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smacker.c
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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) + 3;
261  huff.maxlength = 0;
262  huff.current = 0;
263  huff.values = av_mallocz(huff.length * sizeof(int));
264 
265  if (smacker_decode_bigtree(gb, &huff, &ctx) < 0)
266  err = -1;
267  skip_bits1(gb);
268  if(ctx.last[0] == -1) ctx.last[0] = huff.current++;
269  if(ctx.last[1] == -1) ctx.last[1] = huff.current++;
270  if(ctx.last[2] == -1) ctx.last[2] = huff.current++;
271  if(huff.current > huff.length){
272  ctx.last[0] = ctx.last[1] = ctx.last[2] = 1;
273  av_log(smk->avctx, AV_LOG_ERROR, "bigtree damaged\n");
274  return AVERROR_INVALIDDATA;
275  }
276 
277  *recodes = huff.values;
278 
279  if(vlc[0].table)
280  ff_free_vlc(&vlc[0]);
281  if(vlc[1].table)
282  ff_free_vlc(&vlc[1]);
283  av_free(tmp1.bits);
284  av_free(tmp1.lengths);
285  av_free(tmp1.values);
286  av_free(tmp2.bits);
287  av_free(tmp2.lengths);
288  av_free(tmp2.values);
289 
290  return err;
291 }
292 
293 static int decode_header_trees(SmackVContext *smk) {
294  GetBitContext gb;
295  int mmap_size, mclr_size, full_size, type_size;
296 
297  mmap_size = AV_RL32(smk->avctx->extradata);
298  mclr_size = AV_RL32(smk->avctx->extradata + 4);
299  full_size = AV_RL32(smk->avctx->extradata + 8);
300  type_size = AV_RL32(smk->avctx->extradata + 12);
301 
302  init_get_bits(&gb, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);
303 
304  if(!get_bits1(&gb)) {
305  av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");
306  smk->mmap_tbl = av_malloc(sizeof(int) * 2);
307  smk->mmap_tbl[0] = 0;
308  smk->mmap_last[0] = smk->mmap_last[1] = smk->mmap_last[2] = 1;
309  } else {
310  if (smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size))
311  return AVERROR_INVALIDDATA;
312  }
313  if(!get_bits1(&gb)) {
314  av_log(smk->avctx, AV_LOG_INFO, "Skipping MCLR tree\n");
315  smk->mclr_tbl = av_malloc(sizeof(int) * 2);
316  smk->mclr_tbl[0] = 0;
317  smk->mclr_last[0] = smk->mclr_last[1] = smk->mclr_last[2] = 1;
318  } else {
319  if (smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size))
320  return AVERROR_INVALIDDATA;
321  }
322  if(!get_bits1(&gb)) {
323  av_log(smk->avctx, AV_LOG_INFO, "Skipping FULL tree\n");
324  smk->full_tbl = av_malloc(sizeof(int) * 2);
325  smk->full_tbl[0] = 0;
326  smk->full_last[0] = smk->full_last[1] = smk->full_last[2] = 1;
327  } else {
328  if (smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size))
329  return AVERROR_INVALIDDATA;
330  }
331  if(!get_bits1(&gb)) {
332  av_log(smk->avctx, AV_LOG_INFO, "Skipping TYPE tree\n");
333  smk->type_tbl = av_malloc(sizeof(int) * 2);
334  smk->type_tbl[0] = 0;
335  smk->type_last[0] = smk->type_last[1] = smk->type_last[2] = 1;
336  } else {
337  if (smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size))
338  return AVERROR_INVALIDDATA;
339  }
340 
341  return 0;
342 }
343 
344 static av_always_inline void last_reset(int *recode, int *last) {
345  recode[last[0]] = recode[last[1]] = recode[last[2]] = 0;
346 }
347 
348 /* get code and update history */
349 static av_always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {
350  register int *table = recode;
351  int v;
352 
353  while(*table & SMK_NODE) {
354  if(get_bits1(gb))
355  table += (*table) & (~SMK_NODE);
356  table++;
357  }
358  v = *table;
359 
360  if(v != recode[last[0]]) {
361  recode[last[2]] = recode[last[1]];
362  recode[last[1]] = recode[last[0]];
363  recode[last[0]] = v;
364  }
365  return v;
366 }
367 
368 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
369  AVPacket *avpkt)
