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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 Libav.

  6.  *

  7.  * Libav 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.  * Libav 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 Libav; 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. 

  35. #include "avcodec.h"

  36. #include "bitstream.h"

  37. #include "bytestream.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) ///< 8-bit 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.     ptrdiff_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.     BitstreamContext bc;

  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 const int8_t offsets[8] = { 1, 1, 2, -3, -3, 3, 4, 4 };

  122.     static const 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)

  153. {

  154.     int p, luma_width, luma_height, chroma_width, chroma_height;

  155.     int luma_size, chroma_size;

  156.     ptrdiff_t luma_pitch, chroma_pitch;

  157. 

  158.     luma_width  = ctx->width;

  159.     luma_height = ctx->height;

  160. 

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

  162.         luma_height < 16 || luma_height > 480 ||

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

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

  165.                luma_width, luma_height);

  166.         return AVERROR_INVALIDDATA;

  167.     }

  168. 

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

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

  171. 

  172.     luma_pitch   = FFALIGN(luma_width,   16);

  173.     chroma_pitch = FFALIGN(chroma_width, 16);

  174. 

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

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

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

  178. 

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

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

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

  182. 

  183.     /* allocate frame buffers */

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

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

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

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

  188. 

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

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

  191. 

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

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

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

  195. 

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

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

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

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

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

  201.     }

  202. 

  203.     return 0;

  204. }

  205. 

  206. 

  207. static av_cold void free_frame_buffers(Indeo3DecodeContext *ctx)

  208. {

  209.     int p;

  210. 

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

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

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

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

  215.     }

  216. }

  217. 

  218. 

  219. /**

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

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

  222.  *

  223.  *  @param ctx      pointer to the decoder context

  224.  *  @param plane    pointer to the plane descriptor

  225.  *  @param cell     pointer to the cell  descriptor

  226.  */

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

  228. {

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

  230.     uint8_t *src, *dst;

  231. 

  232.     /* setup output and reference pointers */

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

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

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

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

  237. 

  238.     /* -1 because there is an extra line on top for prediction */

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

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

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

  242.         av_log(ctx->avctx, AV_LOG_ERROR,

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

  244.         return AVERROR_INVALIDDATA;

  245.     }

  246. 

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

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

  249. 

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

  251. 

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

  253.         /* copy using 16xH blocks */

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

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

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

  257.         }

  258. 

  259.         /* copy using 8xH blocks */

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

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

  262.             w -= 2;

  263.             src += 8;

  264.             dst += 8;

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

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

  267.             w--;

  268.             src += 4;

  269.             dst += 4;

  270.         }

  271.     }

  272. 

  273.     return 0;

  274. }

  275. 

  276. 

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

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

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

  280. 

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

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

  283. 

  284. 

  285. /*

  286.  *  Replicate each even pixel as follows:

  287.  *  ABCDEFGH -> AACCEEGG

  288.  */

  289. static inline uint64_t replicate64(uint64_t a) {

  290. #if HAVE_BIGENDIAN

  291.     a &= 0xFF00FF00FF00FF00ULL;

  292.     a |= a >> 8;

  293. #else

  294.     a &= 0x00FF00FF00FF00FFULL;

  295.     a |= a << 8;

  296. #endif

  297.     return a;

  298. }

  299. 

  300. static inline uint32_t replicate32(uint32_t a) {

  301. #if HAVE_BIGENDIAN

  302.     a &= 0xFF00FF00UL;

  303.     a |= a >> 8;

  304. #else

  305.     a &= 0x00FF00FFUL;

  306.     a |= a << 8;

  307. #endif

  308.     return a;

  309. }

  310. 

  311. 

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

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

  314.                            int32_t row_offset)

  315. {

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

  317.         AV_WN64A(dst, pix);

  318. }

  319. 

  320. 

