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FFmpeg/libavcodec/indeo3.c

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  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 "dsputil.h"

  36. #include "bytestream.h"

  37. #include "get_bits.h"

  38. 

  39. #include "indeo3data.h"

  40. 

  41. /* RLE opcodes. */

  42. enum {

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

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

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

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

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

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

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

  50. };

  51. 

  52. 

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

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

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

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

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

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

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

  60. 

  61. 

  62. typedef struct Plane {

  63.     uint8_t         *buffers[2];

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

  65.     uint32_t        width;

  66.     uint32_t        height;

  67.     uint32_t        pitch;

  68. } Plane;

  69. 

  70. #define CELL_STACK_MAX  20

  71. 

  72. typedef struct Cell {

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

  74.     int16_t         ypos;

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

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

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

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

  79. } Cell;

  80. 

  81. typedef struct Indeo3DecodeContext {

  82.     AVCodecContext *avctx;

  83.     AVFrame         frame;

  84.     DSPContext      dsp;

  85. 

  86.     GetBitContext   gb;

  87.     int             need_resync;

  88.     int             skip_bits;

  89.     const uint8_t   *next_cell_data;

  90.     const uint8_t   *last_byte;

  91.     const int8_t    *mc_vectors;

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

  93. 

  94.     int16_t         width, height;

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

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

  97.     uint16_t        frame_flags;    ///< frame properties

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

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

  100.     const uint8_t   *y_data_ptr;

  101.     const uint8_t   *v_data_ptr;

  102.     const uint8_t   *u_data_ptr;

  103.     int32_t         y_data_size;

  104.     int32_t         v_data_size;

  105.     int32_t         u_data_size;

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

  107.     Plane           planes[3];

  108. } Indeo3DecodeContext;

  109. 

  110. 

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

  112. 

  113. /*

  114.  *  Build the static requantization table.

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

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

  117.  */

  118. static av_cold void build_requant_tab(void)

  119. {

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

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

  122. 

  123.     int i, j, step;

  124. 

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

  126.         step = i + 2;

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

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

  129.     }

  130. 

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

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

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

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

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

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

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

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

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

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

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

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

  143. 

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

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

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

  147. }

  148. 

  149. 

  150. static av_cold int allocate_frame_buffers(Indeo3DecodeContext *ctx,

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

  152. {

  153.     int p, chroma_width, chroma_height;

  154.     int luma_pitch, chroma_pitch, luma_size, chroma_size;

  155. 

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

  157.         luma_height < 16 || luma_height > 480 ||

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

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

  160.                luma_width, luma_height);

  161.         return AVERROR_INVALIDDATA;

  162.     }

  163. 

  164.     ctx->width  = luma_width ;

  165.     ctx->height = luma_height;

  166. 

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

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

  169. 

  170.     luma_pitch   = FFALIGN(luma_width,   16);

  171.     chroma_pitch = FFALIGN(chroma_width, 16);

  172. 

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

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

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

  176. 

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

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

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

  180. 

  181.     /* allocate frame buffers */

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

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

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

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

  186. 

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

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

  189. 

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

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

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

  193. 

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

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

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

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

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

  199.     }

  200. 

  201.     return 0;

  202. }

  203. 

  204. 

  205. static av_cold void free_frame_buffers(Indeo3DecodeContext *ctx)

  206. {

  207.     int p;

  208. 

  209.     ctx->width=

  210.     ctx->height= 0;

  211. 

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

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

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

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

  216.     }

  217. }

  218. 

  219. 

  220. /**

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

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

  223.  *

  224.  *  @param ctx      pointer to the decoder context

  225.  *  @param plane    pointer to the plane descriptor

  226.  *  @param cell     pointer to the cell  descriptor

  227.  */

  228. static void copy_cell(Indeo3DecodeContext *ctx, Plane *plane, Cell *cell)

  229. {

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

  231.     uint8_t *src, *dst;

  232. 

  233.     /* setup output and reference pointers */

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

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

  236.     if(cell->mv_ptr){

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

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

  239.     }else

  240.         mv_x= mv_y= 0;

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

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

  243. 

