falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
45081 Commits
32 Branches
303MB
Tree: 31a53ab34e
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '31a53ab34e'
${ noResults }
FFmpeg/libavcodec/smacker.c

791 lines
24KB
Raw Blame History 

  1. /*

  2.  * Smacker decoder

  3.  * Copyright (c) 2006 Konstantin Shishkov

  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.  * Smacker decoder

  25.  */

  26. 

  27. /*

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

  29.  */

  30. 

  31. #include <stdio.h>

  32. #include <stdlib.h>

  33. 

  34. #include "libavutil/channel_layout.h"

  35. 

  36. #define BITSTREAM_READER_LE

  37. #include "avcodec.h"

  38. #include "bitstream.h"

  39. #include "bytestream.h"

  40. #include "internal.h"

  41. #include "mathops.h"

  42. #include "vlc.h"

  43. 

  44. #define SMKTREE_BITS 9

  45. #define SMK_NODE 0x80000000

  46. #define SMKTREE_DECODE_MAX_RECURSION 32

  47. #define SMKTREE_DECODE_BIG_MAX_RECURSION 500

  48. 

  49. typedef struct SmackVContext {

  50.     AVCodecContext *avctx;

  51.     AVFrame *pic;

  52. 

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

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

  55. } SmackVContext;

  56. 

  57. /**

  58.  * Context used for code reconstructing

  59.  */

  60. typedef struct HuffContext {

  61.     int length;

  62.     int maxlength;

  63.     int current;

  64.     uint32_t *bits;

  65.     int *lengths;

  66.     int *values;

  67. } HuffContext;

  68. 

  69. /* common parameters used for decode_bigtree */

  70. typedef struct DBCtx {

  71.     VLC *v1, *v2;

  72.     int *recode1, *recode2;

  73.     int escapes[3];

  74.     int *last;

  75.     int lcur;

  76. } DBCtx;

  77. 

  78. /* possible runs of blocks */

  79. static const int block_runs[64] = {

  80.       1,    2,    3,    4,    5,    6,    7,    8,

  81.       9,   10,   11,   12,   13,   14,   15,   16,

  82.      17,   18,   19,   20,   21,   22,   23,   24,

  83.      25,   26,   27,   28,   29,   30,   31,   32,

  84.      33,   34,   35,   36,   37,   38,   39,   40,

  85.      41,   42,   43,   44,   45,   46,   47,   48,

  86.      49,   50,   51,   52,   53,   54,   55,   56,

  87.      57,   58,   59,  128,  256,  512, 1024, 2048 };

  88. 

  89. enum SmkBlockTypes {

  90.     SMK_BLK_MONO = 0,

  91.     SMK_BLK_FULL = 1,

  92.     SMK_BLK_SKIP = 2,

  93.     SMK_BLK_FILL = 3 };

  94. 

  95. /**

  96.  * Decode local frame tree

  97.  */

  98. static int smacker_decode_tree(BitstreamContext *bc, HuffContext *hc,

  99.                                uint32_t prefix, int length)

  100. {

  101.     if (length > SMKTREE_DECODE_MAX_RECURSION) {

  102.         av_log(NULL, AV_LOG_ERROR, "Maximum tree recursion level exceeded.\n");

  103.         return AVERROR_INVALIDDATA;

  104.     }

  105. 

  106.     if (!bitstream_read_bit(bc)) { // Leaf

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

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

  109.             return AVERROR_INVALIDDATA;

  110.         }

  111.         if(length){

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

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

  114.         } else {

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

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

  117.         }

  118.         hc->values[hc->current] = bitstream_read(bc, 8);

  119.         hc->current++;

  120.         if(hc->maxlength < length)

  121.             hc->maxlength = length;

  122.         return 0;

  123.     } else { //Node

  124.         int r;

  125.         length++;

  126.         r = smacker_decode_tree(bc, hc, prefix, length);

  127.         if(r)

  128.             return r;

  129.         return smacker_decode_tree(bc, hc, prefix | (1 << (length - 1)), length);

  130.     }

  131. }

  132. 

  133. /**

  134.  * Decode header tree

  135.  */

  136. static int smacker_decode_bigtree(BitstreamContext *bc, HuffContext *hc,

  137.                                   DBCtx *ctx, int length)

  138. {

  139.     // Larger length can cause segmentation faults due to too deep recursion.

