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.
42072 Commits
32 Branches
552MB
Tree: e704ab3d5f
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from 'e704ab3d5f'
${ noResults }
FFmpeg/libavcodec/smacker.c

788 lines
24KB
Raw Blame History 

  1. /*

  2.  * Smacker decoder

  3.  * Copyright (c) 2006 Konstantin Shishkov

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

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

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

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

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

  11.  *

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

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

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

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

  20.  */

  21. 

  22. /**

  23.  * @file

  24.  * 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 "avcodec.h"

  35. #include "libavutil/audioconvert.h"

  36. #include "mathops.h"

  37. 

  38. #define BITSTREAM_READER_LE

  39. #include "get_bits.h"

  40. #include "bytestream.h"

  41. 

  42. #define SMKTREE_BITS 9

  43. #define SMK_NODE 0x80000000

  44. 

  45. /*

  46.  * Decoder context

  47.  */

  48. typedef struct SmackVContext {

  49.     AVCodecContext *avctx;

  50.     AVFrame pic;

  51. 

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

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

  54. } SmackVContext;

  55. 

  56. /**

  57.  * Context used for code reconstructing

  58.  */

  59. typedef struct HuffContext {

  60.     int length;

  61.     int maxlength;

  62.     int current;

  63.     uint32_t *bits;

  64.     int *lengths;

  65.     int *values;

  66. } HuffContext;

  67. 

  68. /* common parameters used for decode_bigtree */

  69. typedef struct DBCtx {

  70.     VLC *v1, *v2;

  71.     int *recode1, *recode2;

  72.     int escapes[3];

  73.     int *last;

  74.     int lcur;

  75. } DBCtx;

  76. 

  77. /* possible runs of blocks */

  78. static const int block_runs[64] = {

  79.       1,    2,    3,    4,    5,    6,    7,    8,

  80.       9,   10,   11,   12,   13,   14,   15,   16,

  81.      17,   18,   19,   20,   21,   22,   23,   24,

  82.      25,   26,   27,   28,   29,   30,   31,   32,

  83.      33,   34,   35,   36,   37,   38,   39,   40,

  84.      41,   42,   43,   44,   45,   46,   47,   48,

  85.      49,   50,   51,   52,   53,   54,   55,   56,

  86.      57,   58,   59,  128,  256,  512, 1024, 2048 };

  87. 

  88. enum SmkBlockTypes {

  89.     SMK_BLK_MONO = 0,

  90.     SMK_BLK_FULL = 1,

  91.     SMK_BLK_SKIP = 2,

  92.     SMK_BLK_FILL = 3 };

  93. 

  94. /**

  95.  * Decode local frame tree

  96.  */

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

  98. {

  99.     if(length > 32) {

  100.         av_log(NULL, AV_LOG_ERROR, "length too long\n");

  101.         return -1;

  102.     }

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

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

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

  106.             return -1;

  107.         }

  108.         if(length){

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

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

  111.         } else {

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

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

  114.         }

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

  116.         hc->current++;

  117.         if(hc->maxlength < length)

  118.             hc->maxlength = length;

  119.         return 0;

  120.     } else { //Node

  121.         int r;

  122.         length++;

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

  124.         if(r)

  125.             return r;

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

  127.     }

  128. }

  129. 

  130. /**

  131.  * Decode header tree

  132.  */

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

  134. {

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

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

  137.         return -1;

  138.     }

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

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

  141.         b1 = get_bits_count(gb);

  142.         i1 = ctx->v1->table ? get_vlc2(gb, ctx->v1->table, SMKTREE_BITS, 3) : 0;

  143.         b1 = get_bits_count(gb) - b1;

  144.         b2 = get_bits_count(gb);

  145.         i2 = ctx->v2->table ? get_vlc2(gb, ctx->v2->table, SMKTREE_BITS, 3) : 0;

  146.         b2 = get_bits_count(gb) - b2;

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

  148.             return -1;

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

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

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

  152.             val = 0;

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

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

  155.             val = 0;

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

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

  158.             val = 0;

  159.         }

  160. 

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

  162.         return 1;

  163.     } else { //Node

  164.         int r = 0, r_new, t;

  165. 

  166.         t = hc->current++;

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

  168.         if(r < 0)

  169.             return r;

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

  171.         r++;

  172.         r_new = smacker_decode_bigtree(gb, hc, ctx);

  173.         if (r_new < 0)

  174.             return r_new;

  175.         return r + r_new;

  176.     }

  177. }

  178. 

