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.
54268 Commits
32 Branches
283MB
Tree: 90bd75e6eb
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '90bd75e6eb'
${ noResults }
FFmpeg/libavcodec/smacker.c

799 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 "libavutil/channel_layout.h"

  35. #include "avcodec.h"

  36. #include "internal.h"

  37. #include "mathops.h"

  38. 

  39. #define BITSTREAM_READER_LE

  40. #include "get_bits.h"

  41. #include "bytestream.h"

  42. 

  43. #define SMKTREE_BITS 9

  44. #define SMK_NODE 0x80000000

  45. 

  46. /*

  47.  * Decoder context

  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(GetBitContext *gb, HuffContext *hc, uint32_t prefix, int length)

  99. {

  100.     if(length > 32 || length > 3*SMKTREE_BITS) {

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

  102.         return AVERROR_INVALIDDATA;

  103.     }

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

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

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

  107.             return AVERROR_INVALIDDATA;

  108.         }

  109.         if(length){

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

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

  112.         } else {

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

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

  115.         }

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

  117.         hc->current++;

  118.         if(hc->maxlength < length)

  119.             hc->maxlength = length;

  120.         return 0;

  121.     } else { //Node

  122.         int r;

  123.         length++;

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

  125.         if(r)

  126.             return r;

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

  128.     }

  129. }

  130. 

  131. /**

  132.  * Decode header tree

  133.  */

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

  135. {

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

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

  138.         return AVERROR_INVALIDDATA;

  139.     }

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

  141.         int val, i1, i2;

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

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

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

  145.             return AVERROR_INVALIDDATA;

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

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

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

  149.             val = 0;

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

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

  152.             val = 0;

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

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

  155.             val = 0;

  156.         }

  157. 

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

  159.         return 1;

  160.     } else { //Node

  161.         int r = 0, r_new, t;

  162. 

  163.         t = hc->current++;

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

  165.         if(r < 0)

  166.             return r;

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

  168.         r++;

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

  170.         if (r_new < 0)

  171.             return r_new;

  172.         return r + r_new;

  173.     }

  174. }

  175. 

  176. /**

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

  178.  */

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

  180. {

  181.     int res;

  182.     HuffContext huff;

  183.     HuffContext tmp1, tmp2;

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

  185.     int escapes[3];

  186.     DBCtx ctx;

  187.     int err = 0;

  188. 

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

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

  191.         return AVERROR_INVALIDDATA;

  192.     }

  193. 

  194.     tmp1.length = 256;

  195.     tmp1.maxlength = 0;

  196.     tmp1.current = 0;

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

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

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

  200. 

  201.     tmp2.length = 256;

  202.     tmp2.maxlength = 0;

  203.     tmp2.current = 0;

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

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

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

  207. 

  208.     if(get_bits1(gb)) {

  209.         res = smacker_decode_tree(gb, &tmp1, 0, 0);

  210.         if (res < 0)

  211.             return res;

  212.         skip_bits1(gb);

  213.         if(tmp1.current > 1) {

  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 AVERROR_INVALIDDATA;

  220.             }

  221.         }

  222.     }

  223.     if (!vlc[0].table) {

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

  225.     }

  226.     if(get_bits1(gb)){

  227.         res = smacker_decode_tree(gb, &tmp2, 0, 0);

  228.         if (res < 0)

  229.             return res;

  230.         skip_bits1(gb);

  231.         if(tmp2.current > 1) {

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

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

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

  235.             if(res < 0) {

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

  237.                 return AVERROR_INVALIDDATA;

  238.             }

  239.         }

  240.     }

  241.     if (!vlc[1].table) {

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

  243.     }

  244. 

  245.     escapes[0]  = get_bits(gb, 16);

  246.     escapes[1]  = get_bits(gb, 16);

  247.     escapes[2]  = get_bits(gb, 16);

  248. 

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

  250. 

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

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

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

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

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

  256.     ctx.recode1 = tmp1.values;

  257.     ctx.recode2 = tmp2.values;

  258.     ctx.last = last;

  259. 

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

  261.     huff.maxlength = 0;

  262.     huff.current = 0;

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

  264.     if (!huff.values)

  265.         return AVERROR(ENOMEM);

  266. 

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

  268.         err = -1;

  269.     skip_bits1(gb);

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

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

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

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

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

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

  276.         return AVERROR_INVALIDDATA;

  277.     }

  278. 

  279.     *recodes = huff.values;

  280. 

  281.     if(vlc[0].table)

  282.         ff_free_vlc(&vlc[0]);

  283.     if(vlc[1].table)

  284.         ff_free_vlc(&vlc[1]);

  285.     av_free(tmp1.bits);

  286.     av_free(tmp1.lengths);

  287.     av_free(tmp1.values);

  288.     av_free(tmp2.bits);

  289.     av_free(tmp2.lengths);

  290.     av_free(tmp2.values);

  291. 

  292.     return err;

  293. }

  294. 

  295. static int decode_header_trees(SmackVContext *smk) {

  296.     GetBitContext gb;

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

  298. 