  140.     if (length > SMKTREE_DECODE_BIG_MAX_RECURSION) {

  141.         av_log(NULL, AV_LOG_ERROR, "Maximum bigtree recursion level exceeded.\n");

  142.         return AVERROR_INVALIDDATA;

  143.     }

  144. 

  145.     if (hc->current + 1 >= hc->length) {

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

  147.         return AVERROR_INVALIDDATA;

  148.     }

  149.     if (!bitstream_read_bit(bc)) { // Leaf

  150.         int val, i1, i2;

  151.         i1 = ctx->v1->table ? bitstream_read_vlc(bc, ctx->v1->table, SMKTREE_BITS, 3) : 0;

  152.         i2 = ctx->v2->table ? bitstream_read_vlc(bc, ctx->v2->table, SMKTREE_BITS, 3) : 0;

  153.         if (i1 < 0 || i2 < 0)

  154.             return AVERROR_INVALIDDATA;

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

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

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

  158.             val = 0;

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

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

  161.             val = 0;

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

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

  164.             val = 0;

  165.         }

  166. 

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

  168.         return 1;

  169.     } else { //Node

  170.         int r = 0, r_new, t;

  171. 

  172.         t = hc->current++;

  173.         r = smacker_decode_bigtree(bc, hc, ctx, length + 1);

  174.         if(r < 0)

  175.             return r;

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

  177.         r++;

  178.         r_new = smacker_decode_bigtree(bc, hc, ctx, length + 1);

  179.         if (r_new < 0)

  180.             return r_new;

  181.         return r + r_new;

  182.     }

  183. }

  184. 

  185. /**

  186.  * Store large tree as Libav's vlc codes

  187.  */

  188. static int smacker_decode_header_tree(SmackVContext *smk, BitstreamContext *bc,

  189.                                       int **recodes, int *last, int size)

  190. {

  191.     int res;

  192.     HuffContext huff;

  193.     HuffContext tmp1, tmp2;

  194.     VLC vlc[2] = { { 0 } };

  195.     int escapes[3];

  196.     DBCtx ctx;

  197.     int err = 0;

  198. 

  199.     if(size >= UINT_MAX>>4){ // (((size + 3) >> 2) + 3) << 2 must not overflow

  200.         av_log(smk->avctx, AV_LOG_ERROR, "size too large\n");

  201.         return AVERROR_INVALIDDATA;

  202.     }

  203. 

  204.     tmp1.length = 256;

  205.     tmp1.maxlength = 0;

  206.     tmp1.current = 0;

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

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

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

  210. 

  211.     tmp2.length = 256;

  212.     tmp2.maxlength = 0;

  213.     tmp2.current = 0;

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

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

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

  217.     if (!tmp1.bits || !tmp1.lengths || !tmp1.values ||

  218.         !tmp2.bits || !tmp2.lengths || !tmp2.values) {

  219.         err = AVERROR(ENOMEM);

  220.         goto error;

  221.     }

  222. 

  223.     if (bitstream_read_bit(bc)) {

  224.         smacker_decode_tree(bc, &tmp1, 0, 0);

  225.         bitstream_skip(bc, 1);

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

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

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

  229.         if(res < 0) {

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

  231.             err = res;

  232.             goto error;

  233.         }

  234.     } else {

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

  236.     }

  237.     if (bitstream_read_bit(bc)) {

  238.         smacker_decode_tree(bc, &tmp2, 0, 0);

  239.         bitstream_skip(bc, 1);

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

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

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

  243.         if(res < 0) {

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

  245.             err = res;

  246.             goto error;

  247.         }

  248.     } else {

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

  250.     }

  251. 

  252.     escapes[0]  = bitstream_read(bc, 8);

  253.     escapes[0] |= bitstream_read(bc, 8) << 8;

  254.     escapes[1]  = bitstream_read(bc, 8);

  255.     escapes[1] |= bitstream_read(bc, 8) << 8;

  256.     escapes[2]  = bitstream_read(bc, 8);

  257.     escapes[2] |= bitstream_read(bc, 8) << 8;

  258. 

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

  260. 

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

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

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

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

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

  266.     ctx.recode1 = tmp1.values;

  267.     ctx.recode2 = tmp2.values;

  268.     ctx.last = last;

  269. 