  179. /**

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

  181.  */

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

  183. {

  184.     int res;

  185.     HuffContext huff;

  186.     HuffContext tmp1, tmp2;

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

  188.     int escapes[3];

  189.     DBCtx ctx;

  190.     int err = 0;

  191. 

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

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

  194.         return -1;

  195.     }

  196. 

  197.     tmp1.length = 256;

  198.     tmp1.maxlength = 0;

  199.     tmp1.current = 0;

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

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

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

  203. 

  204.     tmp2.length = 256;

  205.     tmp2.maxlength = 0;

  206.     tmp2.current = 0;

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

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

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

  210. 

  211.     if(get_bits1(gb)) {

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

  213.         skip_bits1(gb);

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

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

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

  217.         if(res < 0) {

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

  219.             return -1;

  220.         }

  221.     } else {

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

  223.     }

  224.     if(get_bits1(gb)){

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

  226.         skip_bits1(gb);

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

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

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

  230.         if(res < 0) {

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

  232.             return -1;

  233.         }

  234.     } else {

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

  236.     }

  237. 

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

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

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

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

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

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

  244. 

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

  246. 

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

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

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

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

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

  252.     ctx.recode1 = tmp1.values;

  253.     ctx.recode2 = tmp2.values;

  254.     ctx.last = last;

  255. 

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

  257.     huff.maxlength = 0;

  258.     huff.current = 0;

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

  260. 

  261.     if (smacker_decode_bigtree(gb, &huff, &ctx) < 0)

  262.         err = -1;

  263.     skip_bits1(gb);

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

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

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

  267.     if(huff.current > huff.length){

  268.         ctx.last[0] = ctx.last[1] = ctx.last[2] = 1;

  269.         av_log(smk->avctx, AV_LOG_ERROR, "bigtree damaged\n");

  270.         return -1;

  271.     }

  272. 

  273.     *recodes = huff.values;

  274. 

  275.     if(vlc[0].table)

  276.         ff_free_vlc(&vlc[0]);

  277.     if(vlc[1].table)

  278.         ff_free_vlc(&vlc[1]);

  279.     av_free(tmp1.bits);

  280.     av_free(tmp1.lengths);

  281.     av_free(tmp1.values);

  282.     av_free(tmp2.bits);

  283.     av_free(tmp2.lengths);

  284.     av_free(tmp2.values);

  285. 

  286.     return err;

  287. }

  288. 

  289. static int decode_header_trees(SmackVContext *smk) {

  290.     GetBitContext gb;

  291.     int mmap_size, mclr_size, full_size, type_size;

  292. 

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

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

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

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

  297. 

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

  299. 

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

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

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

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

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

  305.     } else {

  306.         if (smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size))

  307.             return -1;

  308.     }

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

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

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

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

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

  314.     } else {

  315.         if (smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size))

  316.             return -1;

  317.     }

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

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

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

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

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

  323.     } else {

  324.         if (smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size))

  325.             return -1;

  326.     }

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

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

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

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

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

  332.     } else {

  333.         if (smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size))

  334.             return -1;

  335.     }

  336. 

  337.     return 0;

  338. }

  339. 

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

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

  342. }

  343. 

  344. /* get code and update history */

  345. static av_always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {

  346.     register int *table = recode;

  347.     int v;

  348. 

  349.     while(*table & SMK_NODE) {

  350.         if(get_bits1(gb))

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

  352.         table++;

  353.     }

  354.     v = *table;

  355. 

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

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

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

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

  360.     }

  361.     return v;

  362. }

  363. 

  364. static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)

  365. {

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

  367.     uint8_t *out;

  368.     uint32_t *pal;

  369.     GetByteContext gb2;

  370.     GetBitContext gb;

  371.     int blocks, blk, bw, bh;

  372.     int i;

  373.     int stride;

  374.     int flags;

  375. 

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

  377.         return 0;

  378. 

  379.     smk->pic.reference = 3;

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

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

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

  383.         return -1;

  384.     }

  385. 

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

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

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

  389.     flags = bytestream2_get_byteu(&gb2);

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

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

  392.     if(smk->pic.key_frame)

  393.         smk->pic.pict_type = AV_PICTURE_TYPE_I;

  394.     else

  395.         smk->pic.pict_type = AV_PICTURE_TYPE_P;

  396. 

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

  398.         *pal++ = 0xFF << 24 | bytestream2_get_be24u(&gb2);

  399. 

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

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

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

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

  404.     init_get_bits(&gb, avpkt->data + 769, (avpkt->size - 769) * 8);

  405. 

