * @param vec coordinates on sphere

  2492.  * @param width frame width

  2493.  * @param height frame height

  2494.  * @param us horizontal coordinates for interpolation window

  2495.  * @param vs vertical coordinates for interpolation window

  2496.  * @param du horizontal relative coordinate

  2497.  * @param dv vertical relative coordinate

  2498.  */

  2499. static int xyz_to_fisheye(const V360Context *s,

  2500.                           const float *vec, int width, int height,

  2501.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2502. {

  2503.     const float h   = hypotf(vec[0], vec[1]);

  2504.     const float lh  = h > 0.f ? h : 1.f;

  2505.     const float phi = atan2f(h, -vec[2]) / M_PI;

  2506. 

  2507.     float uf =  vec[0] / lh * phi * s->input_mirror_modifier[0] / s->iflat_range[0];

  2508.     float vf = -vec[1] / lh * phi * s->input_mirror_modifier[1] / s->iflat_range[1];

  2509. 

  2510.     const int visible = hypotf(uf, vf) <= 0.5f;

  2511.     int ui, vi;

  2512. 

  2513.     uf = (uf + 0.5f) * width;

  2514.     vf = (vf + 0.5f) * height;

  2515. 

  2516.     ui = floorf(uf);

  2517.     vi = floorf(vf);

  2518. 

  2519.     *du = visible ? uf - ui : 0.f;

  2520.     *dv = visible ? vf - vi : 0.f;

  2521. 

  2522.     for (int i = 0; i < 4; i++) {

  2523.         for (int j = 0; j < 4; j++) {

  2524.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  2525.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  2526.         }

  2527.     }

  2528. 

  2529.     return visible;

  2530. }

  2531. 

  2532. /**

  2533.  * Calculate 3D coordinates on sphere for corresponding frame position in pannini format.

  2534.  *

  2535.  * @param s filter private context

  2536.  * @param i horizontal position on frame [0, width)

  2537.  * @param j vertical position on frame [0, height)

  2538.  * @param width frame width

  2539.  * @param height frame height

  2540.  * @param vec coordinates on sphere

  2541.  */

  2542. static int pannini_to_xyz(const V360Context *s,

  2543.                           int i, int j, int width, int height,

  2544.                           float *vec)

  2545. {

  2546.     const float uf = ((2.f * i + 1.f) / width  - 1.f);

  2547.     const float vf = ((2.f * j + 1.f) / height - 1.f);

  2548. 

  2549.     const float d = s->h_fov;

  2550.     const float k = uf * uf / ((d + 1.f) * (d + 1.f));

  2551.     const float dscr = k * k * d * d - (k + 1.f) * (k * d * d - 1.f);

  2552.     const float clon = (-k * d + sqrtf(dscr)) / (k + 1.f);

  2553.     const float S = (d + 1.f) / (d + clon);

  2554.     const float lon = -(M_PI + atan2f(uf, S * clon));

  2555.     const float lat = -atan2f(vf, S);

  2556. 

  2557.     vec[0] = sinf(lon) * cosf(lat);

  2558.     vec[1] = sinf(lat);

  2559.     vec[2] = cosf(lon) * cosf(lat);

  2560. 

  2561.     normalize_vector(vec);

  2562. 

  2563.     return 1;

  2564. }

  2565. 

  2566. /**

  2567.  * Prepare data for processing cylindrical output format.

  2568.  *

  2569.  * @param ctx filter context

  2570.  *

  2571.  * @return error code

  2572.  */

  2573. static int prepare_cylindrical_out(AVFilterContext *ctx)

  2574. {

  2575.     V360Context *s = ctx->priv;

  2576. 

  2577.     s->flat_range[0] = M_PI * s->h_fov / 360.f;

  2578.     s->flat_range[1] = tanf(0.5f * s->v_fov * M_PI / 180.f);

  2579. 

  2580.     return 0;

  2581. }

  2582. 

  2583. /**

  2584.  * Calculate 3D coordinates on sphere for corresponding frame position in cylindrical format.

  2585.  *

  2586.  * @param s filter private context

  2587.  * @param i horizontal position on frame [0, width)

  2588.  * @param j vertical position on frame [0, height)

  2589.  * @param width frame width

  2590.  * @param height frame height

  2591.  * @param vec coordinates on sphere

  2592.  */

  2593. static int cylindrical_to_xyz(const V360Context *s,

  2594.                               int i, int j, int width, int height,

  2595.                               float *vec)

  2596. {

  2597.     const float uf = s->flat_range[0] * ((2.f * i + 1.f) / width  - 1.f);

  2598.     const float vf = s->flat_range[1] * ((2.f * j + 1.f) / height - 1.f);

  2599. 

  2600.     const float phi   = uf;

  2601.     const float theta = atanf(vf);

  2602. 

  2603.     const float sin_phi   = sinf(phi);

  2604.     const float cos_phi   = cosf(phi);

  2605.     const float sin_theta = sinf(theta);

  2606.     const float cos_theta = cosf(theta);

  2607. 

  2608.     vec[0] =  cos_theta * sin_phi;

  2609.     vec[1] = -sin_theta;

  2610.     vec[2] = -cos_theta * cos_phi;

  2611. 

  2612.     normalize_vector(vec);

  2613. 

  2614.     return 1;

  2615. }

  2616. 

  2617. /**

  2618.  * Prepare data for processing cylindrical input format.

  2619.  *

  2620.  * @param ctx filter context

  2621.  *

  2622.  * @return error code

  2623.  */

  2624. static int prepare_cylindrical_in(AVFilterContext *ctx)

  2625. {

  2626.     V360Context *s = ctx->priv;

  2627. 

  2628.     s->iflat_range[0] = M_PI * s->ih_fov / 360.f;

  2629.     s->iflat_range[1] = tanf(0.5f * s->iv_fov * M_PI / 180.f);

  2630. 

  2631.     return 0;

  2632. }

  2633. 

  2634. /**

  2635.  * Calculate frame position in cylindrical format for corresponding 3D coordinates on sphere.

  2636.  *

  2637.  * @param s filter private context

  2638.  * @param vec coordinates on sphere

  2639.  * @param width frame width

  2640.  * @param height frame height

  2641.  * @param us horizontal coordinates for interpolation window

  2642.  * @param vs vertical coordinates for interpolation window

  2643.  * @param du horizontal relative coordinate

  2644.  * @param dv vertical relative coordinate

  2645.  */

  2646. static int xyz_to_cylindrical(const V360Context *s,

  2647.                               const float *vec, int width, int height,

  2648.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2649. {

  2650.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0] / s->iflat_range[0];

  2651.     const float theta = atan2f(-vec[1], hypotf(vec[0], vec[2])) * s->input_mirror_modifier[1] / s->iflat_range[1];

  2652.     int visible, ui, vi;

  2653.     float uf, vf;

  2654. 

  2655.     uf = (phi + 1.f) * (width - 1) / 2.f;

  2656.     vf = (tanf(theta) + 1.f) * height / 2.f;

  2657.     ui = floorf(uf);

  2658.     vi = floorf(vf);

  2659. 

  2660.     visible = vi >= 0 && vi < height && ui >= 0 && ui < width &&

  2661.               theta <=  M_PI * s->iv_fov / 180.f &&

  2662.               theta >= -M_PI * s->iv_fov / 180.f;

  2663. 

  2664.     *du = uf - ui;

  2665.     *dv = vf - vi;

  2666. 

  2667.     for (int i = 0; i < 4; i++) {

  2668.         for (int j = 0; j < 4; j++) {

  2669.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  2670.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  2671.         }

  2672.     }

  2673. 

  2674.     return visible;

  2675. }

  2676. 

  2677. /**

  2678.  * Calculate 3D coordinates on sphere for corresponding frame position in perspective format.

