smacker.c
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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 
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 "internal.h"
36 #include "libavutil/audioconvert.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 {
52 
54  int mmap_last[3], mclr_last[3], full_last[3], type_last[3];
56 
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 
93  SMK_BLK_FILL = 3 };
94 
98 static int smacker_decode_tree(GetBitContext *gb, HuffContext *hc, uint32_t prefix, int length)
99 {
100  if(!get_bits1(gb)){ //Leaf
101  if(hc->current >= 256){
102  av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");
103  return -1;
104  }
105  if(length){
106  hc->bits[hc->current] = prefix;
107  hc->lengths[hc->current] = length;
108  } else {
109  hc->bits[hc->current] = 0;
110  hc->lengths[hc->current] = 0;
111  }
112  hc->values[hc->current] = get_bits(gb, 8);
113  hc->current++;
114  if(hc->maxlength < length)
115  hc->maxlength = length;
116  return 0;
117  } else { //Node
118  int r;
119  length++;
120  r = smacker_decode_tree(gb, hc, prefix, length);
121  if(r)
122  return r;
123  return smacker_decode_tree(gb, hc, prefix | (1 << (length - 1)), length);
124  }
125 }
126 
131 {
132  if (hc->current + 1 >= hc->length) {
133  av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");
134  return -1;
135  }
136  if(!get_bits1(gb)){ //Leaf
137  int val, i1, i2, b1, b2;
138  b1 = get_bits_count(gb);
139  i1 = ctx->v1->table ? get_vlc2(gb, ctx->v1->table, SMKTREE_BITS, 3) : 0;
140  b1 = get_bits_count(gb) - b1;
141  b2 = get_bits_count(gb);
142  i2 = ctx->v2->table ? get_vlc2(gb, ctx->v2->table, SMKTREE_BITS, 3) : 0;
143  b2 = get_bits_count(gb) - b2;
144  if (i1 < 0 || i2 < 0)
145  return -1;
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 
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];
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 -1;
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  memset(&vlc[0], 0, sizeof(VLC));
209  memset(&vlc[1], 0, sizeof(VLC));
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) + 4;
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 (ctx.last[0] >= huff.length ||
268  ctx.last[1] >= huff.length ||
269  ctx.last[2] >= huff.length) {
270  av_log(smk->avctx, AV_LOG_ERROR, "Huffman codes out of range\n");
271  err = AVERROR_INVALIDDATA;
272  }
273 
274  *recodes = huff.values;
275 
276  if(vlc[0].table)
277  ff_free_vlc(&vlc[0]);
278  if(vlc[1].table)
279  ff_free_vlc(&vlc[1]);
280  av_free(tmp1.bits);
281  av_free(tmp1.lengths);
282  av_free(tmp1.values);
283  av_free(tmp2.bits);
284  av_free(tmp2.lengths);
285  av_free(tmp2.values);
286 
287  return err;
288 }
289 
291  GetBitContext gb;
292  int mmap_size, mclr_size, full_size, type_size;
293 
294  mmap_size = AV_RL32(smk->avctx->extradata);
295  mclr_size = AV_RL32(smk->avctx->extradata + 4);
296  full_size = AV_RL32(smk->avctx->extradata + 8);
297  type_size = AV_RL32(smk->avctx->extradata + 12);
298 
299  init_get_bits(&gb, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);
300 
301  if(!get_bits1(&gb)) {
302  av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");
303  smk->mmap_tbl = av_malloc(sizeof(int) * 2);
304  smk->mmap_tbl[0] = 0;
305  smk->mmap_last[0] = smk->mmap_last[1] = smk->mmap_last[2] = 1;
306  } else {
307  if (smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size))
308  return -1;
309  }
310  if(!get_bits1(&gb)) {
311  av_log(smk->avctx, AV_LOG_INFO, "Skipping MCLR tree\n");
312  smk->mclr_tbl = av_malloc(sizeof(int) * 2);
313  smk->mclr_tbl[0] = 0;
314  smk->mclr_last[0] = smk->mclr_last[1] = smk->mclr_last[2] = 1;
315  } else {
316  if (smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size))
317  return -1;
318  }
319  if(!get_bits1(&gb)) {
