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 "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 {
51 
53  int mmap_last[3], mclr_last[3], full_last[3], type_last[3];
55 
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 
92  SMK_BLK_FILL = 3 };
93 
97 static int smacker_decode_tree(GetBitContext *gb, HuffContext *hc, uint32_t prefix, int length)
98 {
99  if(!get_bits1(gb)){ //Leaf
100  if(hc->current >= 256){
101  av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");
102  return -1;
103  }
104  if(length){
105  hc->bits[hc->current] = prefix;
106  hc->lengths[hc->current] = length;
107  } else {
108  hc->bits[hc->current] = 0;
109  hc->lengths[hc->current] = 0;
110  }
111  hc->values[hc->current] = get_bits(gb, 8);
112  hc->current++;
113  if(hc->maxlength < length)
114  hc->maxlength = length;
115  return 0;
116  } else { //Node
117  int r;
118  length++;
119  r = smacker_decode_tree(gb, hc, prefix, length);
120  if(r)
121  return r;
122  return smacker_decode_tree(gb, hc, prefix | (1 << (length - 1)), length);
123  }
124 }
125 
130 {
131  if (hc->current + 1 >= hc->length) {
132  av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n");
133  return -1;
134  }
135  if(!get_bits1(gb)){ //Leaf
136  int val, i1, i2, b1, b2;
137  b1 = get_bits_count(gb);
138  i1 = ctx->v1->table ? get_vlc2(gb, ctx->v1->table, SMKTREE_BITS, 3) : 0;
139  b1 = get_bits_count(gb) - b1;
140  b2 = get_bits_count(gb);
141  i2 = ctx->v2->table ? get_vlc2(gb, ctx->v2->table, SMKTREE_BITS, 3) : 0;
142  b2 = get_bits_count(gb) - b2;
143  if (i1 < 0 || i2 < 0)
144  return -1;
145  val = ctx->recode1[i1] | (ctx->recode2[i2] << 8);
146  if(val == ctx->escapes[0]) {
147  ctx->last[0] = hc->current;
148  val = 0;
149  } else if(val == ctx->escapes[1]) {
150  ctx->last[1] = hc->current;
151  val = 0;
152  } else if(val == ctx->escapes[2]) {
153  ctx->last[2] = hc->current;
154  val = 0;
155  }
156 
157  hc->values[hc->current++] = val;
158  return 1;
159  } else { //Node
160  int r = 0, r_new, t;
161 
162  t = hc->current++;
163  r = smacker_decode_bigtree(gb, hc, ctx);
164  if(r < 0)
165  return r;
166  hc->values[t] = SMK_NODE | r;
167  r++;
168  r_new = smacker_decode_bigtree(gb, hc, ctx);
169  if (r_new < 0)
170  return r_new;
171  return r + r_new;
172  }
173 }
174 
178 static int smacker_decode_header_tree(SmackVContext *smk, GetBitContext *gb, int **recodes, int *last, int size)
179 {
180  int res;
181  HuffContext huff;
182  HuffContext tmp1, tmp2;
183  VLC vlc[2];
184  int escapes[3];
185  DBCtx ctx;
186  int err = 0;
187 
188  if(size >= UINT_MAX>>4){ // (((size + 3) >> 2) + 3) << 2 must not overflow
189  av_log(smk->avctx, AV_LOG_ERROR, "size too large\n");
190  return -1;
191  }
192 
193  tmp1.length = 256;
194  tmp1.maxlength = 0;
195  tmp1.current = 0;
196  tmp1.bits = av_mallocz(256 * 4);
197  tmp1.lengths = av_mallocz(256 * sizeof(int));
198  tmp1.values = av_mallocz(256 * sizeof(int));
199 
200  tmp2.length = 256;
201  tmp2.maxlength = 0;
202  tmp2.current = 0;
203  tmp2.bits = av_mallocz(256 * 4);
204  tmp2.lengths = av_mallocz(256 * sizeof(int));
205  tmp2.values = av_mallocz(256 * sizeof(int));
206 
207  memset(&vlc[0], 0, sizeof(VLC));
208  memset(&vlc[1], 0, sizeof(VLC));
209 
210  if(get_bits1(gb)) {
211  smacker_decode_tree(gb, &tmp1, 0, 0);
212  skip_bits1(gb);
213  res = init_vlc(&vlc[0], SMKTREE_BITS, tmp1.length,
214  tmp1.lengths, sizeof(int), sizeof(int),
215  tmp1.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
216  if(res < 0) {
217  av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
218  return -1;
219  }
220  } else {
221  av_log(smk->avctx, AV_LOG_ERROR, "Skipping low bytes tree\n");
222  }
223  if(get_bits1(gb)){
224  smacker_decode_tree(gb, &tmp2, 0, 0);
225  skip_bits1(gb);
226  res = init_vlc(&vlc[1], SMKTREE_BITS, tmp2.length,
227  tmp2.lengths, sizeof(int), sizeof(int),
228  tmp2.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