  2679.  *

  2680.  * @param s filter private context

  2681.  * @param i horizontal position on frame [0, width)

  2682.  * @param j vertical position on frame [0, height)

  2683.  * @param width frame width

  2684.  * @param height frame height

  2685.  * @param vec coordinates on sphere

  2686.  */

  2687. static int perspective_to_xyz(const V360Context *s,

  2688.                               int i, int j, int width, int height,

  2689.                               float *vec)

  2690. {

  2691.     const float uf = ((2.f * i + 1.f) / width  - 1.f);

  2692.     const float vf = ((2.f * j + 1.f) / height - 1.f);

  2693.     const float rh = hypotf(uf, vf);

  2694.     const float sinzz = 1.f - rh * rh;

  2695.     const float h = 1.f + s->v_fov;

  2696.     const float sinz = (h - sqrtf(sinzz)) / (h / rh + rh / h);

  2697.     const float sinz2 = sinz * sinz;

  2698. 

  2699.     if (sinz2 <= 1.f) {

  2700.         const float cosz = sqrtf(1.f - sinz2);

  2701. 

  2702.         const float theta = asinf(cosz);

  2703.         const float phi   = atan2f(uf, vf);

  2704. 

  2705.         const float sin_phi   = sinf(phi);

  2706.         const float cos_phi   = cosf(phi);

  2707.         const float sin_theta = sinf(theta);

  2708.         const float cos_theta = cosf(theta);

  2709. 

  2710.         vec[0] =  cos_theta * sin_phi;

  2711.         vec[1] =  sin_theta;

  2712.         vec[2] = -cos_theta * cos_phi;

  2713.     } else {

  2714.         vec[0] =  0.f;

  2715.         vec[1] = -1.f;

  2716.         vec[2] =  0.f;

  2717.         return 0;

  2718.     }

  2719. 

  2720.     normalize_vector(vec);

  2721.     return 1;

  2722. }

  2723. 

  2724. /**

  2725.  * Calculate 3D coordinates on sphere for corresponding frame position in tetrahedron format.

  2726.  *

  2727.  * @param s filter private context

  2728.  * @param i horizontal position on frame [0, width)

  2729.  * @param j vertical position on frame [0, height)

  2730.  * @param width frame width

  2731.  * @param height frame height

  2732.  * @param vec coordinates on sphere

  2733.  */

  2734. static int tetrahedron_to_xyz(const V360Context *s,

  2735.                               int i, int j, int width, int height,

  2736.                               float *vec)

  2737. {

  2738.     const float uf = (float)i / width;

  2739.     const float vf = (float)j / height;

  2740. 

  2741.     vec[0] = uf < 0.5f ? uf * 4.f - 1.f : 3.f - uf * 4.f;

  2742.     vec[1] = 1.f - vf * 2.f;

  2743.     vec[2] = 2.f * fabsf(1.f - fabsf(1.f - uf * 2.f + vf)) - 1.f;

  2744. 

  2745.     normalize_vector(vec);

  2746. 

  2747.     return 1;

  2748. }

  2749. 

  2750. /**

  2751.  * Calculate frame position in tetrahedron format for corresponding 3D coordinates on sphere.

  2752.  *

  2753.  * @param s filter private context

  2754.  * @param vec coordinates on sphere

  2755.  * @param width frame width

  2756.  * @param height frame height

  2757.  * @param us horizontal coordinates for interpolation window

  2758.  * @param vs vertical coordinates for interpolation window

  2759.  * @param du horizontal relative coordinate

  2760.  * @param dv vertical relative coordinate

  2761.  */

  2762. static int xyz_to_tetrahedron(const V360Context *s,

  2763.                               const float *vec, int width, int height,

  2764.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2765. {

  2766.     const float d0 = vec[0] * 1.f + vec[1] * 1.f + vec[2] *-1.f;

  2767.     const float d1 = vec[0] *-1.f + vec[1] *-1.f + vec[2] *-1.f;

  2768.     const float d2 = vec[0] * 1.f + vec[1] *-1.f + vec[2] * 1.f;

  2769.     const float d3 = vec[0] *-1.f + vec[1] * 1.f + vec[2] * 1.f;

  2770.     const float d = FFMAX(d0, FFMAX3(d1, d2, d3));

  2771. 

  2772.     float uf, vf, x, y, z;

  2773.     int ui, vi;

  2774. 

  2775.     x =  vec[0] / d;

  2776.     y =  vec[1] / d;

  2777.     z = -vec[2] / d;

  2778. 

  2779.     vf = 0.5f - y * 0.5f * s->input_mirror_modifier[1];

  2780. 

  2781.     if ((x + y >= 0.f &&  y + z >= 0.f && -z - x <= 0.f) ||

  2782.         (x + y <= 0.f && -y + z >= 0.f &&  z - x >= 0.f)) {

  2783.         uf = 0.25f * x * s->input_mirror_modifier[0] + 0.25f;

  2784.     }  else {

  2785.         uf = 0.75f - 0.25f * x * s->input_mirror_modifier[0];

  2786.     }

  2787. 

  2788.     uf *= width;

  2789.     vf *= height;

  2790. 

  2791.     ui = floorf(uf);

  2792.     vi = floorf(vf);

  2793. 

  2794.     *du = uf - ui;

  2795.     *dv = vf - vi;

  2796. 

  2797.     for (int i = 0; i < 4; i++) {

  2798.         for (int j = 0; j < 4; j++) {

  2799.             us[i][j] = reflectx(ui + j - 1, vi + i - 1, width, height);

  2800.             vs[i][j] = reflecty(vi + i - 1, height);

  2801.         }

  2802.     }

  2803. 

  2804.     return 1;

  2805. }

  2806. 

  2807. /**

  2808.  * Calculate 3D coordinates on sphere for corresponding frame position in dual fisheye format.

  2809.  *

  2810.  * @param s filter private context

  2811.  * @param i horizontal position on frame [0, width)

  2812.  * @param j vertical position on frame [0, height)

  2813.  * @param width frame width

  2814.  * @param height frame height

  2815.  * @param vec coordinates on sphere

  2816.  */

  2817. static int dfisheye_to_xyz(const V360Context *s,

  2818.                            int i, int j, int width, int height,

  2819.                            float *vec)

  2820. {

  2821.     const float scale = 1.f + s->out_pad;

  2822. 

  2823.     const float ew = width / 2.f;

  2824.     const float eh = height;

  2825. 

  2826.     const int ei = i >= ew ? i - ew : i;

  2827.     const float m = i >= ew ? -1.f : 1.f;

  2828. 

  2829.     const float uf = ((2.f * ei) / ew - 1.f) * scale;

  2830.     const float vf = ((2.f * j + 1.f) / eh - 1.f) * scale;

  2831. 

  2832.     const float h     = hypotf(uf, vf);

  2833.     const float lh    = h > 0.f ? h : 1.f;

  2834.     const float theta = m * M_PI_2 * (1.f - h);

  2835. 

  2836.     const float sin_theta = sinf(theta);

  2837.     const float cos_theta = cosf(theta);

  2838. 

  2839.     vec[0] = cos_theta * m * -uf / lh;

  2840.     vec[1] = cos_theta *     -vf / lh;

  2841.     vec[2] = sin_theta;

  2842. 

  2843.     normalize_vector(vec);

  2844. 

  2845.     return 1;

  2846. }

  2847. 

  2848. /**

  2849.  * Calculate frame position in dual fisheye format for corresponding 3D coordinates on sphere.

  2850.  *

  2851.  * @param s filter private context

  2852.  * @param vec coordinates on sphere

  2853.  * @param width frame width

  2854.  * @param height frame height

  2855.  * @param us horizontal coordinates for interpolation window

  2856.  * @param vs vertical coordinates for interpolation window

  2857.  * @param du horizontal relative coordinate

  2858.  * @param dv vertical relative coordinate

  2859.  */

  2860. static int xyz_to_dfisheye(const V360Context *s,

  2861.                            const float *vec, int width, int height,

  2862.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2863. {

  2864.     const float scale = 1.f - s->in_pad;

  2865. 

  2866.     const float ew = width / 2.f;

  2867.     const float eh = height;

  2868. 