370 {
371  SmackVContext * const smk = avctx->priv_data;
372  uint8_t *out;
373  uint32_t *pal;
374  GetByteContext gb2;
375  GetBitContext gb;
376  int blocks, blk, bw, bh;
377  int i, ret;
378  int stride;
379  int flags;
380 
381  if (avpkt->size <= 769)
382  return AVERROR_INVALIDDATA;
383 
384  smk->pic.reference = 3;
385  smk->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
386  if((ret = avctx->reget_buffer(avctx, &smk->pic)) < 0){
387  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
388  return ret;
389  }
390 
391  /* make the palette available on the way out */
392  pal = (uint32_t*)smk->pic.data[1];
393  bytestream2_init(&gb2, avpkt->data, avpkt->size);
394  flags = bytestream2_get_byteu(&gb2);
395  smk->pic.palette_has_changed = flags & 1;
396  smk->pic.key_frame = !!(flags & 2);
397  if(smk->pic.key_frame)
398  smk->pic.pict_type = AV_PICTURE_TYPE_I;
399  else
400  smk->pic.pict_type = AV_PICTURE_TYPE_P;
401 
402  for(i = 0; i < 256; i++)
403  *pal++ = 0xFFU << 24 | bytestream2_get_be24u(&gb2);
404 
405  last_reset(smk->mmap_tbl, smk->mmap_last);
406  last_reset(smk->mclr_tbl, smk->mclr_last);
407  last_reset(smk->full_tbl, smk->full_last);
408  last_reset(smk->type_tbl, smk->type_last);
409  init_get_bits(&gb, avpkt->data + 769, (avpkt->size - 769) * 8);
410 
411  blk = 0;
412  bw = avctx->width >> 2;
413  bh = avctx->height >> 2;
414  blocks = bw * bh;
415  out = smk->pic.data[0];
416  stride = smk->pic.linesize[0];
417  while(blk < blocks) {
418  int type, run, mode;
419  uint16_t pix;
420 
421  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
422  run = block_runs[(type >> 2) & 0x3F];
423  switch(type & 3){
424  case SMK_BLK_MONO:
425  while(run-- && blk < blocks){
426  int clr, map;
427  int hi, lo;
428  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
429  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
430  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
431  hi = clr >> 8;
432  lo = clr & 0xFF;
433  for(i = 0; i < 4; i++) {
434  if(map & 1) out[0] = hi; else out[0] = lo;
435  if(map & 2) out[1] = hi; else out[1] = lo;
436  if(map & 4) out[2] = hi; else out[2] = lo;
437  if(map & 8) out[3] = hi; else out[3] = lo;
438  map >>= 4;
439  out += stride;
440  }
441  blk++;
442  }
443  break;
444  case SMK_BLK_FULL:
445  mode = 0;
446  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
447  if(get_bits1(&gb)) mode = 1;
448  else if(get_bits1(&gb)) mode = 2;
449  }
450  while(run-- && blk < blocks){
451  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
452  switch(mode){
453  case 0:
454  for(i = 0; i < 4; i++) {
455  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
456  AV_WL16(out+2,pix);
457  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
458  AV_WL16(out,pix);
459  out += stride;
460  }
461  break;
462  case 1:
463  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
464  out[0] = out[1] = pix & 0xFF;
465  out[2] = out[3] = pix >> 8;
466  out += stride;
467  out[0] = out[1] = pix & 0xFF;
468  out[2] = out[3] = pix >> 8;
469  out += stride;
470  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
471  out[0] = out[1] = pix & 0xFF;
472  out[2] = out[3] = pix >> 8;
473  out += stride;
474  out[0] = out[1] = pix & 0xFF;
475  out[2] = out[3] = pix >> 8;
476  out += stride;
477  break;
478  case 2:
479  for(i = 0; i < 2; i++) {
480  uint16_t pix1, pix2;
481  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
482  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
483  AV_WL16(out,pix1);
484  AV_WL16(out+2,pix2);
485  out += stride;
486  AV_WL16(out,pix1);
487  AV_WL16(out+2,pix2);
488  out += stride;
