falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
52966 Commits
32 Branches
1.4GB
Tree: 496f2df908
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '496f2df908'
${ noResults }
FFmpeg/libavcodec/indeo3.c

1141 lines
41KB
Raw Blame History 

  1. /*

  2.  * Indeo Video v3 compatible decoder

  3.  * Copyright (c) 2009 - 2011 Maxim Poliakovski

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

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

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

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

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

  11.  *

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

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

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

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

  20.  */

  21. 

  22. /**

  23.  * @file

  24.  * This is a decoder for Intel Indeo Video v3.

  25.  * It is based on vector quantization, run-length coding and motion compensation.

  26.  * Known container formats: .avi and .mov

  27.  * Known FOURCCs: 'IV31', 'IV32'

  28.  *

  29.  * @see http://wiki.multimedia.cx/index.php?title=Indeo_3

  30.  */

  31. 

  32. #include "libavutil/imgutils.h"

  33. #include "libavutil/intreadwrite.h"

  34. #include "avcodec.h"

  35. #include "copy_block.h"

  36. #include "bytestream.h"

  37. #include "get_bits.h"

  38. #include "hpeldsp.h"

  39. #include "internal.h"

  40. 

  41. #include "indeo3data.h"

  42. 

  43. /* RLE opcodes. */

  44. enum {

  45.     RLE_ESC_F9    = 249, ///< same as RLE_ESC_FA + do the same with next block

  46.     RLE_ESC_FA    = 250, ///< INTRA: skip block, INTER: copy data from reference

  47.     RLE_ESC_FB    = 251, ///< apply null delta to N blocks / skip N blocks

  48.     RLE_ESC_FC    = 252, ///< same as RLE_ESC_FD + do the same with next block

  49.     RLE_ESC_FD    = 253, ///< apply null delta to all remaining lines of this block

  50.     RLE_ESC_FE    = 254, ///< apply null delta to all lines up to the 3rd line

  51.     RLE_ESC_FF    = 255  ///< apply null delta to all lines up to the 2nd line

  52. };

  53. 

  54. 

  55. /* Some constants for parsing frame bitstream flags. */

  56. #define BS_8BIT_PEL     (1 << 1) ///< 8bit pixel bitdepth indicator

  57. #define BS_KEYFRAME     (1 << 2) ///< intra frame indicator

  58. #define BS_MV_Y_HALF    (1 << 4) ///< vertical mv halfpel resolution indicator

  59. #define BS_MV_X_HALF    (1 << 5) ///< horizontal mv halfpel resolution indicator

  60. #define BS_NONREF       (1 << 8) ///< nonref (discardable) frame indicator

  61. #define BS_BUFFER        9       ///< indicates which of two frame buffers should be used

  62. 

  63. 

  64. typedef struct Plane {

  65.     uint8_t         *buffers[2];

  66.     uint8_t         *pixels[2]; ///< pointer to the actual pixel data of the buffers above

  67.     uint32_t        width;

  68.     uint32_t        height;

  69.     uint32_t        pitch;

  70. } Plane;

  71. 

  72. #define CELL_STACK_MAX  20

  73. 

  74. typedef struct Cell {

  75.     int16_t         xpos;       ///< cell coordinates in 4x4 blocks

  76.     int16_t         ypos;

  77.     int16_t         width;      ///< cell width  in 4x4 blocks

  78.     int16_t         height;     ///< cell height in 4x4 blocks

  79.     uint8_t         tree;       ///< tree id: 0- MC tree, 1 - VQ tree

  80.     const int8_t    *mv_ptr;    ///< ptr to the motion vector if any

  81. } Cell;

  82. 

  83. typedef struct Indeo3DecodeContext {

  84.     AVCodecContext *avctx;

  85.     HpelDSPContext  hdsp;

  86. 

  87.     GetBitContext   gb;

  88.     int             need_resync;

  89.     int             skip_bits;

  90.     const uint8_t   *next_cell_data;

  91.     const uint8_t   *last_byte;

  92.     const int8_t    *mc_vectors;

  93.     unsigned        num_vectors;    ///< number of motion vectors in mc_vectors

  94. 

  95.     int16_t         width, height;

  96.     uint32_t        frame_num;      ///< current frame number (zero-based)

  97.     uint32_t        data_size;      ///< size of the frame data in bytes

  98.     uint16_t        frame_flags;    ///< frame properties

  99.     uint8_t         cb_offset;      ///< needed for selecting VQ tables

  100.     uint8_t         buf_sel;        ///< active frame buffer: 0 - primary, 1 -secondary

  101.     const uint8_t   *y_data_ptr;

  102.     const uint8_t   *v_data_ptr;

  103.     const uint8_t   *u_data_ptr;

  104.     int32_t         y_data_size;

  105.     int32_t         v_data_size;

  106.     int32_t         u_data_size;

  107.     const uint8_t   *alt_quant;     ///< secondary VQ table set for the modes 1 and 4

  108.     Plane           planes[3];

  109. } Indeo3DecodeContext;

  110. 

  111. 

  112. static uint8_t requant_tab[8][128];

  113. 

  114. /*

  115.  *  Build the static requantization table.

  116.  *  This table is used to remap pixel values according to a specific

  117.  *  quant index and thus avoid overflows while adding deltas.

  118.  */

  119. static av_cold void build_requant_tab(void)

  120. {

  121.     static int8_t offsets[8] = { 1, 1, 2, -3, -3, 3, 4, 4 };

  122.     static int8_t deltas [8] = { 0, 1, 0,  4,  4, 1, 0, 1 };

  123. 

  124.     int i, j, step;

  125. 

  126.     for (i = 0; i < 8; i++) {

  127.         step = i + 2;

  128.         for (j = 0; j < 128; j++)

  129.                 requant_tab[i][j] = (j + offsets[i]) / step * step + deltas[i];

  130.     }

  131. 

  132.     /* some last elements calculated above will have values >= 128 */

  133.     /* pixel values shall never exceed 127 so set them to non-overflowing values */

  134.     /* according with the quantization step of the respective section */

  135.     requant_tab[0][127] = 126;

  136.     requant_tab[1][119] = 118;

  137.     requant_tab[1][120] = 118;

  138.     requant_tab[2][126] = 124;

  139.     requant_tab[2][127] = 124;

  140.     requant_tab[6][124] = 120;

  141.     requant_tab[6][125] = 120;

  142.     requant_tab[6][126] = 120;

  143.     requant_tab[6][127] = 120;

  144. 

  145.     /* Patch for compatibility with the Intel's binary decoders */

  146.     requant_tab[1][7] = 10;

  147.     requant_tab[4][8] = 10;

  148. }

  149. 

  150. 