  2869.     const float h     = hypotf(vec[0], vec[1]);

  2870.     const float lh    = h > 0.f ? h : 1.f;

  2871.     const float theta = acosf(fabsf(vec[2])) / M_PI;

  2872. 

  2873.     float uf = (theta * (-vec[0] / lh) * s->input_mirror_modifier[0] * scale + 0.5f) * ew;

  2874.     float vf = (theta * (-vec[1] / lh) * s->input_mirror_modifier[1] * scale + 0.5f) * eh;

  2875. 

  2876.     int ui, vi;

  2877.     int u_shift;

  2878. 

  2879.     if (vec[2] >= 0.f) {

  2880.         u_shift = 0;

  2881.     } else {

  2882.         u_shift = ceilf(ew);

  2883.         uf = ew - uf;

  2884.     }

  2885. 

  2886.     ui = floorf(uf);

  2887.     vi = floorf(vf);

  2888. 

  2889.     *du = uf - ui;

  2890.     *dv = vf - vi;

  2891. 

  2892.     for (int i = 0; i < 4; i++) {

  2893.         for (int j = 0; j < 4; j++) {

  2894.             us[i][j] = av_clip(u_shift + ui + j - 1, 0, width  - 1);

  2895.             vs[i][j] = av_clip(          vi + i - 1, 0, height - 1);

  2896.         }

  2897.     }

  2898. 

  2899.     return 1;

  2900. }

  2901. 

  2902. /**

  2903.  * Calculate 3D coordinates on sphere for corresponding frame position in barrel facebook's format.

  2904.  *

  2905.  * @param s filter private context

  2906.  * @param i horizontal position on frame [0, width)

  2907.  * @param j vertical position on frame [0, height)

  2908.  * @param width frame width

  2909.  * @param height frame height

  2910.  * @param vec coordinates on sphere

  2911.  */

  2912. static int barrel_to_xyz(const V360Context *s,

  2913.                          int i, int j, int width, int height,

  2914.                          float *vec)

  2915. {

  2916.     const float scale = 0.99f;

  2917.     float l_x, l_y, l_z;

  2918. 

  2919.     if (i < 4 * width / 5) {

  2920.         const float theta_range = M_PI_4;

  2921. 

  2922.         const int ew = 4 * width / 5;

  2923.         const int eh = height;

  2924. 

  2925.         const float phi   = ((2.f * i) / ew - 1.f) * M_PI        / scale;

  2926.         const float theta = ((2.f * j) / eh - 1.f) * theta_range / scale;

  2927. 

  2928.         const float sin_phi   = sinf(phi);

  2929.         const float cos_phi   = cosf(phi);

  2930.         const float sin_theta = sinf(theta);

  2931.         const float cos_theta = cosf(theta);

  2932. 

  2933.         l_x =  cos_theta * sin_phi;

  2934.         l_y = -sin_theta;

  2935.         l_z = -cos_theta * cos_phi;

  2936.     } else {

  2937.         const int ew = width  / 5;

  2938.         const int eh = height / 2;

  2939. 

  2940.         float uf, vf;

  2941. 

  2942.         if (j < eh) {   // UP

  2943.             uf = 2.f * (i - 4 * ew) / ew - 1.f;

  2944.             vf = 2.f * (j         ) / eh - 1.f;

  2945. 

  2946.             uf /= scale;

  2947.             vf /= scale;

  2948. 

  2949.             l_x =  uf;

  2950.             l_y =  1.f;

  2951.             l_z = -vf;

  2952.         } else {            // DOWN

  2953.             uf = 2.f * (i - 4 * ew) / ew - 1.f;

  2954.             vf = 2.f * (j -     eh) / eh - 1.f;

  2955. 

  2956.             uf /= scale;

  2957.             vf /= scale;

  2958. 

  2959.             l_x =  uf;

  2960.             l_y = -1.f;

  2961.             l_z =  vf;

  2962.         }

  2963.     }

  2964. 

  2965.     vec[0] = l_x;

  2966.     vec[1] = l_y;

  2967.     vec[2] = l_z;

  2968. 

  2969.     normalize_vector(vec);

  2970. 

  2971.     return 1;

  2972. }

  2973. 

  2974. /**

  2975.  * Calculate frame position in barrel facebook's format for corresponding 3D coordinates on sphere.

  2976.  *

  2977.  * @param s filter private context

  2978.  * @param vec coordinates on sphere

  2979.  * @param width frame width

  2980.  * @param height frame height

  2981.  * @param us horizontal coordinates for interpolation window

  2982.  * @param vs vertical coordinates for interpolation window

  2983.  * @param du horizontal relative coordinate

  2984.  * @param dv vertical relative coordinate

  2985.  */

  2986. static int xyz_to_barrel(const V360Context *s,

  2987.                          const float *vec, int width, int height,

  2988.                          int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2989. {

  2990.     const float scale = 0.99f;

  2991. 

  2992.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  2993.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  2994.     const float theta_range = M_PI_4;

  2995. 

  2996.     int ew, eh;

  2997.     int u_shift, v_shift;

  2998.     float uf, vf;

  2999.     int ui, vi;

  3000. 

  3001.     if (theta > -theta_range && theta < theta_range) {

  3002.         ew = 4 * width / 5;

  3003.         eh = height;

  3004. 

  3005.         u_shift = s->ih_flip ? width / 5 : 0;

  3006.         v_shift = 0;

  3007. 

  3008.         uf = (phi   / M_PI        * scale + 1.f) * ew / 2.f;

  3009.         vf = (theta / theta_range * scale + 1.f) * eh / 2.f;

  3010.     } else {

  3011.         ew = width  / 5;

  3012.         eh = height / 2;

  3013. 

  3014.         u_shift = s->ih_flip ? 0 : 4 * ew;

  3015. 

  3016.         if (theta < 0.f) {  // UP

  3017.             uf =  vec[0] / vec[1];

  3018.             vf = -vec[2] / vec[1];

  3019.             v_shift = 0;

  3020.         } else {            // DOWN

  3021.             uf = -vec[0] / vec[1];

  3022.             vf = -vec[2] / vec[1];

  3023.             v_shift = eh;

  3024.         }

  3025. 

  3026.         uf *= s->input_mirror_modifier[0] * s->input_mirror_modifier[1];

  3027.         vf *= s->input_mirror_modifier[1];

  3028. 

  3029.         uf = 0.5f * ew * (uf * scale + 1.f);

  3030.         vf = 0.5f * eh * (vf * scale + 1.f);

  3031.     }

  3032. 

  3033.     ui = floorf(uf);

  3034.     vi = floorf(vf);

  3035. 

  3036.     *du = uf - ui;

  3037.     *dv = vf - vi;

  3038. 

  3039.     for (int i = 0; i < 4; i++) {

  3040.         for (int j = 0; j < 4; j++) {

  3041.             us[i][j] = u_shift + av_clip(ui + j - 1, 0, ew - 1);

  3042.             vs[i][j] = v_shift + av_clip(vi + i - 1, 0, eh - 1);

  3043.         }

  3044.     }

  3045. 

  3046.     return 1;

  3047. }

  3048. 

  3049. /**

  3050.  * Calculate frame position in barrel split facebook's format for corresponding 3D coordinates on sphere.

  3051.  *

  3052.  * @param s filter private context

  3053.  * @param vec coordinates on sphere

  3054.  * @param width frame width

  3055.  * @param height frame height

  3056.  * @param us horizontal coordinates for interpolation window

  3057.  * @param vs vertical coordinates for interpolation window

  3058.  * @param du horizontal relative coordinate

  3059.  * @param dv vertical relative coordinate

  3060.  */

  3061. static int xyz_to_barrelsplit(const V360Context *s,

  3062.                               const float *vec, int width, int height,

  3063.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  3064. {

  3065.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  3066.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  3067. 

  3068.     const float theta_range = M_PI_4;

  3069. 

  3070.     int ew, eh;

  3071.     int u_shift, v_shift;

  3072.     float uf, vf;

  3073.     int ui, vi;

  3074. 