320  av_log(smk->avctx, AV_LOG_INFO, "Skipping FULL tree\n");
321  smk->full_tbl = av_malloc(sizeof(int) * 2);
322  smk->full_tbl[0] = 0;
323  smk->full_last[0] = smk->full_last[1] = smk->full_last[2] = 1;
324  } else {
325  if (smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size))
326  return -1;
327  }
328  if(!get_bits1(&gb)) {
329  av_log(smk->avctx, AV_LOG_INFO, "Skipping TYPE tree\n");
330  smk->type_tbl = av_malloc(sizeof(int) * 2);
331  smk->type_tbl[0] = 0;
332  smk->type_last[0] = smk->type_last[1] = smk->type_last[2] = 1;
333  } else {
334  if (smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size))
335  return -1;
336  }
337 
338  return 0;
339 }
340 
341 static av_always_inline void last_reset(int *recode, int *last) {
342  recode[last[0]] = recode[last[1]] = recode[last[2]] = 0;
343 }
344 
345 /* get code and update history */
346 static av_always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {
347  register int *table = recode;
348  int v, b;
349 
350  b = get_bits_count(gb);
351  while(*table & SMK_NODE) {
352  if(get_bits1(gb))
353  table += (*table) & (~SMK_NODE);
354  table++;
355  }
356  v = *table;
357  b = get_bits_count(gb) - b;
358 
359  if(v != recode[last[0]]) {
360  recode[last[2]] = recode[last[1]];
361  recode[last[1]] = recode[last[0]];
362  recode[last[0]] = v;
363  }
364  return v;
365 }
366 
367 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
368 {
369  const uint8_t *buf = avpkt->data;
370  int buf_size = avpkt->size;
371  SmackVContext * const smk = avctx->priv_data;
372  uint8_t *out;
373  uint32_t *pal;
374  GetBitContext gb;
375  int blocks, blk, bw, bh;
376  int i;
377  int stride;
378 
379  if(buf_size <= 769)
380  return 0;
381 
382  smk->pic.reference = 1;
384  if(avctx->reget_buffer(avctx, &smk->pic) < 0){
385  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
386  return -1;
387  }
388 
389  /* make the palette available on the way out */
390  pal = (uint32_t*)smk->pic.data[1];
391  smk->pic.palette_has_changed = buf[0] & 1;
392  smk->pic.key_frame = !!(buf[0] & 2);
393  if(smk->pic.key_frame)
395  else
397 
398  buf++;
399  for(i = 0; i < 256; i++)
400  *pal++ = bytestream_get_be24(&buf);
401  buf_size -= 769;
402 
403  last_reset(smk->mmap_tbl, smk->mmap_last);
404  last_reset(smk->mclr_tbl, smk->mclr_last);
405  last_reset(smk->full_tbl, smk->full_last);
406  last_reset(smk->type_tbl, smk->type_last);
407  init_get_bits(&gb, buf, buf_size * 8);
408 
409  blk = 0;
410  bw = avctx->width >> 2;
411  bh = avctx->height >> 2;
412  blocks = bw * bh;
413  out = smk->pic.data[0];
414  stride = smk->pic.linesize[0];
415  while(blk < blocks) {
416  int type, run, mode;
417  uint16_t pix;
418 
419  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
420  run = block_runs[(type >> 2) & 0x3F];
421  switch(type & 3){
422  case SMK_BLK_MONO:
423  while(run-- && blk < blocks){
424  int clr, map;
425  int hi, lo;
426  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
427  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
428  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
429  hi = clr >> 8;
430  lo = clr & 0xFF;
431  for(i = 0; i < 4; i++) {
432  if(map & 1) out[0] = hi; else out[0] = lo;
433  if(map & 2) out[1] = hi; else out[1] = lo;
434  if(map & 4) out[2] = hi; else out[2] = lo;
435  if(map & 8) out[3] = hi; else out[3] = lo;
436  map >>= 4;
437  out += stride;
438  }
439  blk++;
440  }
441  break;
442  case SMK_BLK_FULL:
443  mode = 0;
444  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
445  if(get_bits1(&gb)) mode = 1;
446  else if(get_bits1(&gb)) mode = 2;
447  }
448  while(run-- && blk < blocks){
449  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
450  switch(mode){
451  case 0:
452  for(i = 0; i < 4; i++) {