489  }
490  break;
491  }
492  blk++;
493  }
494  break;
495  case SMK_BLK_SKIP:
496  while(run-- && blk < blocks)
497  blk++;
498  break;
499  case SMK_BLK_FILL:
500  mode = type >> 8;
501  while(run-- && blk < blocks){
502  uint32_t col;
503  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
504  col = mode * 0x01010101;
505  for(i = 0; i < 4; i++) {
506  *((uint32_t*)out) = col;
507  out += stride;
508  }
509  blk++;
510  }
511  break;
512  }
513 
514  }
515 
516  *got_frame = 1;
517  *(AVFrame*)data = smk->pic;
518 
519  /* always report that the buffer was completely consumed */
520  return avpkt->size;
521 }
522 
523 
524 
525 /*
526  *
527  * Init smacker decoder
528  *
529  */
530 static av_cold int decode_init(AVCodecContext *avctx)
531 {
532  SmackVContext * const c = avctx->priv_data;
533 
534  c->avctx = avctx;
535 
536  avctx->pix_fmt = AV_PIX_FMT_PAL8;
537 
538  avcodec_get_frame_defaults(&c->pic);
539 
540  /* decode huffman trees from extradata */
541  if(avctx->extradata_size < 16){
542  av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");
543  return AVERROR(EINVAL);
544  }
545 
546  if (decode_header_trees(c))
547  return AVERROR_INVALIDDATA;
548 
549  return 0;
550 }
551 
552 
553 
554 /*
555  *
556  * Uninit smacker decoder
557  *
558  */
559 static av_cold int decode_end(AVCodecContext *avctx)
560 {
561  SmackVContext * const smk = avctx->priv_data;
562 
563  av_freep(&smk->mmap_tbl);
564  av_freep(&smk->mclr_tbl);
565  av_freep(&smk->full_tbl);
566  av_freep(&smk->type_tbl);
567 
568  if (smk->pic.data[0])
569  avctx->release_buffer(avctx, &smk->pic);
570 
571  return 0;
572 }
573 
574 
575 typedef struct SmackerAudioContext {
576  AVFrame frame;
577 } SmackerAudioContext;
578 
579 static av_cold int smka_decode_init(AVCodecContext *avctx)
580 {
581  SmackerAudioContext *s = avctx->priv_data;
582 
583  if (avctx->channels < 1 || avctx->channels > 2) {
584  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
585  return AVERROR(EINVAL);
586  }
587  avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
588  avctx->sample_fmt = avctx->bits_per_coded_sample == 8 ? AV_SAMPLE_FMT_U8 : AV_SAMPLE_FMT_S16;
589 
590  avcodec_get_frame_defaults(&s->frame);
591  avctx->coded_frame = &s->frame;
592 
593  return 0;
594 }
595 
596 /**
597  * Decode Smacker audio data
598  */
599 static int smka_decode_frame(AVCodecContext *avctx, void *data,
600  int *got_frame_ptr, AVPacket *avpkt)
601 {
602  SmackerAudioContext *s = avctx->priv_data;
603  const uint8_t *buf = avpkt->data;
604  int buf_size = avpkt->size;
605  GetBitContext gb;
606  HuffContext h[4] = { { 0 } };
607  VLC vlc[4] = { { 0 } };
608  int16_t *samples;
609  uint8_t *samples8;
610  int val;
611  int i, res, ret;
612  int unp_size;
613  int bits, stereo;
614  int pred[2] = {0, 0};
615 
616  if (buf_size <= 4) {
617  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
618  return AVERROR(EINVAL);
619  }
620 
621  unp_size = AV_RL32(buf);
622 
623  if (unp_size > (1U<<24)) {
624  av_log(avctx, AV_LOG_ERROR, "packet is too big\n");
625  return AVERROR_INVALIDDATA;
626  }
627 
628  init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
629 
630  if(!get_bits1(&gb)){
631  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
632  *got_frame_ptr = 0;
633  return 1;
634  }
635  stereo = get_bits1(&gb);
636  bits = get_bits1(&gb);
637  if (stereo ^ (avctx->channels != 1)) {
638  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
639  return AVERROR(EINVAL);
640  }
641  if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {
642  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
643  return AVERROR(EINVAL);