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

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

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

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

  303. 

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

  305. 

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

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

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

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

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

  311.     } else {

  312.         ret = smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size);

  313.         if (ret < 0)

  314.             return ret;

  315.     }

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

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

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

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

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

  321.     } else {

  322.         ret = smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size);

  323.         if (ret < 0)

  324.             return ret;

  325.     }

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

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

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

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

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

  331.     } else {

  332.         ret = smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size);

  333.         if (ret < 0)

  334.             return ret;

  335.     }

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

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

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

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

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

  341.     } else {

  342.         ret = smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size);

  343.         if (ret < 0)

  344.             return ret;

  345.     }

  346. 

  347.     return 0;

  348. }

  349. 

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

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

  352. }

  353. 

  354. /* get code and update history */

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

  356.     register int *table = recode;

  357.     int v;

  358. 

  359.     while(*table & SMK_NODE) {

  360.         if(get_bits1(gb))

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

  362.         table++;

  363.     }

  364.     v = *table;

  365. 

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

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

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

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

  370.     }

  371.     return v;

  372. }

  373. 

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

  375.                         AVPacket *avpkt)

  376. {

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

  378.     uint8_t *out;

  379.     uint32_t *pal;

  380.     GetByteContext gb2;

  381.     GetBitContext gb;

  382.     int blocks, blk, bw, bh;

  383.     int i, ret;

  384.     int stride;

  385.     int flags;

  386. 

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

  388.         return AVERROR_INVALIDDATA;

  389. 

  390.     if ((ret = ff_reget_buffer(avctx, &smk->pic)) < 0)

  391.         return ret;

  392. 

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

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

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

  396.     flags = bytestream2_get_byteu(&gb2);

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

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

  399.     if(smk->pic.key_frame)

  400.         smk->pic.pict_type = AV_PICTURE_TYPE_I;

  401.     else

  402.         smk->pic.pict_type = AV_PICTURE_TYPE_P;

  403. 

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

  405.         *pal++ = 0xFFU << 24 | bytestream2_get_be24u(&gb2);

  406. 

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

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

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

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

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

  412. 

  413.     blk = 0;

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

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

  416.     blocks = bw * bh;

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

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

  419.     while(blk < blocks) {

  420.         int type, run, mode;

  421.         uint16_t pix;

  422. 

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

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

  425.         switch(type & 3){

  426.         case SMK_BLK_MONO:

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

  428.                 int clr, map;

  429.                 int hi, lo;

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

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

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

  433.                 hi = clr >> 8;

  434.                 lo = clr & 0xFF;

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

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

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

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

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

  440.                     map >>= 4;

  441.                     out += stride;

  442.                 }

  443.                 blk++;

  444.             }

  445.             break;

  446.         case SMK_BLK_FULL:

  447.             mode = 0;

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

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

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

  451.             }

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

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

  454.                 switch(mode){

  455.                 case 0:

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

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

  458.                         AV_WL16(out+2,pix);

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

  460.                         AV_WL16(out,pix);

  461.                         out += stride;

  462.                     }

  463.                     break;

  464.                 case 1:

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

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

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

  475.                     out += stride;

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

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

  478.                     out += stride;

  479.                     break;

  480.                 case 2:

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

  482.                         uint16_t pix1, pix2;

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

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

  485.                         AV_WL16(out,pix1);

  486.                         AV_WL16(out+2,pix2);

  487.                         out += stride;

  488.                         AV_WL16(out,pix1);

  489.                         AV_WL16(out+2,pix2);

  490.                         out += stride;

  491.                     }

  492.                     break;

  493.                 }

  494.                 blk++;

  495.             }

  496.             break;

  497.         case SMK_BLK_SKIP:

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

  499.                 blk++;

  500.             break;

  501.         case SMK_BLK_FILL:

  502.             mode = type >> 8;

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

  504.                 uint32_t col;

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

  506.                 col = mode * 0x01010101;

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

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

  509.                     out += stride;

  510.                 }

  511.                 blk++;

  512.             }

  513.             break;

  514.         }

  515. 

  516.     }

  517. 

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

  519.         return ret;

  520. 

  521.     *got_frame = 1;

  522. 

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

  524.     return avpkt->size;

  525. }

  526. 

  527. 

  528. 

  529. /*

  530.  *

  531.  * Init smacker decoder

  532.  *

  533.  */

  534. static av_cold int decode_init(AVCodecContext *avctx)

  535. {

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

  537.     int ret;

  538. 

  539.     c->avctx = avctx;

  540. 

  541.     avctx->pix_fmt = AV_PIX_FMT_PAL8;

  542.     avcodec_get_frame_defaults(&c->pic);

  543. 

  544.     /* decode huffman trees from extradata */

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

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

  547.         return AVERROR(EINVAL);

  548.     }

  549. 

  550.     ret = decode_header_trees(c);

  551.     if (ret < 0)

  552.         return ret;

  553. 

  554.     return 0;

  555. }

  556. 

