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FFmpeg/libavcodec/smacker.c

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  1. /*

  2.  * Smacker decoder

  3.  * Copyright (c) 2006 Konstantin Shishkov

  4.  *

  5.  * This library is free software; you can redistribute it and/or

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

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

  8.  * version 2 of the License, or (at your option) any later version.

  9.  *

  10.  * This library is distributed in the hope that it will be useful,

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

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

  13.  * Lesser General Public License for more details.

  14.  *

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

  16.  * License along with this library; if not, write to the Free Software

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

  18.  *

  19.  */

  20. 

  21. /**

  22.  * @file smacker.c

  23.  * Smacker decoder

  24.  */

  25. 

  26. /*

  27.  * Based on http://wiki.multimedia.cx/index.php?title=Smacker

  28.  */

  29. 

  30. #include <stdio.h>

  31. #include <stdlib.h>

  32. 

  33. #include "common.h"

  34. #include "avcodec.h"

  35. 

  36. #define ALT_BITSTREAM_READER_LE

  37. #include "bitstream.h"

  38. 

  39. #define SMKTREE_BITS 9

  40. #define SMK_NODE 0x80000000

  41. 

  42. /*

  43.  * Decoder context

  44.  */

  45. typedef struct SmackVContext {

  46.     AVCodecContext *avctx;

  47.     AVFrame pic;

  48. 

  49.     int *mmap_tbl, *mclr_tbl, *full_tbl, *type_tbl;

  50.     int mmap_last[3], mclr_last[3], full_last[3], type_last[3];

  51. } SmackVContext;

  52. 

  53. /**

  54.  * Context used for code reconstructing

  55.  */

  56. typedef struct HuffContext {

  57.     int length;

  58.     int maxlength;

  59.     int current;

  60.     uint32_t *bits;

  61.     int *lengths;

  62.     int *values;

  63. } HuffContext;

  64. 

  65. /* common parameters used for decode_bigtree */

  66. typedef struct DBCtx {

  67.     VLC *v1, *v2;

  68.     int *recode1, *recode2;

  69.     int escapes[3];

  70.     int *last;

  71.     int lcur;

  72. } DBCtx;

  73. 

  74. /* possible runs of blocks */

  75. static const int block_runs[64] = {

  76.       1,    2,    3,    4,    5,    6,    7,    8,

  77.       9,   10,   11,   12,   13,   14,   15,   16,

  78.      17,   18,   19,   20,   21,   22,   23,   24,

  79.      25,   26,   27,   28,   29,   30,   31,   32,

  80.      33,   34,   35,   36,   37,   38,   39,   40,

  81.      41,   42,   43,   44,   45,   46,   47,   48,

  82.      49,   50,   51,   52,   53,   54,   55,   56,

  83.      57,   58,   59,  128,  256,  512, 1024, 2048 };

  84. 

  85. enum SmkBlockTypes {

  86.     SMK_BLK_MONO = 0,

  87.     SMK_BLK_FULL = 1,

  88.     SMK_BLK_SKIP = 2,

  89.     SMK_BLK_FILL = 3 };

  90. 

  91. /**

  92.  * Decode local frame tree

  93.  */

  94. static int smacker_decode_tree(GetBitContext *gb, HuffContext *hc, uint32_t prefix, int length)

  95. {

  96.     if(!get_bits1(gb)){ //Leaf

  97.         if(hc->current >= 256){

  98.             av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");

  99.             return -1;

  100.         }

  101.         if(length){

  102.             hc->bits[hc->current] = prefix;

  103.             hc->lengths[hc->current] = length;

  104.         } else {

  105.             hc->bits[hc->current] = 0;

  106.             hc->lengths[hc->current] = 0;

  107.         }

  108.         hc->values[hc->current] = get_bits(gb, 8);

  109.         hc->current++;

  110.         if(hc->maxlength < length)

  111.             hc->maxlength = length;

  112.         return 0;

  113.     } else { //Node

  114.         int r;

  115.         length++;

  116.         r = smacker_decode_tree(gb, hc, prefix, length);

  117.         if(r)

  118.             return r;

  119.         return smacker_decode_tree(gb, hc, prefix | (1 << (length - 1)), length);

  120.     }

  121. }

  122. 