  151. static av_cold int allocate_frame_buffers(Indeo3DecodeContext *ctx,

  152.                                           AVCodecContext *avctx, int luma_width, int luma_height)

  153. {

  154.     int p, chroma_width, chroma_height;

  155.     int luma_pitch, chroma_pitch, luma_size, chroma_size;

  156. 

  157.     if (luma_width  < 16 || luma_width  > 640 ||

  158.         luma_height < 16 || luma_height > 480 ||

  159.         luma_width  &  3 || luma_height &   3) {

  160.         av_log(avctx, AV_LOG_ERROR, "Invalid picture dimensions: %d x %d!\n",

  161.                luma_width, luma_height);

  162.         return AVERROR_INVALIDDATA;

  163.     }

  164. 

  165.     ctx->width  = luma_width ;

  166.     ctx->height = luma_height;

  167. 

  168.     chroma_width  = FFALIGN(luma_width  >> 2, 4);

  169.     chroma_height = FFALIGN(luma_height >> 2, 4);

  170. 

  171.     luma_pitch   = FFALIGN(luma_width,   16);

  172.     chroma_pitch = FFALIGN(chroma_width, 16);

  173. 

  174.     /* Calculate size of the luminance plane.  */

  175.     /* Add one line more for INTRA prediction. */

  176.     luma_size = luma_pitch * (luma_height + 1);

  177. 

  178.     /* Calculate size of a chrominance planes. */

  179.     /* Add one line more for INTRA prediction. */

  180.     chroma_size = chroma_pitch * (chroma_height + 1);

  181. 

  182.     /* allocate frame buffers */

  183.     for (p = 0; p < 3; p++) {

  184.         ctx->planes[p].pitch  = !p ? luma_pitch  : chroma_pitch;

  185.         ctx->planes[p].width  = !p ? luma_width  : chroma_width;

  186.         ctx->planes[p].height = !p ? luma_height : chroma_height;

  187. 

  188.         ctx->planes[p].buffers[0] = av_malloc(!p ? luma_size : chroma_size);

  189.         ctx->planes[p].buffers[1] = av_malloc(!p ? luma_size : chroma_size);

  190. 

  191.         /* fill the INTRA prediction lines with the middle pixel value = 64 */

  192.         memset(ctx->planes[p].buffers[0], 0x40, ctx->planes[p].pitch);

  193.         memset(ctx->planes[p].buffers[1], 0x40, ctx->planes[p].pitch);

  194. 

  195.         /* set buffer pointers = buf_ptr + pitch and thus skip the INTRA prediction line */

  196.         ctx->planes[p].pixels[0] = ctx->planes[p].buffers[0] + ctx->planes[p].pitch;

  197.         ctx->planes[p].pixels[1] = ctx->planes[p].buffers[1] + ctx->planes[p].pitch;

  198.         memset(ctx->planes[p].pixels[0], 0, ctx->planes[p].pitch * ctx->planes[p].height);

  199.         memset(ctx->planes[p].pixels[1], 0, ctx->planes[p].pitch * ctx->planes[p].height);

  200.     }

  201. 

  202.     return 0;

  203. }

  204. 

  205. 

  206. static av_cold void free_frame_buffers(Indeo3DecodeContext *ctx)

  207. {

  208.     int p;

  209. 

  210.     ctx->width=

  211.     ctx->height= 0;

  212. 

  213.     for (p = 0; p < 3; p++) {

  214.         av_freep(&ctx->planes[p].buffers[0]);

  215.         av_freep(&ctx->planes[p].buffers[1]);

  216.         ctx->planes[p].pixels[0] = ctx->planes[p].pixels[1] = 0;

  217.     }

  218. }

  219. 

  220. 

  221. /**

  222.  *  Copy pixels of the cell(x + mv_x, y + mv_y) from the previous frame into

  223.  *  the cell(x, y) in the current frame.

  224.  *

  225.  *  @param ctx      pointer to the decoder context

  226.  *  @param plane    pointer to the plane descriptor

  227.  *  @param cell     pointer to the cell  descriptor

  228.  */

  229. static int copy_cell(Indeo3DecodeContext *ctx, Plane *plane, Cell *cell)

  230. {

  231.     int     h, w, mv_x, mv_y, offset, offset_dst;

  232.     uint8_t *src, *dst;

  233. 

  234.     /* setup output and reference pointers */

  235.     offset_dst  = (cell->ypos << 2) * plane->pitch + (cell->xpos << 2);

  236.     dst         = plane->pixels[ctx->buf_sel] + offset_dst;

  237.     if(cell->mv_ptr){

  238.     mv_y        = cell->mv_ptr[0];

  239.     mv_x        = cell->mv_ptr[1];

  240.     }else

  241.         mv_x= mv_y= 0;

  242. 

  243.     /* -1 because there is an extra line on top for prediction */

  244.     if ((cell->ypos << 2) + mv_y < -1 || (cell->xpos << 2) + mv_x < 0 ||

  245.         ((cell->ypos + cell->height) << 2) + mv_y > plane->height     ||

  246.         ((cell->xpos + cell->width)  << 2) + mv_x > plane->width) {

  247.         av_log(ctx->avctx, AV_LOG_ERROR,

  248.                "Motion vectors point out of the frame.\n");

  249.         return AVERROR_INVALIDDATA;

  250.     }

  251. 

  252.     offset      = offset_dst + mv_y * plane->pitch + mv_x;

  253.     src         = plane->pixels[ctx->buf_sel ^ 1] + offset;

  254. 

  255.     h = cell->height << 2;

  256. 

  257.     for (w = cell->width; w > 0;) {

  258.         /* copy using 16xH blocks */

  259.         if (!((cell->xpos << 2) & 15) && w >= 4) {

  260.             for (; w >= 4; src += 16, dst += 16, w -= 4)

  261.                 ctx->hdsp.put_pixels_tab[0][0](dst, src, plane->pitch, h);

  262.         }

  263. 

  264.         /* copy using 8xH blocks */

  265.         if (!((cell->xpos << 2) & 7) && w >= 2) {

  266.             ctx->hdsp.put_pixels_tab[1][0](dst, src, plane->pitch, h);

  267.             w -= 2;

  268.             src += 8;

  269.             dst += 8;

  270.         } else if (w >= 1) {

  271.             ctx->hdsp.put_pixels_tab[2][0](dst, src, plane->pitch, h);

  272.             w--;

  273.             src += 4;

  274.             dst += 4;

  275.         }

  276.     }

  277. 

  278.     return 0;

  279. }

  280. 

  281. 

  282. /* Average 4/8 pixels at once without rounding using SWAR */

  283. #define AVG_32(dst, src, ref) \

  284.     AV_WN32A(dst, ((AV_RN32(src) + AV_RN32(ref)) >> 1) & 0x7F7F7F7FUL)

  285. 

