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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.  * Convert char to corresponding direction.

  627.  * Used for cubemap options.

  628.  */

  629. static int get_direction(char c)

  630. {

  631.     switch (c) {

  632.     case 'r':

  633.         return RIGHT;

  634.     case 'l':

  635.         return LEFT;

  636.     case 'u':

  637.         return UP;

  638.     case 'd':

  639.         return DOWN;

  640.     case 'f':

  641.         return FRONT;

  642.     case 'b':

  643.         return BACK;

  644.     default:

  645.         return -1;

  646.     }

  647. }

  648. 

  649. /**

  650.  * Convert char to corresponding rotation angle.

  651.  * Used for cubemap options.

  652.  */

  653. static int get_rotation(char c)

  654. {

  655.     switch (c) {

  656.     case '0':

  657.         return ROT_0;

  658.     case '1':

  659.         return ROT_90;

  660.     case '2':

  661.         return ROT_180;

  662.     case '3':

  663.         return ROT_270;

  664.     default:

  665.         return -1;

  666.     }

  667. }

  668. 

  669. /**

  670.  * Convert char to corresponding rotation order.

  671.  */

  672. static int get_rorder(char c)

  673. {

  674.     switch (c) {

  675.     case 'Y':

  676.     case 'y':

  677.         return YAW;

  678.     case 'P':

  679.     case 'p':

  680.         return PITCH;

  681.     case 'R':

  682.     case 'r':

  683.         return ROLL;

  684.     default:

  685.         return -1;

  686.     }

  687. }

  688. 

  689. /**

  690.  * Prepare data for processing cubemap input format.

  691.  *

  692.  * @param ctx filter context

  693.  *

  694.  * @return error code

  695.  */

  696. static int prepare_cube_in(AVFilterContext *ctx)

  697. {

  698.     V360Context *s = ctx->priv;

  699. 

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

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

  702.         int direction;

  703. 

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

  705.             av_log(ctx, AV_LOG_ERROR,

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

  707.             return AVERROR(EINVAL);

  708.         }

  709. 

  710.         direction = get_direction(c);

  711.         if (direction == -1) {

  712.             av_log(ctx, AV_LOG_ERROR,

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

  714.             return AVERROR(EINVAL);

  715.         }

  716. 

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

  718.     }

  719. 

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

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

  722.         int rotation;

  723. 

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

  725.             av_log(ctx, AV_LOG_ERROR,

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

  727.             return AVERROR(EINVAL);

  728.         }

  729. 

  730.         rotation = get_rotation(c);

  731.         if (rotation == -1) {

  732.             av_log(ctx, AV_LOG_ERROR,

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

  734.             return AVERROR(EINVAL);

  735.         }

  736. 

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

  738.     }

  739. 

  740.     return 0;

  741. }

  742. 

  743. /**

  744.  * Prepare data for processing cubemap output format.

  745.  *

  746.  * @param ctx filter context

  747.  *

  748.  * @return error code

  749.  */

  750. static int prepare_cube_out(AVFilterContext *ctx)

  751. {

  752.     V360Context *s = ctx->priv;

  753. 

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

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

  756.         int direction;

  757. 

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

  759.             av_log(ctx, AV_LOG_ERROR,

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

  761.             return AVERROR(EINVAL);

  762.         }

  763. 

  764.         direction = get_direction(c);

  765.         if (direction == -1) {

  766.             av_log(ctx, AV_LOG_ERROR,

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

  768.             return AVERROR(EINVAL);

  769.         }

  770. 

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

  772.     }

  773. 

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

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

  776.         int rotation;

  777. 

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

  779.             av_log(ctx, AV_LOG_ERROR,

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

  781.             return AVERROR(EINVAL);

  782.         }

  783. 

  784.         rotation = get_rotation(c);

  785.         if (rotation == -1) {

  786.             av_log(ctx, AV_LOG_ERROR,

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

  788.             return AVERROR(EINVAL);

  789.         }

  790. 

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

  792.     }

  793. 

  794.     return 0;

  795. }

  796. 

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

  798. {

  799.     float tmp;

  800. 

  801.     switch (rotation) {

  802.     case ROT_0:

  803.         break;

  804.     case ROT_90:

  805.         tmp =  *uf;

  806.         *uf = -*vf;

  807.         *vf =  tmp;

  808.         break;

  809.     case ROT_180:

  810.         *uf = -*uf;

  811.         *vf = -*vf;

  812.         break;

  813.     case ROT_270:

  814.         tmp = -*uf;

  815.         *uf =  *vf;

  816.         *vf =  tmp;

  817.         break;

  818.     default:

  819.         av_assert0(0);

  820.     }

  821. }

  822. 

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

  824. {

  825.     float tmp;

  826. 

  827.     switch (rotation) {

  828.     case ROT_0:

  829.         break;

  830.     case ROT_90:

  831.         tmp = -*uf;

  832.         *uf =  *vf;

  833.         *vf =  tmp;

  834.         break;

  835.     case ROT_180:

  836.         *uf = -*uf;

  837.         *vf = -*vf;

  838.         break;

  839.     case ROT_270:

  840.         tmp =  *uf;

  841.         *uf = -*vf;

  842.         *vf =  tmp;

  843.         break;

  844.     default:

  845.         av_assert0(0);

  846.     }

  847. }

  848. 

  849. /**

  850.  * Normalize vector.

  851.  *

  852.  * @param vec vector

  853.  */

  854. static void normalize_vector(float *vec)

  855. {

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

  857. 

  858.     vec[0] /= norm;

  859.     vec[1] /= norm;

  860.     vec[2] /= norm;

  861. }

  862. 

  863. /**

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

  865.  * Common operation for every cubemap.

  866.  *

  867.  * @param s filter private context

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

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

  870.  * @param face face of cubemap

  871.  * @param vec coordinates on sphere

  872.  * @param scalew scale for uf

  873.  * @param scaleh scale for vf

  874.  */

  875. static void cube_to_xyz(const V360Context *s,

  876.                         float uf, float vf, int face,

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

  878. {

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

  880.     float l_x, l_y, l_z;

  881. 

  882.     uf /= scalew;

  883.     vf /= scaleh;

  884. 

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

  886. 

  887.     switch (direction) {

  888.     case RIGHT:

  889.         l_x =  1.f;

  890.         l_y = -vf;

  891.         l_z =  uf;

  892.         break;

  893.     case LEFT:

  894.         l_x = -1.f;

  895.         l_y = -vf;

  896.         l_z = -uf;

  897.         break;

  898.     case UP:

  899.         l_x =  uf;

  900.         l_y =  1.f;

  901.         l_z = -vf;

  902.         break;

  903.     case DOWN:

  904.         l_x =  uf;

  905.         l_y = -1.f;

  906.         l_z =  vf;

  907.         break;

  908.     case FRONT:

  909.         l_x =  uf;

  910.         l_y = -vf;

  911.         l_z = -1.f;

  912.         break;

  913.     case BACK:

  914.         l_x = -uf;

  915.         l_y = -vf;

  916.         l_z =  1.f;

  917.         break;

  918.     default:

  919.         av_assert0(0);

  920.     }

  921. 

  922.     vec[0] = l_x;

  923.     vec[1] = l_y;

  924.     vec[2] = l_z;

  925. 

  926.     normalize_vector(vec);

  927. }

  928. 

  929. /**

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

  931.  * Common operation for every cubemap.

  932.  *

  933.  * @param s filter private context

  934.  * @param vec coordinated on sphere

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

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

  937.  * @param direction direction of view

  938.  */

  939. static void xyz_to_cube(const V360Context *s,

  940.                         const float *vec,

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

  942. {

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

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

  945.     float phi_norm, theta_threshold;

  946.     int face;

  947. 

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

  949.         *direction = FRONT;

  950.         phi_norm = phi;

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

  952.         *direction = LEFT;

  953.         phi_norm = phi + M_PI_2;

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

  955.         *direction = RIGHT;

  956.         phi_norm = phi - M_PI_2;

  957.     } else {

  958.         *direction = BACK;

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

  960.     }

  961. 

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

  963.     if (theta > theta_threshold) {

  964.         *direction = DOWN;

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

  966.         *direction = UP;

  967.     }

  968. 

  969.     switch (*direction) {

  970.     case RIGHT:

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

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

  973.         break;

  974.     case LEFT:

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

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

  977.         break;

  978.     case UP:

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

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

  981.         break;

  982.     case DOWN:

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

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

  985.         break;

  986.     case FRONT:

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

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

  989.         break;

  990.     case BACK:

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

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

  993.         break;

  994.     default:

  995.         av_assert0(0);

  996.     }

  997. 

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

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

  1000. 

  1001.     (*uf) *= s->input_mirror_modifier[0];

  1002.     (*vf) *= s->input_mirror_modifier[1];

  1003. }

  1004. 

  1005. /**

  1006.  * Find position on another cube face in case of overflow/underflow.

  1007.  * Used for calculation of interpolation window.

  1008.  *

  1009.  * @param s filter private context

  1010.  * @param uf horizontal cubemap coordinate

  1011.  * @param vf vertical cubemap coordinate

  1012.  * @param direction direction of view

  1013.  * @param new_uf new horizontal cubemap coordinate

  1014.  * @param new_vf new vertical cubemap coordinate

  1015.  * @param face face position on cubemap

  1016.  */

  1017. static void process_cube_coordinates(const V360Context *s,

  1018.                                      float uf, float vf, int direction,

  1019.                                      float *new_uf, float *new_vf, int *face)

  1020. {

  1021.     /*

  1022.      *  Cubemap orientation

  1023.      *

  1024.      *           width

  1025.      *         <------->

  1026.      *         +-------+

  1027.      *         |       |                              U

  1028.      *         | up    |                   h       ------->

  1029.      * +-------+-------+-------+-------+ ^ e      |

  1030.      * |       |       |       |       | | i    V |

  1031.      * | left  | front | right | back  | | g      |

  1032.      * +-------+-------+-------+-------+ v h      v

  1033.      *         |       |                   t

  1034.      *         | down  |

  1035.      *         +-------+

  1036.      */

  1037. 

  1038.     *face = s->in_cubemap_face_order[direction];

  1039.     rotate_cube_face_inverse(&uf, &vf, s->in_cubemap_face_rotation[*face]);

  1040. 

  1041.     if ((uf < -1.f || uf >= 1.f) && (vf < -1.f || vf >= 1.f)) {

  1042.         // There are no pixels to use in this case

  1043.         *new_uf = uf;

  1044.         *new_vf = vf;

  1045.     } else if (uf < -1.f) {

  1046.         uf += 2.f;

  1047.         switch (direction) {

  1048.         case RIGHT:

  1049.             direction = FRONT;

  1050.             *new_uf =  uf;

  1051.             *new_vf =  vf;

  1052.             break;

  1053.         case LEFT:

  1054.             direction = BACK;

  1055.             *new_uf =  uf;

  1056.             *new_vf =  vf;

  1057.             break;

  1058.         case UP:

  1059.             direction = LEFT;

  1060.             *new_uf =  vf;

  1061.             *new_vf = -uf;

  1062.             break;

  1063.         case DOWN:

  1064.             direction = LEFT;

  1065.             *new_uf = -vf;

  1066.             *new_vf =  uf;

  1067.             break;

  1068.         case FRONT:

  1069.             direction = LEFT;

  1070.             *new_uf =  uf;

  1071.             *new_vf =  vf;

  1072.             break;

  1073.         case BACK:

  1074.             direction = RIGHT;

  1075.             *new_uf =  uf;

  1076.             *new_vf =  vf;

  1077.             break;

  1078.         default:

  1079.             av_assert0(0);

  1080.         }

  1081.     } else if (uf >= 1.f) {

  1082.         uf -= 2.f;

  1083.         switch (direction) {

  1084.         case RIGHT:

  1085.             direction = BACK;

  1086.             *new_uf =  uf;

  1087.             *new_vf =  vf;

  1088.             break;

  1089.         case LEFT:

  1090.             direction = FRONT;

  1091.             *new_uf =  uf;

  1092.             *new_vf =  vf;

  1093.             break;

  1094.         case UP:

  1095.             direction = RIGHT;

  1096.             *new_uf = -vf;

  1097.             *new_vf =  uf;

  1098.             break;

  1099.         case DOWN:

  1100.             direction = RIGHT;

  1101.             *new_uf =  vf;

  1102.             *new_vf = -uf;

  1103.             break;

  1104.         case FRONT:

  1105.             direction = RIGHT;

  1106.             *new_uf =  uf;

  1107.             *new_vf =  vf;

  1108.             break;

  1109.         case BACK:

  1110.             direction = LEFT;

  1111.             *new_uf =  uf;

  1112.             *new_vf =  vf;

  1113.             break;

  1114.         default:

  1115.             av_assert0(0);

  1116.         }

  1117.     } else if (vf < -1.f) {

  1118.         vf += 2.f;

  1119.         switch (direction) {

  1120.         case RIGHT:

  1121.             direction = UP;

  1122.             *new_uf =  vf;

  1123.             *new_vf = -uf;

  1124.             break;

  1125.         case LEFT:

  1126.             direction = UP;

  1127.             *new_uf = -vf;

  1128.             *new_vf =  uf;

  1129.             break;

  1130.         case UP:

  1131.             direction = BACK;

  1132.             *new_uf = -uf;

  1133.             *new_vf = -vf;

  1134.             break;

  1135.         case DOWN:

  1136.             direction = FRONT;

  1137.             *new_uf =  uf;

  1138.             *new_vf =  vf;

  1139.             break;

  1140.         case FRONT:

  1141.             direction = UP;

  1142.             *new_uf =  uf;

  1143.             *new_vf =  vf;

  1144.             break;

  1145.         case BACK:

  1146.             direction = UP;

  1147.             *new_uf = -uf;

  1148.             *new_vf = -vf;

  1149.             break;

  1150.         default:

  1151.             av_assert0(0);

  1152.         }

  1153.     } else if (vf >= 1.f) {

  1154.         vf -= 2.f;

  1155.         switch (direction) {

  1156.         case RIGHT:

  1157.             direction = DOWN;

  1158.             *new_uf = -vf;

  1159.             *new_vf =  uf;

  1160.             break;

  1161.         case LEFT:

  1162.             direction = DOWN;

  1163.             *new_uf =  vf;

  1164.             *new_vf = -uf;

  1165.             break;

  1166.         case UP:

  1167.             direction = FRONT;

  1168.             *new_uf =  uf;

  1169.             *new_vf =  vf;

  1170.             break;

  1171.         case DOWN:

  1172.             direction = BACK;

  1173.             *new_uf = -uf;

  1174.             *new_vf = -vf;

  1175.             break;

  1176.         case FRONT:

  1177.             direction = DOWN;

  1178.             *new_uf =  uf;

  1179.             *new_vf =  vf;

  1180.             break;

  1181.         case BACK:

  1182.             direction = DOWN;

  1183.             *new_uf = -uf;

  1184.             *new_vf = -vf;

  1185.             break;

  1186.         default:

  1187.             av_assert0(0);

  1188.         }

  1189.     } else {

  1190.         // Inside cube face

  1191.         *new_uf = uf;

  1192.         *new_vf = vf;

  1193.     }

  1194. 

  1195.     *face = s->in_cubemap_face_order[direction];

  1196.     rotate_cube_face(new_uf, new_vf, s->in_cubemap_face_rotation[*face]);

  1197. }

  1198. 

  1199. /**

  1200.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap3x2 format.

  1201.  *

  1202.  * @param s filter private context

  1203.  * @param i horizontal position on frame [0, width)

  1204.  * @param j vertical position on frame [0, height)

  1205.  * @param width frame width

  1206.  * @param height frame height

  1207.  * @param vec coordinates on sphere

  1208.  */

  1209. static int cube3x2_to_xyz(const V360Context *s,

  1210.                           int i, int j, int width, int height,

  1211.                           float *vec)

  1212. {

  1213.     const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_width  / 3.f) : 1.f - s->out_pad;

  1214.     const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_height / 2.f) : 1.f - s->out_pad;

  1215. 

  1216.     const float ew = width  / 3.f;

  1217.     const float eh = height / 2.f;

  1218. 