  557. 

  558. 

  559. /*

  560.  *

  561.  * Uninit smacker decoder

  562.  *

  563.  */

  564. static av_cold int decode_end(AVCodecContext *avctx)

  565. {

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

  567. 

  568.     av_freep(&smk->mmap_tbl);

  569.     av_freep(&smk->mclr_tbl);

  570.     av_freep(&smk->full_tbl);

  571.     av_freep(&smk->type_tbl);

  572. 

  573.     av_frame_unref(&smk->pic);

  574. 

  575.     return 0;

  576. }

  577. 

  578. 

  579. static av_cold int smka_decode_init(AVCodecContext *avctx)

  580. {

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

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

  583.         return AVERROR(EINVAL);

  584.     }

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

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

  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.     AVFrame *frame     = 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.     if (unp_size > (1U<<24)) {

  619.         av_log(avctx, AV_LOG_ERROR, "packet is too big\n");

  620.         return AVERROR_INVALIDDATA;

  621.     }

  622. 

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

  624. 

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

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

  627.         *got_frame_ptr = 0;

  628.         return 1;

  629.     }

  630.     stereo = get_bits1(&gb);

  631.     bits = get_bits1(&gb);

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

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

  634.         return AVERROR(EINVAL);

  635.     }

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

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

  638.         return AVERROR(EINVAL);

  639.     }

  640. 

  641.     /* get output buffer */

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

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

  644.         return ret;

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

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

  647. 

  648.     // Initialize

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

  650.         h[i].length = 256;

  651.         h[i].maxlength = 0;

  652.         h[i].current = 0;

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

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

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

  656.         skip_bits1(&gb);

  657.         if (smacker_decode_tree(&gb, &h[i], 0, 0) < 0) {

  658.             for (; i >= 0; i--) {

  659.                 if (vlc[i].table)

  660.                     ff_free_vlc(&vlc[i]);

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

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

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

  664.             }

  665.             return AVERROR_INVALIDDATA;

  666.         }

  667.         skip_bits1(&gb);

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

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

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

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

  672.             if(res < 0) {

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

  674.                 return AVERROR_INVALIDDATA;

  675.             }

  676.         }

  677.     }

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

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

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

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

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

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

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

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

  686.                 return AVERROR_INVALIDDATA;

  687.             if(i & stereo) {

  688.                 if(vlc[2].table)

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

  690.                 else

  691.                     res = 0;

  692.                 if (res < 0) {

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

  694.                     return AVERROR_INVALIDDATA;

  695.                 }

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

  697.                 if(vlc[3].table)

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

  699.                 else

  700.                     res = 0;

  701.                 if (res < 0) {

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

  703.                     return AVERROR_INVALIDDATA;

  704.                 }

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

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

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

  708.             } else {

  709.                 if(vlc[0].table)

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

  711.                 else

  712.                     res = 0;

  713.                 if (res < 0) {

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

  715.                     return AVERROR_INVALIDDATA;

  716.                 }

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

  718.                 if(vlc[1].table)

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

  720.                 else

  721.                     res = 0;

  722.                 if (res < 0) {

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

  724.                     return AVERROR_INVALIDDATA;

  725.                 }

  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] = get_bits(&gb, 8);

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

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

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

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

  738.                 return AVERROR_INVALIDDATA;

  739.             if(i & stereo){

  740.                 if(vlc[1].table)

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

  742.                 else

  743.                     res = 0;

  744.                 if (res < 0) {

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

  746.                     return AVERROR_INVALIDDATA;

  747.                 }

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

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

  750.             } else {

  751.                 if(vlc[0].table)

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

  753.                 else

  754.                     res = 0;

  755.                 if (res < 0) {

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

  757.                     return AVERROR_INVALIDDATA;

  758.                 }

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

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

  761.             }

  762.         }

  763.     }

  764. 

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

  766.         if(vlc[i].table)

  767.             ff_free_vlc(&vlc[i]);

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

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

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

  771.     }

  772. 

  773.     *got_frame_ptr = 1;

  774. 

  775.     return buf_size;

  776. }

  777. 

  778. AVCodec ff_smacker_decoder = {

  779.     .name           = "smackvid",

  780.     .type           = AVMEDIA_TYPE_VIDEO,

  781.     .id             = AV_CODEC_ID_SMACKVIDEO,

  782.     .priv_data_size = sizeof(SmackVContext),

  783.     .init           = decode_init,

  784.     .close          = decode_end,

  785.     .decode         = decode_frame,

  786.     .capabilities   = CODEC_CAP_DR1,

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

  788. };

  789. 

  790. AVCodec ff_smackaud_decoder = {

  791.     .name           = "smackaud",

  792.     .type           = AVMEDIA_TYPE_AUDIO,

  793.     .id             = AV_CODEC_ID_SMACKAUDIO,

  794.     .init           = smka_decode_init,

  795.     .decode         = smka_decode_frame,

  796.     .capabilities   = CODEC_CAP_DR1,

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

  798. };