  406.     blk = 0;

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

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

  409.     blocks = bw * bh;

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

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

  412.     while(blk < blocks) {

  413.         int type, run, mode;

  414.         uint16_t pix;

  415. 

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

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

  418.         switch(type & 3){

  419.         case SMK_BLK_MONO:

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

  421.                 int clr, map;

  422.                 int hi, lo;

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

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

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

  426.                 hi = clr >> 8;

  427.                 lo = clr & 0xFF;

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

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

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

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

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

  433.                     map >>= 4;

  434.                     out += stride;

  435.                 }

  436.                 blk++;

  437.             }

  438.             break;

  439.         case SMK_BLK_FULL:

  440.             mode = 0;

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

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

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

  444.             }

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

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

  447.                 switch(mode){

  448.                 case 0:

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

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

  451.                         AV_WL16(out+2,pix);

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

  453.                         AV_WL16(out,pix);

  454.                         out += stride;

  455.                     }

  456.                     break;

  457.                 case 1:

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

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

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

  461.                     out += stride;

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

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

  464.                     out += stride;

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

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

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

  468.                     out += stride;

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

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

  471.                     out += stride;

  472.                     break;

  473.                 case 2:

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

  475.                         uint16_t pix1, pix2;

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

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

  478.                         AV_WL16(out,pix1);

  479.                         AV_WL16(out+2,pix2);

  480.                         out += stride;

  481.                         AV_WL16(out,pix1);

  482.                         AV_WL16(out+2,pix2);

  483.                         out += stride;

  484.                     }

  485.                     break;

  486.                 }

  487.                 blk++;

  488.             }

  489.             break;

  490.         case SMK_BLK_SKIP:

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

  492.                 blk++;

  493.             break;

  494.         case SMK_BLK_FILL:

  495.             mode = type >> 8;

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

  497.                 uint32_t col;

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

  499.                 col = mode * 0x01010101;

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

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

  502.                     out += stride;

  503.                 }

  504.                 blk++;

  505.             }

  506.             break;

  507.         }

  508. 

  509.     }

  510. 

  511.     *data_size = sizeof(AVFrame);

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

  513. 

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

  515.     return avpkt->size;

  516. }

  517. 

  518. 

  519. 

  520. /*

  521.  *

  522.  * Init smacker decoder

  523.  *

  524.  */

  525. static av_cold int decode_init(AVCodecContext *avctx)

  526. {

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

  528. 

  529.     c->avctx = avctx;

  530. 

  531.     avctx->pix_fmt = PIX_FMT_PAL8;

  532. 

  533.     avcodec_get_frame_defaults(&c->pic);

  534. 

  535.     /* decode huffman trees from extradata */

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

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

  538.         return -1;

  539.     }

  540. 

  541.     if (decode_header_trees(c))

  542.         return -1;

  543. 

  544.     return 0;

  545. }

  546. 

  547. 

  548. 

  549. /*

  550.  *

  551.  * Uninit smacker decoder

  552.  *

  553.  */

  554. static av_cold int decode_end(AVCodecContext *avctx)

  555. {

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

  557. 

  558.     av_freep(&smk->mmap_tbl);

  559.     av_freep(&smk->mclr_tbl);

  560.     av_freep(&smk->full_tbl);

  561.     av_freep(&smk->type_tbl);

  562. 

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

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

  565. 

  566.     return 0;

  567. }

  568. 

  569. 

  570. typedef struct SmackerAudioContext {

  571.     AVFrame frame;

  572. } SmackerAudioContext;

  573. 

  574. static av_cold int smka_decode_init(AVCodecContext *avctx)

  575. {

  576.     SmackerAudioContext *s = avctx->priv_data;

  577. 

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

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

  580.         return AVERROR(EINVAL);

  581.     }

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

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

  584. 

  585.     avcodec_get_frame_defaults(&s->frame);

  586.     avctx->coded_frame = &s->frame;

  587. 

  588.     return 0;

  589. }

  590. 

  591. /**

  592.  * Decode Smacker audio data

  593.  */

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

  595.                              int *got_frame_ptr, AVPacket *avpkt)

  596. {

  597.     SmackerAudioContext *s = avctx->priv_data;

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

  599.     int buf_size = avpkt->size;

  600.     GetBitContext gb;

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

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

  603.     int16_t *samples;

  604.     uint8_t *samples8;

  605.     int val;

  606.     int i, res, ret;

  607.     int unp_size;

  608.     int bits, stereo;

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

  610. 