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

  245. 

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

  247.         /* copy using 16xH blocks */

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

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

  250.                 ctx->dsp.put_no_rnd_pixels_tab[0][0](dst, src, plane->pitch, h);

  251.         }

  252. 

  253.         /* copy using 8xH blocks */

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

  255.             ctx->dsp.put_no_rnd_pixels_tab[1][0](dst, src, plane->pitch, h);

  256.             w -= 2;

  257.             src += 8;

  258.             dst += 8;

  259.         }

  260. 

  261.         if (w >= 1) {

  262.             copy_block4(dst, src, plane->pitch, plane->pitch, h);

  263.             w--;

  264.             src += 4;

  265.             dst += 4;

  266.         }

  267.     }

  268. }

  269. 

  270. 

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

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

  273.     AV_WN32A(dst, ((AV_RN32A(src) + AV_RN32A(ref)) >> 1) & 0x7F7F7F7FUL)

  274. 

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

  276.     AV_WN64A(dst, ((AV_RN64A(src) + AV_RN64A(ref)) >> 1) & 0x7F7F7F7F7F7F7F7FULL)

  277. 

  278. 

  279. /*

  280.  *  Replicate each even pixel as follows:

  281.  *  ABCDEFGH -> AACCEEGG

  282.  */

  283. static inline uint64_t replicate64(uint64_t a) {

  284. #if HAVE_BIGENDIAN

  285.     a &= 0xFF00FF00FF00FF00ULL;

  286.     a |= a >> 8;

  287. #else

  288.     a &= 0x00FF00FF00FF00FFULL;

  289.     a |= a << 8;

  290. #endif

  291.     return a;

  292. }

  293. 

  294. static inline uint32_t replicate32(uint32_t a) {

  295. #if HAVE_BIGENDIAN

  296.     a &= 0xFF00FF00UL;

  297.     a |= a >> 8;

  298. #else

  299.     a &= 0x00FF00FFUL;

  300.     a |= a << 8;

  301. #endif

  302.     return a;

  303. }

  304. 

  305. 

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

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

  308.                            int32_t row_offset)

  309. {

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

  311.         AV_WN64A(dst, pix);

  312. }

  313. 

  314. 

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

  316. enum {

  317.     IV3_NOERR       = 0,

  318.     IV3_BAD_RLE     = 1,

  319.     IV3_BAD_DATA    = 2,

  320.     IV3_BAD_COUNTER = 3,

  321.     IV3_UNSUPPORTED = 4,

  322.     IV3_OUT_OF_DATA = 5

  323. };

  324. 

  325. 

  326. #define BUFFER_PRECHECK \

  327. if (*data_ptr >= last_ptr) \

  328.     return IV3_OUT_OF_DATA; \

  329. 

  330. #define RLE_BLOCK_COPY \

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

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

  333. 

  334. #define RLE_BLOCK_COPY_8 \

  335.     pix64 = AV_RN64A(ref);\

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

  337.         pix64 = replicate64(pix64);\

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

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

  340.     } else \

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

  342. 

  343. #define RLE_LINES_COPY \

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

  345. 

  346. #define RLE_LINES_COPY_M10 \

  347.     pix64 = AV_RN64A(ref);\

  348.     if (is_top_of_cell) {\

  349.         pix64 = replicate64(pix64);\

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

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

  352.     } else \

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

  354. 

  355. #define APPLY_DELTA_4 \

  356.     AV_WN16A(dst + line_offset    ,\

  357.              (AV_RN16A(ref    ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  358.     AV_WN16A(dst + line_offset + 2,\

  359.              (AV_RN16A(ref + 2) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  360.     if (mode >= 3) {\

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

  362.             AV_COPY32(dst, dst + row_offset);\

  363.         } else {\

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

  365.         }\

  366.     }

  367. 