  270.     huff.length = ((size + 3) >> 2) + 4;

  271.     huff.maxlength = 0;

  272.     huff.current = 0;

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

  274.     if (!huff.values) {

  275.         err = AVERROR(ENOMEM);

  276.         goto error;

  277.     }

  278. 

  279.     if ((res = smacker_decode_bigtree(bc, &huff, &ctx, 0)) < 0)

  280.         err = res;

  281.     bitstream_skip(bc, 1);

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

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

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

  285.     if (ctx.last[0] >= huff.length ||

  286.         ctx.last[1] >= huff.length ||

  287.         ctx.last[2] >= huff.length) {

  288.         av_log(smk->avctx, AV_LOG_ERROR, "Huffman codes out of range\n");

  289.         err = AVERROR_INVALIDDATA;

  290.     }

  291. 

  292.     *recodes = huff.values;

  293. 

  294. error:

  295.     if(vlc[0].table)

  296.         ff_free_vlc(&vlc[0]);

  297.     if(vlc[1].table)

  298.         ff_free_vlc(&vlc[1]);

  299.     av_free(tmp1.bits);

  300.     av_free(tmp1.lengths);

  301.     av_free(tmp1.values);

  302.     av_free(tmp2.bits);

  303.     av_free(tmp2.lengths);

  304.     av_free(tmp2.values);

  305. 

  306.     return err;

  307. }

  308. 

  309. static int decode_header_trees(SmackVContext *smk) {

  310.     BitstreamContext bc;

  311.     int mmap_size, mclr_size, full_size, type_size, ret;

  312. 

  313.     mmap_size = AV_RL32(smk->avctx->extradata);

  314.     mclr_size = AV_RL32(smk->avctx->extradata + 4);

  315.     full_size = AV_RL32(smk->avctx->extradata + 8);

  316.     type_size = AV_RL32(smk->avctx->extradata + 12);

  317. 

  318.     bitstream_init8(&bc, smk->avctx->extradata + 16, smk->avctx->extradata_size - 16);

  319. 

  320.     if (!bitstream_read_bit(&bc)) {

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

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

  323.         if (!smk->mmap_tbl)

  324.             return AVERROR(ENOMEM);

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

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

  327.     } else {

  328.         if ((ret = smacker_decode_header_tree(smk, &bc, &smk->mmap_tbl, smk->mmap_last, mmap_size)) < 0)

  329.             return ret;

  330.     }

  331.     if (!bitstream_read_bit(&bc)) {

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

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

  334.         if (!smk->mclr_tbl)

  335.             return AVERROR(ENOMEM);

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

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

  338.     } else {

  339.         if ((ret = smacker_decode_header_tree(smk, &bc, &smk->mclr_tbl, smk->mclr_last, mclr_size)) < 0)

  340.             return ret;

  341.     }

  342.     if (!bitstream_read_bit(&bc)) {

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

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

  345.         if (!smk->full_tbl)

  346.             return AVERROR(ENOMEM);

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

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

  349.     } else {

  350.         if ((ret = smacker_decode_header_tree(smk, &bc, &smk->full_tbl, smk->full_last, full_size)) < 0)

  351.             return ret;

  352.     }

  353.     if (!bitstream_read_bit(&bc)) {

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

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

  356.         if (!smk->type_tbl)

  357.             return AVERROR(ENOMEM);

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

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

  360.     } else {

  361.         if ((ret = smacker_decode_header_tree(smk, &bc, &smk->type_tbl, smk->type_last, type_size)) < 0)

  362.             return ret;

  363.     }

  364. 

  365.     return 0;

  366. }

  367. 

  368. static av_always_inline void last_reset(int *recode, int *last) {

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

  370. }

  371. 

  372. /* get code and update history */

  373. static av_always_inline int smk_get_code(BitstreamContext *bc, int *recode,

  374.                                          int *last)

  375. {

  376.     register int *table = recode;

  377.     int v;

  378. 

  379.     while(*table & SMK_NODE) {

  380.         if (bitstream_read_bit(bc))

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

  382.         table++;

  383.     }

  384.     v = *table;

  385. 

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

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

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

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

  390.     }

  391.     return v;

  392. }

  393. 

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

  395.                         AVPacket *avpkt)

  396. {

  397.     SmackVContext * const smk = avctx->priv_data;

  398.     uint8_t *out;

  399.     uint32_t *pal;

  400.     GetByteContext gb2;

  401.     BitstreamContext bc;

  402.     int blocks, blk, bw, bh;

  403.     int i, ret;

  404.     int stride;

  405.     int flags;

  406. 