  611.     if (buf_size <= 4) {

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

  613.         return AVERROR(EINVAL);

  614.     }

  615. 

  616.     unp_size = AV_RL32(buf);

  617. 

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

  619. 

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

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

  622.         *got_frame_ptr = 0;

  623.         return 1;

  624.     }

  625.     stereo = get_bits1(&gb);

  626.     bits = get_bits1(&gb);

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

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

  629.         return AVERROR(EINVAL);

  630.     }

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

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

  633.         return AVERROR(EINVAL);

  634.     }

  635. 

  636.     /* get output buffer */

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

  638.     if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {

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

  640.         return ret;

  641.     }

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

  643.     samples8 =            s->frame.data[0];

  644. 

  645.     // Initialize

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

  647.         h[i].length = 256;

  648.         h[i].maxlength = 0;

  649.         h[i].current = 0;

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

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

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

  653.         skip_bits1(&gb);

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

  655.         skip_bits1(&gb);

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

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

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

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

  660.             if(res < 0) {

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

  662.                 return -1;

  663.             }

  664.         }

  665.     }

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

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

  668.             pred[i] = sign_extend(av_bswap16(get_bits(&gb, 16)), 16);

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

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

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

  672.             if(get_bits_left(&gb)<0)

  673.                 return -1;

  674.             if(i & stereo) {

  675.                 if(vlc[2].table)

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

  677.                 else

  678.                     res = 0;

  679.                 if (res < 0) {

  680.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  681.                     return AVERROR_INVALIDDATA;

  682.                 }

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

  684.                 if(vlc[3].table)

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

  686.                 else

  687.                     res = 0;

  688.                 if (res < 0) {

  689.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  690.                     return AVERROR_INVALIDDATA;

  691.                 }

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

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

  694.                 *samples++ = av_clip_int16(pred[1]);

  695.             } else {

  696.                 if(vlc[0].table)

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

  698.                 else

  699.                     res = 0;

  700.                 if (res < 0) {

  701.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  702.                     return AVERROR_INVALIDDATA;

  703.                 }

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

  705.                 if(vlc[1].table)

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

  707.                 else

  708.                     res = 0;

  709.                 if (res < 0) {

  710.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  711.                     return AVERROR_INVALIDDATA;

  712.                 }

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

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

  715.                 *samples++ = av_clip_int16(pred[0]);

  716.             }

  717.         }

  718.     } else { //8-bit data

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

  720.             pred[i] = get_bits(&gb, 8);

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

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

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

  724.             if(get_bits_left(&gb)<0)

  725.                 return -1;

  726.             if(i & stereo){

  727.                 if(vlc[1].table)

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

  729.                 else

  730.                     res = 0;

  731.                 if (res < 0) {

  732.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  733.                     return AVERROR_INVALIDDATA;

  734.                 }

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

  736.                 *samples8++ = av_clip_uint8(pred[1]);

  737.             } else {

  738.                 if(vlc[0].table)

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

  740.                 else

  741.                     res = 0;

  742.                 if (res < 0) {

  743.                     av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");

  744.                     return AVERROR_INVALIDDATA;

  745.                 }

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

  747.                 *samples8++ = av_clip_uint8(pred[0]);

  748.             }

  749.         }

  750.     }

  751. 

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

  753.         if(vlc[i].table)

  754.             ff_free_vlc(&vlc[i]);

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

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

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

  758.     }

  759. 

  760.     *got_frame_ptr   = 1;

  761.     *(AVFrame *)data = s->frame;

  762. 

  763.     return buf_size;

  764. }

  765. 

  766. AVCodec ff_smacker_decoder = {

  767.     .name           = "smackvid",

  768.     .type           = AVMEDIA_TYPE_VIDEO,

  769.     .id             = CODEC_ID_SMACKVIDEO,

  770.     .priv_data_size = sizeof(SmackVContext),

  771.     .init           = decode_init,

  772.     .close          = decode_end,

  773.     .decode         = decode_frame,

  774.     .capabilities   = CODEC_CAP_DR1,

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

  776. };

  777. 

  778. AVCodec ff_smackaud_decoder = {

  779.     .name           = "smackaud",

  780.     .type           = AVMEDIA_TYPE_AUDIO,

  781.     .id             = CODEC_ID_SMACKAUDIO,

  782.     .priv_data_size = sizeof(SmackerAudioContext),

  783.     .init           = smka_decode_init,

  784.     .decode         = smka_decode_frame,

  785.     .capabilities   = CODEC_CAP_DR1,

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

  787. };