  286. #define AVG_64(dst, src, ref) \

  287.     AV_WN64A(dst, ((AV_RN64(src) + AV_RN64(ref)) >> 1) & 0x7F7F7F7F7F7F7F7FULL)

  288. 

  289. 

  290. /*

  291.  *  Replicate each even pixel as follows:

  292.  *  ABCDEFGH -> AACCEEGG

  293.  */

  294. static inline uint64_t replicate64(uint64_t a) {

  295. #if HAVE_BIGENDIAN

  296.     a &= 0xFF00FF00FF00FF00ULL;

  297.     a |= a >> 8;

  298. #else

  299.     a &= 0x00FF00FF00FF00FFULL;

  300.     a |= a << 8;

  301. #endif

  302.     return a;

  303. }

  304. 

  305. static inline uint32_t replicate32(uint32_t a) {

  306. #if HAVE_BIGENDIAN

  307.     a &= 0xFF00FF00UL;

  308.     a |= a >> 8;

  309. #else

  310.     a &= 0x00FF00FFUL;

  311.     a |= a << 8;

  312. #endif

  313.     return a;

  314. }

  315. 

  316. 

  317. /* Fill n lines with 64bit pixel value pix */

  318. static inline void fill_64(uint8_t *dst, const uint64_t pix, int32_t n,

  319.                            int32_t row_offset)

  320. {

  321.     for (; n > 0; dst += row_offset, n--)

  322.         AV_WN64A(dst, pix);

  323. }

  324. 

  325. 

  326. /* Error codes for cell decoding. */

  327. enum {

  328.     IV3_NOERR       = 0,

  329.     IV3_BAD_RLE     = 1,

  330.     IV3_BAD_DATA    = 2,

  331.     IV3_BAD_COUNTER = 3,

  332.     IV3_UNSUPPORTED = 4,

  333.     IV3_OUT_OF_DATA = 5

  334. };

  335. 

  336. 

  337. #define BUFFER_PRECHECK \

  338. if (*data_ptr >= last_ptr) \

  339.     return IV3_OUT_OF_DATA; \

  340. 

  341. #define RLE_BLOCK_COPY \

  342.     if (cell->mv_ptr || !skip_flag) \

  343.         copy_block4(dst, ref, row_offset, row_offset, 4 << v_zoom)

  344. 

  345. #define RLE_BLOCK_COPY_8 \

  346.     pix64 = AV_RN64(ref);\

  347.     if (is_first_row) {/* special prediction case: top line of a cell */\

  348.         pix64 = replicate64(pix64);\

  349.         fill_64(dst + row_offset, pix64, 7, row_offset);\

  350.         AVG_64(dst, ref, dst + row_offset);\

  351.     } else \

  352.         fill_64(dst, pix64, 8, row_offset)

  353. 

  354. #define RLE_LINES_COPY \

  355.     copy_block4(dst, ref, row_offset, row_offset, num_lines << v_zoom)

  356. 

  357. #define RLE_LINES_COPY_M10 \

  358.     pix64 = AV_RN64(ref);\

  359.     if (is_top_of_cell) {\

  360.         pix64 = replicate64(pix64);\

  361.         fill_64(dst + row_offset, pix64, (num_lines << 1) - 1, row_offset);\

  362.         AVG_64(dst, ref, dst + row_offset);\

  363.     } else \

  364.         fill_64(dst, pix64, num_lines << 1, row_offset)

  365. 

  366. #define APPLY_DELTA_4 \

  367.     AV_WN16A(dst + line_offset    ,\

  368.              (AV_RN16(ref    ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  369.     AV_WN16A(dst + line_offset + 2,\

  370.              (AV_RN16(ref + 2) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  371.     if (mode >= 3) {\

  372.         if (is_top_of_cell && !cell->ypos) {\

  373.             AV_COPY32U(dst, dst + row_offset);\

  374.         } else {\

  375.             AVG_32(dst, ref, dst + row_offset);\

  376.         }\

  377.     }

  378. 

  379. #define APPLY_DELTA_8 \

  380.     /* apply two 32-bit VQ deltas to next even line */\

  381.     if (is_top_of_cell) { \

  382.         AV_WN32A(dst + row_offset    , \

  383.                  (replicate32(AV_RN32(ref    )) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  384.         AV_WN32A(dst + row_offset + 4, \

  385.                  (replicate32(AV_RN32(ref + 4)) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  386.     } else { \

  387.         AV_WN32A(dst + row_offset    , \

  388.                  (AV_RN32(ref    ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  389.         AV_WN32A(dst + row_offset + 4, \

  390.                  (AV_RN32(ref + 4) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  391.     } \

  392.     /* odd lines are not coded but rather interpolated/replicated */\

  393.     /* first line of the cell on the top of image? - replicate */\

  394.     /* otherwise - interpolate */\

  395.     if (is_top_of_cell && !cell->ypos) {\

  396.         AV_COPY64U(dst, dst + row_offset);\

  397.     } else \

  398.         AVG_64(dst, ref, dst + row_offset);

  399. 

  400. 

  401. #define APPLY_DELTA_1011_INTER \

  402.     if (mode == 10) { \

  403.         AV_WN32A(dst                 , \

  404.                  (AV_RN32(dst                 ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  405.         AV_WN32A(dst + 4             , \

  406.                  (AV_RN32(dst + 4             ) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  407.         AV_WN32A(dst + row_offset    , \

  408.                  (AV_RN32(dst + row_offset    ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  409.         AV_WN32A(dst + row_offset + 4, \

  410.                  (AV_RN32(dst + row_offset + 4) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  411.     } else { \

  412.         AV_WN16A(dst                 , \

  413.                  (AV_RN16(dst                 ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  414.         AV_WN16A(dst + 2             , \

  415.                  (AV_RN16(dst + 2             ) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  416.         AV_WN16A(dst + row_offset    , \

  417.                  (AV_RN16(dst + row_offset    ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  418.         AV_WN16A(dst + row_offset + 2, \

  419.                  (AV_RN16(dst + row_offset + 2) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  420.     }

  421. 

  422. 

  423. static int decode_cell_data(Indeo3DecodeContext *ctx, Cell *cell,

  424.                             uint8_t *block, uint8_t *ref_block,

  425.                             int pitch, int h_zoom, int v_zoom, int mode,

  426.                             const vqEntry *delta[2], int swap_quads[2],

  427.                             const uint8_t **data_ptr, const uint8_t *last_ptr)

  428. {

  429.     int           x, y, line, num_lines;

  430.     int           rle_blocks = 0;

  431.     uint8_t       code, *dst, *ref;

  432.     const vqEntry *delta_tab;

  433.     unsigned int  dyad1, dyad2;

  434.     uint64_t      pix64;

  435.     int           skip_flag = 0, is_top_of_cell, is_first_row = 1;

  436.     int           row_offset, blk_row_offset, line_offset;

  437. 