229  if(res < 0) {
230  av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
231  return -1;
232  }
233  } else {
234  av_log(smk->avctx, AV_LOG_ERROR, "Skipping high bytes tree\n");
235  }
236 
237  escapes[0] = get_bits(gb, 8);
238  escapes[0] |= get_bits(gb, 8) << 8;
239  escapes[1] = get_bits(gb, 8);
240  escapes[1] |= get_bits(gb, 8) << 8;
241  escapes[2] = get_bits(gb, 8);
242  escapes[2] |= get_bits(gb, 8) << 8;
243 
244  last[0] = last[1] = last[2] = -1;
245 
246  ctx.escapes[0] = escapes[0];
247  ctx.escapes[1] = escapes[1];
248  ctx.escapes[2] = escapes[2];
249  ctx.v1 = &vlc[0];
250  ctx.v2 = &vlc[1];
251  ctx.recode1 = tmp1.values;
252  ctx.recode2 = tmp2.values;
253  ctx.last = last;
254 
255  huff.length = ((size + 3) >> 2) + 4;
256  huff.maxlength = 0;
257  huff.current = 0;
258  huff.values = av_mallocz(huff.length * sizeof(int));
259 
260  if (smacker_decode_bigtree(gb, &huff, &ctx) < 0)
261  err = -1;
262  skip_bits1(gb);
263  if(ctx.last[0] == -1) ctx.last[0] = huff.current++;
264  if(ctx.last[1] == -1) ctx.last[1] = huff.current++;
265  if(ctx.last[2] == -1) ctx.last[2] = huff.current++;
266  if (ctx.last[0] >= huff.length ||
267  ctx.last[1] >= huff.length ||
268  ctx.last[2] >= huff.length) {
269  av_log(smk->avctx, AV_LOG_ERROR, "Huffman codes out of range\n");
270  err = AVERROR_INVALIDDATA;
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 
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, b;
348 
349  b = get_bits_count(gb);
350  while(*table & SMK_NODE) {
351  if(get_bits1(gb))
352  table += (*table) & (~SMK_NODE);
353  table++;
354  }
355  v = *table;
356  b = get_bits_count(gb) - b;
357 
358  if(v != recode[last[0]]) {
359  recode[last[2]] = recode[last[1]];
360  recode[last[1]] = recode[last[0]];
361  recode[last[0]] = v;
362  }
363  return v;
364 }
365 
366 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
367 {
368  const uint8_t *buf = avpkt->data;
369  int buf_size = avpkt->size;
370  SmackVContext * const smk = avctx->priv_data;
371  uint8_t *out;
372  uint32_t *pal;
373  GetBitContext gb;
374  int blocks, blk, bw, bh;
375  int i;
376  int stride;
377 
378  if(buf_size <= 769)
379  return 0;
380 
381  smk->pic.reference = 1;
383  if(avctx->reget_buffer(avctx, &smk->pic) < 0){
384  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
385  return -1;
386  }
387 
388  /* make the palette available on the way out */
389  pal = (uint32_t*)smk->pic.data[1];
390  smk->pic.palette_has_changed = buf[0] & 1;
391  smk->pic.key_frame = !!(buf[0] & 2);
392  if(smk->pic.key_frame)
394  else
396 
397  buf++;
398  for(i = 0; i < 256; i++)
399  *pal++ = bytestream_get_be24(&buf);
400  buf_size -= 769;
401 
402  last_reset(smk->mmap_tbl, smk->mmap_last);
403  last_reset(smk->mclr_tbl, smk->mclr_last);
404  last_reset(smk->full_tbl, smk->full_last);
405  last_reset(smk->type_tbl, smk->type_last);
406  init_get_bits(&gb, buf, buf_size * 8);
407 
408  blk = 0;
409  bw = avctx->width >> 2;
410  bh = avctx->height >> 2;
411  blocks = bw * bh;
412  out = smk->pic.data[0];
413  stride = smk->pic.linesize[0];
414  while(blk < blocks) {
415  int type, run, mode;
416  uint16_t pix;
417 
418  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
419  run = block_runs[(type >> 2) & 0x3F];
420  switch(type & 3){
421  case SMK_BLK_MONO:
422  while(run-- && blk < blocks){
423  int clr, map;
424  int hi, lo;
425  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
426  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
427  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
428  hi = clr >> 8;
429  lo = clr & 0xFF;
430  for(i = 0; i < 4; i++) {
431  if(map & 1) out[0] = hi; else out[0] = lo;
432  if(map & 2) out[1] = hi; else out[1] = lo;
433  if(map & 4) out[2] = hi; else out[2] = lo;
434  if(map & 8) out[3] = hi; else out[3] = lo;
435  map >>= 4;
436  out += stride;
437  }
438  blk++;
439  }
440  break;
441  case SMK_BLK_FULL:
442  mode = 0;