  123. /**

  124.  * Decode header tree

  125.  */

  126. static int smacker_decode_bigtree(GetBitContext *gb, HuffContext *hc, DBCtx *ctx)

  127. {

  128.     if(!get_bits1(gb)){ //Leaf

  129.         int val, i1, i2, b1, b2;

  130.         if(hc->current >= hc->length){

  131.             av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");

  132.             return -1;

  133.         }

  134.         b1 = get_bits_count(gb);

  135.         i1 = get_vlc2(gb, ctx->v1->table, SMKTREE_BITS, 3);

  136.         b1 = get_bits_count(gb) - b1;

  137.         b2 = get_bits_count(gb);

  138.         i2 = get_vlc2(gb, ctx->v2->table, SMKTREE_BITS, 3);

  139.         b2 = get_bits_count(gb) - b2;

  140.         val = ctx->recode1[i1] | (ctx->recode2[i2] << 8);

  141.         if(val == ctx->escapes[0]) {

  142.             ctx->last[0] = hc->current;

  143.             val = 0;

  144.         } else if(val == ctx->escapes[1]) {

  145.             ctx->last[1] = hc->current;

  146.             val = 0;

  147.         } else if(val == ctx->escapes[2]) {

  148.             ctx->last[2] = hc->current;

  149.             val = 0;

  150.         }

  151. 

  152.         hc->values[hc->current++] = val;

  153.         return 1;

  154.     } else { //Node

  155.         int r = 0, t;

  156. 

  157.         t = hc->current++;

  158.         r = smacker_decode_bigtree(gb, hc, ctx);

  159.         if(r < 0)

  160.             return r;

  161.         hc->values[t] = SMK_NODE | r;

  162.         r++;

  163.         r += smacker_decode_bigtree(gb, hc, ctx);

  164.         return r;

  165.     }

  166. }

  167. 

  168. /**

  169.  * Store large tree as FFmpeg's vlc codes

  170.  */

  171. static int smacker_decode_header_tree(SmackVContext *smk, GetBitContext *gb, int **recodes, int *last, int size)

  172. {

  173.     int res;

  174.     HuffContext huff;

  175.     HuffContext tmp1, tmp2;

  176.     VLC vlc[2];

  177.     int escapes[3];

  178.     DBCtx ctx;

  179. 

  180.     tmp1.length = 256;

  181.     tmp1.maxlength = 0;

  182.     tmp1.current = 0;

  183.     tmp1.bits = av_mallocz(256 * 4);

  184.     tmp1.lengths = av_mallocz(256 * sizeof(int));

  185.     tmp1.values = av_mallocz(256 * sizeof(int));

  186. 

  187.     tmp2.length = 256;

  188.     tmp2.maxlength = 0;

  189.     tmp2.current = 0;

  190.     tmp2.bits = av_mallocz(256 * 4);

  191.     tmp2.lengths = av_mallocz(256 * sizeof(int));

  192.     tmp2.values = av_mallocz(256 * sizeof(int));

  193. 

  194.     memset(&vlc[0], 0, sizeof(VLC));

  195.     memset(&vlc[1], 0, sizeof(VLC));

  196. 