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

  322. enum {

  323.     IV3_NOERR       = 0,

  324.     IV3_BAD_RLE     = 1,

  325.     IV3_BAD_DATA    = 2,

  326.     IV3_BAD_COUNTER = 3,

  327.     IV3_UNSUPPORTED = 4,

  328.     IV3_OUT_OF_DATA = 5

  329. };

  330. 

  331. 

  332. #define BUFFER_PRECHECK \

  333. if (*data_ptr >= last_ptr) \

  334.     return IV3_OUT_OF_DATA; \

  335. 

  336. #define RLE_BLOCK_COPY \

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

  338.         ctx->hdsp.put_pixels_tab[2][0](dst, ref, row_offset, 4 << v_zoom)

  339. 

  340. #define RLE_BLOCK_COPY_8 \

  341.     pix64 = AV_RN64(ref);\

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

  343.         pix64 = replicate64(pix64);\

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

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

  346.     } else \

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

  348. 

  349. #define RLE_LINES_COPY \

  350.     ctx->hdsp.put_pixels_tab[2][0](dst, ref, row_offset, num_lines << v_zoom)

  351. 

  352. #define RLE_LINES_COPY_M10 \

  353.     pix64 = AV_RN64(ref);\

  354.     if (is_top_of_cell) {\

  355.         pix64 = replicate64(pix64);\

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

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

  358.     } else \

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

  360. 

  361. #define APPLY_DELTA_4 \

  362.     AV_WN16A(dst + line_offset    ,\

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

  364.     AV_WN16A(dst + line_offset + 2,\

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

  366.     if (mode >= 3) {\

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

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

  369.         } else {\

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

  371.         }\

  372.     }

  373. 

  374. #define APPLY_DELTA_8 \

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

  376.     if (is_top_of_cell) { \

  377.         AV_WN32A(dst + row_offset    , \

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

  379.         AV_WN32A(dst + row_offset + 4, \

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

  381.     } else { \

  382.         AV_WN32A(dst + row_offset    , \

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

  384.         AV_WN32A(dst + row_offset + 4, \

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

  386.     } \

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

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

  389.     /* otherwise - interpolate */\

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

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

  392.     } else \

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

  394. 

  395. 

  396. #define APPLY_DELTA_1011_INTER \

  397.     if (mode == 10) { \

  398.         AV_WN32A(dst                 , \

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

  400.         AV_WN32A(dst + 4             , \

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

  402.         AV_WN32A(dst + row_offset    , \

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

  404.         AV_WN32A(dst + row_offset + 4, \

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

  406.     } else { \

  407.         AV_WN16A(dst                 , \

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

  409.         AV_WN16A(dst + 2             , \

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

  411.         AV_WN16A(dst + row_offset    , \

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

  413.         AV_WN16A(dst + row_offset + 2, \

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

  415.     }

  416. 

  417. 

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

  419.                             uint8_t *block, uint8_t *ref_block,

  420.                             ptrdiff_t row_offset, int h_zoom, int v_zoom, int mode,

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

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

  423. {

  424.     int           x, y, line, num_lines;

  425.     int           rle_blocks = 0;

  426.     uint8_t       code, *dst, *ref;

  427.     const vqEntry *delta_tab;

  428.     unsigned int  dyad1, dyad2;

  429.     uint64_t      pix64;

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

  431.     int           blk_row_offset, line_offset;

  432. 

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

  434.     line_offset    = v_zoom ? row_offset : 0;

  435. 

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

  437.         return IV3_BAD_DATA;

  438. 

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

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

  441.             ref = ref_block;

  442.             dst = block;

  443. 

  444.             if (rle_blocks > 0) {

  445.                 if (mode <= 4) {

  446.                     RLE_BLOCK_COPY;

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

  448.                     RLE_BLOCK_COPY_8;

  449.                 }

  450.                 rle_blocks--;

  451.             } else {

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

  453.                     num_lines = 1;

  454.                     is_top_of_cell = is_first_row && !line;

  455. 