  368. #define APPLY_DELTA_8 \

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

  370.     if (is_top_of_cell) { \

  371.         AV_WN32A(dst + row_offset    , \

  372.                  (replicate32(AV_RN32A(ref    )) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  373.         AV_WN32A(dst + row_offset + 4, \

  374.                  (replicate32(AV_RN32A(ref + 4)) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  375.     } else { \

  376.         AV_WN32A(dst + row_offset    , \

  377.                  (AV_RN32A(ref    ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  378.         AV_WN32A(dst + row_offset + 4, \

  379.                  (AV_RN32A(ref + 4) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  380.     } \

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

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

  383.     /* otherwise - interpolate */\

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

  385.         AV_COPY64(dst, dst + row_offset);\

  386.     } else \

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

  388. 

  389. 

  390. #define APPLY_DELTA_1011_INTER \

  391.     if (mode == 10) { \

  392.         AV_WN32A(dst                 , \

  393.                  (AV_RN32A(dst                 ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  394.         AV_WN32A(dst + 4             , \

  395.                  (AV_RN32A(dst + 4             ) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  396.         AV_WN32A(dst + row_offset    , \

  397.                  (AV_RN32A(dst + row_offset    ) + delta_tab->deltas_m10[dyad1]) & 0x7F7F7F7F);\

  398.         AV_WN32A(dst + row_offset + 4, \

  399.                  (AV_RN32A(dst + row_offset + 4) + delta_tab->deltas_m10[dyad2]) & 0x7F7F7F7F);\

  400.     } else { \

  401.         AV_WN16A(dst                 , \

  402.                  (AV_RN16A(dst                 ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  403.         AV_WN16A(dst + 2             , \

  404.                  (AV_RN16A(dst + 2             ) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  405.         AV_WN16A(dst + row_offset    , \

  406.                  (AV_RN16A(dst + row_offset    ) + delta_tab->deltas[dyad1]) & 0x7F7F);\

  407.         AV_WN16A(dst + row_offset + 2, \

  408.                  (AV_RN16A(dst + row_offset + 2) + delta_tab->deltas[dyad2]) & 0x7F7F);\

  409.     }

  410. 

  411. 

  412. static int decode_cell_data(Cell *cell, uint8_t *block, uint8_t *ref_block,

  413.                             int pitch, int h_zoom, int v_zoom, int mode,

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

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

  416. {

  417.     int           x, y, line, num_lines;

  418.     int           rle_blocks = 0;

  419.     uint8_t       code, *dst, *ref;

  420.     const vqEntry *delta_tab;

  421.     unsigned int  dyad1, dyad2;

  422.     uint64_t      pix64;

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

  424.     int           row_offset, blk_row_offset, line_offset;

  425. 

  426.     row_offset     =  pitch;

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

  428.     line_offset    = v_zoom ? row_offset : 0;

  429. 

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

  431.         return IV3_BAD_DATA;

  432. 

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

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

  435.             ref = ref_block;

  436.             dst = block;

  437. 

  438.             if (rle_blocks > 0) {

  439.                 if (mode <= 4) {

  440.                     RLE_BLOCK_COPY;

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

  442.                     RLE_BLOCK_COPY_8;

  443.                 }

  444.                 rle_blocks--;

  445.             } else {

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

  447.                     num_lines = 1;

  448.                     is_top_of_cell = is_first_row && !line;

  449. 

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

  451.                     if (mode <= 4)

  452.                         delta_tab = delta[line & 1];

  453.                     else

  454.                         delta_tab = delta[1];

  455.                     BUFFER_PRECHECK;

  456.                     code = bytestream_get_byte(data_ptr);

  457.                     if (code < 248) {

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

  459.                             BUFFER_PRECHECK;

  460.                             dyad1 = bytestream_get_byte(data_ptr);

  461.                             dyad2 = code;

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

  463.                                 return IV3_BAD_DATA;

  464.                         } else {

  465.                             /* process QUADS */

  466.                             code -= delta_tab->num_dyads;

  467.                             dyad1 = code / delta_tab->quad_exp;

  468.                             dyad2 = code % delta_tab->quad_exp;

  469.                             if (swap_quads[line & 1])

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

  471.                         }

  472.                         if (mode <= 4) {

  473.                             APPLY_DELTA_4;

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

  475.                             APPLY_DELTA_8;

  476.                         } else {

  477.                             APPLY_DELTA_1011_INTER;

  478.                         }

  479.                     } else {

  480.                         /* process RLE codes */

  481.                         switch (code) {

  482.                         case RLE_ESC_FC:

  483.                             skip_flag  = 0;

  484.                             rle_blocks = 1;

  485.                             code       = 253;

  486.                             /* FALLTHROUGH */

  487.                         case RLE_ESC_FF:

  488.                         case RLE_ESC_FE:

  489.                         case RLE_ESC_FD:

  490.                             num_lines = 257 - code - line;

  491.                             if (num_lines <= 0)

  492.                                 return IV3_BAD_RLE;

  493.                             if (mode <= 4) {

  494.                                 RLE_LINES_COPY;

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

  496.                                 RLE_LINES_COPY_M10;

  497.                             }

  498.                             break;

  499.                         case RLE_ESC_FB:

  500.                             BUFFER_PRECHECK;

  501.                             code = bytestream_get_byte(data_ptr);

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

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

  504.                                 return IV3_BAD_COUNTER;

  505.                             skip_flag = code & 0x20;

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

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

  508.                                 if (mode <= 4) {

  509.                                     RLE_LINES_COPY;

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

  511.                                     RLE_LINES_COPY_M10;

  512.                                 }

  513.                             }

  514.                             break;

  515.                         case RLE_ESC_F9:

  516.                             skip_flag  = 1;

  517.                             rle_blocks = 1;

  518.                             /* FALLTHROUGH */

  519.                         case RLE_ESC_FA:

  520.                             if (line)

  521.                                 return IV3_BAD_RLE;

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

  523.                             if (cell->mv_ptr) {

  524.                                 if (mode <= 4) {

  525.                                     RLE_LINES_COPY;

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

  527.                                     RLE_LINES_COPY_M10;

  528.                                 }

  529.                             }

  530.                             break;

  531.                         default:

  532.                             return IV3_UNSUPPORTED;

  533.                         }

  534.                     }

  535. 

  536.                     line += num_lines;

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

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

  539.                 }

  540.             }

  541. 

  542.             /* move to next horizontal block */

  543.             block     += 4 << h_zoom;

  544.             ref_block += 4 << h_zoom;

  545.         }

  546. 

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

  548.         ref_block += blk_row_offset;

  549.         block     += blk_row_offset;

  550.     }

  551.     return IV3_NOERR;

  552. }

  553. 

  554. 

  555. /**

  556.  *  Decode a vector-quantized cell.

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

  558.  *  with which a cell can be encoded.

  559.  *

  560.  *  @param ctx      pointer to the decoder context

  561.  *  @param avctx    ptr to the AVCodecContext

  562.  *  @param plane    pointer to the plane descriptor

  563.  *  @param cell     pointer to the cell  descriptor

  564.  *  @param data_ptr pointer to the compressed data

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

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

  567.  */

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

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

  570.                        const uint8_t *last_ptr)

  571. {

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

  573.     int           zoom_fac;

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

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

  576.     const vqEntry *delta[2];

  577.     const uint8_t *data_start = data_ptr;

  578. 

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

  580.     code     = *data_ptr++;

  581.     mode     = code >> 4;

  582.     vq_index = code & 0xF;

  583. 

  584.     /* setup output and reference pointers */

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

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

  587. 

  588.     if (cell->mv_ptr) {

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

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

  591.         if (   mv_x + 4*cell->xpos < 0

  592.             || mv_y + 4*cell->ypos < 0

  593.             || mv_x + 4*cell->xpos + 4*cell->width  > plane->width

  594.             || mv_y + 4*cell->ypos + 4*cell->height > plane->height) {

  595.             av_log(avctx, AV_LOG_ERROR, "motion vector %d %d outside reference\n", mv_x + 4*cell->xpos, mv_y + 4*cell->ypos);

  596.             return AVERROR_INVALIDDATA;

  597.         }

  598.     }

  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.         copy_cell(ctx, plane, cell);

  607.     } else {

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

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

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

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

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

  613.     }

  614. 