  197.     if(get_bits1(gb)) {

  198.         smacker_decode_tree(gb, &tmp1, 0, 0);

  199.         get_bits1(gb);

  200.         res = init_vlc(&vlc[0], SMKTREE_BITS, tmp1.length,

  201.                     tmp1.lengths, sizeof(int), sizeof(int),

  202.                     tmp1.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);

  203.         if(res < 0) {

  204.             av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");

  205.             return -1;

  206.         }

  207.     } else {

  208.         av_log(smk->avctx, AV_LOG_ERROR, "Skipping low bytes tree\n");

  209.     }

  210.     if(get_bits1(gb)){

  211.         smacker_decode_tree(gb, &tmp2, 0, 0);

  212.         get_bits1(gb);

  213.         res = init_vlc(&vlc[1], SMKTREE_BITS, tmp2.length,

  214.                     tmp2.lengths, sizeof(int), sizeof(int),

  215.                     tmp2.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);

  216.         if(res < 0) {

  217.             av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");

  218.             return -1;

  219.         }

  220.     } else {

  221.         av_log(smk->avctx, AV_LOG_ERROR, "Skipping high bytes tree\n");

  222.     }

  223. 

  224.     escapes[0]  = get_bits(gb, 8);

  225.     escapes[0] |= get_bits(gb, 8) << 8;

  226.     escapes[1]  = get_bits(gb, 8);

  227.     escapes[1] |= get_bits(gb, 8) << 8;

  228.     escapes[2]  = get_bits(gb, 8);

  229.     escapes[2] |= get_bits(gb, 8) << 8;

  230. 

  231.     last[0] = last[1] = last[2] = -1;

  232. 

  233.     ctx.escapes[0] = escapes[0];

  234.     ctx.escapes[1] = escapes[1];

  235.     ctx.escapes[2] = escapes[2];

  236.     ctx.v1 = &vlc[0];

  237.     ctx.v2 = &vlc[1];

  238.     ctx.recode1 = tmp1.values;

  239.     ctx.recode2 = tmp2.values;

  240.     ctx.last = last;

  241. 

  242.     huff.length = ((size + 3) >> 2) + 3;

  243.     huff.maxlength = 0;

  244.     huff.current = 0;

  245.     huff.values = av_mallocz(huff.length * sizeof(int));

  246. 

  247.     smacker_decode_bigtree(gb, &huff, &ctx);

  248.     get_bits1(gb);

  249.     if(ctx.last[0] == -1) ctx.last[0] = huff.current++;

  250.     if(ctx.last[1] == -1) ctx.last[1] = huff.current++;

  251.     if(ctx.last[2] == -1) ctx.last[2] = huff.current++;

  252. 

  253.     *recodes = huff.values;

  254. 

  255.     if(vlc[0].table)

  256.         free_vlc(&vlc[0]);

  257.     if(vlc[1].table)

  258.         free_vlc(&vlc[1]);

  259.     av_free(tmp1.bits);

  260.     av_free(tmp1.lengths);

  261.     av_free(tmp1.values);

  262.     av_free(tmp2.bits);

  263.     av_free(tmp2.lengths);

  264.     av_free(tmp2.values);

  265. 

  266.     return 0;

  267. }

  268. 

  269. static int decode_header_trees(SmackVContext *smk) {

  270.     GetBitContext gb;

  271.     int mmap_size, mclr_size, full_size, type_size;

  272. 

  273.     mmap_size = LE_32(smk->avctx->extradata);

  274.     mclr_size = LE_32(smk->avctx->extradata + 4);

  275.     full_size = LE_32(smk->avctx->extradata + 8);

  276.     type_size = LE_32(smk->avctx->extradata + 12);

  277. 

  278.     init_get_bits(&gb, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);

  279. 