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

  457.                     if (mode <= 4)

  458.                         delta_tab = delta[line & 1];

  459.                     else

  460.                         delta_tab = delta[1];

  461.                     BUFFER_PRECHECK;

  462.                     code = bytestream_get_byte(data_ptr);

  463.                     if (code < 248) {

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

  465.                             BUFFER_PRECHECK;

  466.                             dyad1 = bytestream_get_byte(data_ptr);

  467.                             dyad2 = code;

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

  469.                                 return IV3_BAD_DATA;

  470.                         } else {

  471.                             /* process QUADS */

  472.                             code -= delta_tab->num_dyads;

  473.                             dyad1 = code / delta_tab->quad_exp;

  474.                             dyad2 = code % delta_tab->quad_exp;

  475.                             if (swap_quads[line & 1])

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

  477.                         }

  478.                         if (mode <= 4) {

  479.                             APPLY_DELTA_4;

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

  481.                             APPLY_DELTA_8;

  482.                         } else {

  483.                             APPLY_DELTA_1011_INTER;

  484.                         }

  485.                     } else {

  486.                         /* process RLE codes */

  487.                         switch (code) {

  488.                         case RLE_ESC_FC:

  489.                             skip_flag  = 0;

  490.                             rle_blocks = 1;

  491.                             code       = 253;

  492.                             /* FALLTHROUGH */

  493.                         case RLE_ESC_FF:

  494.                         case RLE_ESC_FE:

  495.                         case RLE_ESC_FD:

  496.                             num_lines = 257 - code - line;

  497.                             if (num_lines <= 0)

  498.                                 return IV3_BAD_RLE;

  499.                             if (mode <= 4) {

  500.                                 RLE_LINES_COPY;

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

  502.                                 RLE_LINES_COPY_M10;

  503.                             }

  504.                             break;

  505.                         case RLE_ESC_FB:

  506.                             BUFFER_PRECHECK;

  507.                             code = bytestream_get_byte(data_ptr);

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

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

  510.                                 return IV3_BAD_COUNTER;

  511.                             skip_flag = code & 0x20;

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

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

  514.                                 if (mode <= 4) {

  515.                                     RLE_LINES_COPY;

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

  517.                                     RLE_LINES_COPY_M10;

  518.                                 }

  519.                             }

  520.                             break;

  521.                         case RLE_ESC_F9:

  522.                             skip_flag  = 1;

  523.                             rle_blocks = 1;

  524.                             /* FALLTHROUGH */

  525.                         case RLE_ESC_FA:

  526.                             if (line)

  527.                                 return IV3_BAD_RLE;

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

  529.                             if (cell->mv_ptr) {

  530.                                 if (mode <= 4) {

  531.                                     RLE_LINES_COPY;

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

  533.                                     RLE_LINES_COPY_M10;

  534.                                 }

  535.                             }

  536.                             break;

  537.                         default:

  538.                             return IV3_UNSUPPORTED;

  539.                         }

  540.                     }

  541. 

  542.                     line += num_lines;

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

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

  545.                 }

  546.             }

  547. 

  548.             /* move to next horizontal block */

  549.             block     += 4 << h_zoom;

  550.             ref_block += 4 << h_zoom;

  551.         }

  552. 

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

  554.         ref_block += blk_row_offset;

  555.         block     += blk_row_offset;

  556.     }

  557.     return IV3_NOERR;

  558. }

  559. 

  560. 

  561. /**

  562.  *  Decode a vector-quantized cell.

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

  564.  *  with which a cell can be encoded.

  565.  *

  566.  *  @param ctx      pointer to the decoder context

  567.  *  @param avctx    ptr to the AVCodecContext

  568.  *  @param plane    pointer to the plane descriptor

  569.  *  @param cell     pointer to the cell  descriptor

  570.  *  @param data_ptr pointer to the compressed data

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

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

  573.  */

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

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

  576.                        const uint8_t *last_ptr)

  577. {

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

  579.     int           zoom_fac;

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

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

  582.     const vqEntry *delta[2];

  583.     const uint8_t *data_start = data_ptr;

  584. 