  1219.     const int u_face = floorf(i / ew);

  1220.     const int v_face = floorf(j / eh);

  1221.     const int face = u_face + 3 * v_face;

  1222. 

  1223.     const int u_shift = ceilf(ew * u_face);

  1224.     const int v_shift = ceilf(eh * v_face);

  1225.     const int ewi = ceilf(ew * (u_face + 1)) - u_shift;

  1226.     const int ehi = ceilf(eh * (v_face + 1)) - v_shift;

  1227. 

  1228.     const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;

  1229.     const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;

  1230. 

  1231.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1232. 

  1233.     return 1;

  1234. }

  1235. 

  1236. /**

  1237.  * Calculate frame position in cubemap3x2 format for corresponding 3D coordinates on sphere.

  1238.  *

  1239.  * @param s filter private context

  1240.  * @param vec coordinates on sphere

  1241.  * @param width frame width

  1242.  * @param height frame height

  1243.  * @param us horizontal coordinates for interpolation window

  1244.  * @param vs vertical coordinates for interpolation window

  1245.  * @param du horizontal relative coordinate

  1246.  * @param dv vertical relative coordinate

  1247.  */

  1248. static int xyz_to_cube3x2(const V360Context *s,

  1249.                           const float *vec, int width, int height,

  1250.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1251. {

  1252.     const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_width  / 3.f) : 1.f - s->in_pad;

  1253.     const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_height / 2.f) : 1.f - s->in_pad;

  1254.     const float ew = width  / 3.f;

  1255.     const float eh = height / 2.f;

  1256.     float uf, vf;

  1257.     int ui, vi;

  1258.     int ewi, ehi;

  1259.     int direction, face;

  1260.     int u_face, v_face;

  1261. 

  1262.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1263. 

  1264.     uf *= scalew;

  1265.     vf *= scaleh;

  1266. 

  1267.     face = s->in_cubemap_face_order[direction];

  1268.     u_face = face % 3;

  1269.     v_face = face / 3;

  1270.     ewi = ceilf(ew * (u_face + 1)) - ceilf(ew * u_face);

  1271.     ehi = ceilf(eh * (v_face + 1)) - ceilf(eh * v_face);

  1272. 

  1273.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1274.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1275. 

  1276.     ui = floorf(uf);

  1277.     vi = floorf(vf);

  1278. 

  1279.     *du = uf - ui;

  1280.     *dv = vf - vi;

  1281. 

  1282.     for (int i = 0; i < 4; i++) {

  1283.         for (int j = 0; j < 4; j++) {

  1284.             int new_ui = ui + j - 1;

  1285.             int new_vi = vi + i - 1;

  1286.             int u_shift, v_shift;

  1287.             int new_ewi, new_ehi;

  1288. 

  1289.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1290.                 face = s->in_cubemap_face_order[direction];

  1291. 

  1292.                 u_face = face % 3;

  1293.                 v_face = face / 3;

  1294.                 u_shift = ceilf(ew * u_face);

  1295.                 v_shift = ceilf(eh * v_face);

  1296.             } else {

  1297.                 uf = 2.f * new_ui / ewi - 1.f;

  1298.                 vf = 2.f * new_vi / ehi - 1.f;

  1299. 

  1300.                 uf /= scalew;

  1301.                 vf /= scaleh;

  1302. 

  1303.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1304. 

  1305.                 uf *= scalew;

  1306.                 vf *= scaleh;

  1307. 

  1308.                 u_face = face % 3;

  1309.                 v_face = face / 3;

  1310.                 u_shift = ceilf(ew * u_face);

  1311.                 v_shift = ceilf(eh * v_face);

  1312.                 new_ewi = ceilf(ew * (u_face + 1)) - u_shift;

  1313.                 new_ehi = ceilf(eh * (v_face + 1)) - v_shift;

  1314. 

  1315.                 new_ui = av_clip(lrintf(0.5f * new_ewi * (uf + 1.f)), 0, new_ewi - 1);

  1316.                 new_vi = av_clip(lrintf(0.5f * new_ehi * (vf + 1.f)), 0, new_ehi - 1);

  1317.             }

  1318. 

  1319.             us[i][j] = u_shift + new_ui;

  1320.             vs[i][j] = v_shift + new_vi;

  1321.         }

  1322.     }

  1323. 

  1324.     return 1;

  1325. }

  1326. 

  1327. /**

  1328.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap1x6 format.

  1329.  *

  1330.  * @param s filter private context

  1331.  * @param i horizontal position on frame [0, width)

  1332.  * @param j vertical position on frame [0, height)

  1333.  * @param width frame width

  1334.  * @param height frame height

  1335.  * @param vec coordinates on sphere

  1336.  */

  1337. static int cube1x6_to_xyz(const V360Context *s,

  1338.                           int i, int j, int width, int height,

  1339.                           float *vec)

  1340. {

  1341.     const float scalew = s->fout_pad > 0 ? 1.f - (float)(s->fout_pad) / s->out_width : 1.f - s->out_pad;

  1342.     const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_height / 6.f) : 1.f - s->out_pad;

  1343. 

  1344.     const float ew = width;

  1345.     const float eh = height / 6.f;

  1346. 

  1347.     const int face = floorf(j / eh);

  1348. 

  1349.     const int v_shift = ceilf(eh * face);

  1350.     const int ehi = ceilf(eh * (face + 1)) - v_shift;

  1351. 

  1352.     const float uf = 2.f * (i           + 0.5f) / ew  - 1.f;

  1353.     const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;

  1354. 

  1355.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1356. 

  1357.     return 1;

  1358. }

  1359. 

  1360. /**

  1361.  * Calculate 3D coordinates on sphere for corresponding frame position in cubemap6x1 format.

  1362.  *

  1363.  * @param s filter private context

  1364.  * @param i horizontal position on frame [0, width)

  1365.  * @param j vertical position on frame [0, height)

  1366.  * @param width frame width

  1367.  * @param height frame height

  1368.  * @param vec coordinates on sphere

  1369.  */

  1370. static int cube6x1_to_xyz(const V360Context *s,

  1371.                           int i, int j, int width, int height,

  1372.                           float *vec)

  1373. {

  1374.     const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (s->out_width / 6.f)   : 1.f - s->out_pad;

  1375.     const float scaleh = s->fout_pad > 0 ? 1.f - (float)(s->fout_pad) / s->out_height : 1.f - s->out_pad;

  1376. 

  1377.     const float ew = width / 6.f;

  1378.     const float eh = height;

  1379. 

  1380.     const int face = floorf(i / ew);

  1381. 

  1382.     const int u_shift = ceilf(ew * face);

  1383.     const int ewi = ceilf(ew * (face + 1)) - u_shift;

  1384. 

  1385.     const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;

  1386.     const float vf = 2.f * (j           + 0.5f) / eh  - 1.f;

  1387. 

  1388.     cube_to_xyz(s, uf, vf, face, vec, scalew, scaleh);

  1389. 

  1390.     return 1;

  1391. }

  1392. 

  1393. /**

  1394.  * Calculate frame position in cubemap1x6 format for corresponding 3D coordinates on sphere.

  1395.  *

  1396.  * @param s filter private context

  1397.  * @param vec coordinates on sphere

  1398.  * @param width frame width

  1399.  * @param height frame height

  1400.  * @param us horizontal coordinates for interpolation window

  1401.  * @param vs vertical coordinates for interpolation window

  1402.  * @param du horizontal relative coordinate

  1403.  * @param dv vertical relative coordinate

  1404.  */

  1405. static int xyz_to_cube1x6(const V360Context *s,

  1406.                           const float *vec, int width, int height,

  1407.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1408. {

  1409.     const float scalew = s->fin_pad > 0 ? 1.f - (float)(s->fin_pad) / s->in_width : 1.f - s->in_pad;

  1410.     const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_height / 6.f) : 1.f - s->in_pad;

  1411.     const float eh = height / 6.f;

  1412.     const int ewi = width;

  1413.     float uf, vf;

  1414.     int ui, vi;

  1415.     int ehi;

  1416.     int direction, face;

  1417. 

  1418.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1419. 

  1420.     uf *= scalew;

  1421.     vf *= scaleh;

  1422. 

  1423.     face = s->in_cubemap_face_order[direction];

  1424.     ehi = ceilf(eh * (face + 1)) - ceilf(eh * face);

  1425. 

  1426.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1427.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1428. 

  1429.     ui = floorf(uf);

  1430.     vi = floorf(vf);

  1431. 

  1432.     *du = uf - ui;

  1433.     *dv = vf - vi;

  1434. 

  1435.     for (int i = 0; i < 4; i++) {

  1436.         for (int j = 0; j < 4; j++) {

  1437.             int new_ui = ui + j - 1;

  1438.             int new_vi = vi + i - 1;

  1439.             int v_shift;

  1440.             int new_ehi;

  1441. 

  1442.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1443.                 face = s->in_cubemap_face_order[direction];

  1444. 

  1445.                 v_shift = ceilf(eh * face);

  1446.             } else {

  1447.                 uf = 2.f * new_ui / ewi - 1.f;

  1448.                 vf = 2.f * new_vi / ehi - 1.f;

  1449. 

  1450.                 uf /= scalew;

  1451.                 vf /= scaleh;

  1452. 

  1453.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1454. 

  1455.                 uf *= scalew;

  1456.                 vf *= scaleh;

  1457. 

  1458.                 v_shift = ceilf(eh * face);

  1459.                 new_ehi = ceilf(eh * (face + 1)) - v_shift;

  1460. 

  1461.                 new_ui = av_clip(lrintf(0.5f *     ewi * (uf + 1.f)), 0,     ewi - 1);

  1462.                 new_vi = av_clip(lrintf(0.5f * new_ehi * (vf + 1.f)), 0, new_ehi - 1);

  1463.             }

  1464. 

  1465.             us[i][j] =           new_ui;

  1466.             vs[i][j] = v_shift + new_vi;

  1467.         }

  1468.     }

  1469. 

  1470.     return 1;

  1471. }

  1472. 

  1473. /**

  1474.  * Calculate frame position in cubemap6x1 format for corresponding 3D coordinates on sphere.

  1475.  *

  1476.  * @param s filter private context

  1477.  * @param vec coordinates on sphere

  1478.  * @param width frame width

  1479.  * @param height frame height

  1480.  * @param us horizontal coordinates for interpolation window

  1481.  * @param vs vertical coordinates for interpolation window

  1482.  * @param du horizontal relative coordinate

  1483.  * @param dv vertical relative coordinate

  1484.  */

  1485. static int xyz_to_cube6x1(const V360Context *s,

  1486.                           const float *vec, int width, int height,

  1487.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1488. {

  1489.     const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (s->in_width / 6.f)   : 1.f - s->in_pad;

  1490.     const float scaleh = s->fin_pad > 0 ? 1.f - (float)(s->fin_pad) / s->in_height : 1.f - s->in_pad;

  1491.     const float ew = width / 6.f;

  1492.     const int ehi = height;

  1493.     float uf, vf;

  1494.     int ui, vi;

  1495.     int ewi;

  1496.     int direction, face;

  1497. 

  1498.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  1499. 

  1500.     uf *= scalew;

  1501.     vf *= scaleh;

  1502. 

  1503.     face = s->in_cubemap_face_order[direction];

  1504.     ewi = ceilf(ew * (face + 1)) - ceilf(ew * face);

  1505. 

  1506.     uf = 0.5f * ewi * (uf + 1.f) - 0.5f;

  1507.     vf = 0.5f * ehi * (vf + 1.f) - 0.5f;

  1508. 

  1509.     ui = floorf(uf);

  1510.     vi = floorf(vf);

  1511. 

  1512.     *du = uf - ui;

  1513.     *dv = vf - vi;

  1514. 

  1515.     for (int i = 0; i < 4; i++) {

  1516.         for (int j = 0; j < 4; j++) {

  1517.             int new_ui = ui + j - 1;

  1518.             int new_vi = vi + i - 1;

  1519.             int u_shift;

  1520.             int new_ewi;

  1521. 

  1522.             if (new_ui >= 0 && new_ui < ewi && new_vi >= 0 && new_vi < ehi) {

  1523.                 face = s->in_cubemap_face_order[direction];

  1524. 

  1525.                 u_shift = ceilf(ew * face);

  1526.             } else {

  1527.                 uf = 2.f * new_ui / ewi - 1.f;

  1528.                 vf = 2.f * new_vi / ehi - 1.f;

  1529. 

  1530.                 uf /= scalew;

  1531.                 vf /= scaleh;

  1532. 

  1533.                 process_cube_coordinates(s, uf, vf, direction, &uf, &vf, &face);

  1534. 

  1535.                 uf *= scalew;

  1536.                 vf *= scaleh;

  1537. 

  1538.                 u_shift = ceilf(ew * face);

  1539.                 new_ewi = ceilf(ew * (face + 1)) - u_shift;

  1540. 

  1541.                 new_ui = av_clip(lrintf(0.5f * new_ewi * (uf + 1.f)), 0, new_ewi - 1);

  1542.                 new_vi = av_clip(lrintf(0.5f *     ehi * (vf + 1.f)), 0,     ehi - 1);

  1543.             }

  1544. 

  1545.             us[i][j] = u_shift + new_ui;

  1546.             vs[i][j] =           new_vi;

  1547.         }

  1548.     }

  1549. 

  1550.     return 1;

  1551. }

  1552. 

  1553. /**

  1554.  * Calculate 3D coordinates on sphere for corresponding frame position in equirectangular format.

  1555.  *

  1556.  * @param s filter private context

  1557.  * @param i horizontal position on frame [0, width)

  1558.  * @param j vertical position on frame [0, height)

  1559.  * @param width frame width

  1560.  * @param height frame height

  1561.  * @param vec coordinates on sphere

  1562.  */

  1563. static int equirect_to_xyz(const V360Context *s,

  1564.                            int i, int j, int width, int height,

  1565.                            float *vec)

  1566. {

  1567.     const float phi   = ((2.f * i + 0.5f) / width  - 1.f) * M_PI;

  1568.     const float theta = ((2.f * j + 0.5f) / height - 1.f) * M_PI_2;

  1569. 

  1570.     const float sin_phi   = sinf(phi);

  1571.     const float cos_phi   = cosf(phi);

  1572.     const float sin_theta = sinf(theta);

  1573.     const float cos_theta = cosf(theta);

  1574. 

  1575.     vec[0] =  cos_theta * sin_phi;

  1576.     vec[1] = -sin_theta;

  1577.     vec[2] = -cos_theta * cos_phi;

  1578. 

  1579.     return 1;

  1580. }

  1581. 

  1582. /**

  1583.  * Prepare data for processing stereographic output format.

  1584.  *

  1585.  * @param ctx filter context

  1586.  *

  1587.  * @return error code

  1588.  */

  1589. static int prepare_stereographic_out(AVFilterContext *ctx)

  1590. {

  1591.     V360Context *s = ctx->priv;

  1592. 

  1593.     s->flat_range[0] = tanf(FFMIN(s->h_fov, 359.f) * M_PI / 720.f);

  1594.     s->flat_range[1] = tanf(FFMIN(s->v_fov, 359.f) * M_PI / 720.f);

  1595. 

  1596.     return 0;

  1597. }

  1598. 

  1599. /**

  1600.  * Calculate 3D coordinates on sphere for corresponding frame position in stereographic format.

  1601.  *

  1602.  * @param s filter private context

  1603.  * @param i horizontal position on frame [0, width)

  1604.  * @param j vertical position on frame [0, height)

  1605.  * @param width frame width

  1606.  * @param height frame height

  1607.  * @param vec coordinates on sphere

  1608.  */

  1609. static int stereographic_to_xyz(const V360Context *s,

  1610.                                 int i, int j, int width, int height,

  1611.                                 float *vec)

  1612. {

  1613.     const float x = ((2.f * i + 1.f) / width  - 1.f) * s->flat_range[0];

  1614.     const float y = ((2.f * j + 1.f) / height - 1.f) * s->flat_range[1];

  1615.     const float xy = x * x + y * y;

  1616. 

  1617.     vec[0] = 2.f * x / (1.f + xy);

  1618.     vec[1] = (-1.f + xy) / (1.f + xy);

  1619.     vec[2] = 2.f * y / (1.f + xy);

  1620. 