  438.     row_offset     =  pitch;

  439.     blk_row_offset = (row_offset << (2 + v_zoom)) - (cell->width << 2);

  440.     line_offset    = v_zoom ? row_offset : 0;

  441. 

  442.     if (cell->height & v_zoom || cell->width & h_zoom)

  443.         return IV3_BAD_DATA;

  444. 

  445.     for (y = 0; y < cell->height; is_first_row = 0, y += 1 + v_zoom) {

  446.         for (x = 0; x < cell->width; x += 1 + h_zoom) {

  447.             ref = ref_block;

  448.             dst = block;

  449. 

  450.             if (rle_blocks > 0) {

  451.                 if (mode <= 4) {

  452.                     RLE_BLOCK_COPY;

  453.                 } else if (mode == 10 && !cell->mv_ptr) {

  454.                     RLE_BLOCK_COPY_8;

  455.                 }

  456.                 rle_blocks--;

  457.             } else {

  458.                 for (line = 0; line < 4;) {

  459.                     num_lines = 1;

  460.                     is_top_of_cell = is_first_row && !line;

  461. 

  462.                     /* select primary VQ table for odd, secondary for even lines */

  463.                     if (mode <= 4)

  464.                         delta_tab = delta[line & 1];

  465.                     else

  466.                         delta_tab = delta[1];

  467.                     BUFFER_PRECHECK;

  468.                     code = bytestream_get_byte(data_ptr);

  469.                     if (code < 248) {

  470.                         if (code < delta_tab->num_dyads) {

  471.                             BUFFER_PRECHECK;

  472.                             dyad1 = bytestream_get_byte(data_ptr);

  473.                             dyad2 = code;

  474.                             if (dyad1 >= delta_tab->num_dyads || dyad1 >= 248)

  475.                                 return IV3_BAD_DATA;

  476.                         } else {

  477.                             /* process QUADS */

  478.                             code -= delta_tab->num_dyads;

  479.                             dyad1 = code / delta_tab->quad_exp;

  480.                             dyad2 = code % delta_tab->quad_exp;

  481.                             if (swap_quads[line & 1])

  482.                                 FFSWAP(unsigned int, dyad1, dyad2);

  483.                         }

  484.                         if (mode <= 4) {

  485.                             APPLY_DELTA_4;

  486.                         } else if (mode == 10 && !cell->mv_ptr) {

  487.                             APPLY_DELTA_8;

  488.                         } else {

  489.                             APPLY_DELTA_1011_INTER;

  490.                         }

  491.                     } else {

  492.                         /* process RLE codes */

  493.                         switch (code) {

  494.                         case RLE_ESC_FC:

  495.                             skip_flag  = 0;

  496.                             rle_blocks = 1;

  497.                             code       = 253;

  498.                             /* FALLTHROUGH */

  499.                         case RLE_ESC_FF:

  500.                         case RLE_ESC_FE:

  501.                         case RLE_ESC_FD:

  502.                             num_lines = 257 - code - line;

  503.                             if (num_lines <= 0)

  504.                                 return IV3_BAD_RLE;

  505.                             if (mode <= 4) {

  506.                                 RLE_LINES_COPY;

  507.                             } else if (mode == 10 && !cell->mv_ptr) {

  508.                                 RLE_LINES_COPY_M10;

  509.                             }

  510.                             break;

  511.                         case RLE_ESC_FB:

  512.                             BUFFER_PRECHECK;

  513.                             code = bytestream_get_byte(data_ptr);

  514.                             rle_blocks = (code & 0x1F) - 1; /* set block counter */

  515.                             if (code >= 64 || rle_blocks < 0)

  516.                                 return IV3_BAD_COUNTER;

  517.                             skip_flag = code & 0x20;

  518.                             num_lines = 4 - line; /* enforce next block processing */

  519.                             if (mode >= 10 || (cell->mv_ptr || !skip_flag)) {

  520.                                 if (mode <= 4) {

  521.                                     RLE_LINES_COPY;

  522.                                 } else if (mode == 10 && !cell->mv_ptr) {

  523.                                     RLE_LINES_COPY_M10;

  524.                                 }

  525.                             }

  526.                             break;

  527.                         case RLE_ESC_F9:

  528.                             skip_flag  = 1;

  529.                             rle_blocks = 1;

  530.                             /* FALLTHROUGH */

  531.                         case RLE_ESC_FA:

  532.                             if (line)

  533.                                 return IV3_BAD_RLE;

  534.                             num_lines = 4; /* enforce next block processing */

  535.                             if (cell->mv_ptr) {

  536.                                 if (mode <= 4) {

  537.                                     RLE_LINES_COPY;

  538.                                 } else if (mode == 10 && !cell->mv_ptr) {

  539.                                     RLE_LINES_COPY_M10;

  540.                                 }

  541.                             }

  542.                             break;

  543.                         default:

  544.                             return IV3_UNSUPPORTED;

  545.                         }

  546.                     }

  547. 

  548.                     line += num_lines;

  549.                     ref  += row_offset * (num_lines << v_zoom);

  550.                     dst  += row_offset * (num_lines << v_zoom);

  551.                 }

  552.             }

  553. 

  554.             /* move to next horizontal block */

  555.             block     += 4 << h_zoom;

  556.             ref_block += 4 << h_zoom;

  557.         }

  558. 

  559.         /* move to next line of blocks */

  560.         ref_block += blk_row_offset;

  561.         block     += blk_row_offset;

  562.     }

  563.     return IV3_NOERR;

  564. }

  565. 

  566. 

  567. /**

  568.  *  Decode a vector-quantized cell.

  569.  *  It consists of several routines, each of which handles one or more "modes"

  570.  *  with which a cell can be encoded.

  571.  *

  572.  *  @param ctx      pointer to the decoder context

  573.  *  @param avctx    ptr to the AVCodecContext

  574.  *  @param plane    pointer to the plane descriptor

  575.  *  @param cell     pointer to the cell  descriptor

  576.  *  @param data_ptr pointer to the compressed data

  577.  *  @param last_ptr pointer to the last byte to catch reads past end of buffer

  578.  *  @return         number of consumed bytes or negative number in case of error

  579.  */

  580. static int decode_cell(Indeo3DecodeContext *ctx, AVCodecContext *avctx,

  581.                        Plane *plane, Cell *cell, const uint8_t *data_ptr,

  582.                        const uint8_t *last_ptr)

  583. {

  584.     int           x, mv_x, mv_y, mode, vq_index, prim_indx, second_indx;

  585.     int           zoom_fac;

  586.     int           offset, error = 0, swap_quads[2];

  587.     uint8_t       code, *block, *ref_block = 0;

  588.     const vqEntry *delta[2];

  589.     const uint8_t *data_start = data_ptr;

  590. 