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

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

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

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

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

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

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

  622.     } else {

  623.         vq_index += ctx->cb_offset;

  624.         prim_indx = second_indx = vq_index;

  625.     }

  626. 

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

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

  629.                prim_indx, second_indx);

  630.         return AVERROR_INVALIDDATA;

  631.     }

  632. 

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

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

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

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

  637. 

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

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

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

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

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

  643.     }

  644. 

  645.     error = IV3_NOERR;

  646. 

  647.     switch (mode) {

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

  649.     case 1:

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

  651.     case 4:

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

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

  654.             return AVERROR_INVALIDDATA;

  655.         }

  656. 

  657.         zoom_fac = mode >= 3;

  658.         error = decode_cell_data(cell, block, ref_block, plane->pitch, 0, zoom_fac,

  659.                                  mode, delta, swap_quads, &data_ptr, last_ptr);

  660.         break;

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

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

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

  664.             error = decode_cell_data(cell, block, ref_block, plane->pitch, 1, 1,

  665.                                      mode, delta, swap_quads, &data_ptr, last_ptr);

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

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

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

  669.                return AVERROR_INVALIDDATA;

  670.             }

  671. 

  672.             zoom_fac = mode == 10;

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

  674.                                      zoom_fac, 1, mode, delta, swap_quads,

  675.                                      &data_ptr, last_ptr);

  676.         }

  677.         break;

  678.     default:

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

  680.         return AVERROR_INVALIDDATA;

  681.     }//switch mode

  682. 

  683.     switch (error) {

  684.     case IV3_BAD_RLE:

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

  686.                mode, data_ptr[-1]);

  687.         return AVERROR_INVALIDDATA;

  688.     case IV3_BAD_DATA:

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

  690.         return AVERROR_INVALIDDATA;

  691.     case IV3_BAD_COUNTER:

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

  693.         return AVERROR_INVALIDDATA;

  694.     case IV3_UNSUPPORTED:

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

  696.         return AVERROR_INVALIDDATA;

  697.     case IV3_OUT_OF_DATA:

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

  699.         return AVERROR_INVALIDDATA;

  700.     }

  701. 

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

  703. }

  704. 

  705. 

  706. /* Binary tree codes. */

  707. enum {

  708.     H_SPLIT    = 0,

  709.     V_SPLIT    = 1,

  710.     INTRA_NULL = 2,

  711.     INTER_DATA = 3

  712. };

  713. 

  714. 

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

  716. 

  717. #define UPDATE_BITPOS(n) \

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

  719.     ctx->need_resync = 1

  720. 

  721. #define RESYNC_BITSTREAM \

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

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

  724.         ctx->skip_bits   = 0;                                  \

  725.         ctx->need_resync = 0;                                  \

  726.     }

  727. 

  728. #define CHECK_CELL \

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

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

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

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

  733.         return AVERROR_INVALIDDATA;                                                              \

  734.     }

  735. 

  736. 

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

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

  739.                          const int depth, const int strip_width)

  740. {

  741.     Cell    curr_cell;

  742.     int     bytes_used;

  743.     int mv_x, mv_y;

  744. 

  745.     if (depth <= 0) {

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

  747.         return AVERROR_INVALIDDATA; // unwind recursion

  748.     }

  749. 

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

  751.     if (code == H_SPLIT) {

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

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

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

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

  756.             return AVERROR_INVALIDDATA;

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

  758.         if (curr_cell.width > strip_width) {

  759.             /* split strip */

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

  761.         } else

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

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

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

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

  766.             return AVERROR_INVALIDDATA;

  767.     }

  768. 

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

  770.         RESYNC_BITSTREAM;

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

  772.         case H_SPLIT:

  773.         case V_SPLIT:

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

  775.                 return AVERROR_INVALIDDATA;

  776.             break;

  777.         case INTRA_NULL:

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

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

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

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

  782.                 RESYNC_BITSTREAM;

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

  784.                 if (code >= 2) {

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

  786.                     return AVERROR_INVALIDDATA;

  787.                 }

  788.                 if (code == 1)

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

  790. 

  791.                 CHECK_CELL

  792.                 if (!curr_cell.mv_ptr)

  793.                     return AVERROR_INVALIDDATA;

  794. 