  1621.     normalize_vector(vec);

  1622. 

  1623.     return 1;

  1624. }

  1625. 

  1626. /**

  1627.  * Prepare data for processing stereographic input format.

  1628.  *

  1629.  * @param ctx filter context

  1630.  *

  1631.  * @return error code

  1632.  */

  1633. static int prepare_stereographic_in(AVFilterContext *ctx)

  1634. {

  1635.     V360Context *s = ctx->priv;

  1636. 

  1637.     s->iflat_range[0] = tanf(FFMIN(s->ih_fov, 359.f) * M_PI / 720.f);

  1638.     s->iflat_range[1] = tanf(FFMIN(s->iv_fov, 359.f) * M_PI / 720.f);

  1639. 

  1640.     return 0;

  1641. }

  1642. 

  1643. /**

  1644.  * Calculate frame position in stereographic format for corresponding 3D coordinates on sphere.

  1645.  *

  1646.  * @param s filter private context

  1647.  * @param vec coordinates on sphere

  1648.  * @param width frame width

  1649.  * @param height frame height

  1650.  * @param us horizontal coordinates for interpolation window

  1651.  * @param vs vertical coordinates for interpolation window

  1652.  * @param du horizontal relative coordinate

  1653.  * @param dv vertical relative coordinate

  1654.  */

  1655. static int xyz_to_stereographic(const V360Context *s,

  1656.                                 const float *vec, int width, int height,

  1657.                                 int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1658. {

  1659.     const float x = vec[0] / (1.f - vec[1]) / s->iflat_range[0] * s->input_mirror_modifier[0];

  1660.     const float y = vec[2] / (1.f - vec[1]) / s->iflat_range[1] * s->input_mirror_modifier[1];

  1661.     float uf, vf;

  1662.     int visible, ui, vi;

  1663. 

  1664.     uf = (x + 1.f) * width  / 2.f;

  1665.     vf = (y + 1.f) * height / 2.f;

  1666.     ui = floorf(uf);

  1667.     vi = floorf(vf);

  1668. 

  1669.     visible = isfinite(x) && isfinite(y) && vi >= 0 && vi < height && ui >= 0 && ui < width;

  1670. 

  1671.     *du = visible ? uf - ui : 0.f;

  1672.     *dv = visible ? vf - vi : 0.f;

  1673. 

  1674.     for (int i = 0; i < 4; i++) {

  1675.         for (int j = 0; j < 4; j++) {

  1676.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  1677.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  1678.         }

  1679.     }

  1680. 

  1681.     return visible;

  1682. }

  1683. 

  1684. /**

  1685.  * Calculate frame position in equirectangular format for corresponding 3D coordinates on sphere.

  1686.  *

  1687.  * @param s filter private context

  1688.  * @param vec coordinates on sphere

  1689.  * @param width frame width

  1690.  * @param height frame height

  1691.  * @param us horizontal coordinates for interpolation window

  1692.  * @param vs vertical coordinates for interpolation window

  1693.  * @param du horizontal relative coordinate

  1694.  * @param dv vertical relative coordinate

  1695.  */

  1696. static int xyz_to_equirect(const V360Context *s,

  1697.                            const float *vec, int width, int height,

  1698.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1699. {

  1700.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  1701.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  1702.     float uf, vf;

  1703.     int ui, vi;

  1704. 

  1705.     uf = (phi   / M_PI   + 1.f) * width  / 2.f;

  1706.     vf = (theta / M_PI_2 + 1.f) * height / 2.f;

  1707.     ui = floorf(uf);

  1708.     vi = floorf(vf);

  1709. 

  1710.     *du = uf - ui;

  1711.     *dv = vf - vi;

  1712. 

  1713.     for (int i = 0; i < 4; i++) {

  1714.         for (int j = 0; j < 4; j++) {

  1715.             us[i][j] = mod(ui + j - 1, width);

  1716.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  1717.         }

  1718.     }

  1719. 

  1720.     return 1;

  1721. }

  1722. 

  1723. /**

  1724.  * Prepare data for processing flat input format.

  1725.  *

  1726.  * @param ctx filter context

  1727.  *

  1728.  * @return error code

  1729.  */

  1730. static int prepare_flat_in(AVFilterContext *ctx)

  1731. {

  1732.     V360Context *s = ctx->priv;

  1733. 

  1734.     s->iflat_range[0] = tanf(0.5f * s->ih_fov * M_PI / 180.f);

  1735.     s->iflat_range[1] = tanf(0.5f * s->iv_fov * M_PI / 180.f);

  1736. 

  1737.     return 0;

  1738. }

  1739. 

  1740. /**

  1741.  * Calculate frame position in flat format for corresponding 3D coordinates on sphere.

  1742.  *

  1743.  * @param s filter private context

  1744.  * @param vec coordinates on sphere

  1745.  * @param width frame width

  1746.  * @param height frame height

  1747.  * @param us horizontal coordinates for interpolation window

  1748.  * @param vs vertical coordinates for interpolation window

  1749.  * @param du horizontal relative coordinate

  1750.  * @param dv vertical relative coordinate

  1751.  */

  1752. static int xyz_to_flat(const V360Context *s,

  1753.                        const float *vec, int width, int height,

  1754.                        int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1755. {

  1756.     const float theta = acosf(vec[2]);

  1757.     const float r = tanf(theta);

  1758.     const float rr = fabsf(r) < 1e+6f ? r : hypotf(width, height);

  1759.     const float zf = -vec[2];

  1760.     const float h = hypotf(vec[0], vec[1]);

  1761.     const float c = h <= 1e-6f ? 1.f : rr / h;

  1762.     float uf = -vec[0] * c / s->iflat_range[0] * s->input_mirror_modifier[0];

  1763.     float vf =  vec[1] * c / s->iflat_range[1] * s->input_mirror_modifier[1];

  1764.     int visible, ui, vi;

  1765. 

  1766.     uf = zf >= 0.f ? (uf + 1.f) * width  / 2.f : 0.f;

  1767.     vf = zf >= 0.f ? (vf + 1.f) * height / 2.f : 0.f;

  1768. 

  1769.     ui = floorf(uf);

  1770.     vi = floorf(vf);

  1771. 

  1772.     visible = vi >= 0 && vi < height && ui >= 0 && ui < width && zf >= 0.f;

  1773. 

  1774.     *du = uf - ui;

  1775.     *dv = vf - vi;

  1776. 

  1777.     for (int i = 0; i < 4; i++) {

  1778.         for (int j = 0; j < 4; j++) {

  1779.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  1780.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  1781.         }

  1782.     }

  1783. 

  1784.     return visible;

  1785. }

  1786. 

  1787. /**

  1788.  * Calculate frame position in mercator format for corresponding 3D coordinates on sphere.

  1789.  *

  1790.  * @param s filter private context

  1791.  * @param vec coordinates on sphere

  1792.  * @param width frame width

  1793.  * @param height frame height

  1794.  * @param us horizontal coordinates for interpolation window

  1795.  * @param vs vertical coordinates for interpolation window

  1796.  * @param du horizontal relative coordinate

  1797.  * @param dv vertical relative coordinate

  1798.  */

  1799. static int xyz_to_mercator(const V360Context *s,

  1800.                            const float *vec, int width, int height,

  1801.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1802. {

  1803.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  1804.     const float theta = -vec[1] * s->input_mirror_modifier[1];

  1805.     float uf, vf;

  1806.     int ui, vi;

  1807. 

  1808.     uf = (phi / M_PI + 1.f) * width / 2.f;

  1809.     vf = (av_clipf(logf((1.f + theta) / (1.f - theta)) / (2.f * M_PI), -1.f, 1.f) + 1.f) * height / 2.f;

  1810.     ui = floorf(uf);

  1811.     vi = floorf(vf);

  1812. 

  1813.     *du = uf - ui;

  1814.     *dv = vf - vi;

  1815. 

  1816.     for (int i = 0; i < 4; i++) {

  1817.         for (int j = 0; j < 4; j++) {

  1818.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  1819.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  1820.         }

  1821.     }

  1822. 

  1823.     return 1;

  1824. }

  1825. 

  1826. /**

  1827.  * Calculate 3D coordinates on sphere for corresponding frame position in mercator format.

  1828.  *

  1829.  * @param s filter private context

  1830.  * @param i horizontal position on frame [0, width)

  1831.  * @param j vertical position on frame [0, height)

  1832.  * @param width frame width

  1833.  * @param height frame height

  1834.  * @param vec coordinates on sphere

  1835.  */

  1836. static int mercator_to_xyz(const V360Context *s,

  1837.                            int i, int j, int width, int height,

  1838.                            float *vec)

  1839. {

  1840.     const float phi = ((2.f * i + 1.f) / width  - 1.f) * M_PI + M_PI_2;

  1841.     const float y   = ((2.f * j + 1.f) / height - 1.f) * M_PI;

  1842.     const float div = expf(2.f * y) + 1.f;

  1843. 

  1844.     const float sin_phi   = sinf(phi);

  1845.     const float cos_phi   = cosf(phi);

  1846.     const float sin_theta = -2.f * expf(y) / div;

  1847.     const float cos_theta = -(expf(2.f * y) - 1.f) / div;

  1848. 

  1849.     vec[0] = sin_theta * cos_phi;

  1850.     vec[1] = cos_theta;

  1851.     vec[2] = sin_theta * sin_phi;

  1852. 

  1853.     return 1;

  1854. }

  1855. 

  1856. /**

  1857.  * Calculate frame position in ball format for corresponding 3D coordinates on sphere.

  1858.  *

  1859.  * @param s filter private context

  1860.  * @param vec coordinates on sphere

  1861.  * @param width frame width

  1862.  * @param height frame height

  1863.  * @param us horizontal coordinates for interpolation window

  1864.  * @param vs vertical coordinates for interpolation window

  1865.  * @param du horizontal relative coordinate

  1866.  * @param dv vertical relative coordinate

  1867.  */

  1868. static int xyz_to_ball(const V360Context *s,

  1869.                        const float *vec, int width, int height,

  1870.                        int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1871. {

  1872.     const float l = hypotf(vec[0], vec[1]);

  1873.     const float r = sqrtf(1.f + vec[2]) / M_SQRT2;

  1874.     float uf, vf;

  1875.     int ui, vi;

  1876. 

  1877.     uf = (1.f + r * vec[0] * s->input_mirror_modifier[0] / (l > 0.f ? l : 1.f)) * width  * 0.5f;

  1878.     vf = (1.f - r * vec[1] * s->input_mirror_modifier[1] / (l > 0.f ? l : 1.f)) * height * 0.5f;

  1879. 

  1880.     ui = floorf(uf);

  1881.     vi = floorf(vf);

  1882. 

  1883.     *du = uf - ui;

  1884.     *dv = vf - vi;

  1885. 

  1886.     for (int i = 0; i < 4; i++) {

  1887.         for (int j = 0; j < 4; j++) {

  1888.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  1889.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  1890.         }

  1891.     }

  1892. 

  1893.     return 1;

  1894. }

  1895. 

  1896. /**

  1897.  * Calculate 3D coordinates on sphere for corresponding frame position in ball format.

  1898.  *

  1899.  * @param s filter private context

  1900.  * @param i horizontal position on frame [0, width)

  1901.  * @param j vertical position on frame [0, height)

  1902.  * @param width frame width

  1903.  * @param height frame height

  1904.  * @param vec coordinates on sphere

  1905.  */

  1906. static int ball_to_xyz(const V360Context *s,

  1907.                        int i, int j, int width, int height,

  1908.                        float *vec)

  1909. {

  1910.     const float x = (2.f * i + 1.f) / width  - 1.f;

  1911.     const float y = (2.f * j + 1.f) / height - 1.f;

  1912.     const float l = hypotf(x, y);

  1913. 

  1914.     if (l <= 1.f) {

  1915.         const float z = 2.f * l * sqrtf(1.f - l * l);

  1916. 

  1917.         vec[0] =  z * x / (l > 0.f ? l : 1.f);

  1918.         vec[1] = -z * y / (l > 0.f ? l : 1.f);

  1919.         vec[2] = -1.f + 2.f * l * l;

  1920.     } else {

  1921.         vec[0] =  0.f;

  1922.         vec[1] = -1.f;

  1923.         vec[2] =  0.f;

  1924.         return 0;

  1925.     }

  1926. 

  1927.     return 1;

  1928. }

  1929. 

  1930. /**

  1931.  * Calculate 3D coordinates on sphere for corresponding frame position in hammer format.

  1932.  *

  1933.  * @param s filter private context

  1934.  * @param i horizontal position on frame [0, width)

  1935.  * @param j vertical position on frame [0, height)

  1936.  * @param width frame width

  1937.  * @param height frame height

  1938.  * @param vec coordinates on sphere

  1939.  */

  1940. static int hammer_to_xyz(const V360Context *s,

  1941.                          int i, int j, int width, int height,

  1942.                          float *vec)

  1943. {

  1944.     const float x = ((2.f * i + 1.f) / width  - 1.f);

  1945.     const float y = ((2.f * j + 1.f) / height - 1.f);

  1946. 

  1947.     const float xx = x * x;

  1948.     const float yy = y * y;

  1949. 

  1950.     const float z = sqrtf(1.f - xx * 0.5f - yy * 0.5f);

  1951. 

  1952.     const float a = M_SQRT2 * x * z;

  1953.     const float b = 2.f * z * z - 1.f;

  1954. 

  1955.     const float aa = a * a;

  1956.     const float bb = b * b;

  1957. 

  1958.     const float w = sqrtf(1.f - 2.f * yy * z * z);

  1959. 

  1960.     vec[0] =  w * 2.f * a * b / (aa + bb);

  1961.     vec[1] = -M_SQRT2 * y * z;

  1962.     vec[2] = -w * (bb  - aa) / (aa + bb);

  1963. 

  1964.     normalize_vector(vec);

  1965. 

  1966.     return 1;

  1967. }

  1968. 

  1969. /**

  1970.  * Calculate frame position in hammer format for corresponding 3D coordinates on sphere.

  1971.  *

  1972.  * @param s filter private context

  1973.  * @param vec coordinates on sphere

  1974.  * @param width frame width

  1975.  * @param height frame height

  1976.  * @param us horizontal coordinates for interpolation window

  1977.  * @param vs vertical coordinates for interpolation window

  1978.  * @param du horizontal relative coordinate

  1979.  * @param dv vertical relative coordinate

  1980.  */

  1981. static int xyz_to_hammer(const V360Context *s,

  1982.                          const float *vec, int width, int height,

  1983.                          int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  1984. {

  1985.     const float theta = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  1986. 

  1987.     const float z = sqrtf(1.f + sqrtf(1.f - vec[1] * vec[1]) * cosf(theta * 0.5f));

  1988.     const float x = sqrtf(1.f - vec[1] * vec[1]) * sinf(theta * 0.5f) / z;

  1989.     const float y = -vec[1] / z * s->input_mirror_modifier[1];

  1990.     float uf, vf;

  1991.     int ui, vi;

  1992. 

  1993.     uf = (x + 1.f) * width  / 2.f;

  1994.     vf = (y + 1.f) * height / 2.f;

  1995.     ui = floorf(uf);

  1996.     vi = floorf(vf);

  1997. 

  1998.     *du = uf - ui;

  1999.     *dv = vf - vi;

  2000. 

  2001.     for (int i = 0; i < 4; i++) {

  2002.         for (int j = 0; j < 4; j++) {

  2003.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2004.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2005.         }

  2006.     }

  2007. 

  2008.     return 1;

  2009. }

  2010. 

  2011. /**

  2012.  * Calculate 3D coordinates on sphere for corresponding frame position in sinusoidal format.

  2013.  *

  2014.  * @param s filter private context

  2015.  * @param i horizontal position on frame [0, width)

  2016.  * @param j vertical position on frame [0, height)

  2017.  * @param width frame width

  2018.  * @param height frame height

  2019.  * @param vec coordinates on sphere

  2020.  */

  2021. static int sinusoidal_to_xyz(const V360Context *s,

  2022.                              int i, int j, int width, int height,

  2023.                              float *vec)

  2024. {

  2025.     const float theta = ((2.f * j + 1.f) / height - 1.f) * M_PI_2;

  2026.     const float phi   = ((2.f * i + 1.f) / width  - 1.f) * M_PI / cosf(theta);

  2027. 