  3075.     if (theta >= -theta_range && theta <= theta_range) {

  3076.         const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (width * 2.f / 3.f) : 1.f - s->in_pad;

  3077.         const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (height / 2.f) : 1.f - s->in_pad;

  3078. 

  3079.         ew = width / 3 * 2;

  3080.         eh = height / 2;

  3081. 

  3082.         u_shift = s->ih_flip ? width / 3 : 0;

  3083.         v_shift = phi >= M_PI_2 || phi < -M_PI_2 ? eh : 0;

  3084. 

  3085.         uf = fmodf(phi, M_PI_2) / M_PI_2;

  3086.         vf = theta / M_PI_4;

  3087. 

  3088.         if (v_shift)

  3089.             uf = uf >= 0.f ? fmodf(uf - 1.f, 1.f) : fmodf(uf + 1.f, 1.f);

  3090. 

  3091.         uf = (uf * scalew + 1.f) * width  / 3.f;

  3092.         vf = (vf * scaleh + 1.f) * height / 4.f;

  3093.     } else {

  3094.         const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (width  / 3.f) : 1.f - s->in_pad;

  3095.         const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (height / 4.f) : 1.f - s->in_pad;

  3096.         int v_offset = 0;

  3097. 

  3098.         ew = width  / 3;

  3099.         eh = height / 4;

  3100. 

  3101.         u_shift = s->ih_flip ? 0 : 2 * ew;

  3102. 

  3103.         if (theta <= 0.f && theta >= -M_PI_2 &&

  3104.             phi <= M_PI_2 && phi >= -M_PI_2) {

  3105.             uf =  vec[0] / vec[1];

  3106.             vf = -vec[2] / vec[1];

  3107.             v_shift = 0;

  3108.             v_offset = -eh;

  3109.         } else if (theta >= 0.f && theta <= M_PI_2 &&

  3110.                    phi <= M_PI_2 && phi >= -M_PI_2) {

  3111.             uf = -vec[0] / vec[1];

  3112.             vf = -vec[2] / vec[1];

  3113.             v_shift = height * 0.25f;

  3114.         } else if (theta <= 0.f && theta >= -M_PI_2) {

  3115.             uf = -vec[0] / vec[1];

  3116.             vf =  vec[2] / vec[1];

  3117.             v_shift = height * 0.5f;

  3118.             v_offset = -eh;

  3119.         } else {

  3120.             uf = vec[0] / vec[1];

  3121.             vf = vec[2] / vec[1];

  3122.             v_shift = height * 0.75f;

  3123.         }

  3124. 

  3125.         uf *= s->input_mirror_modifier[0] * s->input_mirror_modifier[1];

  3126.         vf *= s->input_mirror_modifier[1];

  3127. 

  3128.         uf = 0.5f * width / 3.f * (uf * scalew + 1.f);

  3129.         vf = height * 0.25f * (vf * scaleh + 1.f) + v_offset;

  3130.     }

  3131. 

  3132.     ui = floorf(uf);

  3133.     vi = floorf(vf);

  3134. 

  3135.     *du = uf - ui;

  3136.     *dv = vf - vi;

  3137. 

  3138.     for (int i = 0; i < 4; i++) {

  3139.         for (int j = 0; j < 4; j++) {

  3140.             us[i][j] = u_shift + av_clip(ui + j - 1, 0, ew - 1);

  3141.             vs[i][j] = v_shift + av_clip(vi + i - 1, 0, eh - 1);

  3142.         }

  3143.     }

  3144. 

  3145.     return 1;

  3146. }

  3147. 

  3148. /**

  3149.  * Calculate 3D coordinates on sphere for corresponding frame position in barrel split facebook's format.

  3150.  *

  3151.  * @param s filter private context

  3152.  * @param i horizontal position on frame [0, width)

  3153.  * @param j vertical position on frame [0, height)

  3154.  * @param width frame width

  3155.  * @param height frame height

  3156.  * @param vec coordinates on sphere

  3157.  */

  3158. static int barrelsplit_to_xyz(const V360Context *s,

  3159.                               int i, int j, int width, int height,

  3160.                               float *vec)

  3161. {

  3162.     const float x = (i + 0.5f) / width;

  3163.     const float y = (j + 0.5f) / height;

  3164.     float l_x, l_y, l_z;

  3165. 

  3166.     if (x < 2.f / 3.f) {

  3167.         const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (width * 2.f / 3.f) : 1.f - s->out_pad;

  3168.         const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (height / 2.f) : 1.f - s->out_pad;

  3169. 

  3170.         const float back = floorf(y * 2.f);

  3171. 

  3172.         const float phi   = ((3.f / 2.f * x - 0.5f) / scalew - back + 1.f) * M_PI;

  3173.         const float theta = (y - 0.25f - 0.5f * back) / scaleh * M_PI;

  3174. 

  3175.         const float sin_phi   = sinf(phi);

  3176.         const float cos_phi   = cosf(phi);

  3177.         const float sin_theta = sinf(theta);

  3178.         const float cos_theta = cosf(theta);

  3179. 

  3180.         l_x = -cos_theta * sin_phi;

  3181.         l_y = -sin_theta;

  3182.         l_z =  cos_theta * cos_phi;

  3183.     } else {

  3184.         const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (width  / 3.f) : 1.f - s->out_pad;

  3185.         const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (height / 4.f) : 1.f - s->out_pad;

  3186. 

  3187.         const int face = floorf(y * 4.f);

  3188.         float uf, vf;

  3189. 

  3190.         uf = x * 3.f - 2.f;

  3191. 

  3192.         switch (face) {

  3193.         case 0:

  3194.             vf = y * 2.f;

  3195.             uf = 1.f - uf;

  3196.             vf = 0.5f - vf;

  3197. 

  3198.             l_x = (0.5f - uf) / scalew;

  3199.             l_y =  0.5f;

  3200.             l_z = (-0.5f + vf) / scaleh;

  3201.             break;

  3202.         case 1:

  3203.             vf = y * 2.f;

  3204.             uf = 1.f - uf;

  3205.             vf = 1.f - (vf - 0.5f);

  3206. 

  3207.             l_x = (0.5f - uf) / scalew;

  3208.             l_y = -0.5f;

  3209.             l_z = (0.5f - vf) / scaleh;

  3210.             break;

  3211.         case 2:

  3212.             vf = y * 2.f - 0.5f;

  3213.             vf = 1.f - (1.f - vf);

  3214. 

  3215.             l_x = (0.5f - uf) / scalew;

  3216.             l_y = 0.5f;

  3217.             l_z = (-0.5f + vf) / scaleh;

  3218.             break;

  3219.         case 3:

  3220.             vf = y * 2.f - 1.5f;

  3221. 

  3222.             l_x = (0.5f - uf) / scalew;

  3223.             l_y = -0.5f;

  3224.             l_z = (0.5f - vf) / scaleh;

  3225.             break;

  3226.         }

  3227.     }

  3228. 

  3229.     vec[0] = l_x;

  3230.     vec[1] = l_y;

  3231.     vec[2] = l_z;

  3232. 

  3233.     normalize_vector(vec);

  3234. 

  3235.     return 1;

  3236. }

  3237. 

  3238. static void multiply_matrix(float c[3][3], const float a[3][3], const float b[3][3])

  3239. {

  3240.     for (int i = 0; i < 3; i++) {

  3241.         for (int j = 0; j < 3; j++) {

  3242.             float sum = 0.f;

  3243. 

  3244.             for (int k = 0; k < 3; k++)

  3245.                 sum += a[i][k] * b[k][j];

  3246. 

  3247.             c[i][j] = sum;

  3248.         }

  3249.     }

  3250. }

  3251. 

  3252. /**

  3253.  * Calculate rotation matrix for yaw/pitch/roll angles.

  3254.  */

  3255. static inline void calculate_rotation_matrix(float yaw, float pitch, float roll,

  3256.                                              float rot_mat[3][3],

  3257.                                              const int rotation_order[3])

  3258. {

  3259.     const float yaw_rad   = yaw   * M_PI / 180.f;

  3260.     const float pitch_rad = pitch * M_PI / 180.f;

  3261.     const float roll_rad  = roll  * M_PI / 180.f;

  3262. 