  795.                 mv_y = curr_cell.mv_ptr[0];

  796.                 mv_x = curr_cell.mv_ptr[1];

  797.                 if (   mv_x + 4*curr_cell.xpos < 0

  798.                     || mv_y + 4*curr_cell.ypos < 0

  799.                     || mv_x + 4*curr_cell.xpos + 4*curr_cell.width  > plane->width

  800.                     || mv_y + 4*curr_cell.ypos + 4*curr_cell.height > plane->height) {

  801.                     av_log(avctx, AV_LOG_ERROR, "motion vector %d %d outside reference\n", mv_x + 4*curr_cell.xpos, mv_y + 4*curr_cell.ypos);

  802.                     return AVERROR_INVALIDDATA;

  803.                 }

  804. 

  805.                 copy_cell(ctx, plane, &curr_cell);

  806.                 return 0;

  807.             }

  808.             break;

  809.         case INTER_DATA:

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

  811.                 unsigned mv_idx;

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

  813.                 if (!ctx->need_resync)

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

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

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

  817.                     return AVERROR_INVALIDDATA;

  818.                 }

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

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

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

  822.                     return AVERROR_INVALIDDATA;

  823.                 }

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

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

  826.                 UPDATE_BITPOS(8);

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

  828.                 if (!ctx->need_resync)

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

  830. 

  831.                 CHECK_CELL

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

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

  834.                 if (bytes_used < 0)

  835.                     return AVERROR_INVALIDDATA;

  836. 

  837.                 UPDATE_BITPOS(bytes_used << 3);

  838.                 ctx->next_cell_data += bytes_used;

  839.                 return 0;

  840.             }

  841.             break;

  842.         }

  843.     }//while

  844. 

  845.     return AVERROR_INVALIDDATA;

  846. }

  847. 

  848. 

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

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

  851.                         int32_t strip_width)

  852. {

  853.     Cell            curr_cell;

  854.     unsigned        num_vectors;

  855. 

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

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

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

  859.     if (num_vectors > 256) {

  860.         av_log(ctx->avctx, AV_LOG_ERROR,

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

  862.         return AVERROR_INVALIDDATA;

  863.     }

  864.     if (num_vectors * 2 > data_size)

  865.         return AVERROR_INVALIDDATA;

  866. 

  867.     ctx->num_vectors = num_vectors;

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

  869. 

  870.     /* init the bitreader */

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

  872.     ctx->skip_bits   = 0;

  873.     ctx->need_resync = 0;

  874. 

  875.     ctx->last_byte = data + data_size;

  876. 

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

  878.     curr_cell.xpos   = curr_cell.ypos = 0;

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

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

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

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

  883. 

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

  885. }

  886. 

  887. 

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

  889. 

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

  891.                                 const uint8_t *buf, int buf_size)

  892. {

  893.     const uint8_t   *buf_ptr = buf, *bs_hdr;

  894.     uint32_t        frame_num, word2, check_sum, data_size;

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

  896.     uint16_t        height, width;

  897.     int             i, j;

  898. 

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

  900.     frame_num = bytestream_get_le32(&buf_ptr);

  901.     word2     = bytestream_get_le32(&buf_ptr);

  902.     check_sum = bytestream_get_le32(&buf_ptr);

  903.     data_size = bytestream_get_le32(&buf_ptr);

  904. 

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

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

  907.         return AVERROR_INVALIDDATA;

  908.     }

  909. 

  910.     /* parse the bitstream header */

  911.     bs_hdr = buf_ptr;

  912.     buf_size -= 16;

  913. 

  914.     if (bytestream_get_le16(&buf_ptr) != 32) {

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

  916.         return AVERROR_INVALIDDATA;

  917.     }

  918. 

  919.     ctx->frame_num   =  frame_num;

  920.     ctx->frame_flags =  bytestream_get_le16(&buf_ptr);

  921.     ctx->data_size   = (bytestream_get_le32(&buf_ptr) + 7) >> 3;

  922.     ctx->cb_offset   = *buf_ptr++;

  923. 