  591.     /* get coding mode and VQ table index from the VQ descriptor byte */

  592.     code     = *data_ptr++;

  593.     mode     = code >> 4;

  594.     vq_index = code & 0xF;

  595. 

  596.     /* setup output and reference pointers */

  597.     offset = (cell->ypos << 2) * plane->pitch + (cell->xpos << 2);

  598.     block  =  plane->pixels[ctx->buf_sel] + offset;

  599. 

  600.     if (!cell->mv_ptr) {

  601.         /* use previous line as reference for INTRA cells */

  602.         ref_block = block - plane->pitch;

  603.     } else if (mode >= 10) {

  604.         /* for mode 10 and 11 INTER first copy the predicted cell into the current one */

  605.         /* so we don't need to do data copying for each RLE code later */

  606.         int ret = copy_cell(ctx, plane, cell);

  607.         if (ret < 0)

  608.             return ret;

  609.     } else {

  610.         /* set the pointer to the reference pixels for modes 0-4 INTER */

  611.         mv_y      = cell->mv_ptr[0];

  612.         mv_x      = cell->mv_ptr[1];

  613. 

  614.         /* -1 because there is an extra line on top for prediction */

  615.         if ((cell->ypos << 2) + mv_y < -1 || (cell->xpos << 2) + mv_x < 0 ||

  616.             ((cell->ypos + cell->height) << 2) + mv_y > plane->height     ||

  617.             ((cell->xpos + cell->width)  << 2) + mv_x > plane->width) {

  618.             av_log(ctx->avctx, AV_LOG_ERROR,

  619.                    "Motion vectors point out of the frame.\n");

  620.             return AVERROR_INVALIDDATA;

  621.         }

  622. 

  623.         offset   += mv_y * plane->pitch + mv_x;

  624.         ref_block = plane->pixels[ctx->buf_sel ^ 1] + offset;

  625.     }

  626. 

  627.     /* select VQ tables as follows: */

  628.     /* modes 0 and 3 use only the primary table for all lines in a block */

  629.     /* while modes 1 and 4 switch between primary and secondary tables on alternate lines */

  630.     if (mode == 1 || mode == 4) {

  631.         code        = ctx->alt_quant[vq_index];

  632.         prim_indx   = (code >> 4)  + ctx->cb_offset;

  633.         second_indx = (code & 0xF) + ctx->cb_offset;

  634.     } else {

  635.         vq_index += ctx->cb_offset;

  636.         prim_indx = second_indx = vq_index;

  637.     }

  638. 

  639.     if (prim_indx >= 24 || second_indx >= 24) {

  640.         av_log(avctx, AV_LOG_ERROR, "Invalid VQ table indexes! Primary: %d, secondary: %d!\n",

  641.                prim_indx, second_indx);

  642.         return AVERROR_INVALIDDATA;

  643.     }

  644. 

  645.     delta[0] = &vq_tab[second_indx];

  646.     delta[1] = &vq_tab[prim_indx];

  647.     swap_quads[0] = second_indx >= 16;

  648.     swap_quads[1] = prim_indx   >= 16;

  649. 

  650.     /* requantize the prediction if VQ index of this cell differs from VQ index */

  651.     /* of the predicted cell in order to avoid overflows. */

  652.     if (vq_index >= 8 && ref_block) {

  653.         for (x = 0; x < cell->width << 2; x++)

  654.             ref_block[x] = requant_tab[vq_index & 7][ref_block[x] & 127];

  655.     }

  656. 

  657.     error = IV3_NOERR;

  658. 

  659.     switch (mode) {

  660.     case 0: /*------------------ MODES 0 & 1 (4x4 block processing) --------------------*/

  661.     case 1:

  662.     case 3: /*------------------ MODES 3 & 4 (4x8 block processing) --------------------*/

  663.     case 4:

  664.         if (mode >= 3 && cell->mv_ptr) {

  665.             av_log(avctx, AV_LOG_ERROR, "Attempt to apply Mode 3/4 to an INTER cell!\n");

  666.             return AVERROR_INVALIDDATA;

  667.         }

  668. 

  669.         zoom_fac = mode >= 3;

  670.         error = decode_cell_data(ctx, cell, block, ref_block, plane->pitch,

  671.                                  0, zoom_fac, mode, delta, swap_quads,

  672.                                  &data_ptr, last_ptr);

  673.         break;

  674.     case 10: /*-------------------- MODE 10 (8x8 block processing) ---------------------*/

  675.     case 11: /*----------------- MODE 11 (4x8 INTER block processing) ------------------*/

  676.         if (mode == 10 && !cell->mv_ptr) { /* MODE 10 INTRA processing */

  677.             error = decode_cell_data(ctx, cell, block, ref_block, plane->pitch,

  678.                                      1, 1, mode, delta, swap_quads,

  679.                                      &data_ptr, last_ptr);

  680.         } else { /* mode 10 and 11 INTER processing */

  681.             if (mode == 11 && !cell->mv_ptr) {

  682.                av_log(avctx, AV_LOG_ERROR, "Attempt to use Mode 11 for an INTRA cell!\n");

  683.                return AVERROR_INVALIDDATA;

  684.             }

  685. 

  686.             zoom_fac = mode == 10;

  687.             error = decode_cell_data(ctx, cell, block, ref_block, plane->pitch,

  688.                                      zoom_fac, 1, mode, delta, swap_quads,

  689.                                      &data_ptr, last_ptr);

  690.         }

  691.         break;

  692.     default:

  693.         av_log(avctx, AV_LOG_ERROR, "Unsupported coding mode: %d\n", mode);

  694.         return AVERROR_INVALIDDATA;

  695.     }//switch mode

  696. 

  697.     switch (error) {

  698.     case IV3_BAD_RLE:

  699.         av_log(avctx, AV_LOG_ERROR, "Mode %d: RLE code %X is not allowed at the current line\n",

  700.                mode, data_ptr[-1]);

  701.         return AVERROR_INVALIDDATA;

  702.     case IV3_BAD_DATA:

  703.         av_log(avctx, AV_LOG_ERROR, "Mode %d: invalid VQ data\n", mode);

  704.         return AVERROR_INVALIDDATA;

  705.     case IV3_BAD_COUNTER:

  706.         av_log(avctx, AV_LOG_ERROR, "Mode %d: RLE-FB invalid counter: %d\n", mode, code);

  707.         return AVERROR_INVALIDDATA;

  708.     case IV3_UNSUPPORTED:

  709.         av_log(avctx, AV_LOG_ERROR, "Mode %d: unsupported RLE code: %X\n", mode, data_ptr[-1]);

  710.         return AVERROR_INVALIDDATA;

  711.     case IV3_OUT_OF_DATA:

  712.         av_log(avctx, AV_LOG_ERROR, "Mode %d: attempt to read past end of buffer\n", mode);

  713.         return AVERROR_INVALIDDATA;

  714.     }

  715. 