  3263.     const float sin_yaw   = sinf(-yaw_rad);

  3264.     const float cos_yaw   = cosf(-yaw_rad);

  3265.     const float sin_pitch = sinf(pitch_rad);

  3266.     const float cos_pitch = cosf(pitch_rad);

  3267.     const float sin_roll  = sinf(roll_rad);

  3268.     const float cos_roll  = cosf(roll_rad);

  3269. 

  3270.     float m[3][3][3];

  3271.     float temp[3][3];

  3272. 

  3273.     m[0][0][0] =  cos_yaw;  m[0][0][1] = 0;          m[0][0][2] =  sin_yaw;

  3274.     m[0][1][0] =  0;        m[0][1][1] = 1;          m[0][1][2] =  0;

  3275.     m[0][2][0] = -sin_yaw;  m[0][2][1] = 0;          m[0][2][2] =  cos_yaw;

  3276. 

  3277.     m[1][0][0] = 1;         m[1][0][1] = 0;          m[1][0][2] =  0;

  3278.     m[1][1][0] = 0;         m[1][1][1] = cos_pitch;  m[1][1][2] = -sin_pitch;

  3279.     m[1][2][0] = 0;         m[1][2][1] = sin_pitch;  m[1][2][2] =  cos_pitch;

  3280. 

  3281.     m[2][0][0] = cos_roll;  m[2][0][1] = -sin_roll;  m[2][0][2] =  0;

  3282.     m[2][1][0] = sin_roll;  m[2][1][1] =  cos_roll;  m[2][1][2] =  0;

  3283.     m[2][2][0] = 0;         m[2][2][1] =  0;         m[2][2][2] =  1;

  3284. 

  3285.     multiply_matrix(temp, m[rotation_order[0]], m[rotation_order[1]]);

  3286.     multiply_matrix(rot_mat, temp, m[rotation_order[2]]);

  3287. }

  3288. 

  3289. /**

  3290.  * Rotate vector with given rotation matrix.

  3291.  *

  3292.  * @param rot_mat rotation matrix

  3293.  * @param vec vector

  3294.  */

  3295. static inline void rotate(const float rot_mat[3][3],

  3296.                           float *vec)

  3297. {

  3298.     const float x_tmp = vec[0] * rot_mat[0][0] + vec[1] * rot_mat[0][1] + vec[2] * rot_mat[0][2];

  3299.     const float y_tmp = vec[0] * rot_mat[1][0] + vec[1] * rot_mat[1][1] + vec[2] * rot_mat[1][2];

  3300.     const float z_tmp = vec[0] * rot_mat[2][0] + vec[1] * rot_mat[2][1] + vec[2] * rot_mat[2][2];

  3301. 

  3302.     vec[0] = x_tmp;

  3303.     vec[1] = y_tmp;

  3304.     vec[2] = z_tmp;

  3305. }

  3306. 

  3307. static inline void set_mirror_modifier(int h_flip, int v_flip, int d_flip,

  3308.                                        float *modifier)

  3309. {

  3310.     modifier[0] = h_flip ? -1.f : 1.f;

  3311.     modifier[1] = v_flip ? -1.f : 1.f;

  3312.     modifier[2] = d_flip ? -1.f : 1.f;

  3313. }

  3314. 

  3315. static inline void mirror(const float *modifier, float *vec)

  3316. {

  3317.     vec[0] *= modifier[0];

  3318.     vec[1] *= modifier[1];

  3319.     vec[2] *= modifier[2];

  3320. }

  3321. 

  3322. static int allocate_plane(V360Context *s, int sizeof_uv, int sizeof_ker, int sizeof_mask, int p)

  3323. {

  3324.     if (!s->u[p])

  3325.         s->u[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_uv);

  3326.     if (!s->v[p])

  3327.         s->v[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_uv);

  3328.     if (!s->u[p] || !s->v[p])

  3329.         return AVERROR(ENOMEM);

  3330.     if (sizeof_ker) {

  3331.         if (!s->ker[p])

  3332.             s->ker[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_ker);

  3333.         if (!s->ker[p])

  3334.             return AVERROR(ENOMEM);

  3335.     }

  3336. 

  3337.     if (sizeof_mask && !p) {

  3338.         if (!s->mask)

  3339.             s->mask = av_calloc(s->pr_width[p] * s->pr_height[p], sizeof_mask);

  3340.         if (!s->mask)

  3341.             return AVERROR(ENOMEM);

  3342.     }

  3343. 

  3344.     return 0;

  3345. }

  3346. 

  3347. static void fov_from_dfov(int format, float d_fov, float w, float h, float *h_fov, float *v_fov)

  3348. {

  3349.     switch (format) {

  3350.     case FISHEYE:

  3351.         {

  3352.             const float d = 0.5f * hypotf(w, h);

  3353. 

  3354.             *h_fov = d / h * d_fov;

  3355.             *v_fov = d / w * d_fov;

  3356.         }

  3357.         break;

  3358.     case FLAT:

  3359.     default:

  3360.         {

  3361.             const float da = tanf(0.5 * FFMIN(d_fov, 359.f) * M_PI / 180.f);

  3362.             const float d = hypotf(w, h);

  3363. 

  3364.             *h_fov = atan2f(da * w, d) * 360.f / M_PI;

  3365.             *v_fov = atan2f(da * h, d) * 360.f / M_PI;

  3366. 

  3367.             if (*h_fov < 0.f)

  3368.                 *h_fov += 360.f;

  3369.             if (*v_fov < 0.f)

  3370.                 *v_fov += 360.f;

  3371.         }

  3372.         break;

  3373.     }

  3374. }

  3375. 

  3376. static void set_dimensions(int *outw, int *outh, int w, int h, const AVPixFmtDescriptor *desc)

  3377. {

  3378.     outw[1] = outw[2] = FF_CEIL_RSHIFT(w, desc->log2_chroma_w);

  3379.     outw[0] = outw[3] = w;

  3380.     outh[1] = outh[2] = FF_CEIL_RSHIFT(h, desc->log2_chroma_h);

  3381.     outh[0] = outh[3] = h;

  3382. }

  3383. 

  3384. // Calculate remap data

  3385. static av_always_inline int v360_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)

  3386. {

  3387.     V360Context *s = ctx->priv;

  3388. 

  3389.     for (int p = 0; p < s->nb_allocated; p++) {

  3390.         const int max_value = s->max_value;

  3391.         const int width = s->pr_width[p];

  3392.         const int uv_linesize = s->uv_linesize[p];

  3393.         const int height = s->pr_height[p];

  3394.         const int in_width = s->inplanewidth[p];

  3395.         const int in_height = s->inplaneheight[p];

  3396.         const int slice_start = (height *  jobnr     ) / nb_jobs;

  3397.         const int slice_end   = (height * (jobnr + 1)) / nb_jobs;

  3398.         float du, dv;

  3399.         float vec[3];

  3400.         XYRemap rmap;

  3401. 

  3402.         for (int j = slice_start; j < slice_end; j++) {

  3403.             for (int i = 0; i < width; i++) {

  3404.                 int16_t *u = s->u[p] + (j * uv_linesize + i) * s->elements;

  3405.                 int16_t *v = s->v[p] + (j * uv_linesize + i) * s->elements;

  3406.                 int16_t *ker = s->ker[p] + (j * uv_linesize + i) * s->elements;

  3407.                 uint8_t *mask8 = p ? NULL : s->mask + (j * s->pr_width[0] + i);

  3408.                 uint16_t *mask16 = p ? NULL : (uint16_t *)s->mask + (j * s->pr_width[0] + i);

  3409.                 int in_mask, out_mask;

  3410. 