  280.     if(!get_bits1(&gb)) {

  281.         av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");

  282.         smk->mmap_tbl = av_malloc(sizeof(int) * 2);

  283.         smk->mmap_tbl[0] = 0;

  284.         smk->mmap_last[0] = smk->mmap_last[1] = smk->mmap_last[2] = 1;

  285.     } else {

  286.         smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size);

  287.     }

  288.     if(!get_bits(&gb, 1)) {

  289.         av_log(smk->avctx, AV_LOG_INFO, "Skipping MCLR tree\n");

  290.         smk->mclr_tbl = av_malloc(sizeof(int) * 2);

  291.         smk->mclr_tbl[0] = 0;

  292.         smk->mclr_last[0] = smk->mclr_last[1] = smk->mclr_last[2] = 1;

  293.     } else {

  294.         smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size);

  295.     }

  296.     if(!get_bits(&gb, 1)) {

  297.         av_log(smk->avctx, AV_LOG_INFO, "Skipping FULL tree\n");

  298.         smk->full_tbl = av_malloc(sizeof(int) * 2);

  299.         smk->full_tbl[0] = 0;

  300.         smk->full_last[0] = smk->full_last[1] = smk->full_last[2] = 1;

  301.     } else {

  302.         smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size);

  303.     }

  304.     if(!get_bits(&gb, 1)) {

  305.         av_log(smk->avctx, AV_LOG_INFO, "Skipping TYPE tree\n");

  306.         smk->type_tbl = av_malloc(sizeof(int) * 2);

  307.         smk->type_tbl[0] = 0;

  308.         smk->type_last[0] = smk->type_last[1] = smk->type_last[2] = 1;

  309.     } else {

  310.         smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size);

  311.     }

  312. 

  313.     return 0;

  314. }

  315. 

  316. static always_inline void last_reset(int *recode, int *last) {

  317.     recode[last[0]] = recode[last[1]] = recode[last[2]] = 0;

  318. }

  319. 

  320. /* get code and update history */

  321. static always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {

  322.     register int *table = recode;

  323.     int v, b;

  324. 

  325.     b = get_bits_count(gb);

  326.     while(*table & SMK_NODE) {

  327.         if(get_bits1(gb))

  328.             table += (*table) & (~SMK_NODE);

  329.         table++;

  330.     }

  331.     v = *table;

  332.     b = get_bits_count(gb) - b;

  333. 

  334.     if(v != recode[last[0]]) {

  335.         recode[last[2]] = recode[last[1]];

  336.         recode[last[1]] = recode[last[0]];

  337.         recode[last[0]] = v;

  338.     }

  339.     return v;

  340. }

  341. 

  342. static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)

  343. {

  344.     SmackVContext * const smk = (SmackVContext *)avctx->priv_data;

  345.     uint8_t *out;

  346.     uint32_t *pal;

  347.     GetBitContext gb;

  348.     int blocks, blk, bw, bh;

  349.     int i;

  350.     int stride;

  351. 

  352.     if(buf_size == 769)

  353.         return 0;

  354.     if(smk->pic.data[0])

  355.             avctx->release_buffer(avctx, &smk->pic);

  356. 

  357.     smk->pic.reference = 1;

  358.     smk->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;

  359.     if(avctx->reget_buffer(avctx, &smk->pic) < 0){

  360.         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

  361.         return -1;

  362.     }

  363. 

  364.     /* make the palette available on the way out */

  365.     out = buf + 1;

  366.     pal = (uint32_t*)smk->pic.data[1];

  367.     smk->pic.palette_has_changed = buf[0] & 1;

  368.     smk->pic.key_frame = !!(buf[0] & 2);

  369.     if(smk->pic.key_frame)

  370.         smk->pic.pict_type = FF_I_TYPE;

  371.     else

  372.         smk->pic.pict_type = FF_P_TYPE;

  373. 

  374.     for(i = 0; i < 256; i++) {

  375.         int r, g, b;

  376.         r = *out++;

  377.         g = *out++;

  378.         b = *out++;

  379.         *pal++ = (r << 16) | (g << 8) | b;

  380.     }

  381. 

  382.     last_reset(smk->mmap_tbl, smk->mmap_last);

  383.     last_reset(smk->mclr_tbl, smk->mclr_last);

  384.     last_reset(smk->full_tbl, smk->full_last);

  385.     last_reset(smk->type_tbl, smk->type_last);

  386.     init_get_bits(&gb, buf + 769, (buf_size - 769) * 8);

  387. 