  2028.     const float sin_phi   = sinf(phi);

  2029.     const float cos_phi   = cosf(phi);

  2030.     const float sin_theta = sinf(theta);

  2031.     const float cos_theta = cosf(theta);

  2032. 

  2033.     vec[0] =  cos_theta * sin_phi;

  2034.     vec[1] = -sin_theta;

  2035.     vec[2] = -cos_theta * cos_phi;

  2036. 

  2037.     normalize_vector(vec);

  2038. 

  2039.     return 1;

  2040. }

  2041. 

  2042. /**

  2043.  * Calculate frame position in sinusoidal format for corresponding 3D coordinates on sphere.

  2044.  *

  2045.  * @param s filter private context

  2046.  * @param vec coordinates on sphere

  2047.  * @param width frame width

  2048.  * @param height frame height

  2049.  * @param us horizontal coordinates for interpolation window

  2050.  * @param vs vertical coordinates for interpolation window

  2051.  * @param du horizontal relative coordinate

  2052.  * @param dv vertical relative coordinate

  2053.  */

  2054. static int xyz_to_sinusoidal(const V360Context *s,

  2055.                              const float *vec, int width, int height,

  2056.                              int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2057. {

  2058.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  2059.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0] * cosf(theta);

  2060.     float uf, vf;

  2061.     int ui, vi;

  2062. 

  2063.     uf = (phi   / M_PI   + 1.f) * width  / 2.f;

  2064.     vf = (theta / M_PI_2 + 1.f) * height / 2.f;

  2065.     ui = floorf(uf);

  2066.     vi = floorf(vf);

  2067. 

  2068.     *du = uf - ui;

  2069.     *dv = vf - vi;

  2070. 

  2071.     for (int i = 0; i < 4; i++) {

  2072.         for (int j = 0; j < 4; j++) {

  2073.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2074.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2075.         }

  2076.     }

  2077. 

  2078.     return 1;

  2079. }

  2080. 

  2081. /**

  2082.  * Prepare data for processing equi-angular cubemap input format.

  2083.  *

  2084.  * @param ctx filter context

  2085.  *

  2086.  * @return error code

  2087.  */

  2088. static int prepare_eac_in(AVFilterContext *ctx)

  2089. {

  2090.     V360Context *s = ctx->priv;

  2091. 

  2092.     if (s->ih_flip && s->iv_flip) {

  2093.         s->in_cubemap_face_order[RIGHT] = BOTTOM_LEFT;

  2094.         s->in_cubemap_face_order[LEFT]  = BOTTOM_RIGHT;

  2095.         s->in_cubemap_face_order[UP]    = TOP_LEFT;

  2096.         s->in_cubemap_face_order[DOWN]  = TOP_RIGHT;

  2097.         s->in_cubemap_face_order[FRONT] = BOTTOM_MIDDLE;

  2098.         s->in_cubemap_face_order[BACK]  = TOP_MIDDLE;

  2099.     } else if (s->ih_flip) {

  2100.         s->in_cubemap_face_order[RIGHT] = TOP_LEFT;

  2101.         s->in_cubemap_face_order[LEFT]  = TOP_RIGHT;

  2102.         s->in_cubemap_face_order[UP]    = BOTTOM_LEFT;

  2103.         s->in_cubemap_face_order[DOWN]  = BOTTOM_RIGHT;

  2104.         s->in_cubemap_face_order[FRONT] = TOP_MIDDLE;

  2105.         s->in_cubemap_face_order[BACK]  = BOTTOM_MIDDLE;

  2106.     } else if (s->iv_flip) {

  2107.         s->in_cubemap_face_order[RIGHT] = BOTTOM_RIGHT;

  2108.         s->in_cubemap_face_order[LEFT]  = BOTTOM_LEFT;

  2109.         s->in_cubemap_face_order[UP]    = TOP_RIGHT;

  2110.         s->in_cubemap_face_order[DOWN]  = TOP_LEFT;

  2111.         s->in_cubemap_face_order[FRONT] = BOTTOM_MIDDLE;

  2112.         s->in_cubemap_face_order[BACK]  = TOP_MIDDLE;

  2113.     } else {

  2114.         s->in_cubemap_face_order[RIGHT] = TOP_RIGHT;

  2115.         s->in_cubemap_face_order[LEFT]  = TOP_LEFT;

  2116.         s->in_cubemap_face_order[UP]    = BOTTOM_RIGHT;

  2117.         s->in_cubemap_face_order[DOWN]  = BOTTOM_LEFT;

  2118.         s->in_cubemap_face_order[FRONT] = TOP_MIDDLE;

  2119.         s->in_cubemap_face_order[BACK]  = BOTTOM_MIDDLE;

  2120.     }

  2121. 

  2122.     if (s->iv_flip) {

  2123.         s->in_cubemap_face_rotation[TOP_LEFT]      = ROT_270;

  2124.         s->in_cubemap_face_rotation[TOP_MIDDLE]    = ROT_90;

  2125.         s->in_cubemap_face_rotation[TOP_RIGHT]     = ROT_270;

  2126.         s->in_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_0;

  2127.         s->in_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_0;

  2128.         s->in_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_0;

  2129.     } else {

  2130.         s->in_cubemap_face_rotation[TOP_LEFT]      = ROT_0;

  2131.         s->in_cubemap_face_rotation[TOP_MIDDLE]    = ROT_0;

  2132.         s->in_cubemap_face_rotation[TOP_RIGHT]     = ROT_0;

  2133.         s->in_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_270;

  2134.         s->in_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_90;

  2135.         s->in_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_270;

  2136.     }

  2137. 

  2138.     return 0;

  2139. }

  2140. 

  2141. /**

  2142.  * Prepare data for processing equi-angular cubemap output format.

  2143.  *

  2144.  * @param ctx filter context

  2145.  *

  2146.  * @return error code

  2147.  */

  2148. static int prepare_eac_out(AVFilterContext *ctx)

  2149. {

  2150.     V360Context *s = ctx->priv;

  2151. 

  2152.     s->out_cubemap_direction_order[TOP_LEFT]      = LEFT;

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

  2154.     s->out_cubemap_direction_order[TOP_RIGHT]     = RIGHT;

  2155.     s->out_cubemap_direction_order[BOTTOM_LEFT]   = DOWN;

  2156.     s->out_cubemap_direction_order[BOTTOM_MIDDLE] = BACK;

  2157.     s->out_cubemap_direction_order[BOTTOM_RIGHT]  = UP;

  2158. 

  2159.     s->out_cubemap_face_rotation[TOP_LEFT]      = ROT_0;

  2160.     s->out_cubemap_face_rotation[TOP_MIDDLE]    = ROT_0;

  2161.     s->out_cubemap_face_rotation[TOP_RIGHT]     = ROT_0;

  2162.     s->out_cubemap_face_rotation[BOTTOM_LEFT]   = ROT_270;

  2163.     s->out_cubemap_face_rotation[BOTTOM_MIDDLE] = ROT_90;

  2164.     s->out_cubemap_face_rotation[BOTTOM_RIGHT]  = ROT_270;

  2165. 

  2166.     return 0;

  2167. }

  2168. 

  2169. /**

  2170.  * Calculate 3D coordinates on sphere for corresponding frame position in equi-angular cubemap format.

  2171.  *

  2172.  * @param s filter private context

  2173.  * @param i horizontal position on frame [0, width)

  2174.  * @param j vertical position on frame [0, height)

  2175.  * @param width frame width

  2176.  * @param height frame height

  2177.  * @param vec coordinates on sphere

  2178.  */

  2179. static int eac_to_xyz(const V360Context *s,

  2180.                       int i, int j, int width, int height,

  2181.                       float *vec)

  2182. {

  2183.     const float pixel_pad = 2;

  2184.     const float u_pad = pixel_pad / width;

  2185.     const float v_pad = pixel_pad / height;

  2186. 

  2187.     int u_face, v_face, face;

  2188. 

  2189.     float l_x, l_y, l_z;

  2190. 

  2191.     float uf = (i + 0.5f) / width;

  2192.     float vf = (j + 0.5f) / height;

  2193. 

  2194.     // EAC has 2-pixel padding on faces except between faces on the same row

  2195.     // Padding pixels seems not to be stretched with tangent as regular pixels

  2196.     // Formulas below approximate original padding as close as I could get experimentally

  2197. 

  2198.     // Horizontal padding

  2199.     uf = 3.f * (uf - u_pad) / (1.f - 2.f * u_pad);

  2200.     if (uf < 0.f) {

  2201.         u_face = 0;

  2202.         uf -= 0.5f;

  2203.     } else if (uf >= 3.f) {

  2204.         u_face = 2;

  2205.         uf -= 2.5f;

  2206.     } else {

  2207.         u_face = floorf(uf);

  2208.         uf = fmodf(uf, 1.f) - 0.5f;

  2209.     }

  2210. 

  2211.     // Vertical padding

  2212.     v_face = floorf(vf * 2.f);

  2213.     vf = (vf - v_pad - 0.5f * v_face) / (0.5f - 2.f * v_pad) - 0.5f;

  2214. 

  2215.     if (uf >= -0.5f && uf < 0.5f) {

  2216.         uf = tanf(M_PI_2 * uf);

  2217.     } else {

  2218.         uf = 2.f * uf;

  2219.     }

  2220.     if (vf >= -0.5f && vf < 0.5f) {

  2221.         vf = tanf(M_PI_2 * vf);

  2222.     } else {

  2223.         vf = 2.f * vf;

  2224.     }

  2225. 

  2226.     face = u_face + 3 * v_face;

  2227. 

  2228.     switch (face) {

  2229.     case TOP_LEFT:

  2230.         l_x = -1.f;

  2231.         l_y = -vf;

  2232.         l_z = -uf;

  2233.         break;

  2234.     case TOP_MIDDLE:

  2235.         l_x =  uf;

  2236.         l_y = -vf;

  2237.         l_z = -1.f;

  2238.         break;

  2239.     case TOP_RIGHT:

  2240.         l_x =  1.f;

  2241.         l_y = -vf;

  2242.         l_z =  uf;

  2243.         break;

  2244.     case BOTTOM_LEFT:

  2245.         l_x = -vf;

  2246.         l_y = -1.f;

  2247.         l_z =  uf;

  2248.         break;

  2249.     case BOTTOM_MIDDLE:

  2250.         l_x = -vf;

  2251.         l_y =  uf;

  2252.         l_z =  1.f;

  2253.         break;

  2254.     case BOTTOM_RIGHT:

  2255.         l_x = -vf;

  2256.         l_y =  1.f;

  2257.         l_z = -uf;

  2258.         break;

  2259.     default:

  2260.         av_assert0(0);

  2261.     }

  2262. 

  2263.     vec[0] = l_x;

  2264.     vec[1] = l_y;

  2265.     vec[2] = l_z;

  2266. 

  2267.     normalize_vector(vec);

  2268. 

  2269.     return 1;

  2270. }

  2271. 

  2272. /**

  2273.  * Calculate frame position in equi-angular cubemap format for corresponding 3D coordinates on sphere.

  2274.  *

  2275.  * @param s filter private context

  2276.  * @param vec coordinates on sphere

  2277.  * @param width frame width

  2278.  * @param height frame height

  2279.  * @param us horizontal coordinates for interpolation window

  2280.  * @param vs vertical coordinates for interpolation window

  2281.  * @param du horizontal relative coordinate

  2282.  * @param dv vertical relative coordinate

  2283.  */

  2284. static int xyz_to_eac(const V360Context *s,

  2285.                       const float *vec, int width, int height,

  2286.                       int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2287. {

  2288.     const float pixel_pad = 2;

  2289.     const float u_pad = pixel_pad / width;

  2290.     const float v_pad = pixel_pad / height;

  2291. 

  2292.     float uf, vf;

  2293.     int ui, vi;

  2294.     int direction, face;

  2295.     int u_face, v_face;

  2296. 

  2297.     xyz_to_cube(s, vec, &uf, &vf, &direction);

  2298. 

  2299.     face = s->in_cubemap_face_order[direction];

  2300.     u_face = face % 3;

  2301.     v_face = face / 3;

  2302. 

  2303.     uf = M_2_PI * atanf(uf) + 0.5f;

  2304.     vf = M_2_PI * atanf(vf) + 0.5f;

  2305. 

  2306.     // These formulas are inversed from eac_to_xyz ones

  2307.     uf = (uf + u_face) * (1.f - 2.f * u_pad) / 3.f + u_pad;

  2308.     vf = vf * (0.5f - 2.f * v_pad) + v_pad + 0.5f * v_face;

  2309. 

  2310.     uf *= width;

  2311.     vf *= height;

  2312. 

  2313.     uf -= 0.5f;

  2314.     vf -= 0.5f;

  2315. 

  2316.     ui = floorf(uf);

  2317.     vi = floorf(vf);

  2318. 

  2319.     *du = uf - ui;

  2320.     *dv = vf - vi;

  2321. 

  2322.     for (int i = 0; i < 4; i++) {

  2323.         for (int j = 0; j < 4; j++) {

  2324.             us[i][j] = av_clip(ui + j - 1, 0, width  - 1);

  2325.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2326.         }

  2327.     }

  2328. 

  2329.     return 1;

  2330. }

  2331. 

  2332. /**

  2333.  * Prepare data for processing flat output format.

  2334.  *

  2335.  * @param ctx filter context

  2336.  *

  2337.  * @return error code

  2338.  */

  2339. static int prepare_flat_out(AVFilterContext *ctx)

  2340. {

  2341.     V360Context *s = ctx->priv;

  2342. 

  2343.     s->flat_range[0] = tanf(0.5f * s->h_fov * M_PI / 180.f);

  2344.     s->flat_range[1] = tanf(0.5f * s->v_fov * M_PI / 180.f);

  2345. 

  2346.     return 0;

  2347. }

  2348. 

  2349. /**

  2350.  * Calculate 3D coordinates on sphere for corresponding frame position in flat format.

  2351.  *

  2352.  * @param s filter private context

  2353.  * @param i horizontal position on frame [0, width)

  2354.  * @param j vertical position on frame [0, height)

  2355.  * @param width frame width

  2356.  * @param height frame height

  2357.  * @param vec coordinates on sphere

  2358.  */

  2359. static int flat_to_xyz(const V360Context *s,

  2360.                        int i, int j, int width, int height,

  2361.                        float *vec)

  2362. {

  2363.     const float l_x =  s->flat_range[0] * ((2.f * i + 0.5f) / width  - 1.f);

  2364.     const float l_y = -s->flat_range[1] * ((2.f * j + 0.5f) / height - 1.f);

  2365. 

  2366.     vec[0] =  l_x;

  2367.     vec[1] =  l_y;

  2368.     vec[2] = -1.f;

  2369. 

  2370.     normalize_vector(vec);

  2371. 

  2372.     return 1;

  2373. }

  2374. 

  2375. /**

  2376.  * Prepare data for processing fisheye output format.

  2377.  *

  2378.  * @param ctx filter context

  2379.  *

  2380.  * @return error code

  2381.  */

  2382. static int prepare_fisheye_out(AVFilterContext *ctx)

  2383. {

  2384.     V360Context *s = ctx->priv;

  2385. 

  2386.     s->flat_range[0] = s->h_fov / 180.f;

  2387.     s->flat_range[1] = s->v_fov / 180.f;

  2388. 

  2389.     return 0;

  2390. }

  2391. 

  2392. /**

  2393.  * Calculate 3D coordinates on sphere for corresponding frame position in fisheye format.

  2394.  *

  2395.  * @param s filter private context

  2396.  * @param i horizontal position on frame [0, width)

  2397.  * @param j vertical position on frame [0, height)

  2398.  * @param width frame width

  2399.  * @param height frame height

  2400.  * @param vec coordinates on sphere

  2401.  */

  2402. static int fisheye_to_xyz(const V360Context *s,

  2403.                           int i, int j, int width, int height,

  2404.                           float *vec)

  2405. {

  2406.     const float uf = s->flat_range[0] * ((2.f * i) / width  - 1.f);

  2407.     const float vf = s->flat_range[1] * ((2.f * j + 1.f) / height - 1.f);

  2408. 