  3411.                 if (s->out_transpose)

  3412.                     out_mask = s->out_transform(s, j, i, height, width, vec);

  3413.                 else

  3414.                     out_mask = s->out_transform(s, i, j, width, height, vec);

  3415.                 av_assert1(!isnan(vec[0]) && !isnan(vec[1]) && !isnan(vec[2]));

  3416.                 rotate(s->rot_mat, vec);

  3417.                 av_assert1(!isnan(vec[0]) && !isnan(vec[1]) && !isnan(vec[2]));

  3418.                 normalize_vector(vec);

  3419.                 mirror(s->output_mirror_modifier, vec);

  3420.                 if (s->in_transpose)

  3421.                     in_mask = s->in_transform(s, vec, in_height, in_width, rmap.v, rmap.u, &du, &dv);

  3422.                 else

  3423.                     in_mask = s->in_transform(s, vec, in_width, in_height, rmap.u, rmap.v, &du, &dv);

  3424.                 av_assert1(!isnan(du) && !isnan(dv));

  3425.                 s->calculate_kernel(du, dv, &rmap, u, v, ker);

  3426. 

  3427.                 if (!p && s->mask) {

  3428.                     if (s->mask_size == 1) {

  3429.                         mask8[0] = 255 * (out_mask & in_mask);

  3430.                     } else {

  3431.                         mask16[0] = max_value * (out_mask & in_mask);

  3432.                     }

  3433.                 }

  3434.             }

  3435.         }

  3436.     }

  3437. 

  3438.     return 0;

  3439. }

  3440. 

  3441. static int config_output(AVFilterLink *outlink)

  3442. {

  3443.     AVFilterContext *ctx = outlink->src;

  3444.     AVFilterLink *inlink = ctx->inputs[0];

  3445.     V360Context *s = ctx->priv;

  3446.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);

  3447.     const int depth = desc->comp[0].depth;

  3448.     const int sizeof_mask = s->mask_size = (depth + 7) >> 3;

  3449.     int sizeof_uv;

  3450.     int sizeof_ker;

  3451.     int err;

  3452.     int h, w;

  3453.     int in_offset_h, in_offset_w;

  3454.     int out_offset_h, out_offset_w;

  3455.     float hf, wf;

  3456.     int (*prepare_out)(AVFilterContext *ctx);

  3457.     int have_alpha;

  3458. 

  3459.     s->max_value = (1 << depth) - 1;

  3460.     s->input_mirror_modifier[0] = s->ih_flip ? -1.f : 1.f;

  3461.     s->input_mirror_modifier[1] = s->iv_flip ? -1.f : 1.f;

  3462. 

  3463.     switch (s->interp) {

  3464.     case NEAREST:

  3465.         s->calculate_kernel = nearest_kernel;

  3466.         s->remap_slice = depth <= 8 ? remap1_8bit_slice : remap1_16bit_slice;

  3467.         s->elements = 1;

  3468.         sizeof_uv = sizeof(int16_t) * s->elements;

  3469.         sizeof_ker = 0;

  3470.         break;

  3471.     case BILINEAR:

  3472.         s->calculate_kernel = bilinear_kernel;

  3473.         s->remap_slice = depth <= 8 ? remap2_8bit_slice : remap2_16bit_slice;

  3474.         s->elements = 2 * 2;

  3475.         sizeof_uv = sizeof(int16_t) * s->elements;

  3476.         sizeof_ker = sizeof(int16_t) * s->elements;

  3477.         break;

  3478.     case BICUBIC:

  3479.         s->calculate_kernel = bicubic_kernel;

  3480.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3481.         s->elements = 4 * 4;

  3482.         sizeof_uv = sizeof(int16_t) * s->elements;

  3483.         sizeof_ker = sizeof(int16_t) * s->elements;

  3484.         break;

  3485.     case LANCZOS:

  3486.         s->calculate_kernel = lanczos_kernel;

  3487.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3488.         s->elements = 4 * 4;

  3489.         sizeof_uv = sizeof(int16_t) * s->elements;

  3490.         sizeof_ker = sizeof(int16_t) * s->elements;

  3491.         break;

  3492.     case SPLINE16:

  3493.         s->calculate_kernel = spline16_kernel;

  3494.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3495.         s->elements = 4 * 4;

  3496.         sizeof_uv = sizeof(int16_t) * s->elements;

  3497.         sizeof_ker = sizeof(int16_t) * s->elements;

  3498.         break;

  3499.     case GAUSSIAN:

  3500.         s->calculate_kernel = gaussian_kernel;

  3501.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3502.         s->elements = 4 * 4;

  3503.         sizeof_uv = sizeof(int16_t) * s->elements;

  3504.         sizeof_ker = sizeof(int16_t) * s->elements;

  3505.         break;

  3506.     default:

  3507.         av_assert0(0);

  3508.     }

  3509. 

  3510.     ff_v360_init(s, depth);

  3511. 

  3512.     for (int order = 0; order < NB_RORDERS; order++) {

  3513.         const char c = s->rorder[order];

  3514.         int rorder;

  3515. 

  3516.         if (c == '\0') {

  3517.             av_log(ctx, AV_LOG_WARNING,

  3518.                    "Incomplete rorder option. Direction for all 3 rotation orders should be specified. Switching to default rorder.\n");

  3519.             s->rotation_order[0] = YAW;

  3520.             s->rotation_order[1] = PITCH;

  3521.             s->rotation_order[2] = ROLL;

  3522.             break;

  3523.         }

  3524. 

  3525.         rorder = get_rorder(c);

  3526.         if (rorder == -1) {

  3527.             av_log(ctx, AV_LOG_WARNING,

  3528.                    "Incorrect rotation order symbol '%c' in rorder option. Switching to default rorder.\n", c);

  3529.             s->rotation_order[0] = YAW;

  3530.             s->rotation_order[1] = PITCH;

  3531.             s->rotation_order[2] = ROLL;

  3532.             break;

  3533.         }

  3534. 

  3535.         s->rotation_order[order] = rorder;

  3536.     }

  3537. 

  3538.     switch (s->in_stereo) {

  3539.     case STEREO_2D:

  3540.         w = inlink->w;

  3541.         h = inlink->h;

  3542.         in_offset_w = in_offset_h = 0;

  3543.         break;

  3544.     case STEREO_SBS:

  3545.         w = inlink->w / 2;

  3546.         h = inlink->h;

  3547.         in_offset_w = w;

  3548.         in_offset_h = 0;

  3549.         break;

  3550.     case STEREO_TB:

  3551.         w = inlink->w;

  3552.         h = inlink->h / 2;

  3553.         in_offset_w = 0;

  3554.         in_offset_h = h;

  3555.         break;

  3556.     default:

  3557.         av_assert0(0);

  3558.     }

  3559. 

  3560.     set_dimensions(s->inplanewidth, s->inplaneheight, w, h, desc);

  3561.     set_dimensions(s->in_offset_w, s->in_offset_h, in_offset_w, in_offset_h, desc);

  3562. 

  3563.     s->in_width = s->inplanewidth[0];

  3564.     s->in_height = s->inplaneheight[0];

  3565. 

  3566.     if (s->id_fov > 0.f)

  3567.         fov_from_dfov(s->in, s->id_fov, w, h, &s->ih_fov, &s->iv_fov);

  3568. 

  3569.     if (s->in_transpose)

  3570.         FFSWAP(int, s->in_width, s->in_height);

  3571. 