  388.     blk = 0;

  389.     bw = avctx->width >> 2;

  390.     bh = avctx->height >> 2;

  391.     blocks = bw * bh;

  392.     out = smk->pic.data[0];

  393.     stride = smk->pic.linesize[0];

  394.     while(blk < blocks) {

  395.         int type, run, mode;

  396.         uint16_t pix;

  397. 

  398.         type = smk_get_code(&gb, smk->type_tbl, smk->type_last);

  399.         run = block_runs[(type >> 2) & 0x3F];

  400.         switch(type & 3){

  401.         case SMK_BLK_MONO:

  402.             while(run-- && blk < blocks){

  403.                 int clr, map;

  404.                 int hi, lo;

  405.                 clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);

  406.                 map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);

  407.                 out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;

  408.                 hi = clr >> 8;

  409.                 lo = clr & 0xFF;

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

  411.                     if(map & 1) out[0] = hi; else out[0] = lo;

  412.                     if(map & 2) out[1] = hi; else out[1] = lo;

  413.                     if(map & 4) out[2] = hi; else out[2] = lo;

  414.                     if(map & 8) out[3] = hi; else out[3] = lo;

  415.                     map >>= 4;

  416.                     out += stride;

  417.                 }

  418.                 blk++;

  419.             }

  420.             break;

  421.         case SMK_BLK_FULL:

  422.             mode = 0;

  423.             if(avctx->codec_tag != 0) { // In case of Smacker v4 we have three modes

  424.                 if(get_bits1(&gb)) mode = 1;

  425.                 else if(get_bits1(&gb)) mode = 2;

  426.             }

  427.             while(run-- && blk < blocks){

  428.                 out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;

  429.                 switch(mode){

  430.                 case 0:

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

  432.                         pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  433.                         out[2] = pix & 0xFF;

  434.                         out[3] = pix >> 8;

  435.                         pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  436.                         out[0] = pix & 0xFF;

  437.                         out[1] = pix >> 8;

  438.                         out += stride;

  439.                     }

  440.                     break;

  441.                 case 1:

  442.                     pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  443.                     out[0] = out[1] = pix & 0xFF;

  444.                     out[2] = out[3] = pix >> 8;

  445.                     out += stride;

  446.                     out[0] = out[1] = pix & 0xFF;

  447.                     out[2] = out[3] = pix >> 8;

  448.                     out += stride;

  449.                     pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  450.                     out[0] = out[1] = pix & 0xFF;

  451.                     out[2] = out[3] = pix >> 8;

  452.                     out += stride;

  453.                     out[0] = out[1] = pix & 0xFF;

  454.                     out[2] = out[3] = pix >> 8;

  455.                     out += stride;

  456.                     break;

  457.                 case 2:

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

  459.                         uint16_t pix1, pix2;

  460.                         pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  461.                         pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);

  462.                         out[0] = pix1 & 0xFF; out[1] = pix1 >> 8;

  463.                         out[2] = pix2 & 0xFF; out[3] = pix2 >> 8;

  464.                         out += stride;

  465.                         out[0] = pix1 & 0xFF; out[1] = pix1 >> 8;

  466.                         out[2] = pix2 & 0xFF; out[3] = pix2 >> 8;

  467.                         out += stride;

  468.                     }

  469.                     break;

  470.                 }

  471.                 blk++;

  472.             }

  473.             break;

  474.         case SMK_BLK_SKIP:

  475.             while(run-- && blk < blocks)

  476.                 blk++;

  477.             break;

  478.         case SMK_BLK_FILL:

  479.             mode = type >> 8;

  480.             while(run-- && blk < blocks){

  481.                 uint32_t col;

  482.                 out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;

  483.                 col = mode * 0x01010101;

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

  485.                     *((uint32_t*)out) = col;

  486.                     out += stride;

  487.                 }

  488.                 blk++;

  489.             }

  490.             break;

  491.         }

  492. 