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

  925.         return 4;

  926.     if (ctx->data_size > buf_size)

  927.         ctx->data_size = buf_size;

  928. 

  929.     buf_ptr += 3; // skip reserved byte and checksum

  930. 

  931.     /* check frame dimensions */

  932.     height = bytestream_get_le16(&buf_ptr);

  933.     width  = bytestream_get_le16(&buf_ptr);

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

  935.         return AVERROR_INVALIDDATA;

  936. 

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

  938.         int res;

  939. 

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

  941. 

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

  943.             height < 16 || height > 480 ||

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

  945.             av_log(avctx, AV_LOG_ERROR,

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

  947.             return AVERROR_INVALIDDATA;

  948.         }

  949.         free_frame_buffers(ctx);

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

  951.              return res;

  952.         avcodec_set_dimensions(avctx, width, height);

  953.     }

  954. 

  955.     y_offset = bytestream_get_le32(&buf_ptr);

  956.     v_offset = bytestream_get_le32(&buf_ptr);

  957.     u_offset = bytestream_get_le32(&buf_ptr);

  958. 

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

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

  961.     starts[0] = y_offset;

  962.     starts[1] = v_offset;

  963.     starts[2] = u_offset;

  964. 

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

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

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

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

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

  970.     }

  971. 

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

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

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

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

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

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

  978.         return AVERROR_INVALIDDATA;

  979.     }

  980. 

  981.     ctx->y_data_ptr = bs_hdr + y_offset;

  982.     ctx->v_data_ptr = bs_hdr + v_offset;

  983.     ctx->u_data_ptr = bs_hdr + u_offset;

  984.     ctx->alt_quant  = buf_ptr + sizeof(uint32_t);

  985. 

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

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

  988.         return 16;

  989.     }

  990. 

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

  992.         av_log_ask_for_sample(avctx, "8-bit pixel format\n");

  993.         return AVERROR_PATCHWELCOME;

  994.     }

  995. 

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

  997.         av_log_ask_for_sample(avctx, "halfpel motion vectors\n");

  998.         return AVERROR_PATCHWELCOME;

  999.     }

  1000. 

  1001.     return 0;

  1002. }

  1003. 

  1004. 

  1005. /**

  1006.  *  Convert and output the current plane.

  1007.  *  All pixel values will be upsampled by shifting right by one bit.

  1008.  *

  1009.  *  @param[in]  plane        pointer to the descriptor of the plane being processed

  1010.  *  @param[in]  buf_sel      indicates which frame buffer the input data stored in

  1011.  *  @param[out] dst          pointer to the buffer receiving converted pixels

  1012.  *  @param[in]  dst_pitch    pitch for moving to the next y line

  1013.  */

  1014. static void output_plane(const Plane *plane, int buf_sel, uint8_t *dst, int dst_pitch)

  1015. {

  1016.     int             x,y;

  1017.     const uint8_t   *src  = plane->pixels[buf_sel];

  1018.     uint32_t        pitch = plane->pitch;

  1019. 

  1020.     for (y = 0; y < plane->height; y++) {

  1021.         /* convert four pixels at once using SWAR */

  1022.         for (x = 0; x < plane->width >> 2; x++) {

  1023.             AV_WN32A(dst, (AV_RN32A(src) & 0x7F7F7F7F) << 1);

  1024.             src += 4;

  1025.             dst += 4;

  1026.         }

  1027. 

  1028.         for (x <<= 2; x < plane->width; x++)

  1029.             *dst++ = *src++ << 1;

  1030. 

  1031.         src += pitch     - plane->width;

  1032.         dst += dst_pitch - plane->width;

  1033.     }

  1034. }

  1035. 

  1036. 

  1037. static av_cold int decode_init(AVCodecContext *avctx)

  1038. {

  1039.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1040. 

  1041.     ctx->avctx     = avctx;

  1042.     avctx->pix_fmt = PIX_FMT_YUV410P;

  1043.     avcodec_get_frame_defaults(&ctx->frame);

  1044. 

  1045.     build_requant_tab();

  1046. 