  716.     return data_ptr - data_start; /* report number of bytes consumed from the input buffer */

  717. }

  718. 

  719. 

  720. /* Binary tree codes. */

  721. enum {

  722.     H_SPLIT    = 0,

  723.     V_SPLIT    = 1,

  724.     INTRA_NULL = 2,

  725.     INTER_DATA = 3

  726. };

  727. 

  728. 

  729. #define SPLIT_CELL(size, new_size) (new_size) = ((size) > 2) ? ((((size) + 2) >> 2) << 1) : 1

  730. 

  731. #define UPDATE_BITPOS(n) \

  732.     ctx->skip_bits  += (n); \

  733.     ctx->need_resync = 1

  734. 

  735. #define RESYNC_BITSTREAM \

  736.     if (ctx->need_resync && !(get_bits_count(&ctx->gb) & 7)) { \

  737.         skip_bits_long(&ctx->gb, ctx->skip_bits);              \

  738.         ctx->skip_bits   = 0;                                  \

  739.         ctx->need_resync = 0;                                  \

  740.     }

  741. 

  742. #define CHECK_CELL \

  743.     if (curr_cell.xpos + curr_cell.width > (plane->width >> 2) ||               \

  744.         curr_cell.ypos + curr_cell.height > (plane->height >> 2)) {             \

  745.         av_log(avctx, AV_LOG_ERROR, "Invalid cell: x=%d, y=%d, w=%d, h=%d\n",   \

  746.                curr_cell.xpos, curr_cell.ypos, curr_cell.width, curr_cell.height); \

  747.         return AVERROR_INVALIDDATA;                                                              \

  748.     }

  749. 

  750. 

  751. static int parse_bintree(Indeo3DecodeContext *ctx, AVCodecContext *avctx,

  752.                          Plane *plane, int code, Cell *ref_cell,

  753.                          const int depth, const int strip_width)

  754. {

  755.     Cell    curr_cell;

  756.     int     bytes_used, ret;

  757. 

  758.     if (depth <= 0) {

  759.         av_log(avctx, AV_LOG_ERROR, "Stack overflow (corrupted binary tree)!\n");

  760.         return AVERROR_INVALIDDATA; // unwind recursion

  761.     }

  762. 

  763.     curr_cell = *ref_cell; // clone parent cell

  764.     if (code == H_SPLIT) {

  765.         SPLIT_CELL(ref_cell->height, curr_cell.height);

  766.         ref_cell->ypos   += curr_cell.height;

  767.         ref_cell->height -= curr_cell.height;

  768.         if (ref_cell->height <= 0 || curr_cell.height <= 0)

  769.             return AVERROR_INVALIDDATA;

  770.     } else if (code == V_SPLIT) {

  771.         if (curr_cell.width > strip_width) {

  772.             /* split strip */

  773.             curr_cell.width = (curr_cell.width <= (strip_width << 1) ? 1 : 2) * strip_width;

  774.         } else

  775.             SPLIT_CELL(ref_cell->width, curr_cell.width);

  776.         ref_cell->xpos  += curr_cell.width;

  777.         ref_cell->width -= curr_cell.width;

  778.         if (ref_cell->width <= 0 || curr_cell.width <= 0)

  779.             return AVERROR_INVALIDDATA;

  780.     }

  781. 

  782.     while (get_bits_left(&ctx->gb) >= 2) { /* loop until return */

  783.         RESYNC_BITSTREAM;

  784.         switch (code = get_bits(&ctx->gb, 2)) {

  785.         case H_SPLIT:

  786.         case V_SPLIT:

  787.             if (parse_bintree(ctx, avctx, plane, code, &curr_cell, depth - 1, strip_width))

  788.                 return AVERROR_INVALIDDATA;

  789.             break;

  790.         case INTRA_NULL:

  791.             if (!curr_cell.tree) { /* MC tree INTRA code */

  792.                 curr_cell.mv_ptr = 0; /* mark the current strip as INTRA */

  793.                 curr_cell.tree   = 1; /* enter the VQ tree */

  794.             } else { /* VQ tree NULL code */

  795.                 RESYNC_BITSTREAM;

  796.                 code = get_bits(&ctx->gb, 2);

  797.                 if (code >= 2) {

  798.                     av_log(avctx, AV_LOG_ERROR, "Invalid VQ_NULL code: %d\n", code);

  799.                     return AVERROR_INVALIDDATA;

  800.                 }

  801.                 if (code == 1)

  802.                     av_log(avctx, AV_LOG_ERROR, "SkipCell procedure not implemented yet!\n");

  803. 

  804.                 CHECK_CELL

  805.                 if (!curr_cell.mv_ptr)

  806.                     return AVERROR_INVALIDDATA;

  807. 

  808.                 ret = copy_cell(ctx, plane, &curr_cell);

  809.                 return ret;

  810.             }

  811.             break;

  812.         case INTER_DATA:

  813.             if (!curr_cell.tree) { /* MC tree INTER code */

  814.                 unsigned mv_idx;

  815.                 /* get motion vector index and setup the pointer to the mv set */

  816.                 if (!ctx->need_resync)

  817.                     ctx->next_cell_data = &ctx->gb.buffer[(get_bits_count(&ctx->gb) + 7) >> 3];

  818.                 if (ctx->next_cell_data >= ctx->last_byte) {

  819.                     av_log(avctx, AV_LOG_ERROR, "motion vector out of array\n");

  820.                     return AVERROR_INVALIDDATA;

  821.                 }

  822.                 mv_idx = *(ctx->next_cell_data++);

  823.                 if (mv_idx >= ctx->num_vectors) {

  824.                     av_log(avctx, AV_LOG_ERROR, "motion vector index out of range\n");

  825.                     return AVERROR_INVALIDDATA;

  826.                 }

  827.                 curr_cell.mv_ptr = &ctx->mc_vectors[mv_idx << 1];

  828.                 curr_cell.tree   = 1; /* enter the VQ tree */

  829.                 UPDATE_BITPOS(8);

  830.             } else { /* VQ tree DATA code */

  831.                 if (!ctx->need_resync)

  832.                     ctx->next_cell_data = &ctx->gb.buffer[(get_bits_count(&ctx->gb) + 7) >> 3];

  833. 

  834.                 CHECK_CELL

  835.                 bytes_used = decode_cell(ctx, avctx, plane, &curr_cell,

  836.                                          ctx->next_cell_data, ctx->last_byte);

  837.                 if (bytes_used < 0)

  838.                     return AVERROR_INVALIDDATA;

  839. 

  840.                 UPDATE_BITPOS(bytes_used << 3);

  841.                 ctx->next_cell_data += bytes_used;

  842.                 return 0;

  843.             }

  844.             break;

  845.         }

  846.     }//while

  847. 