  493.     }

  494. 

  495.     *data_size = sizeof(AVFrame);

  496.     *(AVFrame*)data = smk->pic;

  497. 

  498.     /* always report that the buffer was completely consumed */

  499.     return buf_size;

  500. }

  501. 

  502. 

  503. 

  504. /*

  505.  *

  506.  * Init smacker decoder

  507.  *

  508.  */

  509. static int decode_init(AVCodecContext *avctx)

  510. {

  511.     SmackVContext * const c = (SmackVContext *)avctx->priv_data;

  512. 

  513.     c->avctx = avctx;

  514.     avctx->has_b_frames = 0;

  515. 

  516.     c->pic.data[0] = NULL;

  517. 

  518.     if (avcodec_check_dimensions(avctx, avctx->height, avctx->width) < 0) {

  519.         return 1;

  520.     }

  521. 

  522.     avctx->pix_fmt = PIX_FMT_PAL8;

  523. 

  524. 

  525.     /* decode huffman trees from extradata */

  526.     if(avctx->extradata_size < 16){

  527.         av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");

  528.         return -1;

  529.     }

  530. 

  531.     decode_header_trees(c);

  532. 

  533. 

  534.     return 0;

  535. }

  536. 

  537. 

  538. 

  539. /*

  540.  *

  541.  * Uninit smacker decoder

  542.  *

  543.  */

  544. static int decode_end(AVCodecContext *avctx)

  545. {

  546.     SmackVContext * const smk = (SmackVContext *)avctx->priv_data;

  547. 

  548.     if(smk->mmap_tbl)

  549.         av_free(smk->mmap_tbl);

  550.     if(smk->mclr_tbl)

  551.         av_free(smk->mclr_tbl);

  552.     if(smk->full_tbl)

  553.         av_free(smk->full_tbl);

  554.     if(smk->type_tbl)

  555.         av_free(smk->type_tbl);

  556. 

  557.     if (smk->pic.data[0])

  558.         avctx->release_buffer(avctx, &smk->pic);

  559. 

  560.     return 0;

  561. }

  562. 

  563. 

  564. static int smka_decode_init(AVCodecContext *avctx)

  565. {

  566.     return 0;

  567. }

  568. 

  569. /**

  570.  * Decode Smacker audio data

  571.  */

  572. static int smka_decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)

  573. {

  574.     GetBitContext gb;

  575.     HuffContext h[4];

  576.     VLC vlc[4];

  577.     int16_t *samples = data;

  578.     int val;

  579.     int i, res;

  580.     int unp_size;

  581.     int bits, stereo;

  582.     int pred[2] = {0, 0};

  583. 

  584.     unp_size = LE_32(buf);

  585. 

  586.     init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);

  587. 

  588.     if(!get_bits1(&gb)){

  589.         av_log(avctx, AV_LOG_INFO, "Sound: no data\n");

  590.         *data_size = 0;

  591.         return 1;

  592.     }

  593.     stereo = get_bits1(&gb);

  594.     bits = get_bits1(&gb);

  595. 

  596.     memset(vlc, 0, sizeof(VLC) * 4);

  597.     memset(h, 0, sizeof(HuffContext) * 4);

  598.     // Initialize

  599.     for(i = 0; i < (1 << (bits + stereo)); i++) {

  600.         h[i].length = 256;

  601.         h[i].maxlength = 0;

  602.         h[i].current = 0;

  603.         h[i].bits = av_mallocz(256 * 4);

  604.         h[i].lengths = av_mallocz(256 * sizeof(int));

  605.         h[i].values = av_mallocz(256 * sizeof(int));

  606.         get_bits1(&gb);

  607.         smacker_decode_tree(&gb, &h[i], 0, 0);

  608.         get_bits1(&gb);