  407.     if (avpkt->size <= 769)

  408.         return 0;

  409. 

  410.     if ((ret = ff_reget_buffer(avctx, smk->pic)) < 0) {

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

  412.         return ret;

  413.     }

  414. 

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

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

  417.     bytestream2_init(&gb2, avpkt->data, avpkt->size);

  418.     flags = bytestream2_get_byteu(&gb2);

  419.     smk->pic->palette_has_changed = flags & 1;

  420.     smk->pic->key_frame = !!(flags & 2);

  421.     if(smk->pic->key_frame)

  422.         smk->pic->pict_type = AV_PICTURE_TYPE_I;

  423.     else

  424.         smk->pic->pict_type = AV_PICTURE_TYPE_P;

  425. 

  426.     for(i = 0; i < 256; i++)

  427.         *pal++ = bytestream2_get_be24u(&gb2);

  428. 

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

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

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

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

  433.     bitstream_init8(&bc, avpkt->data + 769, avpkt->size - 769);

  434. 

  435.     blk = 0;

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

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

  438.     blocks = bw * bh;

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

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

  441.     while(blk < blocks) {

  442.         int type, run, mode;

  443.         uint16_t pix;

  444. 

  445.         type = smk_get_code(&bc, smk->type_tbl, smk->type_last);

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

  447.         switch(type & 3){

  448.         case SMK_BLK_MONO:

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

  450.                 int clr, map;

  451.                 int hi, lo;

  452.                 clr = smk_get_code(&bc, smk->mclr_tbl, smk->mclr_last);

  453.                 map = smk_get_code(&bc, smk->mmap_tbl, smk->mmap_last);

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

  455.                 hi = clr >> 8;

  456.                 lo = clr & 0xFF;

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

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

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

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

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

  462.                     map >>= 4;

  463.                     out += stride;

  464.                 }

  465.                 blk++;

  466.             }

  467.             break;

  468.         case SMK_BLK_FULL:

  469.             mode = 0;

  470.             if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes

  471.                 if (bitstream_read_bit(&bc))

  472.                     mode = 1;

  473.                 else if (bitstream_read_bit(&bc))

  474.                     mode = 2;

  475.             }

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

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

  478.                 switch(mode){

  479.                 case 0:

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

  481.                         pix = smk_get_code(&bc, smk->full_tbl, smk->full_last);

  482.                         AV_WL16(out+2,pix);

  483.                         pix = smk_get_code(&bc, smk->full_tbl, smk->full_last);

  484.                         AV_WL16(out,pix);

  485.                         out += stride;

  486.                     }

  487.                     break;

  488.                 case 1:

  489.                     pix = smk_get_code(&bc, smk->full_tbl, smk->full_last);

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

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

  492.                     out += stride;

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

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

  495.                     out += stride;

  496.                     pix = smk_get_code(&bc, smk->full_tbl, smk->full_last);

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

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

  499.                     out += stride;

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

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

  502.                     out += stride;

  503.                     break;

  504.                 case 2:

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

  506.                         uint16_t pix1, pix2;

  507.                         pix2 = smk_get_code(&bc, smk->full_tbl, smk->full_last);

  508.                         pix1 = smk_get_code(&bc, smk->full_tbl, smk->full_last);

  509.                         AV_WL16(out,pix1);

  510.                         AV_WL16(out+2,pix2);

  511.                         out += stride;

  512.                         AV_WL16(out,pix1);

  513.                         AV_WL16(out+2,pix2);

  514.                         out += stride;

  515.                     }

  516.                     break;

  517.                 }

  518.                 blk++;

  519.             }

  520.             break;

  521.         case SMK_BLK_SKIP:

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

  523.                 blk++;

  524.             break;

  525.         case SMK_BLK_FILL:

  526.             mode = type >> 8;

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

  528.                 uint32_t col;

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

  530.                 col = mode * 0x01010101;

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

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

  533.                     out += stride;

  534.                 }

  535.                 blk++;

  536.             }

  537.             break;

  538.         }

  539. 

  540.     }

  541. 

  542.     if ((ret = av_frame_ref(data, smk->pic)) < 0)

  543.         return ret;

  544. 

  545.     *got_frame = 1;

  546. 