  2409.     const float phi   = -atan2f(vf, uf);

  2410.     const float theta = -M_PI_2 * (1.f - hypotf(uf, vf));

  2411. 

  2412.     vec[0] = cosf(theta) * cosf(phi);

  2413.     vec[1] = cosf(theta) * sinf(phi);

  2414.     vec[2] = sinf(theta);

  2415. 

  2416.     normalize_vector(vec);

  2417. 

  2418.     return 1;

  2419. }

  2420. 

  2421. /**

  2422.  * Prepare data for processing fisheye input format.

  2423.  *

  2424.  * @param ctx filter context

  2425.  *

  2426.  * @return error code

  2427.  */

  2428. static int prepare_fisheye_in(AVFilterContext *ctx)

  2429. {

  2430.     V360Context *s = ctx->priv;

  2431. 

  2432.     s->iflat_range[0] = s->ih_fov / 180.f;

  2433.     s->iflat_range[1] = s->iv_fov / 180.f;

  2434. 

  2435.     return 0;

  2436. }

  2437. 

  2438. /**

  2439.  * Calculate frame position in fisheye format for corresponding 3D coordinates on sphere.

  2440.  *

  2441.  * @param s filter private context

  2442.  * @param vec coordinates on sphere

  2443.  * @param width frame width

  2444.  * @param height frame height

  2445.  * @param us horizontal coordinates for interpolation window

  2446.  * @param vs vertical coordinates for interpolation window

  2447.  * @param du horizontal relative coordinate

  2448.  * @param dv vertical relative coordinate

  2449.  */

  2450. static int xyz_to_fisheye(const V360Context *s,

  2451.                           const float *vec, int width, int height,

  2452.                           int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2453. {

  2454.     const float phi   = -atan2f(hypotf(vec[0], vec[1]), -vec[2]) / M_PI;

  2455.     const float theta = -atan2f(vec[0], vec[1]);

  2456. 

  2457.     float uf = sinf(theta) * phi * s->input_mirror_modifier[0] / s->iflat_range[0];

  2458.     float vf = cosf(theta) * phi * s->input_mirror_modifier[1] / s->iflat_range[1];

  2459. 

  2460.     const int visible = hypotf(uf, vf) <= 0.5f;

  2461.     int ui, vi;

  2462. 

  2463.     uf = (uf + 0.5f) * width;

  2464.     vf = (vf + 0.5f) * height;

  2465. 

  2466.     ui = floorf(uf);

  2467.     vi = floorf(vf);

  2468. 

  2469.     *du = visible ? uf - ui : 0.f;

  2470.     *dv = visible ? vf - vi : 0.f;

  2471. 

  2472.     for (int i = 0; i < 4; i++) {

  2473.         for (int j = 0; j < 4; j++) {

  2474.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  2475.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  2476.         }

  2477.     }

  2478. 

  2479.     return visible;

  2480. }

  2481. 

  2482. /**

  2483.  * Calculate 3D coordinates on sphere for corresponding frame position in pannini format.

  2484.  *

  2485.  * @param s filter private context

  2486.  * @param i horizontal position on frame [0, width)

  2487.  * @param j vertical position on frame [0, height)

  2488.  * @param width frame width

  2489.  * @param height frame height

  2490.  * @param vec coordinates on sphere

  2491.  */

  2492. static int pannini_to_xyz(const V360Context *s,

  2493.                           int i, int j, int width, int height,

  2494.                           float *vec)

  2495. {

  2496.     const float uf = ((2.f * i + 1.f) / width  - 1.f);

  2497.     const float vf = ((2.f * j + 1.f) / height - 1.f);

  2498. 

  2499.     const float d = s->h_fov;

  2500.     const float k = uf * uf / ((d + 1.f) * (d + 1.f));

  2501.     const float dscr = k * k * d * d - (k + 1.f) * (k * d * d - 1.f);

  2502.     const float clon = (-k * d + sqrtf(dscr)) / (k + 1.f);

  2503.     const float S = (d + 1.f) / (d + clon);

  2504.     const float lon = -(M_PI + atan2f(uf, S * clon));

  2505.     const float lat = -atan2f(vf, S);

  2506. 

  2507.     vec[0] = sinf(lon) * cosf(lat);

  2508.     vec[1] = sinf(lat);

  2509.     vec[2] = cosf(lon) * cosf(lat);

  2510. 

  2511.     normalize_vector(vec);

  2512. 

  2513.     return 1;

  2514. }

  2515. 

  2516. /**

  2517.  * Prepare data for processing cylindrical output format.

  2518.  *

  2519.  * @param ctx filter context

  2520.  *

  2521.  * @return error code

  2522.  */

  2523. static int prepare_cylindrical_out(AVFilterContext *ctx)

  2524. {

  2525.     V360Context *s = ctx->priv;

  2526. 

  2527.     s->flat_range[0] = M_PI * s->h_fov / 360.f;

  2528.     s->flat_range[1] = tanf(0.5f * s->v_fov * M_PI / 180.f);

  2529. 

  2530.     return 0;

  2531. }

  2532. 

  2533. /**

  2534.  * Calculate 3D coordinates on sphere for corresponding frame position in cylindrical format.

  2535.  *

  2536.  * @param s filter private context

  2537.  * @param i horizontal position on frame [0, width)

  2538.  * @param j vertical position on frame [0, height)

  2539.  * @param width frame width

  2540.  * @param height frame height

  2541.  * @param vec coordinates on sphere

  2542.  */

  2543. static int cylindrical_to_xyz(const V360Context *s,

  2544.                               int i, int j, int width, int height,

  2545.                               float *vec)

  2546. {

  2547.     const float uf = s->flat_range[0] * ((2.f * i + 1.f) / width  - 1.f);

  2548.     const float vf = s->flat_range[1] * ((2.f * j + 1.f) / height - 1.f);

  2549. 

  2550.     const float phi   = uf;

  2551.     const float theta = atanf(vf);

  2552. 

  2553.     const float sin_phi   = sinf(phi);

  2554.     const float cos_phi   = cosf(phi);

  2555.     const float sin_theta = sinf(theta);

  2556.     const float cos_theta = cosf(theta);

  2557. 

  2558.     vec[0] =  cos_theta * sin_phi;

  2559.     vec[1] = -sin_theta;

  2560.     vec[2] = -cos_theta * cos_phi;

  2561. 

  2562.     normalize_vector(vec);

  2563. 

  2564.     return 1;

  2565. }

  2566. 

  2567. /**

  2568.  * Prepare data for processing cylindrical input format.

  2569.  *

  2570.  * @param ctx filter context

  2571.  *

  2572.  * @return error code

  2573.  */

  2574. static int prepare_cylindrical_in(AVFilterContext *ctx)

  2575. {

  2576.     V360Context *s = ctx->priv;

  2577. 

  2578.     s->iflat_range[0] = M_PI * s->ih_fov / 360.f;

  2579.     s->iflat_range[1] = tanf(0.5f * s->iv_fov * M_PI / 180.f);

  2580. 

  2581.     return 0;

  2582. }

  2583. 

  2584. /**

  2585.  * Calculate frame position in cylindrical format for corresponding 3D coordinates on sphere.

  2586.  *

  2587.  * @param s filter private context

  2588.  * @param vec coordinates on sphere

  2589.  * @param width frame width

  2590.  * @param height frame height

  2591.  * @param us horizontal coordinates for interpolation window

  2592.  * @param vs vertical coordinates for interpolation window

  2593.  * @param du horizontal relative coordinate

  2594.  * @param dv vertical relative coordinate

  2595.  */

  2596. static int xyz_to_cylindrical(const V360Context *s,

  2597.                               const float *vec, int width, int height,

  2598.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2599. {

  2600.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0] / s->iflat_range[0];

  2601.     const float theta = atan2f(-vec[1], hypotf(vec[0], vec[2])) * s->input_mirror_modifier[1] / s->iflat_range[1];

  2602.     int visible, ui, vi;

  2603.     float uf, vf;

  2604. 

  2605.     uf = (phi + 1.f) * (width - 1) / 2.f;

  2606.     vf = (tanf(theta) + 1.f) * height / 2.f;

  2607.     ui = floorf(uf);

  2608.     vi = floorf(vf);

  2609. 

  2610.     visible = vi >= 0 && vi < height && ui >= 0 && ui < width &&

  2611.               theta <=  M_PI * s->iv_fov / 180.f &&

  2612.               theta >= -M_PI * s->iv_fov / 180.f;

  2613. 

  2614.     *du = uf - ui;

  2615.     *dv = vf - vi;

  2616. 

  2617.     for (int i = 0; i < 4; i++) {

  2618.         for (int j = 0; j < 4; j++) {

  2619.             us[i][j] = visible ? av_clip(ui + j - 1, 0, width  - 1) : 0;

  2620.             vs[i][j] = visible ? av_clip(vi + i - 1, 0, height - 1) : 0;

  2621.         }

  2622.     }

  2623. 

  2624.     return visible;

  2625. }

  2626. 

  2627. /**

  2628.  * Calculate 3D coordinates on sphere for corresponding frame position in perspective format.

  2629.  *

  2630.  * @param s filter private context

  2631.  * @param i horizontal position on frame [0, width)

  2632.  * @param j vertical position on frame [0, height)

  2633.  * @param width frame width

  2634.  * @param height frame height

  2635.  * @param vec coordinates on sphere

  2636.  */

  2637. static int perspective_to_xyz(const V360Context *s,

  2638.                               int i, int j, int width, int height,

  2639.                               float *vec)

  2640. {

  2641.     const float uf = ((2.f * i + 1.f) / width  - 1.f);

  2642.     const float vf = ((2.f * j + 1.f) / height - 1.f);

  2643.     const float rh = hypotf(uf, vf);

  2644.     const float sinzz = 1.f - rh * rh;

  2645.     const float h = 1.f + s->v_fov;

  2646.     const float sinz = (h - sqrtf(sinzz)) / (h / rh + rh / h);

  2647.     const float sinz2 = sinz * sinz;

  2648. 

  2649.     if (sinz2 <= 1.f) {

  2650.         const float cosz = sqrtf(1.f - sinz2);

  2651. 

  2652.         const float theta = asinf(cosz);

  2653.         const float phi   = atan2f(uf, vf);

  2654. 

  2655.         const float sin_phi   = sinf(phi);

  2656.         const float cos_phi   = cosf(phi);

  2657.         const float sin_theta = sinf(theta);

  2658.         const float cos_theta = cosf(theta);

  2659. 

  2660.         vec[0] =  cos_theta * sin_phi;

  2661.         vec[1] =  sin_theta;

  2662.         vec[2] = -cos_theta * cos_phi;

  2663.     } else {

  2664.         vec[0] =  0.f;

  2665.         vec[1] = -1.f;

  2666.         vec[2] =  0.f;

  2667.         return 0;

  2668.     }

  2669. 

  2670.     normalize_vector(vec);

  2671.     return 1;

  2672. }

  2673. 

  2674. /**

  2675.  * Calculate 3D coordinates on sphere for corresponding frame position in tetrahedron format.

  2676.  *

  2677.  * @param s filter private context

  2678.  * @param i horizontal position on frame [0, width)

  2679.  * @param j vertical position on frame [0, height)

  2680.  * @param width frame width

  2681.  * @param height frame height

  2682.  * @param vec coordinates on sphere

  2683.  */

  2684. static int tetrahedron_to_xyz(const V360Context *s,

  2685.                               int i, int j, int width, int height,

  2686.                               float *vec)

  2687. {

  2688.     const float uf = (float)i / width;

  2689.     const float vf = (float)j / height;

  2690. 

  2691.     vec[0] = uf < 0.5f ? uf * 4.f - 1.f : 3.f - uf * 4.f;

  2692.     vec[1] = 1.f - vf * 2.f;

  2693.     vec[2] = 2.f * fabsf(1.f - fabsf(1.f - uf * 2.f + vf)) - 1.f;

  2694. 

  2695.     normalize_vector(vec);

  2696. 

  2697.     return 1;

  2698. }

  2699. 

  2700. /**

  2701.  * Calculate frame position in tetrahedron format for corresponding 3D coordinates on sphere.

  2702.  *

  2703.  * @param s filter private context

  2704.  * @param vec coordinates on sphere

  2705.  * @param width frame width

  2706.  * @param height frame height

  2707.  * @param us horizontal coordinates for interpolation window

  2708.  * @param vs vertical coordinates for interpolation window

  2709.  * @param du horizontal relative coordinate

  2710.  * @param dv vertical relative coordinate

  2711.  */

  2712. static int xyz_to_tetrahedron(const V360Context *s,

  2713.                               const float *vec, int width, int height,

  2714.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2715. {

  2716.     float d = 0.5f * (vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2]);

  2717. 

  2718.     const float d0 = (vec[0] * 0.5f + vec[1] * 0.5f + vec[2] *-0.5f) / d;

  2719.     const float d1 = (vec[0] *-0.5f + vec[1] *-0.5f + vec[2] *-0.5f) / d;

  2720.     const float d2 = (vec[0] * 0.5f + vec[1] *-0.5f + vec[2] * 0.5f) / d;

  2721.     const float d3 = (vec[0] *-0.5f + vec[1] * 0.5f + vec[2] * 0.5f) / d;

  2722. 

  2723.     float uf, vf, x, y, z;

  2724.     int ui, vi;

  2725. 

  2726.     d = FFMAX(d0, FFMAX3(d1, d2, d3));

  2727. 

  2728.     x =  vec[0] / d;

  2729.     y =  vec[1] / d;

  2730.     z = -vec[2] / d;

  2731. 

  2732.     vf = 0.5f - y * 0.5f * s->input_mirror_modifier[1];

  2733. 

  2734.     if ((x + y >= 0.f &&  y + z >= 0.f && -z - x <= 0.f) ||

  2735.         (x + y <= 0.f && -y + z >= 0.f &&  z - x >= 0.f)) {

  2736.         uf = 0.25f * x * s->input_mirror_modifier[0] + 0.25f;

  2737.     }  else {

  2738.         uf = 0.75f - 0.25f * x * s->input_mirror_modifier[0];

  2739.     }

  2740. 

  2741.     uf *= width;

  2742.     vf *= height;

  2743. 

  2744.     ui = floorf(uf);

  2745.     vi = floorf(vf);

  2746. 

  2747.     *du = uf - ui;

  2748.     *dv = vf - vi;

  2749. 

  2750.     for (int i = 0; i < 4; i++) {

  2751.         for (int j = 0; j < 4; j++) {

  2752.             us[i][j] = mod(ui + j - 1, width);

  2753.             vs[i][j] = av_clip(vi + i - 1, 0, height - 1);

  2754.         }

  2755.     }

  2756. 

  2757.     return 1;

  2758. }

  2759. 

  2760. /**

  2761.  * Calculate 3D coordinates on sphere for corresponding frame position in dual fisheye format.

  2762.  *

  2763.  * @param s filter private context

  2764.  * @param i horizontal position on frame [0, width)

  2765.  * @param j vertical position on frame [0, height)

  2766.  * @param width frame width

  2767.  * @param height frame height

  2768.  * @param vec coordinates on sphere

  2769.  */

  2770. static int dfisheye_to_xyz(const V360Context *s,

  2771.                            int i, int j, int width, int height,

  2772.                            float *vec)

  2773. {

  2774.     const float scale = 1.f + s->out_pad;

  2775. 

  2776.     const float ew = width / 2.f;

  2777.     const float eh = height;

  2778. 

  2779.     const int ei = i >= ew ? i - ew : i;

  2780.     const float m = i >= ew ? -1.f : 1.f;

  2781. 

  2782.     const float uf = ((2.f * ei) / ew - 1.f) * scale;

  2783.     const float vf = ((2.f * j + 1.f) / eh - 1.f) * scale;

  2784. 

  2785.     const float h     = hypotf(uf, vf);

  2786.     const float lh    = h > 0.f ? h : 1.f;

  2787.     const float theta = m * M_PI_2 * (1.f - h);

  2788. 

  2789.     const float sin_theta = sinf(theta);

  2790.     const float cos_theta = cosf(theta);

  2791. 