453  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
454  AV_WL16(out+2,pix);
455  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
456  AV_WL16(out,pix);
457  out += stride;
458  }
459  break;
460  case 1:
461  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
462  out[0] = out[1] = pix & 0xFF;
463  out[2] = out[3] = pix >> 8;
464  out += stride;
465  out[0] = out[1] = pix & 0xFF;
466  out[2] = out[3] = pix >> 8;
467  out += stride;
468  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
469  out[0] = out[1] = pix & 0xFF;
470  out[2] = out[3] = pix >> 8;
471  out += stride;
472  out[0] = out[1] = pix & 0xFF;
473  out[2] = out[3] = pix >> 8;
474  out += stride;
475  break;
476  case 2:
477  for(i = 0; i < 2; i++) {
478  uint16_t pix1, pix2;
479  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
480  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
481  AV_WL16(out,pix1);
482  AV_WL16(out+2,pix2);
483  out += stride;
484  AV_WL16(out,pix1);
485  AV_WL16(out+2,pix2);
486  out += stride;
487  }
488  break;
489  }
490  blk++;
491  }
492  break;
493  case SMK_BLK_SKIP:
494  while(run-- && blk < blocks)
495  blk++;
496  break;
497  case SMK_BLK_FILL:
498  mode = type >> 8;
499  while(run-- && blk < blocks){
500  uint32_t col;
501  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
502  col = mode * 0x01010101;
503  for(i = 0; i < 4; i++) {
504  *((uint32_t*)out) = col;
505  out += stride;
506  }
507  blk++;
508  }
509  break;
510  }
511 
512  }
513 
514  *data_size = sizeof(AVFrame);
515  *(AVFrame*)data = smk->pic;
516 
517  /* always report that the buffer was completely consumed */
518  return buf_size;
519 }
520 
521 
522 
523 /*
524  *
525  * Init smacker decoder
526  *
527  */
529 {
530  SmackVContext * const c = avctx->priv_data;
531 
532  c->avctx = avctx;
533 
534  avctx->pix_fmt = PIX_FMT_PAL8;
535 
536 
537  /* decode huffman trees from extradata */
538  if(avctx->extradata_size < 16){
539  av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");
540  return -1;
541  }
542 
543  if (decode_header_trees(c))
544  return -1;
545 
546  return 0;
547 }
548 
549 
550 
551 /*
552  *
553  * Uninit smacker decoder
554  *
555  */
557 {
558  SmackVContext * const smk = avctx->priv_data;
559 
560  av_freep(&smk->mmap_tbl);
561  av_freep(&smk->mclr_tbl);
562  av_freep(&smk->full_tbl);
563  av_freep(&smk->type_tbl);
564 
565  if (smk->pic.data[0])
566  avctx->release_buffer(avctx, &smk->pic);
567 
568  return 0;
569 }
570 
571 
572 typedef struct SmackerAudioContext {
575 
577 {
578  SmackerAudioContext *s = avctx->priv_data;
579 
580  if (avctx->channels < 1 || avctx->channels > 2) {
581  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
582  return AVERROR(EINVAL);
583  }
586 
588  avctx->coded_frame = &s->frame;
589 
590  return 0;
591 }
592 
596 static int smka_decode_frame(AVCodecContext *avctx, void *data,
597  int *got_frame_ptr, AVPacket *avpkt)
598 {
599  SmackerAudioContext *s = avctx->priv_data;
600  const uint8_t *buf = avpkt->data;
601  int buf_size = avpkt->size;
602  GetBitContext gb;
603  HuffContext h[4];
604  VLC vlc[4];
605  int16_t *samples;
606  uint8_t *samples8;
607  int val;
608  int i, res, ret;
609  int unp_size;
610  int bits, stereo;
611  int pred[2] = {0, 0};
612 
613  if (buf_size <= 4) {
614  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
615  return AVERROR(EINVAL);
616  }
617 
618  unp_size = AV_RL32(buf);
619 
620  init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
621 
622  if(!get_bits1(&gb)){
623  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
624  *got_frame_ptr = 0;
625  return 1;
626  }
627  stereo = get_bits1(&gb);
628  bits = get_bits1(&gb);
629  if (stereo ^ (avctx->channels != 1)) {
630  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