  848.     return AVERROR_INVALIDDATA;

  849. }

  850. 

  851. 

  852. static int decode_plane(Indeo3DecodeContext *ctx, AVCodecContext *avctx,

  853.                         Plane *plane, const uint8_t *data, int32_t data_size,

  854.                         int32_t strip_width)

  855. {

  856.     Cell            curr_cell;

  857.     unsigned        num_vectors;

  858. 

  859.     /* each plane data starts with mc_vector_count field, */

  860.     /* an optional array of motion vectors followed by the vq data */

  861.     num_vectors = bytestream_get_le32(&data); data_size -= 4;

  862.     if (num_vectors > 256) {

  863.         av_log(ctx->avctx, AV_LOG_ERROR,

  864.                "Read invalid number of motion vectors %d\n", num_vectors);

  865.         return AVERROR_INVALIDDATA;

  866.     }

  867.     if (num_vectors * 2 > data_size)

  868.         return AVERROR_INVALIDDATA;

  869. 

  870.     ctx->num_vectors = num_vectors;

  871.     ctx->mc_vectors  = num_vectors ? data : 0;

  872. 

  873.     /* init the bitreader */

  874.     init_get_bits(&ctx->gb, &data[num_vectors * 2], (data_size - num_vectors * 2) << 3);

  875.     ctx->skip_bits   = 0;

  876.     ctx->need_resync = 0;

  877. 

  878.     ctx->last_byte = data + data_size;

  879. 

  880.     /* initialize the 1st cell and set its dimensions to whole plane */

  881.     curr_cell.xpos   = curr_cell.ypos = 0;

  882.     curr_cell.width  = plane->width  >> 2;

  883.     curr_cell.height = plane->height >> 2;

  884.     curr_cell.tree   = 0; // we are in the MC tree now

  885.     curr_cell.mv_ptr = 0; // no motion vector = INTRA cell

  886. 

  887.     return parse_bintree(ctx, avctx, plane, INTRA_NULL, &curr_cell, CELL_STACK_MAX, strip_width);

  888. }

  889. 

  890. 

  891. #define OS_HDR_ID   MKBETAG('F', 'R', 'M', 'H')

  892. 

  893. static int decode_frame_headers(Indeo3DecodeContext *ctx, AVCodecContext *avctx,

  894.                                 const uint8_t *buf, int buf_size)

  895. {

  896.     GetByteContext gb;

  897.     const uint8_t   *bs_hdr;

  898.     uint32_t        frame_num, word2, check_sum, data_size;

  899.     uint32_t        y_offset, u_offset, v_offset, starts[3], ends[3];

  900.     uint16_t        height, width;

  901.     int             i, j;

  902. 

  903.     bytestream2_init(&gb, buf, buf_size);

  904. 

  905.     /* parse and check the OS header */

  906.     frame_num = bytestream2_get_le32(&gb);

  907.     word2     = bytestream2_get_le32(&gb);

  908.     check_sum = bytestream2_get_le32(&gb);

  909.     data_size = bytestream2_get_le32(&gb);

  910. 

  911.     if ((frame_num ^ word2 ^ data_size ^ OS_HDR_ID) != check_sum) {

  912.         av_log(avctx, AV_LOG_ERROR, "OS header checksum mismatch!\n");

  913.         return AVERROR_INVALIDDATA;

  914.     }

  915. 

  916.     /* parse the bitstream header */

  917.     bs_hdr = gb.buffer;

  918. 

  919.     if (bytestream2_get_le16(&gb) != 32) {

  920.         av_log(avctx, AV_LOG_ERROR, "Unsupported codec version!\n");

  921.         return AVERROR_INVALIDDATA;

  922.     }

  923. 

  924.     ctx->frame_num   =  frame_num;

  925.     ctx->frame_flags =  bytestream2_get_le16(&gb);

  926.     ctx->data_size   = (bytestream2_get_le32(&gb) + 7) >> 3;

  927.     ctx->cb_offset   =  bytestream2_get_byte(&gb);

  928. 

  929.     if (ctx->data_size == 16)

  930.         return 4;

  931.     ctx->data_size = FFMIN(ctx->data_size, buf_size - 16);

  932. 

  933.     bytestream2_skip(&gb, 3); // skip reserved byte and checksum

  934. 

  935.     /* check frame dimensions */

  936.     height = bytestream2_get_le16(&gb);

  937.     width  = bytestream2_get_le16(&gb);

  938.     if (av_image_check_size(width, height, 0, avctx))

  939.         return AVERROR_INVALIDDATA;

  940. 

  941.     if (width != ctx->width || height != ctx->height) {

  942.         int res;

  943. 

  944.         av_dlog(avctx, "Frame dimensions changed!\n");

  945. 

  946.         if (width  < 16 || width  > 640 ||

  947.             height < 16 || height > 480 ||

  948.             width  &  3 || height &   3) {

  949.             av_log(avctx, AV_LOG_ERROR,

  950.                    "Invalid picture dimensions: %d x %d!\n", width, height);

  951.             return AVERROR_INVALIDDATA;

  952.         }

  953.         free_frame_buffers(ctx);

  954.         if ((res = allocate_frame_buffers(ctx, avctx, width, height)) < 0)

  955.              return res;

  956.         avcodec_set_dimensions(avctx, width, height);

  957.     }

  958. 

  959.     y_offset = bytestream2_get_le32(&gb);

  960.     v_offset = bytestream2_get_le32(&gb);

  961.     u_offset = bytestream2_get_le32(&gb);

  962.     bytestream2_skip(&gb, 4);

  963. 

  964.     /* unfortunately there is no common order of planes in the buffer */

  965.     /* so we use that sorting algo for determining planes data sizes  */

  966.     starts[0] = y_offset;

  967.     starts[1] = v_offset;

  968.     starts[2] = u_offset;

  969. 

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

  971.         ends[j] = ctx->data_size;

  972.         for (i = 2; i >= 0; i--)

  973.             if (starts[i] < ends[j] && starts[i] > starts[j])

  974.                 ends[j] = starts[i];

  975.     }

  976. 

  977.     ctx->y_data_size = ends[0] - starts[0];

  978.     ctx->v_data_size = ends[1] - starts[1];

  979.     ctx->u_data_size = ends[2] - starts[2];

  980.     if (FFMAX3(y_offset, v_offset, u_offset) >= ctx->data_size - 16 ||

  981.         FFMIN3(y_offset, v_offset, u_offset) < gb.buffer - bs_hdr + 16 ||

  982.         FFMIN3(ctx->y_data_size, ctx->v_data_size, ctx->u_data_size) <= 0) {

  983.         av_log(avctx, AV_LOG_ERROR, "One of the y/u/v offsets is invalid\n");

  984.         return AVERROR_INVALIDDATA;

  985.     }

  986. 