  2792.     vec[0] = cos_theta * m * -uf / lh;

  2793.     vec[1] = cos_theta *     -vf / lh;

  2794.     vec[2] = sin_theta;

  2795. 

  2796.     normalize_vector(vec);

  2797. 

  2798.     return 1;

  2799. }

  2800. 

  2801. /**

  2802.  * Calculate frame position in dual fisheye format for corresponding 3D coordinates on sphere.

  2803.  *

  2804.  * @param s filter private context

  2805.  * @param vec coordinates on sphere

  2806.  * @param width frame width

  2807.  * @param height frame height

  2808.  * @param us horizontal coordinates for interpolation window

  2809.  * @param vs vertical coordinates for interpolation window

  2810.  * @param du horizontal relative coordinate

  2811.  * @param dv vertical relative coordinate

  2812.  */

  2813. static int xyz_to_dfisheye(const V360Context *s,

  2814.                            const float *vec, int width, int height,

  2815.                            int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2816. {

  2817.     const float scale = 1.f - s->in_pad;

  2818. 

  2819.     const float ew = width / 2.f;

  2820.     const float eh = height;

  2821. 

  2822.     const float h     = hypotf(vec[0], vec[1]);

  2823.     const float lh    = h > 0.f ? h : 1.f;

  2824.     const float theta = acosf(fabsf(vec[2])) / M_PI;

  2825. 

  2826.     float uf = (theta * (-vec[0] / lh) * s->input_mirror_modifier[0] * scale + 0.5f) * ew;

  2827.     float vf = (theta * (-vec[1] / lh) * s->input_mirror_modifier[1] * scale + 0.5f) * eh;

  2828. 

  2829.     int ui, vi;

  2830.     int u_shift;

  2831. 

  2832.     if (vec[2] >= 0.f) {

  2833.         u_shift = 0;

  2834.     } else {

  2835.         u_shift = ceilf(ew);

  2836.         uf = ew - uf;

  2837.     }

  2838. 

  2839.     ui = floorf(uf);

  2840.     vi = floorf(vf);

  2841. 

  2842.     *du = uf - ui;

  2843.     *dv = vf - vi;

  2844. 

  2845.     for (int i = 0; i < 4; i++) {

  2846.         for (int j = 0; j < 4; j++) {

  2847.             us[i][j] = av_clip(u_shift + ui + j - 1, 0, width  - 1);

  2848.             vs[i][j] = av_clip(          vi + i - 1, 0, height - 1);

  2849.         }

  2850.     }

  2851. 

  2852.     return 1;

  2853. }

  2854. 

  2855. /**

  2856.  * Calculate 3D coordinates on sphere for corresponding frame position in barrel facebook's format.

  2857.  *

  2858.  * @param s filter private context

  2859.  * @param i horizontal position on frame [0, width)

  2860.  * @param j vertical position on frame [0, height)

  2861.  * @param width frame width

  2862.  * @param height frame height

  2863.  * @param vec coordinates on sphere

  2864.  */

  2865. static int barrel_to_xyz(const V360Context *s,

  2866.                          int i, int j, int width, int height,

  2867.                          float *vec)

  2868. {

  2869.     const float scale = 0.99f;

  2870.     float l_x, l_y, l_z;

  2871. 

  2872.     if (i < 4 * width / 5) {

  2873.         const float theta_range = M_PI_4;

  2874. 

  2875.         const int ew = 4 * width / 5;

  2876.         const int eh = height;

  2877. 

  2878.         const float phi   = ((2.f * i) / ew - 1.f) * M_PI        / scale;

  2879.         const float theta = ((2.f * j) / eh - 1.f) * theta_range / scale;

  2880. 

  2881.         const float sin_phi   = sinf(phi);

  2882.         const float cos_phi   = cosf(phi);

  2883.         const float sin_theta = sinf(theta);

  2884.         const float cos_theta = cosf(theta);

  2885. 

  2886.         l_x =  cos_theta * sin_phi;

  2887.         l_y = -sin_theta;

  2888.         l_z = -cos_theta * cos_phi;

  2889.     } else {

  2890.         const int ew = width  / 5;

  2891.         const int eh = height / 2;

  2892. 

  2893.         float uf, vf;

  2894. 

  2895.         if (j < eh) {   // UP

  2896.             uf = 2.f * (i - 4 * ew) / ew - 1.f;

  2897.             vf = 2.f * (j         ) / eh - 1.f;

  2898. 

  2899.             uf /= scale;

  2900.             vf /= scale;

  2901. 

  2902.             l_x =  uf;

  2903.             l_y =  1.f;

  2904.             l_z = -vf;

  2905.         } else {            // DOWN

  2906.             uf = 2.f * (i - 4 * ew) / ew - 1.f;

  2907.             vf = 2.f * (j -     eh) / eh - 1.f;

  2908. 

  2909.             uf /= scale;

  2910.             vf /= scale;

  2911. 

  2912.             l_x =  uf;

  2913.             l_y = -1.f;

  2914.             l_z =  vf;

  2915.         }

  2916.     }

  2917. 

  2918.     vec[0] = l_x;

  2919.     vec[1] = l_y;

  2920.     vec[2] = l_z;

  2921. 

  2922.     normalize_vector(vec);

  2923. 

  2924.     return 1;

  2925. }

  2926. 

  2927. /**

  2928.  * Calculate frame position in barrel facebook's format for corresponding 3D coordinates on sphere.

  2929.  *

  2930.  * @param s filter private context

  2931.  * @param vec coordinates on sphere

  2932.  * @param width frame width

  2933.  * @param height frame height

  2934.  * @param us horizontal coordinates for interpolation window

  2935.  * @param vs vertical coordinates for interpolation window

  2936.  * @param du horizontal relative coordinate

  2937.  * @param dv vertical relative coordinate

  2938.  */

  2939. static int xyz_to_barrel(const V360Context *s,

  2940.                          const float *vec, int width, int height,

  2941.                          int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  2942. {

  2943.     const float scale = 0.99f;

  2944. 

  2945.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  2946.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  2947.     const float theta_range = M_PI_4;

  2948. 

  2949.     int ew, eh;

  2950.     int u_shift, v_shift;

  2951.     float uf, vf;

  2952.     int ui, vi;

  2953. 

  2954.     if (theta > -theta_range && theta < theta_range) {

  2955.         ew = 4 * width / 5;

  2956.         eh = height;

  2957. 

  2958.         u_shift = s->ih_flip ? width / 5 : 0;

  2959.         v_shift = 0;

  2960. 

  2961.         uf = (phi   / M_PI        * scale + 1.f) * ew / 2.f;

  2962.         vf = (theta / theta_range * scale + 1.f) * eh / 2.f;

  2963.     } else {

  2964.         ew = width  / 5;

  2965.         eh = height / 2;

  2966. 

  2967.         u_shift = s->ih_flip ? 0 : 4 * ew;

  2968. 

  2969.         if (theta < 0.f) {  // UP

  2970.             uf =  vec[0] / vec[1];

  2971.             vf = -vec[2] / vec[1];

  2972.             v_shift = 0;

  2973.         } else {            // DOWN

  2974.             uf = -vec[0] / vec[1];

  2975.             vf = -vec[2] / vec[1];

  2976.             v_shift = eh;

  2977.         }

  2978. 

  2979.         uf *= s->input_mirror_modifier[0] * s->input_mirror_modifier[1];

  2980.         vf *= s->input_mirror_modifier[1];

  2981. 

  2982.         uf = 0.5f * ew * (uf * scale + 1.f);

  2983.         vf = 0.5f * eh * (vf * scale + 1.f);

  2984.     }

  2985. 

  2986.     ui = floorf(uf);

  2987.     vi = floorf(vf);

  2988. 

  2989.     *du = uf - ui;

  2990.     *dv = vf - vi;

  2991. 

  2992.     for (int i = 0; i < 4; i++) {

  2993.         for (int j = 0; j < 4; j++) {

  2994.             us[i][j] = u_shift + av_clip(ui + j - 1, 0, ew - 1);

  2995.             vs[i][j] = v_shift + av_clip(vi + i - 1, 0, eh - 1);

  2996.         }

  2997.     }

  2998. 

  2999.     return 1;

  3000. }

  3001. 

  3002. /**

  3003.  * Calculate frame position in barrel split facebook's format for corresponding 3D coordinates on sphere.

  3004.  *

  3005.  * @param s filter private context

  3006.  * @param vec coordinates on sphere

  3007.  * @param width frame width

  3008.  * @param height frame height

  3009.  * @param us horizontal coordinates for interpolation window

  3010.  * @param vs vertical coordinates for interpolation window

  3011.  * @param du horizontal relative coordinate

  3012.  * @param dv vertical relative coordinate

  3013.  */

  3014. static int xyz_to_barrelsplit(const V360Context *s,

  3015.                               const float *vec, int width, int height,

  3016.                               int16_t us[4][4], int16_t vs[4][4], float *du, float *dv)

  3017. {

  3018.     const float phi   = atan2f(vec[0], -vec[2]) * s->input_mirror_modifier[0];

  3019.     const float theta = asinf(-vec[1]) * s->input_mirror_modifier[1];

  3020. 

  3021.     const float theta_range = M_PI_4;

  3022. 

  3023.     int ew, eh;

  3024.     int u_shift, v_shift;

  3025.     float uf, vf;

  3026.     int ui, vi;

  3027. 

  3028.     if (theta >= -theta_range && theta <= theta_range) {

  3029.         const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (width * 2.f / 3.f) : 1.f - s->in_pad;

  3030.         const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (height / 2.f) : 1.f - s->in_pad;

  3031. 

  3032.         ew = width / 3 * 2;

  3033.         eh = height / 2;

  3034. 

  3035.         u_shift = s->ih_flip ? width / 3 : 0;

  3036.         v_shift = phi >= M_PI_2 || phi < -M_PI_2 ? eh : 0;

  3037. 

  3038.         uf = fmodf(phi, M_PI_2) / M_PI_2;

  3039.         vf = theta / M_PI_4;

  3040. 

  3041.         if (v_shift)

  3042.             uf = uf >= 0.f ? fmodf(uf - 1.f, 1.f) : fmodf(uf + 1.f, 1.f);

  3043. 

  3044.         uf = (uf * scalew + 1.f) * width  / 3.f;

  3045.         vf = (vf * scaleh + 1.f) * height / 4.f;

  3046.     } else {

  3047.         const float scalew = s->fin_pad > 0 ? 1.f - s->fin_pad / (width  / 3.f) : 1.f - s->in_pad;

  3048.         const float scaleh = s->fin_pad > 0 ? 1.f - s->fin_pad / (height / 4.f) : 1.f - s->in_pad;

  3049.         int v_offset = 0;

  3050. 

  3051.         ew = width  / 3;

  3052.         eh = height / 4;

  3053. 

  3054.         u_shift = s->ih_flip ? 0 : 2 * ew;

  3055. 

  3056.         if (theta <= 0.f && theta >= -M_PI_2 &&

  3057.             phi <= M_PI_2 && phi >= -M_PI_2) {

  3058.             uf =  vec[0] / vec[1];

  3059.             vf = -vec[2] / vec[1];

  3060.             v_shift = 0;

  3061.             v_offset = -eh;

  3062.         } else if (theta >= 0.f && theta <= M_PI_2 &&

  3063.                    phi <= M_PI_2 && phi >= -M_PI_2) {

  3064.             uf = -vec[0] / vec[1];

  3065.             vf = -vec[2] / vec[1];

  3066.             v_shift = height * 0.25f;

  3067.         } else if (theta <= 0.f && theta >= -M_PI_2) {

  3068.             uf = -vec[0] / vec[1];

  3069.             vf =  vec[2] / vec[1];

  3070.             v_shift = height * 0.5f;

  3071.             v_offset = -eh;

  3072.         } else {

  3073.             uf = vec[0] / vec[1];

  3074.             vf = vec[2] / vec[1];

  3075.             v_shift = height * 0.75f;

  3076.         }

  3077. 

  3078.         uf *= s->input_mirror_modifier[0] * s->input_mirror_modifier[1];

  3079.         vf *= s->input_mirror_modifier[1];

  3080. 

  3081.         uf = 0.5f * width / 3.f * (uf * scalew + 1.f);

  3082.         vf = height * 0.25f * (vf * scaleh + 1.f) + v_offset;

  3083.     }

  3084. 

  3085.     ui = floorf(uf);

  3086.     vi = floorf(vf);

  3087. 

  3088.     *du = uf - ui;

  3089.     *dv = vf - vi;

  3090. 

  3091.     for (int i = 0; i < 4; i++) {

  3092.         for (int j = 0; j < 4; j++) {

  3093.             us[i][j] = u_shift + av_clip(ui + j - 1, 0, ew - 1);

  3094.             vs[i][j] = v_shift + av_clip(vi + i - 1, 0, eh - 1);

  3095.         }

  3096.     }

  3097. 

  3098.     return 1;

  3099. }

  3100. 

  3101. /**

  3102.  * Calculate 3D coordinates on sphere for corresponding frame position in barrel split facebook's format.

  3103.  *

  3104.  * @param s filter private context

  3105.  * @param i horizontal position on frame [0, width)

  3106.  * @param j vertical position on frame [0, height)

  3107.  * @param width frame width

  3108.  * @param height frame height

  3109.  * @param vec coordinates on sphere

  3110.  */

  3111. static int barrelsplit_to_xyz(const V360Context *s,

  3112.                               int i, int j, int width, int height,

  3113.                               float *vec)

  3114. {

  3115.     const float x = (i + 0.5f) / width;

  3116.     const float y = (j + 0.5f) / height;

  3117.     float l_x, l_y, l_z;

  3118. 

  3119.     if (x < 2.f / 3.f) {

  3120.         const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (width * 2.f / 3.f) : 1.f - s->out_pad;

  3121.         const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (height / 2.f) : 1.f - s->out_pad;

  3122. 

  3123.         const float back = floorf(y * 2.f);

  3124. 

  3125.         const float phi   = ((3.f / 2.f * x - 0.5f) / scalew - back + 1.f) * M_PI;

  3126.         const float theta = (y - 0.25f - 0.5f * back) / scaleh * M_PI;

  3127. 

  3128.         const float sin_phi   = sinf(phi);

  3129.         const float cos_phi   = cosf(phi);

  3130.         const float sin_theta = sinf(theta);

  3131.         const float cos_theta = cosf(theta);

  3132. 

  3133.         l_x = -cos_theta * sin_phi;

  3134.         l_y = -sin_theta;

  3135.         l_z =  cos_theta * cos_phi;

  3136.     } else {

  3137.         const float scalew = s->fout_pad > 0 ? 1.f - s->fout_pad / (width  / 3.f) : 1.f - s->out_pad;

  3138.         const float scaleh = s->fout_pad > 0 ? 1.f - s->fout_pad / (height / 4.f) : 1.f - s->out_pad;

  3139. 

  3140.         const int face = floorf(y * 4.f);

  3141.         float uf, vf;

  3142. 

  3143.         uf = x * 3.f - 2.f;

  3144. 

  3145.         switch (face) {

  3146.         case 0:

  3147.             vf = y * 2.f;

  3148.             uf = 1.f - uf;

  3149.             vf = 0.5f - vf;

  3150. 

  3151.             l_x = (0.5f - uf) / scalew;

  3152.             l_y =  0.5f;

  3153.             l_z = (-0.5f + vf) / scaleh;

  3154.             break;

  3155.         case 1:

  3156.             vf = y * 2.f;

  3157.             uf = 1.f - uf;

  3158.             vf = 1.f - (vf - 0.5f);

  3159. 

  3160.             l_x = (0.5f - uf) / scalew;

  3161.             l_y = -0.5f;

  3162.             l_z = (0.5f - vf) / scaleh;

  3163.             break;

  3164.         case 2:

  3165.             vf = y * 2.f - 0.5f;

  3166.             vf = 1.f - (1.f - vf);

  3167. 

  3168.             l_x = (0.5f - uf) / scalew;

  3169.             l_y = 0.5f;

  3170.             l_z = (-0.5f + vf) / scaleh;

  3171.             break;

  3172.         case 3:

  3173.             vf = y * 2.f - 1.5f;

  3174. 