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

  586.     code     = *data_ptr++;

  587.     mode     = code >> 4;

  588.     vq_index = code & 0xF;

  589. 

  590.     /* setup output and reference pointers */

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

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

  593.     if (!cell->mv_ptr) {

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

  595.         ref_block = block - plane->pitch;

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

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

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

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

  600.         if (ret < 0)

  601.             return ret;

  602.     } else {

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

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

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

  606. 

  607.         /* -1 because there is an extra line on top for prediction */

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

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

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

  611.             av_log(ctx->avctx, AV_LOG_ERROR,

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

  613.             return AVERROR_INVALIDDATA;

  614.         }

  615. 

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

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

  618.     }

  619. 

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

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

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

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

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

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

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

  627.     } else {

  628.         vq_index += ctx->cb_offset;

  629.         prim_indx = second_indx = vq_index;

  630.     }

  631. 

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

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

  634.                prim_indx, second_indx);

  635.         return AVERROR_INVALIDDATA;

  636.     }

  637. 

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

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

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

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

  642. 

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

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

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

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

  647.             ref_block[x] = requant_tab[vq_index & 7][ref_block[x]];

  648.     }

  649. 

  650.     error = IV3_NOERR;

  651. 

  652.     switch (mode) {

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

  654.     case 1:

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

  656.     case 4:

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

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

  659.             return AVERROR_INVALIDDATA;

  660.         }

  661. 

  662.         zoom_fac = mode >= 3;

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

  664.                                  0, zoom_fac, mode, delta, swap_quads,

  665.                                  &data_ptr, last_ptr);

  666.         break;

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

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

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

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

  671.                                      1, 1, mode, delta, swap_quads,

  672.                                      &data_ptr, last_ptr);

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

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

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

  676.                return AVERROR_INVALIDDATA;

  677.             }

  678. 

  679.             zoom_fac = mode == 10;

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

  681.                                      zoom_fac, 1, mode, delta, swap_quads,

  682.                                      &data_ptr, last_ptr);

  683.         }

  684.         break;

  685.     default:

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

  687.         return AVERROR_INVALIDDATA;

  688.     }//switch mode

  689. 

  690.     switch (error) {

  691.     case IV3_BAD_RLE:

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

  693.                mode, data_ptr[-1]);

  694.         return AVERROR_INVALIDDATA;

  695.     case IV3_BAD_DATA:

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

  697.         return AVERROR_INVALIDDATA;

  698.     case IV3_BAD_COUNTER:

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

  700.         return AVERROR_INVALIDDATA;

  701.     case IV3_UNSUPPORTED:

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

  703.         return AVERROR_INVALIDDATA;

  704.     case IV3_OUT_OF_DATA:

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

  706.         return AVERROR_INVALIDDATA;

  707.     }

  708. 

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

  710. }

  711. 

  712. 

  713. /* Binary tree codes. */

  714. enum {

  715.     H_SPLIT    = 0,

  716.     V_SPLIT    = 1,

  717.     INTRA_NULL = 2,

  718.     INTER_DATA = 3

  719. };

  720. 

  721. 

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

  723. 

  724. #define UPDATE_BITPOS(n) \

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

  726.     ctx->need_resync = 1

  727. 

  728. #define RESYNC_BITSTREAM \

  729.     if (ctx->need_resync && !(bitstream_tell(&ctx->bc) & 7)) { \

  730.         bitstream_skip(&ctx->bc, ctx->skip_bits);              \

  731.         ctx->skip_bits   = 0;                                  \

  732.         ctx->need_resync = 0;                                  \

  733.     }

  734. 

  735. #define CHECK_CELL \

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

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

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

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

  740.         return AVERROR_INVALIDDATA;                                                              \

  741.     }

  742. 

  743. 