  987.     ctx->y_data_ptr = bs_hdr + y_offset;

  988.     ctx->v_data_ptr = bs_hdr + v_offset;

  989.     ctx->u_data_ptr = bs_hdr + u_offset;

  990.     ctx->alt_quant  = gb.buffer;

  991. 

  992.     if (ctx->data_size == 16) {

  993.         av_log(avctx, AV_LOG_DEBUG, "Sync frame encountered!\n");

  994.         return 16;

  995.     }

  996. 

  997.     if (ctx->frame_flags & BS_8BIT_PEL) {

  998.         avpriv_request_sample(avctx, "8-bit pixel format");

  999.         return AVERROR_PATCHWELCOME;

  1000.     }

  1001. 

  1002.     if (ctx->frame_flags & BS_MV_X_HALF || ctx->frame_flags & BS_MV_Y_HALF) {

  1003.         avpriv_request_sample(avctx, "Halfpel motion vectors");

  1004.         return AVERROR_PATCHWELCOME;

  1005.     }

  1006. 

  1007.     return 0;

  1008. }

  1009. 

  1010. 

  1011. /**

  1012.  *  Convert and output the current plane.

  1013.  *  All pixel values will be upsampled by shifting right by one bit.

  1014.  *

  1015.  *  @param[in]  plane        pointer to the descriptor of the plane being processed

  1016.  *  @param[in]  buf_sel      indicates which frame buffer the input data stored in

  1017.  *  @param[out] dst          pointer to the buffer receiving converted pixels

  1018.  *  @param[in]  dst_pitch    pitch for moving to the next y line

  1019.  *  @param[in]  dst_height   output plane height

  1020.  */

  1021. static void output_plane(const Plane *plane, int buf_sel, uint8_t *dst,

  1022.                          int dst_pitch, int dst_height)

  1023. {

  1024.     int             x,y;

  1025.     const uint8_t   *src  = plane->pixels[buf_sel];

  1026.     uint32_t        pitch = plane->pitch;

  1027. 

  1028.     dst_height = FFMIN(dst_height, plane->height);

  1029.     for (y = 0; y < dst_height; y++) {

  1030.         /* convert four pixels at once using SWAR */

  1031.         for (x = 0; x < plane->width >> 2; x++) {

  1032.             AV_WN32A(dst, (AV_RN32A(src) & 0x7F7F7F7F) << 1);

  1033.             src += 4;

  1034.             dst += 4;

  1035.         }

  1036. 

  1037.         for (x <<= 2; x < plane->width; x++)

  1038.             *dst++ = *src++ << 1;

  1039. 

  1040.         src += pitch     - plane->width;

  1041.         dst += dst_pitch - plane->width;

  1042.     }

  1043. }

  1044. 

  1045. 

  1046. static av_cold int decode_init(AVCodecContext *avctx)

  1047. {

  1048.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1049. 

  1050.     ctx->avctx     = avctx;

  1051.     avctx->pix_fmt = AV_PIX_FMT_YUV410P;

  1052. 

  1053.     build_requant_tab();

  1054. 

  1055.     ff_hpeldsp_init(&ctx->hdsp, avctx->flags);

  1056. 

  1057.     return allocate_frame_buffers(ctx, avctx, avctx->width, avctx->height);

  1058. }

  1059. 

  1060. 

  1061. static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

  1062.                         AVPacket *avpkt)

  1063. {

  1064.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1065.     const uint8_t *buf = avpkt->data;

  1066.     int buf_size       = avpkt->size;

  1067.     AVFrame *frame     = data;

  1068.     int res;

  1069. 

  1070.     res = decode_frame_headers(ctx, avctx, buf, buf_size);

  1071.     if (res < 0)

  1072.         return res;

  1073. 

  1074.     /* skip sync(null) frames */

  1075.     if (res) {

  1076.         // we have processed 16 bytes but no data was decoded

  1077.         *got_frame = 0;

  1078.         return buf_size;

  1079.     }

  1080. 

  1081.     /* skip droppable INTER frames if requested */

  1082.     if (ctx->frame_flags & BS_NONREF &&

  1083.        (avctx->skip_frame >= AVDISCARD_NONREF))

  1084.         return 0;

  1085. 

  1086.     /* skip INTER frames if requested */

  1087.     if (!(ctx->frame_flags & BS_KEYFRAME) && avctx->skip_frame >= AVDISCARD_NONKEY)

  1088.         return 0;

  1089. 

  1090.     /* use BS_BUFFER flag for buffer switching */

  1091.     ctx->buf_sel = (ctx->frame_flags >> BS_BUFFER) & 1;

  1092. 

  1093.     if ((res = ff_get_buffer(avctx, frame, 0)) < 0)

  1094.         return res;

  1095. 

  1096.     /* decode luma plane */

  1097.     if ((res = decode_plane(ctx, avctx, ctx->planes, ctx->y_data_ptr, ctx->y_data_size, 40)))

  1098.         return res;

  1099. 

  1100.     /* decode chroma planes */

  1101.     if ((res = decode_plane(ctx, avctx, &ctx->planes[1], ctx->u_data_ptr, ctx->u_data_size, 10)))

  1102.         return res;

  1103. 

  1104.     if ((res = decode_plane(ctx, avctx, &ctx->planes[2], ctx->v_data_ptr, ctx->v_data_size, 10)))

  1105.         return res;

  1106. 

  1107.     output_plane(&ctx->planes[0], ctx->buf_sel,

  1108.                  frame->data[0], frame->linesize[0],

  1109.                  avctx->height);

  1110.     output_plane(&ctx->planes[1], ctx->buf_sel,

  1111.                  frame->data[1], frame->linesize[1],

  1112.                  (avctx->height + 3) >> 2);

  1113.     output_plane(&ctx->planes[2], ctx->buf_sel,

  1114.                  frame->data[2], frame->linesize[2],

  1115.                  (avctx->height + 3) >> 2);

  1116. 

  1117.     *got_frame = 1;

  1118. 

  1119.     return buf_size;

  1120. }

  1121. 

  1122. 

  1123. static av_cold int decode_close(AVCodecContext *avctx)

  1124. {

  1125.     free_frame_buffers(avctx->priv_data);

  1126. 

  1127.     return 0;

  1128. }

  1129. 

  1130. AVCodec ff_indeo3_decoder = {

  1131.     .name           = "indeo3",

  1132.     .type           = AVMEDIA_TYPE_VIDEO,

  1133.     .id             = AV_CODEC_ID_INDEO3,

  1134.     .priv_data_size = sizeof(Indeo3DecodeContext),

  1135.     .init           = decode_init,

  1136.     .close          = decode_close,

  1137.     .decode         = decode_frame,

  1138.     .capabilities   = CODEC_CAP_DR1,

  1139.     .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo 3"),

  1140. };