631  return AVERROR(EINVAL);
632  }
633  if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {
634  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
635  return AVERROR(EINVAL);
636  }
637 
638  /* get output buffer */
639  s->frame.nb_samples = unp_size / (avctx->channels * (bits + 1));
640  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
641  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
642  return ret;
643  }
644  samples = (int16_t *)s->frame.data[0];
645  samples8 = s->frame.data[0];
646 
647  memset(vlc, 0, sizeof(VLC) * 4);
648  memset(h, 0, sizeof(HuffContext) * 4);
649  // Initialize
650  for(i = 0; i < (1 << (bits + stereo)); i++) {
651  h[i].length = 256;
652  h[i].maxlength = 0;
653  h[i].current = 0;
654  h[i].bits = av_mallocz(256 * 4);
655  h[i].lengths = av_mallocz(256 * sizeof(int));
656  h[i].values = av_mallocz(256 * sizeof(int));
657  skip_bits1(&gb);
658  if (smacker_decode_tree(&gb, &h[i], 0, 0) < 0) {
659  for (; i >= 0; i--) {
660  if (vlc[i].table)
661  ff_free_vlc(&vlc[i]);
662  av_free(h[i].bits);
663  av_free(h[i].lengths);
664  av_free(h[i].values);
665  }
666  return AVERROR_INVALIDDATA;
667  }
668  skip_bits1(&gb);
669  if(h[i].current > 1) {
670  res = init_vlc(&vlc[i], SMKTREE_BITS, h[i].length,
671  h[i].lengths, sizeof(int), sizeof(int),
672  h[i].bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
673  if(res < 0) {
674  av_log(avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
675  return -1;
676  }
677  }
678  }
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(i & stereo) {
686  if(vlc[2].table)
687  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
688  else
689  res = 0;
690  val = h[2].values[res];
691  if(vlc[3].table)
692  res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);
693  else
694  res = 0;
695  val |= h[3].values[res] << 8;
696  pred[1] += sign_extend(val, 16);
697  *samples++ = av_clip_int16(pred[1]);
698  } else {
699  if(vlc[0].table)
700  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
701  else
702  res = 0;
703  val = h[0].values[res];
704  if(vlc[1].table)
705  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
706  else
707  res = 0;
708  val |= h[1].values[res] << 8;
709  pred[0] += sign_extend(val, 16);
710  *samples++ = av_clip_int16(pred[0]);
711  }
712  }
713  } else { //8-bit data
714  for(i = stereo; i >= 0; i--)
715  pred[i] = get_bits(&gb, 8);
716  for(i = 0; i <= stereo; i++)
717  *samples8++ = pred[i];
718  for(; i < unp_size; i++) {
719  if(i & stereo){
720  if(vlc[1].table)
721  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
722  else
723  res = 0;
724  pred[1] += sign_extend(h[1].values[res], 8);
725  *samples8++ = av_clip_uint8(pred[1]);
726  } else {
727  if(vlc[0].table)
728  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
729  else
730  res = 0;
731  pred[0] += sign_extend(h[0].values[res], 8);
732  *samples8++ = av_clip_uint8(pred[0]);
733  }
734  }
735  }
736 
737  for(i = 0; i < 4; i++) {
738  if(vlc[i].table)
739  ff_free_vlc(&vlc[i]);
740  av_free(h[i].bits);
741  av_free(h[i].lengths);
742  av_free(h[i].values);
743  }
744 
745  *got_frame_ptr = 1;
746  *(AVFrame *)data = s->frame;
747 
748  return buf_size;
749 }
750 
752  .name = "smackvid",
753  .type = AVMEDIA_TYPE_VIDEO,
754  .id = CODEC_ID_SMACKVIDEO,
755  .priv_data_size = sizeof(SmackVContext),
756  .init = decode_init,
757  .close = decode_end,
758  .decode = decode_frame,
759  .capabilities = CODEC_CAP_DR1,
760  .long_name = NULL_IF_CONFIG_SMALL("Smacker video"),
761 };
762 
764  .name = "smackaud",
765  .type = AVMEDIA_TYPE_AUDIO,
766  .id = CODEC_ID_SMACKAUDIO,
767  .priv_data_size = sizeof(SmackerAudioContext),
770  .capabilities = CODEC_CAP_DR1,
771  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
772 };
773