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

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

  746.                          const int depth, const int strip_width)

  747. {

  748.     Cell    curr_cell;

  749.     int     bytes_used, ret;

  750. 

  751.     if (depth <= 0) {

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

  753.         return AVERROR_INVALIDDATA; // unwind recursion

  754.     }

  755. 

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

  757.     if (code == H_SPLIT) {

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

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

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

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

  762.             return AVERROR_INVALIDDATA;

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

  764.         if (curr_cell.width > strip_width) {

  765.             /* split strip */

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

  767.         } else

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

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

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

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

  772.             return AVERROR_INVALIDDATA;

  773.     }

  774. 

  775.     while (1) { /* loop until return */

  776.         RESYNC_BITSTREAM;

  777.         switch (code = bitstream_read(&ctx->bc, 2)) {

  778.         case H_SPLIT:

  779.         case V_SPLIT:

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

  781.                 return AVERROR_INVALIDDATA;

  782.             break;

  783.         case INTRA_NULL:

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

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

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

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

  788.                 RESYNC_BITSTREAM;

  789.                 code = bitstream_read(&ctx->bc, 2);

  790.                 if (code >= 2) {

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

  792.                     return AVERROR_INVALIDDATA;

  793.                 }

  794.                 if (code == 1)

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

  796. 

  797.                 CHECK_CELL

  798.                 if (!curr_cell.mv_ptr)

  799.                     return AVERROR_INVALIDDATA;

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

  801.                 return ret;

  802.             }

  803.             break;

  804.         case INTER_DATA:

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

  806.                 unsigned mv_idx;

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

  808.                 if (!ctx->need_resync)

  809.                     ctx->next_cell_data = &ctx->bc.buffer[(bitstream_tell(&ctx->bc) + 7) >> 3];

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

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

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

  813.                     return AVERROR_INVALIDDATA;

  814.                 }

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

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

  817.                 UPDATE_BITPOS(8);

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

  819.                 if (!ctx->need_resync)

  820.                     ctx->next_cell_data = &ctx->bc.buffer[(bitstream_tell(&ctx->bc) + 7) >> 3];

  821. 

  822.                 CHECK_CELL

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

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

  825.                 if (bytes_used < 0)

  826.                     return AVERROR_INVALIDDATA;

  827. 

  828.                 UPDATE_BITPOS(bytes_used << 3);

  829.                 ctx->next_cell_data += bytes_used;

  830.                 return 0;

  831.             }

  832.             break;

  833.         }

  834.     }//while

  835. }

  836. 

  837. 

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

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

  840.                         int32_t strip_width)

  841. {

  842.     Cell            curr_cell;

  843.     unsigned        num_vectors;

  844. 

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

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

  847.     num_vectors = bytestream_get_le32(&data);

  848.     if (num_vectors > 256) {

  849.         av_log(ctx->avctx, AV_LOG_ERROR,

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

  851.         return AVERROR_INVALIDDATA;

  852.     }

  853.     if (num_vectors * 2 >= data_size)

  854.         return AVERROR_INVALIDDATA;

  855. 

  856.     ctx->num_vectors = num_vectors;

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

  858. 

  859.     /* init the bitreader */

  860.     bitstream_init8(&ctx->bc, &data[num_vectors * 2], data_size - num_vectors * 2);

  861.     ctx->skip_bits   = 0;

  862.     ctx->need_resync = 0;

  863. 

  864.     ctx->last_byte = data + data_size - 1;

  865. 

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

  867.     curr_cell.xpos   = curr_cell.ypos = 0;

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

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

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

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

  872. 

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

  874. }

  875. 

  876. 

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

  878. 

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

  880.                                 const uint8_t *buf, int buf_size)

  881. {

  882.     GetByteContext gb;

  883.     const uint8_t   *bs_hdr;

  884.     uint32_t        frame_num, word2, check_sum, data_size;

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

  886.     uint16_t        height, width;

  887.     int             i, j;

  888. 