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

  548.     return avpkt->size;

  549. }

  550. 

  551. 

  552. static av_cold int decode_end(AVCodecContext *avctx)

  553. {

  554.     SmackVContext * const smk = avctx->priv_data;

  555. 

  556.     av_freep(&smk->mmap_tbl);

  557.     av_freep(&smk->mclr_tbl);

  558.     av_freep(&smk->full_tbl);

  559.     av_freep(&smk->type_tbl);

  560. 

  561.     av_frame_free(&smk->pic);

  562. 

  563.     return 0;

  564. }

  565. 

  566. 

  567. static av_cold int decode_init(AVCodecContext *avctx)

  568. {

  569.     SmackVContext * const c = avctx->priv_data;

  570.     int ret;

  571. 

  572.     c->avctx = avctx;

  573. 

  574.     avctx->pix_fmt = AV_PIX_FMT_PAL8;

  575. 

  576.     c->pic = av_frame_alloc();

  577.     if (!c->pic)

  578.         return AVERROR(ENOMEM);

  579. 

  580.     /* decode huffman trees from extradata */

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

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

  583.         return AVERROR_INVALIDDATA;

  584.     }

  585. 

  586.     if ((ret = decode_header_trees(c))) {

  587.         decode_end(avctx);

  588.         return ret;

  589.     }

  590. 

  591.     return 0;

  592. }

  593. 

  594. 

  595. 

  596. static av_cold int smka_decode_init(AVCodecContext *avctx)

  597. {

  598.     if (avctx->channels < 1 || avctx->channels > 2) {

  599.         av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");

  600.         return AVERROR_INVALIDDATA;

  601.     }

  602.     avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;

  603.     avctx->sample_fmt = avctx->bits_per_coded_sample == 8 ? AV_SAMPLE_FMT_U8 : AV_SAMPLE_FMT_S16;

  604. 

  605.     return 0;

  606. }

  607. 

  608. /**

  609.  * Decode Smacker audio data

  610.  */

  611. static int smka_decode_frame(AVCodecContext *avctx, void *data,

  612.                              int *got_frame_ptr, AVPacket *avpkt)

  613. {

  614.     AVFrame *frame     = data;

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

  616.     int buf_size = avpkt->size;

  617.     BitstreamContext bc;

  618.     HuffContext h[4] = { { 0 } };

  619.     VLC vlc[4]       = { { 0 } };

  620.     int16_t *samples;

  621.     uint8_t *samples8;

  622.     int val;

  623.     int i, res, ret;

  624.     int unp_size;

  625.     int bits, stereo;

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

  627. 

  628.     if (buf_size <= 4) {

  629.         av_log(avctx, AV_LOG_ERROR, "packet is too small\n");

  630.         return AVERROR_INVALIDDATA;

  631.     }

  632. 

  633.     unp_size = AV_RL32(buf);

  634. 

  635.     bitstream_init8(&bc, buf + 4, buf_size - 4);

  636. 

  637.     if (!bitstream_read_bit(&bc)) {

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

  639.         *got_frame_ptr = 0;

  640.         return 1;

  641.     }

  642.     stereo = bitstream_read_bit(&bc);

  643.     bits   = bitstream_read_bit(&bc);

  644.     if (stereo ^ (avctx->channels != 1)) {

  645.         av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");

  646.         return AVERROR_INVALIDDATA;

  647.     }

  648.     if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {

  649.         av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");

  650.         return AVERROR_INVALIDDATA;

  651.     }

  652.     if (unp_size % (avctx->channels * (bits + 1))) {

  653.         av_log(avctx, AV_LOG_ERROR,

  654.                "The buffer does not contain an integer number of samples\n");

  655.         return AVERROR_INVALIDDATA;

  656.     }

  657. 

  658.     /* get output buffer */

  659.     frame->nb_samples = unp_size / (avctx->channels * (bits + 1));

  660.     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {

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

  662.         return ret;

  663.     }

  664.     samples  = (int16_t *)frame->data[0];

  665.     samples8 =            frame->data[0];

  666. 