644  }
645 
646  /* get output buffer */
647  s->frame.nb_samples = unp_size / (avctx->channels * (bits + 1));
648  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
649  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
650  return ret;
651  }
652  samples = (int16_t *)s->frame.data[0];
653  samples8 = s->frame.data[0];
654 
655  // Initialize
656  for(i = 0; i < (1 << (bits + stereo)); i++) {
657  h[i].length = 256;
658  h[i].maxlength = 0;
659  h[i].current = 0;
660  h[i].bits = av_mallocz(256 * 4);
661  h[i].lengths = av_mallocz(256 * sizeof(int));
662  h[i].values = av_mallocz(256 * sizeof(int));
663  skip_bits1(&gb);
664  res = smacker_decode_tree(&gb, &h[i], 0, 0);
665  if (res < 0)
666  return res;
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  if(bits) { //decode 16-bit data
679  for(i = stereo; i >= 0; i--)
680  pred[i] = sign_extend(av_bswap16(get_bits(&gb, 16)), 16);
681  for(i = 0; i <= stereo; i++)
682  *samples++ = pred[i];
683  for(; i < unp_size / 2; i++) {
684  if(get_bits_left(&gb)<0)
685  return AVERROR_INVALIDDATA;
686  if(i & stereo) {
687  if(vlc[2].table)
688  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
689  else
690  res = 0;
691  if (res < 0) {
692  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
693  return AVERROR_INVALIDDATA;
694  }
695  val = h[2].values[res];
696  if(vlc[3].table)
697  res = get_vlc2(&gb, vlc[3].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[3].values[res] << 8;
705  pred[1] += sign_extend(val, 16);
706  *samples++ = pred[1];
707  } else {
708  if(vlc[0].table)
709  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
710  else
711  res = 0;
712  if (res < 0) {
713  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
714  return AVERROR_INVALIDDATA;
715  }
716  val = h[0].values[res];
717  if(vlc[1].table)
718  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
719  else
720  res = 0;
721  if (res < 0) {
722  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
723  return AVERROR_INVALIDDATA;
724  }
725  val |= h[1].values[res] << 8;
726  pred[0] += sign_extend(val, 16);
727  *samples++ = pred[0];
728  }
729  }
730  } else { //8-bit data
731  for(i = stereo; i >= 0; i--)
732  pred[i] = get_bits(&gb, 8);
733  for(i = 0; i <= stereo; i++)
734  *samples8++ = pred[i];
735  for(; i < unp_size; i++) {
736  if(get_bits_left(&gb)<0)
737  return AVERROR_INVALIDDATA;
738  if(i & stereo){
739  if(vlc[1].table)
740  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
741  else
742  res = 0;
743  if (res < 0) {
744  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
745  return AVERROR_INVALIDDATA;
746  }
747  pred[1] += sign_extend(h[1].values[res], 8);
748  *samples8++ = av_clip_uint8(pred[1]);
749  } else {
750  if(vlc[0].table)
751  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
752  else
753  res = 0;
754  if (res < 0) {
755  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
756  return AVERROR_INVALIDDATA;
757  }
758  pred[0] += sign_extend(h[0].values[res], 8);
759  *samples8++ = av_clip_uint8(pred[0]);
760  }
761  }
762  }
763 
764  for(i = 0; i < 4; i++) {
765  if(vlc[i].table)
766  ff_free_vlc(&vlc[i]);
767  av_free(h[i].bits);
768  av_free(h[i].lengths);
769  av_free(h[i].values);
770  }
771 
772  *got_frame_ptr = 1;
773  *(AVFrame *)data = s->frame;
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  .priv_data_size = sizeof(SmackerAudioContext),
795  .init = smka_decode_init,
796  .decode = smka_decode_frame,
797  .capabilities = CODEC_CAP_DR1,
798  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
799 };
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