  3572.     switch (s->in) {

  3573.     case EQUIRECTANGULAR:

  3574.         s->in_transform = xyz_to_equirect;

  3575.         err = 0;

  3576.         wf = w;

  3577.         hf = h;

  3578.         break;

  3579.     case CUBEMAP_3_2:

  3580.         s->in_transform = xyz_to_cube3x2;

  3581.         err = prepare_cube_in(ctx);

  3582.         wf = w / 3.f * 4.f;

  3583.         hf = h;

  3584.         break;

  3585.     case CUBEMAP_1_6:

  3586.         s->in_transform = xyz_to_cube1x6;

  3587.         err = prepare_cube_in(ctx);

  3588.         wf = w * 4.f;

  3589.         hf = h / 3.f;

  3590.         break;

  3591.     case CUBEMAP_6_1:

  3592.         s->in_transform = xyz_to_cube6x1;

  3593.         err = prepare_cube_in(ctx);

  3594.         wf = w / 3.f * 2.f;

  3595.         hf = h * 2.f;

  3596.         break;

  3597.     case EQUIANGULAR:

  3598.         s->in_transform = xyz_to_eac;

  3599.         err = prepare_eac_in(ctx);

  3600.         wf = w;

  3601.         hf = h / 9.f * 8.f;

  3602.         break;

  3603.     case FLAT:

  3604.         s->in_transform = xyz_to_flat;

  3605.         err = prepare_flat_in(ctx);

  3606.         wf = w;

  3607.         hf = h;

  3608.         break;

  3609.     case PERSPECTIVE:

  3610.     case PANNINI:

  3611.         av_log(ctx, AV_LOG_ERROR, "Supplied format is not accepted as input.\n");

  3612.         return AVERROR(EINVAL);

  3613.     case DUAL_FISHEYE:

  3614.         s->in_transform = xyz_to_dfisheye;

  3615.         err = 0;

  3616.         wf = w;

  3617.         hf = h;

  3618.         break;

  3619.     case BARREL:

  3620.         s->in_transform = xyz_to_barrel;

  3621.         err = 0;

  3622.         wf = w / 5.f * 4.f;

  3623.         hf = h;

  3624.         break;

  3625.     case STEREOGRAPHIC:

  3626.         s->in_transform = xyz_to_stereographic;

  3627.         err = prepare_stereographic_in(ctx);

  3628.         wf = w;

  3629.         hf = h / 2.f;

  3630.         break;

  3631.     case MERCATOR:

  3632.         s->in_transform = xyz_to_mercator;

  3633.         err = 0;

  3634.         wf = w;

  3635.         hf = h / 2.f;

  3636.         break;

  3637.     case BALL:

  3638.         s->in_transform = xyz_to_ball;

  3639.         err = 0;

  3640.         wf = w;

  3641.         hf = h / 2.f;

  3642.         break;

  3643.     case HAMMER:

  3644.         s->in_transform = xyz_to_hammer;

  3645.         err = 0;

  3646.         wf = w;

  3647.         hf = h;

  3648.         break;

  3649.     case SINUSOIDAL:

  3650.         s->in_transform = xyz_to_sinusoidal;

  3651.         err = 0;

  3652.         wf = w;

  3653.         hf = h;

  3654.         break;

  3655.     case FISHEYE:

  3656.         s->in_transform = xyz_to_fisheye;

  3657.         err = prepare_fisheye_in(ctx);

  3658.         wf = w * 2;

  3659.         hf = h;

  3660.         break;

  3661.     case CYLINDRICAL:

  3662.         s->in_transform = xyz_to_cylindrical;

  3663.         err = prepare_cylindrical_in(ctx);

  3664.         wf = w;

  3665.         hf = h * 2.f;

  3666.         break;

  3667.     case TETRAHEDRON:

  3668.         s->in_transform = xyz_to_tetrahedron;

  3669.         err = 0;

  3670.         wf = w;

  3671.         hf = h;

  3672.         break;

  3673.     case BARREL_SPLIT:

  3674.         s->in_transform = xyz_to_barrelsplit;

  3675.         err = 0;

  3676.         wf = w * 4.f / 3.f;

  3677.         hf = h;

  3678.         break;

  3679.     default:

  3680.         av_log(ctx, AV_LOG_ERROR, "Specified input format is not handled.\n");

  3681.         return AVERROR_BUG;

  3682.     }

  3683. 

  3684.     if (err != 0) {

  3685.         return err;

  3686.     }

  3687. 

  3688.     switch (s->out) {

  3689.     case EQUIRECTANGULAR:

  3690.         s->out_transform = equirect_to_xyz;

  3691.         prepare_out = NULL;

  3692.         w = lrintf(wf);

  3693.         h = lrintf(hf);

  3694.         break;

  3695.     case CUBEMAP_3_2:

  3696.         s->out_transform = cube3x2_to_xyz;

  3697.         prepare_out = prepare_cube_out;

  3698.         w = lrintf(wf / 4.f * 3.f);

  3699.         h = lrintf(hf);

  3700.         break;

  3701.     case CUBEMAP_1_6:

  3702.         s->out_transform = cube1x6_to_xyz;

  3703.         prepare_out = prepare_cube_out;

  3704.         w = lrintf(wf / 4.f);

  3705.         h = lrintf(hf * 3.f);

  3706.         break;

  3707.     case CUBEMAP_6_1:

  3708.         s->out_transform = cube6x1_to_xyz;

  3709.         prepare_out = prepare_cube_out;

  3710.         w = lrintf(wf / 2.f * 3.f);

  3711.         h = lrintf(hf / 2.f);

  3712.         break;

  3713.     case EQUIANGULAR:

  3714.         s->out_transform = eac_to_xyz;

  3715.         prepare_out = prepare_eac_out;

  3716.         w = lrintf(wf);

  3717.         h = lrintf(hf / 8.f * 9.f);

  3718.         break;

  3719.     case FLAT:

  3720.         s->out_transform = flat_to_xyz;

  3721.         prepare_out = prepare_flat_out;

  3722.         w = lrintf(wf);

  3723.         h = lrintf(hf);

  3724.         break;

  3725.     case DUAL_FISHEYE:

  3726.         s->out_transform = dfisheye_to_xyz;

  3727.         prepare_out = NULL;

  3728.         w = lrintf(wf);

  3729.         h = lrintf(hf);

  3730.         break;

  3731.     case BARREL:

  3732.         s->out_transform = barrel_to_xyz;

  3733.         prepare_out = NULL;

  3734.         w = lrintf(wf / 4.f * 5.f);

  3735.         h = lrintf(hf);

  3736.         break;

  3737.     case STEREOGRAPHIC:

  3738.         s->out_transform = stereographic_to_xyz;

  3739.         prepare_out = prepare_stereographic_out;

  3740.         w = lrintf(wf);

  3741.         h = lrintf(hf * 2.f);

  3742.         break;

  3743.     case MERCATOR:

  3744.         s->out_transform = mercator_to_xyz;

  3745.         prepare_out = NULL;

  3746.         w = lrintf(wf);

  3747.         h = lrintf(hf * 2.f);

  3748.         break;

  3749.     case BALL:

  3750.         s->out_transform = ball_to_xyz;

  3751.         prepare_out = NULL;

  3752.         w = lrintf(wf);

  3753.         h = lrintf(hf * 2.f);

  3754.         break;

  3755.     case HAMMER:

  3756.         s->out_transform = hammer_to_xyz;

  3757.         prepare_out = NULL;

  3758.         w = lrintf(wf);

  3759.         h = lrintf(hf);

  3760.         break;

  3761.     case SINUSOIDAL:

  3762.         s->out_transform = sinusoidal_to_xyz;

  3763.         prepare_out = NULL;

  3764.         w = lrintf(wf);

  3765.         h = lrintf(hf);

  3766.         break;

  3767.     case FISHEYE:

  3768.         s->out_transform = fisheye_to_xyz;

  3769.         prepare_out = prepare_fisheye_out;

  3770.         w = lrintf(wf * 0.5f);

  3771.         h = lrintf(hf);

  3772.         break;

  3773.     case PANNINI:

  3774.         s->out_transform = pannini_to_xyz;

  3775.         prepare_out = NULL;

  3776.         w = lrintf(wf);

  3777.         h = lrintf(hf);

  3778.         break;

  3779.     case CYLINDRICAL:

  3780.         s->out_transform = cylindrical_to_xyz;

  3781.         prepare_out = prepare_cylindrical_out;

  3782.         w = lrintf(wf);

  3783.         h = lrintf(hf * 0.5f);

  3784.         break;

  3785.     case PERSPECTIVE:

  3786.         s->out_transform = perspective_to_xyz;

  3787.         prepare_out = NULL;

  3788.         w = lrintf(wf / 2.f);

  3789.         h = lrintf(hf);

  3790.         break;

  3791.     case TETRAHEDRON:

  3792.         s->out_transform = tetrahedron_to_xyz;

  3793.         prepare_out = NULL;

  3794.         w = lrintf(wf);

  3795.         h = lrintf(hf);

  3796.         break;

  3797.     case BARREL_SPLIT:

  3798.         s->out_transform = barrelsplit_to_xyz;

  3799.         prepare_out = NULL;

  3800.         w = lrintf(wf / 4.f * 3.f);

  3801.         h = lrintf(hf);

  3802.         break;

  3803.     default:

  3804.         av_log(ctx, AV_LOG_ERROR, "Specified output format is not handled.\n");

  3805.         return AVERROR_BUG;

  3806.     }

  3807. 