  667.     // Initialize

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

  669.         h[i].length = 256;

  670.         h[i].maxlength = 0;

  671.         h[i].current = 0;

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

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

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

  675.         if (!h[i].bits || !h[i].lengths || !h[i].values) {

  676.             ret = AVERROR(ENOMEM);

  677.             goto error;

  678.         }

  679.         bitstream_skip(&bc, 1);

  680.         if (smacker_decode_tree(&bc, &h[i], 0, 0) < 0) {

  681.             ret = AVERROR_INVALIDDATA;

  682.             goto error;

  683.         }

  684.         bitstream_skip(&bc, 1);

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

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

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

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

  689.             if(res < 0) {

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

  691.                 ret = AVERROR_INVALIDDATA;

  692.                 goto error;

  693.             }

  694.         }

  695.     }

  696.     /* this codec relies on wraparound instead of clipping audio */

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

  698.         for(i = stereo; i >= 0; i--)

  699.             pred[i] = sign_extend(av_bswap16(bitstream_read(&bc, 16)), 16);

  700.         for(i = 0; i <= stereo; i++)

  701.             *samples++ = pred[i];

  702.         for(; i < unp_size / 2; i++) {

  703.             if(i & stereo) {

  704.                 if(vlc[2].table)

  705.                     res = bitstream_read_vlc(&bc, vlc[2].table, SMKTREE_BITS, 3);

  706.                 else

  707.                     res = 0;

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

  709.                 if(vlc[3].table)

  710.                     res = bitstream_read_vlc(&bc, vlc[3].table, SMKTREE_BITS, 3);

  711.                 else

  712.                     res = 0;

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

  714.                 pred[1] += sign_extend(val, 16);

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

  716.             } else {

  717.                 if(vlc[0].table)

  718.                     res = bitstream_read_vlc(&bc, vlc[0].table, SMKTREE_BITS, 3);

  719.                 else

  720.                     res = 0;

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

  722.                 if(vlc[1].table)

  723.                     res = bitstream_read_vlc(&bc, vlc[1].table, SMKTREE_BITS, 3);

  724.                 else

  725.                     res = 0;

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

  727.                 pred[0] += sign_extend(val, 16);

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

  729.             }

  730.         }

  731.     } else { //8-bit data

  732.         for(i = stereo; i >= 0; i--)

  733.             pred[i] = bitstream_read(&bc, 8);

  734.         for(i = 0; i <= stereo; i++)

  735.             *samples8++ = pred[i];

  736.         for(; i < unp_size; i++) {

  737.             if(i & stereo){

  738.                 if(vlc[1].table)

  739.                     res = bitstream_read_vlc(&bc, vlc[1].table, SMKTREE_BITS, 3);

  740.                 else

  741.                     res = 0;

  742.                 pred[1] += sign_extend(h[1].values[res], 8);

  743.                 *samples8++ = pred[1];

  744.             } else {

  745.                 if(vlc[0].table)

  746.                     res = bitstream_read_vlc(&bc, vlc[0].table, SMKTREE_BITS, 3);

  747.                 else

  748.                     res = 0;

  749.                 pred[0] += sign_extend(h[0].values[res], 8);

  750.                 *samples8++ = pred[0];

  751.             }

  752.         }

  753.     }

  754. 

  755.     *got_frame_ptr = 1;

  756.     ret = buf_size;

  757. 

  758. error:

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

  760.         if(vlc[i].table)

  761.             ff_free_vlc(&vlc[i]);

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

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

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

  765.     }

  766. 

  767.     return ret;

  768. }

  769. 

  770. AVCodec ff_smacker_decoder = {

  771.     .name           = "smackvid",

  772.     .long_name      = NULL_IF_CONFIG_SMALL("Smacker video"),

  773.     .type           = AVMEDIA_TYPE_VIDEO,

  774.     .id             = AV_CODEC_ID_SMACKVIDEO,

  775.     .priv_data_size = sizeof(SmackVContext),

  776.     .init           = decode_init,

  777.     .close          = decode_end,

  778.     .decode         = decode_frame,

  779.     .capabilities   = AV_CODEC_CAP_DR1,

  780. };

  781. 

  782. AVCodec ff_smackaud_decoder = {

  783.     .name           = "smackaud",

  784.     .long_name      = NULL_IF_CONFIG_SMALL("Smacker audio"),

  785.     .type           = AVMEDIA_TYPE_AUDIO,

  786.     .id             = AV_CODEC_ID_SMACKAUDIO,

  787.     .init           = smka_decode_init,

  788.     .decode         = smka_decode_frame,

  789.     .capabilities   = AV_CODEC_CAP_DR1,

  790. };