  609.         if(h[i].current > 1) {

  610.             res = init_vlc(&vlc[i], SMKTREE_BITS, h[i].length,

  611.                     h[i].lengths, sizeof(int), sizeof(int),

  612.                     h[i].bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);

  613.             if(res < 0) {

  614.                 av_log(avctx, AV_LOG_ERROR, "Cannot build VLC table\n");

  615.                 return -1;

  616.             }

  617.         }

  618.     }

  619.     if(bits) { //decode 16-bit data

  620.         pred[0]  = get_bits(&gb, 8);

  621.         pred[0] |= get_bits(&gb, 8);

  622.         *samples++ = pred[0];

  623.         if(stereo) {

  624.             pred[1]  = get_bits(&gb, 8);

  625.             pred[1] |= get_bits(&gb, 8);

  626.             *samples++ = pred[1];

  627.         }

  628.         for(i = 0; i < unp_size / 2; i++) {

  629.             if(i & stereo) {

  630.                 if(vlc[2].table)

  631.                     res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);

  632.                 else

  633.                     res = 0;

  634.                 val  = h[2].values[res];

  635.                 if(vlc[3].table)

  636.                     res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);

  637.                 else

  638.                     res = 0;

  639.                 val |= h[3].values[res] << 8;

  640.                 pred[1] += (int16_t)val;

  641.                 *samples++ = pred[1];

  642.             } else {

  643.                 if(vlc[0].table)

  644.                     res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);

  645.                 else

  646.                     res = 0;

  647.                 val  = h[0].values[res];

  648.                 if(vlc[1].table)

  649.                     res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);

  650.                 else

  651.                     res = 0;

  652.                 val |= h[1].values[res] << 8;

  653.                 pred[0] += val;

  654.                 *samples++ = pred[0];

  655.             }

  656.         }

  657.     } else { //8-bit data

  658.         pred[0] = get_bits(&gb, 8);

  659.         *samples++ = (pred[0] - 0x80) << 8;

  660.         if(stereo) {

  661.             pred[1] = get_bits(&gb, 8);

  662.             *samples++ = (pred[1] - 0x80) << 8;

  663.         }

  664.         for(i = 0; i < unp_size; i++) {

  665.             if(i & stereo){

  666.                 if(vlc[1].table)

  667.                     res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);

  668.                 else

  669.                     res = 0;

  670.                 pred[1] += (int8_t)h[1].values[res];

  671.                 *samples++ = (pred[1] - 0x80) << 8;

  672.             } else {

  673.                 if(vlc[0].table)

  674.                     res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);

  675.                 else

  676.                     res = 0;

  677.                 pred[0] += (int8_t)h[0].values[res];

  678.                 *samples++ = (pred[0] - 0x80) << 8;

  679.             }

  680.         }

  681.         unp_size *= 2;

  682.     }

  683. 

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

  685.         if(vlc[i].table)

  686.             free_vlc(&vlc[i]);

  687.         if(h[i].bits)

  688.             av_free(h[i].bits);

  689.         if(h[i].lengths)

  690.             av_free(h[i].lengths);

  691.         if(h[i].values)

  692.             av_free(h[i].values);

  693.     }

  694. 

  695.     *data_size = unp_size;

  696.     return buf_size;

  697. }

  698. 

  699. AVCodec smacker_decoder = {

  700.     "smackvid",

  701.     CODEC_TYPE_VIDEO,

  702.     CODEC_ID_SMACKVIDEO,

  703.     sizeof(SmackVContext),

  704.     decode_init,

  705.     NULL,

  706.     decode_end,

  707.     decode_frame

  708. };

  709. 

  710. AVCodec smackaud_decoder = {

  711.     "smackaud",

  712.     CODEC_TYPE_AUDIO,

  713.     CODEC_ID_SMACKAUDIO,

  714.     0,

  715.     smka_decode_init,

  716.     NULL,

  717.     NULL,

  718.     smka_decode_frame

  719. };