  1047.     ff_dsputil_init(&ctx->dsp, avctx);

  1048. 

  1049.     return allocate_frame_buffers(ctx, avctx, avctx->width, avctx->height);

  1050. }

  1051. 

  1052. 

  1053. static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,

  1054.                         AVPacket *avpkt)

  1055. {

  1056.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1057.     const uint8_t *buf = avpkt->data;

  1058.     int buf_size       = avpkt->size;

  1059.     int res;

  1060. 

  1061.     res = decode_frame_headers(ctx, avctx, buf, buf_size);

  1062.     if (res < 0)

  1063.         return res;

  1064. 

  1065.     /* skip sync(null) frames */

  1066.     if (res) {

  1067.         // we have processed 16 bytes but no data was decoded

  1068.         *data_size = 0;

  1069.         return buf_size;

  1070.     }

  1071. 

  1072.     /* skip droppable INTER frames if requested */

  1073.     if (ctx->frame_flags & BS_NONREF &&

  1074.        (avctx->skip_frame >= AVDISCARD_NONREF))

  1075.         return 0;

  1076. 

  1077.     /* skip INTER frames if requested */

  1078.     if (!(ctx->frame_flags & BS_KEYFRAME) && avctx->skip_frame >= AVDISCARD_NONKEY)

  1079.         return 0;

  1080. 

  1081.     /* use BS_BUFFER flag for buffer switching */

  1082.     ctx->buf_sel = (ctx->frame_flags >> BS_BUFFER) & 1;

  1083. 

  1084.     /* decode luma plane */

  1085.     if ((res = decode_plane(ctx, avctx, ctx->planes, ctx->y_data_ptr, ctx->y_data_size, 40)))

  1086.         return res;

  1087. 

  1088.     /* decode chroma planes */

  1089.     if ((res = decode_plane(ctx, avctx, &ctx->planes[1], ctx->u_data_ptr, ctx->u_data_size, 10)))

  1090.         return res;

  1091. 

  1092.     if ((res = decode_plane(ctx, avctx, &ctx->planes[2], ctx->v_data_ptr, ctx->v_data_size, 10)))

  1093.         return res;

  1094. 

  1095.     if (ctx->frame.data[0])

  1096.         avctx->release_buffer(avctx, &ctx->frame);

  1097. 

  1098.     ctx->frame.reference = 0;

  1099.     if ((res = avctx->get_buffer(avctx, &ctx->frame)) < 0) {

  1100.         av_log(ctx->avctx, AV_LOG_ERROR, "get_buffer() failed\n");

  1101.         return res;

  1102.     }

  1103. 

  1104.     output_plane(&ctx->planes[0], ctx->buf_sel, ctx->frame.data[0], ctx->frame.linesize[0]);

  1105.     output_plane(&ctx->planes[1], ctx->buf_sel, ctx->frame.data[1], ctx->frame.linesize[1]);

  1106.     output_plane(&ctx->planes[2], ctx->buf_sel, ctx->frame.data[2], ctx->frame.linesize[2]);

  1107. 

  1108.     *data_size      = sizeof(AVFrame);

  1109.     *(AVFrame*)data = ctx->frame;

  1110. 

  1111.     return buf_size;

  1112. }

  1113. 

  1114. 

  1115. static av_cold int decode_close(AVCodecContext *avctx)

  1116. {

  1117.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1118. 

  1119.     free_frame_buffers(avctx->priv_data);

  1120. 

  1121.     if (ctx->frame.data[0])

  1122.         avctx->release_buffer(avctx, &ctx->frame);

  1123. 

  1124.     return 0;

  1125. }

  1126. 

  1127. AVCodec ff_indeo3_decoder = {

  1128.     .name           = "indeo3",

  1129.     .type           = AVMEDIA_TYPE_VIDEO,

  1130.     .id             = AV_CODEC_ID_INDEO3,

  1131.     .priv_data_size = sizeof(Indeo3DecodeContext),

  1132.     .init           = decode_init,

  1133.     .close          = decode_close,

  1134.     .decode         = decode_frame,

  1135.     .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo 3"),

  1136. };