  3808.     // Override resolution with user values if specified

  3809.     if (s->width > 0 && s->height <= 0 && s->h_fov > 0.f && s->v_fov > 0.f &&

  3810.         s->out == FLAT && s->d_fov == 0.f) {

  3811.         w = s->width;

  3812.         h = w / tanf(s->h_fov * M_PI / 360.f) * tanf(s->v_fov * M_PI / 360.f);

  3813.     } else if (s->width <= 0 && s->height > 0 && s->h_fov > 0.f && s->v_fov > 0.f &&

  3814.         s->out == FLAT && s->d_fov == 0.f) {

  3815.         h = s->height;

  3816.         w = h / tanf(s->v_fov * M_PI / 360.f) * tanf(s->h_fov * M_PI / 360.f);

  3817.     } else if (s->width > 0 && s->height > 0) {

  3818.         w = s->width;

  3819.         h = s->height;

  3820.     } else if (s->width > 0 || s->height > 0) {

  3821.         av_log(ctx, AV_LOG_ERROR, "Both width and height values should be specified.\n");

  3822.         return AVERROR(EINVAL);

  3823.     } else {

  3824.         if (s->out_transpose)

  3825.             FFSWAP(int, w, h);

  3826. 

  3827.         if (s->in_transpose)

  3828.             FFSWAP(int, w, h);

  3829.     }

  3830. 

  3831.     s->width  = w;

  3832.     s->height = h;

  3833. 

  3834.     if (s->d_fov > 0.f)

  3835.         fov_from_dfov(s->out, s->d_fov, w, h, &s->h_fov, &s->v_fov);

  3836. 

  3837.     if (prepare_out) {

  3838.         err = prepare_out(ctx);

  3839.         if (err != 0)

  3840.             return err;

  3841.     }

  3842. 

  3843.     set_dimensions(s->pr_width, s->pr_height, w, h, desc);

  3844. 

  3845.     s->out_width = s->pr_width[0];

  3846.     s->out_height = s->pr_height[0];

  3847. 

  3848.     if (s->out_transpose)

  3849.         FFSWAP(int, s->out_width, s->out_height);

  3850. 

  3851.     switch (s->out_stereo) {

  3852.     case STEREO_2D:

  3853.         out_offset_w = out_offset_h = 0;

  3854.         break;

  3855.     case STEREO_SBS:

  3856.         out_offset_w = w;

  3857.         out_offset_h = 0;

  3858.         w *= 2;

  3859.         break;

  3860.     case STEREO_TB:

  3861.         out_offset_w = 0;

  3862.         out_offset_h = h;

  3863.         h *= 2;

  3864.         break;

  3865.     default:

  3866.         av_assert0(0);

  3867.     }

  3868. 

  3869.     set_dimensions(s->out_offset_w, s->out_offset_h, out_offset_w, out_offset_h, desc);

  3870.     set_dimensions(s->planewidth, s->planeheight, w, h, desc);

  3871. 

  3872.     for (int i = 0; i < 4; i++)

  3873.         s->uv_linesize[i] = FFALIGN(s->pr_width[i], 8);

  3874. 

  3875.     outlink->h = h;

  3876.     outlink->w = w;

  3877. 

  3878.     s->nb_planes = av_pix_fmt_count_planes(inlink->format);

  3879.     have_alpha   = !!(desc->flags & AV_PIX_FMT_FLAG_ALPHA);

  3880. 

  3881.     if (desc->log2_chroma_h == desc->log2_chroma_w && desc->log2_chroma_h == 0) {

  3882.         s->nb_allocated = 1;

  3883.         s->map[0] = s->map[1] = s->map[2] = s->map[3] = 0;

  3884.     } else {

  3885.         s->nb_allocated = 2;

  3886.         s->map[0] = s->map[3] = 0;

  3887.         s->map[1] = s->map[2] = 1;

  3888.     }

  3889. 

  3890.     for (int i = 0; i < s->nb_allocated; i++)

  3891.         allocate_plane(s, sizeof_uv, sizeof_ker, sizeof_mask * have_alpha * s->alpha, i);

  3892. 

  3893.     calculate_rotation_matrix(s->yaw, s->pitch, s->roll, s->rot_mat, s->rotation_order);

  3894.     set_mirror_modifier(s->h_flip, s->v_flip, s->d_flip, s->output_mirror_modifier);

  3895. 

  3896.     ctx->internal->execute(ctx, v360_slice, NULL, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));

  3897. 

  3898.     return 0;

  3899. }

  3900. 

  3901. static int filter_frame(AVFilterLink *inlink, AVFrame *in)

  3902. {

  3903.     AVFilterContext *ctx = inlink->dst;

  3904.     AVFilterLink *outlink = ctx->outputs[0];

  3905.     V360Context *s = ctx->priv;

  3906.     AVFrame *out;

  3907.     ThreadData td;

  3908. 

  3909.     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);

  3910.     if (!out) {

  3911.         av_frame_free(&in);

  3912.         return AVERROR(ENOMEM);

  3913.     }

  3914.     av_frame_copy_props(out, in);

  3915. 

  3916.     td.in = in;

  3917.     td.out = out;

  3918. 

  3919.     ctx->internal->execute(ctx, s->remap_slice, &td, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));

  3920. 

  3921.     av_frame_free(&in);

  3922.     return ff_filter_frame(outlink, out);

  3923. }

  3924. 

  3925. static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,

  3926.                            char *res, int res_len, int flags)

  3927. {

  3928.     int ret;

  3929. 

  3930.     ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);

  3931.     if (ret < 0)

  3932.         return ret;

  3933. 

  3934.     return config_output(ctx->outputs[0]);

  3935. }

  3936. 

  3937. static av_cold void uninit(AVFilterContext *ctx)

  3938. {

  3939.     V360Context *s = ctx->priv;

  3940. 

  3941.     for (int p = 0; p < s->nb_allocated; p++) {

  3942.         av_freep(&s->u[p]);

  3943.         av_freep(&s->v[p]);

  3944.         av_freep(&s->ker[p]);

  3945.     }

  3946.     av_freep(&s->mask);

  3947. }

  3948. 

  3949. static const AVFilterPad inputs[] = {

  3950.     {

  3951.         .name         = "default",

  3952.         .type         = AVMEDIA_TYPE_VIDEO,

  3953.         .filter_frame = filter_frame,

  3954.     },

  3955.     { NULL }

  3956. };

  3957. 

  3958. static const AVFilterPad outputs[] = {

  3959.     {

  3960.         .name         = "default",

  3961.         .type         = AVMEDIA_TYPE_VIDEO,

  3962.         .config_props = config_output,

  3963.     },

  3964.     { NULL }

  3965. };

  3966. 

  3967. AVFilter ff_vf_v360 = {

  3968.     .name          = "v360",

  3969.     .description   = NULL_IF_CONFIG_SMALL("Convert 360 projection of video."),

  3970.     .priv_size     = sizeof(V360Context),

  3971.     .uninit        = uninit,

  3972.     .query_formats = query_formats,

  3973.     .inputs        = inputs,

  3974.     .outputs       = outputs,

  3975.     .priv_class    = &v360_class,

  3976.     .flags         = AVFILTER_FLAG_SLICE_THREADS,

  3977.     .process_command = process_command,

  3978. };