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

  890. 

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

  892.     frame_num = bytestream2_get_le32(&gb);

  893.     word2     = bytestream2_get_le32(&gb);

  894.     check_sum = bytestream2_get_le32(&gb);

  895.     data_size = bytestream2_get_le32(&gb);

  896. 

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

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

  899.         return AVERROR_INVALIDDATA;

  900.     }

  901. 

  902.     /* parse the bitstream header */

  903.     bs_hdr = gb.buffer;

  904. 

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

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

  907.         return AVERROR_INVALIDDATA;

  908.     }

  909. 

  910.     ctx->frame_num   =  frame_num;

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

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

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

  914. 

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

  916.         return 4;

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

  918. 

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

  920. 

  921.     /* check frame dimensions */

  922.     height = bytestream2_get_le16(&gb);

  923.     width  = bytestream2_get_le16(&gb);

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

  925.         return AVERROR_INVALIDDATA;

  926. 

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

  928.         int res;

  929. 

  930.         ff_dlog(avctx, "Frame dimensions changed!\n");

  931. 

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

  933.             height < 16 || height > 480 ||

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

  935.             av_log(avctx, AV_LOG_ERROR,

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

  937.             return AVERROR_INVALIDDATA;

  938.         }

  939. 

  940.         ctx->width  = width;

  941.         ctx->height = height;

  942. 

  943.         free_frame_buffers(ctx);

  944.         if ((res = allocate_frame_buffers(ctx, avctx)) < 0)

  945.              return res;

  946.         if ((res = ff_set_dimensions(avctx, width, height)) < 0)

  947.             return res;

  948.     }

  949. 

  950.     y_offset = bytestream2_get_le32(&gb);

  951.     v_offset = bytestream2_get_le32(&gb);

  952.     u_offset = bytestream2_get_le32(&gb);

  953.     bytestream2_skip(&gb, 4);

  954. 

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

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

  957.     starts[0] = y_offset;

  958.     starts[1] = v_offset;

  959.     starts[2] = u_offset;

  960. 

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

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

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

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

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

  966.     }

  967. 

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

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

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

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

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

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

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

  975.         return AVERROR_INVALIDDATA;

  976.     }

  977. 

  978.     ctx->y_data_ptr = bs_hdr + y_offset;

  979.     ctx->v_data_ptr = bs_hdr + v_offset;

  980.     ctx->u_data_ptr = bs_hdr + u_offset;

  981.     ctx->alt_quant  = gb.buffer;

  982. 

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

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

  985.         return 16;

  986.     }

  987. 

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

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

  990.         return AVERROR_PATCHWELCOME;

  991.     }

  992. 

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

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

  995.         return AVERROR_PATCHWELCOME;

  996.     }

  997. 

  998.     return 0;

  999. }

  1000. 

  1001. 

  1002. /**

  1003.  *  Convert and output the current plane.

  1004.  *  All pixel values will be upsampled by shifting right by one bit.

  1005.  *

  1006.  *  @param[in]  plane        pointer to the descriptor of the plane being processed

  1007.  *  @param[in]  buf_sel      indicates which frame buffer the input data stored in

  1008.  *  @param[out] dst          pointer to the buffer receiving converted pixels

  1009.  *  @param[in]  dst_pitch    pitch for moving to the next y line

  1010.  *  @param[in]  dst_height   output plane height

  1011.  */

  1012. static void output_plane(const Plane *plane, int buf_sel, uint8_t *dst,

  1013.                          ptrdiff_t dst_pitch, int dst_height)

  1014. {

  1015.     int             x,y;

  1016.     const uint8_t   *src  = plane->pixels[buf_sel];

  1017.     ptrdiff_t       pitch = plane->pitch;

  1018. 

  1019.     dst_height = FFMIN(dst_height, plane->height);

  1020.     for (y = 0; y < dst_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.     ctx->width     = avctx->width;

  1043.     ctx->height    = avctx->height;

  1044.     avctx->pix_fmt = AV_PIX_FMT_YUV410P;

  1045. 