  3175.             l_x = (0.5f - uf) / scalew;

  3176.             l_y = -0.5f;

  3177.             l_z = (0.5f - vf) / scaleh;

  3178.             break;

  3179.         }

  3180.     }

  3181. 

  3182.     vec[0] = l_x;

  3183.     vec[1] = l_y;

  3184.     vec[2] = l_z;

  3185. 

  3186.     normalize_vector(vec);

  3187. 

  3188.     return 1;

  3189. }

  3190. 

  3191. static void multiply_matrix(float c[3][3], const float a[3][3], const float b[3][3])

  3192. {

  3193.     for (int i = 0; i < 3; i++) {

  3194.         for (int j = 0; j < 3; j++) {

  3195.             float sum = 0.f;

  3196. 

  3197.             for (int k = 0; k < 3; k++)

  3198.                 sum += a[i][k] * b[k][j];

  3199. 

  3200.             c[i][j] = sum;

  3201.         }

  3202.     }

  3203. }

  3204. 

  3205. /**

  3206.  * Calculate rotation matrix for yaw/pitch/roll angles.

  3207.  */

  3208. static inline void calculate_rotation_matrix(float yaw, float pitch, float roll,

  3209.                                              float rot_mat[3][3],

  3210.                                              const int rotation_order[3])

  3211. {

  3212.     const float yaw_rad   = yaw   * M_PI / 180.f;

  3213.     const float pitch_rad = pitch * M_PI / 180.f;

  3214.     const float roll_rad  = roll  * M_PI / 180.f;

  3215. 

  3216.     const float sin_yaw   = sinf(-yaw_rad);

  3217.     const float cos_yaw   = cosf(-yaw_rad);

  3218.     const float sin_pitch = sinf(pitch_rad);

  3219.     const float cos_pitch = cosf(pitch_rad);

  3220.     const float sin_roll  = sinf(roll_rad);

  3221.     const float cos_roll  = cosf(roll_rad);

  3222. 

  3223.     float m[3][3][3];

  3224.     float temp[3][3];

  3225. 

  3226.     m[0][0][0] =  cos_yaw;  m[0][0][1] = 0;          m[0][0][2] =  sin_yaw;

  3227.     m[0][1][0] =  0;        m[0][1][1] = 1;          m[0][1][2] =  0;

  3228.     m[0][2][0] = -sin_yaw;  m[0][2][1] = 0;          m[0][2][2] =  cos_yaw;

  3229. 

  3230.     m[1][0][0] = 1;         m[1][0][1] = 0;          m[1][0][2] =  0;

  3231.     m[1][1][0] = 0;         m[1][1][1] = cos_pitch;  m[1][1][2] = -sin_pitch;

  3232.     m[1][2][0] = 0;         m[1][2][1] = sin_pitch;  m[1][2][2] =  cos_pitch;

  3233. 

  3234.     m[2][0][0] = cos_roll;  m[2][0][1] = -sin_roll;  m[2][0][2] =  0;

  3235.     m[2][1][0] = sin_roll;  m[2][1][1] =  cos_roll;  m[2][1][2] =  0;

  3236.     m[2][2][0] = 0;         m[2][2][1] =  0;         m[2][2][2] =  1;

  3237. 

  3238.     multiply_matrix(temp, m[rotation_order[0]], m[rotation_order[1]]);

  3239.     multiply_matrix(rot_mat, temp, m[rotation_order[2]]);

  3240. }

  3241. 

  3242. /**

  3243.  * Rotate vector with given rotation matrix.

  3244.  *

  3245.  * @param rot_mat rotation matrix

  3246.  * @param vec vector

  3247.  */

  3248. static inline void rotate(const float rot_mat[3][3],

  3249.                           float *vec)

  3250. {

  3251.     const float x_tmp = vec[0] * rot_mat[0][0] + vec[1] * rot_mat[0][1] + vec[2] * rot_mat[0][2];

  3252.     const float y_tmp = vec[0] * rot_mat[1][0] + vec[1] * rot_mat[1][1] + vec[2] * rot_mat[1][2];

  3253.     const float z_tmp = vec[0] * rot_mat[2][0] + vec[1] * rot_mat[2][1] + vec[2] * rot_mat[2][2];

  3254. 

  3255.     vec[0] = x_tmp;

  3256.     vec[1] = y_tmp;

  3257.     vec[2] = z_tmp;

  3258. }

  3259. 

  3260. static inline void set_mirror_modifier(int h_flip, int v_flip, int d_flip,

  3261.                                        float *modifier)

  3262. {

  3263.     modifier[0] = h_flip ? -1.f : 1.f;

  3264.     modifier[1] = v_flip ? -1.f : 1.f;

  3265.     modifier[2] = d_flip ? -1.f : 1.f;

  3266. }

  3267. 

  3268. static inline void mirror(const float *modifier, float *vec)

  3269. {

  3270.     vec[0] *= modifier[0];

  3271.     vec[1] *= modifier[1];

  3272.     vec[2] *= modifier[2];

  3273. }

  3274. 

  3275. static int allocate_plane(V360Context *s, int sizeof_uv, int sizeof_ker, int sizeof_mask, int p)

  3276. {

  3277.     if (!s->u[p])

  3278.         s->u[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_uv);

  3279.     if (!s->v[p])

  3280.         s->v[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_uv);

  3281.     if (!s->u[p] || !s->v[p])

  3282.         return AVERROR(ENOMEM);

  3283.     if (sizeof_ker) {

  3284.         if (!s->ker[p])

  3285.             s->ker[p] = av_calloc(s->uv_linesize[p] * s->pr_height[p], sizeof_ker);

  3286.         if (!s->ker[p])

  3287.             return AVERROR(ENOMEM);

  3288.     }

  3289. 

  3290.     if (sizeof_mask && !p) {

  3291.         if (!s->mask)

  3292.             s->mask = av_calloc(s->pr_width[p] * s->pr_height[p], sizeof_mask);

  3293.         if (!s->mask)

  3294.             return AVERROR(ENOMEM);

  3295.     }

  3296. 

  3297.     return 0;

  3298. }

  3299. 

  3300. static void fov_from_dfov(int format, float d_fov, float w, float h, float *h_fov, float *v_fov)

  3301. {

  3302.     switch (format) {

  3303.     case FISHEYE:

  3304.         {

  3305.             const float d = 0.5f * hypotf(w, h);

  3306. 

  3307.             *h_fov = d / h * d_fov;

  3308.             *v_fov = d / w * d_fov;

  3309.         }

  3310.         break;

  3311.     case FLAT:

  3312.     default:

  3313.         {

  3314.             const float da = tanf(0.5 * FFMIN(d_fov, 359.f) * M_PI / 180.f);

  3315.             const float d = hypotf(w, h);

  3316. 

  3317.             *h_fov = atan2f(da * w, d) * 360.f / M_PI;

  3318.             *v_fov = atan2f(da * h, d) * 360.f / M_PI;

  3319. 

  3320.             if (*h_fov < 0.f)

  3321.                 *h_fov += 360.f;

  3322.             if (*v_fov < 0.f)

  3323.                 *v_fov += 360.f;

  3324.         }

  3325.         break;

  3326.     }

  3327. }

  3328. 

  3329. static void set_dimensions(int *outw, int *outh, int w, int h, const AVPixFmtDescriptor *desc)

  3330. {

  3331.     outw[1] = outw[2] = FF_CEIL_RSHIFT(w, desc->log2_chroma_w);

  3332.     outw[0] = outw[3] = w;

  3333.     outh[1] = outh[2] = FF_CEIL_RSHIFT(h, desc->log2_chroma_h);

  3334.     outh[0] = outh[3] = h;

  3335. }

  3336. 

  3337. // Calculate remap data

  3338. static av_always_inline int v360_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)

  3339. {

  3340.     V360Context *s = ctx->priv;

  3341. 

  3342.     for (int p = 0; p < s->nb_allocated; p++) {

  3343.         const int max_value = s->max_value;

  3344.         const int width = s->pr_width[p];

  3345.         const int uv_linesize = s->uv_linesize[p];

  3346.         const int height = s->pr_height[p];

  3347.         const int in_width = s->inplanewidth[p];

  3348.         const int in_height = s->inplaneheight[p];

  3349.         const int slice_start = (height *  jobnr     ) / nb_jobs;

  3350.         const int slice_end   = (height * (jobnr + 1)) / nb_jobs;

  3351.         float du, dv;

  3352.         float vec[3];

  3353.         XYRemap rmap;

  3354. 

  3355.         for (int j = slice_start; j < slice_end; j++) {

  3356.             for (int i = 0; i < width; i++) {

  3357.                 int16_t *u = s->u[p] + (j * uv_linesize + i) * s->elements;

  3358.                 int16_t *v = s->v[p] + (j * uv_linesize + i) * s->elements;

  3359.                 int16_t *ker = s->ker[p] + (j * uv_linesize + i) * s->elements;

  3360.                 uint8_t *mask8 = p ? NULL : s->mask + (j * s->pr_width[0] + i);

  3361.                 uint16_t *mask16 = p ? NULL : (uint16_t *)s->mask + (j * s->pr_width[0] + i);

  3362.                 int in_mask, out_mask;

  3363. 

  3364.                 if (s->out_transpose)

  3365.                     out_mask = s->out_transform(s, j, i, height, width, vec);

  3366.                 else

  3367.                     out_mask = s->out_transform(s, i, j, width, height, vec);

  3368.                 av_assert1(!isnan(vec[0]) && !isnan(vec[1]) && !isnan(vec[2]));

  3369.                 rotate(s->rot_mat, vec);

  3370.                 av_assert1(!isnan(vec[0]) && !isnan(vec[1]) && !isnan(vec[2]));

  3371.                 normalize_vector(vec);

  3372.                 mirror(s->output_mirror_modifier, vec);

  3373.                 if (s->in_transpose)

  3374.                     in_mask = s->in_transform(s, vec, in_height, in_width, rmap.v, rmap.u, &du, &dv);

  3375.                 else

  3376.                     in_mask = s->in_transform(s, vec, in_width, in_height, rmap.u, rmap.v, &du, &dv);

  3377.                 av_assert1(!isnan(du) && !isnan(dv));

  3378.                 s->calculate_kernel(du, dv, &rmap, u, v, ker);

  3379. 

  3380.                 if (!p && s->mask) {

  3381.                     if (s->mask_size == 1) {

  3382.                         mask8[0] = 255 * (out_mask & in_mask);

  3383.                     } else {

  3384.                         mask16[0] = max_value * (out_mask & in_mask);

  3385.                     }

  3386.                 }

  3387.             }

  3388.         }

  3389.     }

  3390. 

  3391.     return 0;

  3392. }

  3393. 

  3394. static int config_output(AVFilterLink *outlink)

  3395. {

  3396.     AVFilterContext *ctx = outlink->src;

  3397.     AVFilterLink *inlink = ctx->inputs[0];

  3398.     V360Context *s = ctx->priv;

  3399.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);

  3400.     const int depth = desc->comp[0].depth;

  3401.     const int sizeof_mask = s->mask_size = (depth + 7) >> 3;

  3402.     int sizeof_uv;

  3403.     int sizeof_ker;

  3404.     int err;

  3405.     int h, w;

  3406.     int in_offset_h, in_offset_w;

  3407.     int out_offset_h, out_offset_w;

  3408.     float hf, wf;

  3409.     int (*prepare_out)(AVFilterContext *ctx);

  3410.     int have_alpha;

  3411. 

  3412.     s->max_value = (1 << depth) - 1;

  3413.     s->input_mirror_modifier[0] = s->ih_flip ? -1.f : 1.f;

  3414.     s->input_mirror_modifier[1] = s->iv_flip ? -1.f : 1.f;

  3415. 

  3416.     switch (s->interp) {

  3417.     case NEAREST:

  3418.         s->calculate_kernel = nearest_kernel;

  3419.         s->remap_slice = depth <= 8 ? remap1_8bit_slice : remap1_16bit_slice;

  3420.         s->elements = 1;

  3421.         sizeof_uv = sizeof(int16_t) * s->elements;

  3422.         sizeof_ker = 0;

  3423.         break;

  3424.     case BILINEAR:

  3425.         s->calculate_kernel = bilinear_kernel;

  3426.         s->remap_slice = depth <= 8 ? remap2_8bit_slice : remap2_16bit_slice;

  3427.         s->elements = 2 * 2;

  3428.         sizeof_uv = sizeof(int16_t) * s->elements;

  3429.         sizeof_ker = sizeof(int16_t) * s->elements;

  3430.         break;

  3431.     case BICUBIC:

  3432.         s->calculate_kernel = bicubic_kernel;

  3433.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3434.         s->elements = 4 * 4;

  3435.         sizeof_uv = sizeof(int16_t) * s->elements;

  3436.         sizeof_ker = sizeof(int16_t) * s->elements;

  3437.         break;

  3438.     case LANCZOS:

  3439.         s->calculate_kernel = lanczos_kernel;

  3440.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3441.         s->elements = 4 * 4;

  3442.         sizeof_uv = sizeof(int16_t) * s->elements;

  3443.         sizeof_ker = sizeof(int16_t) * s->elements;

  3444.         break;

  3445.     case SPLINE16:

  3446.         s->calculate_kernel = spline16_kernel;

  3447.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3448.         s->elements = 4 * 4;

  3449.         sizeof_uv = sizeof(int16_t) * s->elements;

  3450.         sizeof_ker = sizeof(int16_t) * s->elements;

  3451.         break;

  3452.     case GAUSSIAN:

  3453.         s->calculate_kernel = gaussian_kernel;

  3454.         s->remap_slice = depth <= 8 ? remap4_8bit_slice : remap4_16bit_slice;

  3455.         s->elements = 4 * 4;

  3456.         sizeof_uv = sizeof(int16_t) * s->elements;

  3457.         sizeof_ker = sizeof(int16_t) * s->elements;

  3458.         break;

  3459.     default:

  3460.         av_assert0(0);

  3461.     }

  3462. 

  3463.     ff_v360_init(s, depth);

  3464. 

  3465.     for (int order = 0; order < NB_RORDERS; order++) {

  3466.         const char c = s->rorder[order];

  3467.         int rorder;

  3468. 

  3469.         if (c == '\0') {

  3470.             av_log(ctx, AV_LOG_WARNING,

  3471.                    "Incomplete rorder option. Direction for all 3 rotation orders should be specified. Switching to default rorder.\n");

  3472.             s->rotation_order[0] = YAW;

  3473.             s->rotation_order[1] = PITCH;

  3474.             s->rotation_order[2] = ROLL;

  3475.             break;

  3476.         }

  3477. 

  3478.         rorder = get_rorder(c);

  3479.         if (rorder == -1) {

  3480.             av_log(ctx, AV_LOG_WARNING,

  3481.                    "Incorrect rotation order symbol '%c' in rorder option. Switching to default rorder.\n", c);

  3482.             s->rotation_order[0] = YAW;

  3483.             s->rotation_order[1] = PITCH;

  3484.             s->rotation_order[2] = ROLL;

  3485.             break;

  3486.         }

  3487. 

  3488.         s->rotation_order[order] = rorder;

  3489.     }

  3490. 

  3491.     switch (s->in_stereo) {

  3492.     case STEREO_2D:

  3493.         w = inlink->w;

  3494.         h = inlink->h;

  3495.         in_offset_w = in_offset_h = 0;

  3496.         break;

  3497.     case STEREO_SBS:

  3498.         w = inlink->w / 2;

  3499.         h = inlink->h;

  3500.         in_offset_w = w;

  3501.         in_offset_h = 0;

  3502.         break;

  3503.     case STEREO_TB:

  3504.         w = inlink->w;

  3505.         h = inlink->h / 2;

  3506.         in_offset_w = 0;

  3507.         in_offset_h = h;

  3508.         break;

  3509.     default:

  3510.         av_assert0(0);

  3511.     }

  3512. 

  3513.     set_dimensions(s->inplanewidth, s->inplaneheight, w, h, desc);

  3514.     set_dimensions(s->in_offset_w, s->in_offset_h, in_offset_w, in_offset_h, desc);

  3515. 

  3516.     s->in_width = s->inplanewidth[0];

  3517.     s->in_height = s->inplaneheight[0];

  3518. 