  1046.     build_requant_tab();

  1047. 

  1048.     ff_hpeldsp_init(&ctx->hdsp, avctx->flags);

  1049. 

  1050.     allocate_frame_buffers(ctx, avctx);

  1051. 

  1052.     return 0;

  1053. }

  1054. 

  1055. 

  1056. static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

  1057.                         AVPacket *avpkt)

  1058. {

  1059.     Indeo3DecodeContext *ctx = avctx->priv_data;

  1060.     const uint8_t *buf = avpkt->data;

  1061.     int buf_size       = avpkt->size;

  1062.     AVFrame *frame     = data;

  1063.     int res;

  1064. 

  1065.     res = decode_frame_headers(ctx, avctx, buf, buf_size);

  1066.     if (res < 0)

  1067.         return res;

  1068. 

  1069.     /* skip sync(null) frames */

  1070.     if (res) {

  1071.         // we have processed 16 bytes but no data was decoded

  1072.         *got_frame = 0;

  1073.         return buf_size;

  1074.     }

  1075. 

  1076.     /* skip droppable INTER frames if requested */

  1077.     if (ctx->frame_flags & BS_NONREF &&

  1078.        (avctx->skip_frame >= AVDISCARD_NONREF))

  1079.         return 0;

  1080. 

  1081.     /* skip INTER frames if requested */

  1082.     if (!(ctx->frame_flags & BS_KEYFRAME) && avctx->skip_frame >= AVDISCARD_NONKEY)

  1083.         return 0;

  1084. 

  1085.     /* use BS_BUFFER flag for buffer switching */

  1086.     ctx->buf_sel = (ctx->frame_flags >> BS_BUFFER) & 1;

  1087. 

  1088.     /* decode luma plane */

  1089.     if ((res = decode_plane(ctx, avctx, ctx->planes, ctx->y_data_ptr, ctx->y_data_size, 40)))

  1090.         return res;

  1091. 

  1092.     /* decode chroma planes */

  1093.     if ((res = decode_plane(ctx, avctx, &ctx->planes[1], ctx->u_data_ptr, ctx->u_data_size, 10)))

  1094.         return res;

  1095. 

  1096.     if ((res = decode_plane(ctx, avctx, &ctx->planes[2], ctx->v_data_ptr, ctx->v_data_size, 10)))

  1097.         return res;

  1098. 

  1099.     if ((res = ff_get_buffer(avctx, frame, 0)) < 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,

  1105.                  frame->data[0], frame->linesize[0],

  1106.                  avctx->height);

  1107.     output_plane(&ctx->planes[1], ctx->buf_sel,

  1108.                  frame->data[1], frame->linesize[1],

  1109.                  (avctx->height + 3) >> 2);

  1110.     output_plane(&ctx->planes[2], ctx->buf_sel,

  1111.                  frame->data[2], frame->linesize[2],

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

  1113. 

  1114.     *got_frame = 1;

  1115. 

  1116.     return buf_size;

  1117. }

  1118. 

  1119. 

  1120. static av_cold int decode_close(AVCodecContext *avctx)

  1121. {

  1122.     free_frame_buffers(avctx->priv_data);

  1123. 

  1124.     return 0;

  1125. }

  1126. 

  1127. AVCodec ff_indeo3_decoder = {

  1128.     .name           = "indeo3",

  1129.     .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo 3"),

  1130.     .type           = AVMEDIA_TYPE_VIDEO,

  1131.     .id             = AV_CODEC_ID_INDEO3,

  1132.     .priv_data_size = sizeof(Indeo3DecodeContext),

  1133.     .init           = decode_init,

  1134.     .close          = decode_close,

  1135.     .decode         = decode_frame,

  1136.     .capabilities   = AV_CODEC_CAP_DR1,

  1137. };