  3519.     if (s->id_fov > 0.f)

  3520.         fov_from_dfov(s->in, s->id_fov, w, h, &s->ih_fov, &s->iv_fov);

  3521. 

  3522.     if (s->in_transpose)

  3523.         FFSWAP(int, s->in_width, s->in_height);

  3524. 

  3525.     switch (s->in) {

  3526.     case EQUIRECTANGULAR:

  3527.         s->in_transform = xyz_to_equirect;

  3528.         err = 0;

  3529.         wf = w;

  3530.         hf = h;

  3531.         break;

  3532.     case CUBEMAP_3_2:

  3533.         s->in_transform = xyz_to_cube3x2;

  3534.         err = prepare_cube_in(ctx);

  3535.         wf = w / 3.f * 4.f;

  3536.         hf = h;

  3537.         break;

  3538.     case CUBEMAP_1_6:

  3539.         s->in_transform = xyz_to_cube1x6;

  3540.         err = prepare_cube_in(ctx);

  3541.         wf = w * 4.f;

  3542.         hf = h / 3.f;

  3543.         break;

  3544.     case CUBEMAP_6_1:

  3545.         s->in_transform = xyz_to_cube6x1;

  3546.         err = prepare_cube_in(ctx);

  3547.         wf = w / 3.f * 2.f;

  3548.         hf = h * 2.f;

  3549.         break;

  3550.     case EQUIANGULAR:

  3551.         s->in_transform = xyz_to_eac;

  3552.         err = prepare_eac_in(ctx);

  3553.         wf = w;

  3554.         hf = h / 9.f * 8.f;

  3555.         break;

  3556.     case FLAT:

  3557.         s->in_transform = xyz_to_flat;

  3558.         err = prepare_flat_in(ctx);

  3559.         wf = w;

  3560.         hf = h;

  3561.         break;

  3562.     case PERSPECTIVE:

  3563.     case PANNINI:

  3564.         av_log(ctx, AV_LOG_ERROR, "Supplied format is not accepted as input.\n");

  3565.         return AVERROR(EINVAL);

  3566.     case DUAL_FISHEYE:

  3567.         s->in_transform = xyz_to_dfisheye;

  3568.         err = 0;

  3569.         wf = w;

  3570.         hf = h;

  3571.         break;

  3572.     case BARREL:

  3573.         s->in_transform = xyz_to_barrel;

  3574.         err = 0;

  3575.         wf = w / 5.f * 4.f;

  3576.         hf = h;

  3577.         break;

  3578.     case STEREOGRAPHIC:

  3579.         s->in_transform = xyz_to_stereographic;

  3580.         err = prepare_stereographic_in(ctx);

  3581.         wf = w;

  3582.         hf = h / 2.f;

  3583.         break;

  3584.     case MERCATOR:

  3585.         s->in_transform = xyz_to_mercator;

  3586.         err = 0;

  3587.         wf = w;

  3588.         hf = h / 2.f;

  3589.         break;

  3590.     case BALL:

  3591.         s->in_transform = xyz_to_ball;

  3592.         err = 0;

  3593.         wf = w;

  3594.         hf = h / 2.f;

  3595.         break;

  3596.     case HAMMER:

  3597.         s->in_transform = xyz_to_hammer;

  3598.         err = 0;

  3599.         wf = w;

  3600.         hf = h;

  3601.         break;

  3602.     case SINUSOIDAL:

  3603.         s->in_transform = xyz_to_sinusoidal;

  3604.         err = 0;

  3605.         wf = w;

  3606.         hf = h;

  3607.         break;

  3608.     case FISHEYE:

  3609.         s->in_transform = xyz_to_fisheye;

  3610.         err = prepare_fisheye_in(ctx);

  3611.         wf = w * 2;

  3612.         hf = h;

  3613.         break;

  3614.     case CYLINDRICAL:

  3615.         s->in_transform = xyz_to_cylindrical;

  3616.         err = prepare_cylindrical_in(ctx);

  3617.         wf = w;

  3618.         hf = h * 2.f;

  3619.         break;

  3620.     case TETRAHEDRON:

  3621.         s->in_transform = xyz_to_tetrahedron;

  3622.         err = 0;

  3623.         wf = w;

  3624.         hf = h;

  3625.         break;

  3626.     case BARREL_SPLIT:

  3627.         s->in_transform = xyz_to_barrelsplit;

  3628.         err = 0;

  3629.         wf = w * 4.f / 3.f;

  3630.         hf = h;

  3631.         break;

  3632.     default:

  3633.         av_log(ctx, AV_LOG_ERROR, "Specified input format is not handled.\n");

  3634.         return AVERROR_BUG;

  3635.     }

  3636. 

  3637.     if (err != 0) {

  3638.         return err;

  3639.     }

  3640. 

  3641.     switch (s->out) {

  3642.     case EQUIRECTANGULAR:

  3643.         s->out_transform = equirect_to_xyz;

  3644.         prepare_out = NULL;

  3645.         w = lrintf(wf);

  3646.         h = lrintf(hf);

  3647.         break;

  3648.     case CUBEMAP_3_2:

  3649.         s->out_transform = cube3x2_to_xyz;

  3650.         prepare_out = prepare_cube_out;

  3651.         w = lrintf(wf / 4.f * 3.f);

  3652.         h = lrintf(hf);

  3653.         break;

  3654.     case CUBEMAP_1_6:

  3655.         s->out_transform = cube1x6_to_xyz;

  3656.         prepare_out = prepare_cube_out;

  3657.         w = lrintf(wf / 4.f);

  3658.         h = lrintf(hf * 3.f);

  3659.         break;

  3660.     case CUBEMAP_6_1:

  3661.         s->out_transform = cube6x1_to_xyz;

  3662.         prepare_out = prepare_cube_out;

  3663.         w = lrintf(wf / 2.f * 3.f);

  3664.         h = lrintf(hf / 2.f);

  3665.         break;

  3666.     case EQUIANGULAR:

  3667.         s->out_transform = eac_to_xyz;

  3668.         prepare_out = prepare_eac_out;

  3669.         w = lrintf(wf);

  3670.         h = lrintf(hf / 8.f * 9.f);

  3671.         break;

  3672.     case FLAT:

  3673.         s->out_transform = flat_to_xyz;

  3674.         prepare_out = prepare_flat_out;

  3675.         w = lrintf(wf);

  3676.         h = lrintf(hf);

  3677.         break;

  3678.     case DUAL_FISHEYE:

  3679.         s->out_transform = dfisheye_to_xyz;

  3680.         prepare_out = NULL;

  3681.         w = lrintf(wf);

  3682.         h = lrintf(hf);

  3683.         break;

  3684.     case BARREL:

  3685.         s->out_transform = barrel_to_xyz;

  3686.         prepare_out = NULL;

  3687.         w = lrintf(wf / 4.f * 5.f);

  3688.         h = lrintf(hf);

  3689.         break;

  3690.     case STEREOGRAPHIC:

  3691.         s->out_transform = stereographic_to_xyz;

  3692.         prepare_out = prepare_stereographic_out;

  3693.         w = lrintf(wf);

  3694.         h = lrintf(hf * 2.f);

  3695.         break;

  3696.     case MERCATOR:

  3697.         s->out_transform = mercator_to_xyz;

  3698.         prepare_out = NULL;

  3699.         w = lrintf(wf);

  3700.         h = lrintf(hf * 2.f);

  3701.         break;

  3702.     case BALL:

  3703.         s->out_transform = ball_to_xyz;

  3704.         prepare_out = NULL;

  3705.         w = lrintf(wf);

  3706.         h = lrintf(hf * 2.f);

  3707.         break;

  3708.     case HAMMER:

  3709.         s->out_transform = hammer_to_xyz;

  3710.         prepare_out = NULL;

  3711.         w = lrintf(wf);

  3712.         h = lrintf(hf);

  3713.         break;

  3714.     case SINUSOIDAL:

  3715.         s->out_transform = sinusoidal_to_xyz;

  3716.         prepare_out = NULL;

  3717.         w = lrintf(wf);

  3718.         h = lrintf(hf);

  3719.         break;

  3720.     case FISHEYE:

  3721.         s->out_transform = fisheye_to_xyz;

  3722.         prepare_out = prepare_fisheye_out;

  3723.         w = lrintf(wf * 0.5f);

  3724.         h = lrintf(hf);

  3725.         break;

  3726.     case PANNINI:

  3727.         s->out_transform = pannini_to_xyz;

  3728.         prepare_out = NULL;

  3729.         w = lrintf(wf);

  3730.         h = lrintf(hf);

  3731.         break;

  3732.     case CYLINDRICAL:

  3733.         s->out_transform = cylindrical_to_xyz;

  3734.         prepare_out = prepare_cylindrical_out;

  3735.         w = lrintf(wf);

  3736.         h = lrintf(hf * 0.5f);

  3737.         break;

  3738.     case PERSPECTIVE:

  3739.         s->out_transform = perspective_to_xyz;

  3740.         prepare_out = NULL;

  3741.         w = lrintf(wf / 2.f);

  3742.         h = lrintf(hf);

  3743.         break;

  3744.     case TETRAHEDRON:

  3745.         s->out_transform = tetrahedron_to_xyz;

  3746.         prepare_out = NULL;

  3747.         w = lrintf(wf);

  3748.         h = lrintf(hf);

  3749.         break;

  3750.     case BARREL_SPLIT:

  3751.         s->out_transform = barrelsplit_to_xyz;

  3752.         prepare_out = NULL;

  3753.         w = lrintf(wf / 4.f * 3.f);

  3754.         h = lrintf(hf);

  3755.         break;

  3756.     default:

  3757.         av_log(ctx, AV_LOG_ERROR, "Specified output format is not handled.\n");

  3758.         return AVERROR_BUG;

  3759.     }

  3760. 

  3761.     // Override resolution with user values if specified

  3762.     if (s->width > 0 && s->height > 0) {

  3763.         w = s->width;

  3764.         h = s->height;

  3765.     } else if (s->width > 0 || s->height > 0) {

  3766.         av_log(ctx, AV_LOG_ERROR, "Both width and height values should be specified.\n");

  3767.         return AVERROR(EINVAL);

  3768.     } else {

  3769.         if (s->out_transpose)

  3770.             FFSWAP(int, w, h);

  3771. 

  3772.         if (s->in_transpose)

  3773.             FFSWAP(int, w, h);

  3774.     }

  3775. 

  3776.     s->width  = w;

  3777.     s->height = h;

  3778. 

  3779.     if (s->d_fov > 0.f)

  3780.         fov_from_dfov(s->out, s->d_fov, w, h, &s->h_fov, &s->v_fov);

  3781. 

  3782.     if (prepare_out) {

  3783.         err = prepare_out(ctx);

  3784.         if (err != 0)

  3785.             return err;

  3786.     }

  3787. 

  3788.     set_dimensions(s->pr_width, s->pr_height, w, h, desc);

  3789. 

  3790.     s->out_width = s->pr_width[0];

  3791.     s->out_height = s->pr_height[0];

  3792. 

  3793.     if (s->out_transpose)

  3794.         FFSWAP(int, s->out_width, s->out_height);

  3795. 

  3796.     switch (s->out_stereo) {

  3797.     case STEREO_2D:

  3798.         out_offset_w = out_offset_h = 0;

  3799.         break;

  3800.     case STEREO_SBS:

  3801.         out_offset_w = w;

  3802.         out_offset_h = 0;

  3803.         w *= 2;

  3804.         break;

  3805.     case STEREO_TB:

  3806.         out_offset_w = 0;

  3807.         out_offset_h = h;

  3808.         h *= 2;

  3809.         break;

  3810.     default:

  3811.         av_assert0(0);

  3812.     }

  3813. 

  3814.     set_dimensions(s->out_offset_w, s->out_offset_h, out_offset_w, out_offset_h, desc);

  3815.     set_dimensions(s->planewidth, s->planeheight, w, h, desc);

  3816. 

  3817.     for (int i = 0; i < 4; i++)

  3818.         s->uv_linesize[i] = FFALIGN(s->pr_width[i], 8);

  3819. 

  3820.     outlink->h = h;

  3821.     outlink->w = w;

  3822. 

  3823.     s->nb_planes = av_pix_fmt_count_planes(inlink->format);

  3824.     have_alpha   = !!(desc->flags & AV_PIX_FMT_FLAG_ALPHA);

  3825. 

  3826.     if (desc->log2_chroma_h == desc->log2_chroma_w && desc->log2_chroma_h == 0) {

  3827.         s->nb_allocated = 1;

  3828.         s->map[0] = s->map[1] = s->map[2] = s->map[3] = 0;

  3829.     } else {

  3830.         s->nb_allocated = 2;

  3831.         s->map[0] = s->map[3] = 0;

  3832.         s->map[1] = s->map[2] = 1;

  3833.     }

  3834. 

  3835.     for (int i = 0; i < s->nb_allocated; i++)

  3836.         allocate_plane(s, sizeof_uv, sizeof_ker, sizeof_mask * have_alpha * s->alpha, i);

  3837. 

  3838.     calculate_rotation_matrix(s->yaw, s->pitch, s->roll, s->rot_mat, s->rotation_order);

  3839.     set_mirror_modifier(s->h_flip, s->v_flip, s->d_flip, s->output_mirror_modifier);

  3840. 

  3841.     ctx->internal->execute(ctx, v360_slice, NULL, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));

  3842. 

  3843.     return 0;

  3844. }

  3845. 

  3846. static int filter_frame(AVFilterLink *inlink, AVFrame *in)

  3847. {

  3848.     AVFilterContext *ctx = inlink->dst;

  3849.     AVFilterLink *outlink = ctx->outputs[0];

  3850.     V360Context *s = ctx->priv;

  3851.     AVFrame *out;

  3852.     ThreadData td;

  3853. 

  3854.     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);

  3855.     if (!out) {

  3856.         av_frame_free(&in);

  3857.         return AVERROR(ENOMEM);

  3858.     }

  3859.     av_frame_copy_props(out, in);

  3860. 

  3861.     td.in = in;

  3862.     td.out = out;

  3863. 

  3864.     ctx->internal->execute(ctx, s->remap_slice, &td, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));

  3865. 

  3866.     av_frame_free(&in);

  3867.     return ff_filter_frame(outlink, out);

  3868. }

  3869. 

  3870. static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,

  3871.                            char *res, int res_len, int flags)

  3872. {

  3873.     int ret;

  3874. 

  3875.     ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);

  3876.     if (ret < 0)

  3877.         return ret;

  3878. 

  3879.     return config_output(ctx->outputs[0]);

  3880. }

  3881. 

  3882. static av_cold void uninit(AVFilterContext *ctx)

  3883. {

  3884.     V360Context *s = ctx->priv;

  3885. 

  3886.     for (int p = 0; p < s->nb_allocated; p++) {

  3887.         av_freep(&s->u[p]);

  3888.         av_freep(&s->v[p]);

  3889.         av_freep(&s->ker[p]);

  3890.     }

  3891.     av_freep(&s->mask);

  3892. }

  3893. 

  3894. static const AVFilterPad inputs[] = {

  3895.     {

  3896.         .name         = "default",

  3897.         .type         = AVMEDIA_TYPE_VIDEO,

  3898.         .filter_frame = filter_frame,

  3899.     },

  3900.     { NULL }

  3901. };

  3902. 

  3903. static const AVFilterPad outputs[] = {

  3904.     {

  3905.         .name         = "default",

  3906.         .type         = AVMEDIA_TYPE_VIDEO,

  3907.         .config_props = config_output,

  3908.     },

  3909.     { NULL }

  3910. };

  3911. 

  3912. AVFilter ff_vf_v360 = {

  3913.     .name          = "v360",

  3914.     .description   = NULL_IF_CONFIG_SMALL("Convert 360 projection of video."),

  3915.     .priv_size     = sizeof(V360Context),

  3916.     .uninit        = uninit,

  3917.     .query_formats = query_formats,

  3918.     .inputs        = inputs,

  3919.     .outputs       = outputs,

  3920.     .priv_class    = &v360_class,

  3921.     .flags         = AVFILTER_FLAG_SLICE_THREADS,

  3922.     .process_command = process_command,

  3923. };