443  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
444  if(get_bits1(&gb)) mode = 1;
445  else if(get_bits1(&gb)) mode = 2;
446  }
447  while(run-- && blk < blocks){
448  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
449  switch(mode){
450  case 0:
451  for(i = 0; i < 4; i++) {
452  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
453  AV_WL16(out+2,pix);
454  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
455  AV_WL16(out,pix);
456  out += stride;
457  }
458  break;
459  case 1:
460  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
461  out[0] = out[1] = pix & 0xFF;
462  out[2] = out[3] = pix >> 8;
463  out += stride;
464  out[0] = out[1] = pix & 0xFF;
465  out[2] = out[3] = pix >> 8;
466  out += stride;
467  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
468  out[0] = out[1] = pix & 0xFF;
469  out[2] = out[3] = pix >> 8;
470  out += stride;
471  out[0] = out[1] = pix & 0xFF;
472  out[2] = out[3] = pix >> 8;
473  out += stride;
474  break;
475  case 2:
476  for(i = 0; i < 2; i++) {
477  uint16_t pix1, pix2;
478  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
479  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
480  AV_WL16(out,pix1);
481  AV_WL16(out+2,pix2);
482  out += stride;
483  AV_WL16(out,pix1);
484  AV_WL16(out+2,pix2);
485  out += stride;
486  }
487  break;
488  }
489  blk++;
490  }
491  break;
492  case SMK_BLK_SKIP:
493  while(run-- && blk < blocks)
494  blk++;
495  break;
496  case SMK_BLK_FILL:
497  mode = type >> 8;
498  while(run-- && blk < blocks){
499  uint32_t col;
500  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
501  col = mode * 0x01010101;
502  for(i = 0; i < 4; i++) {
503  *((uint32_t*)out) = col;
504  out += stride;
505  }
506  blk++;
507  }
508  break;
509  }
510 
511  }
512 
513  *data_size = sizeof(AVFrame);
514  *(AVFrame*)data = smk->pic;
515 
516  /* always report that the buffer was completely consumed */
517  return buf_size;
518 }
519 
520 
521 
522 /*
523  *
524  * Init smacker decoder
525  *
526  */
528 {
529  SmackVContext * const c = avctx->priv_data;
530 
531  c->avctx = avctx;
532 
533  avctx->pix_fmt = PIX_FMT_PAL8;
534 
535 
536  /* decode huffman trees from extradata */
537  if(avctx->extradata_size < 16){
538  av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");
539  return -1;
540  }
541 
542  if (decode_header_trees(c))
543  return -1;
544 
545  return 0;
546 }
547 
548 
549 
550 /*
551  *
552  * Uninit smacker decoder
553  *
554  */
556 {
557  SmackVContext * const smk = avctx->priv_data;
558 
559  av_freep(&smk->mmap_tbl);
560  av_freep(&smk->mclr_tbl);
561  av_freep(&smk->full_tbl);
562  av_freep(&smk->type_tbl);
563 
564  if (smk->pic.data[0])
565  avctx->release_buffer(avctx, &smk->pic);
566 
567  return 0;
568 }
569 
570 
571 typedef struct SmackerAudioContext {
574 
576 {
577  SmackerAudioContext *s = avctx->priv_data;
578 
579  if (avctx->channels < 1 || avctx->channels > 2) {
580  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
581  return AVERROR(EINVAL);
582  }
585 
587  avctx->coded_frame = &s->frame;
588 
589  return 0;
590 }
591 
595 static int smka_decode_frame(AVCodecContext *avctx, void *data,
596  int *got_frame_ptr, AVPacket *avpkt)
597 {
598  SmackerAudioContext *s = avctx->priv_data;
599  const uint8_t *buf = avpkt->data;
600  int buf_size = avpkt->size;
601  GetBitContext gb;
602  HuffContext h[4];
603  VLC vlc[4];
604  int16_t *samples;
605  uint8_t *samples8;
606  int val;
607  int i, res, ret;
608  int unp_size;
609  int bits, stereo;
610  int pred[2] = {0, 0};
611 
612  if (buf_size <= 4) {
613  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
614  return AVERROR(EINVAL);
615  }
616 
617  unp_size = AV_RL32(buf);
618 
619  init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
620 
621  if(!get_bits1(&gb)){
622  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
623  *got_frame_ptr = 0;
624  return 1;
625  }
626  stereo = get_bits1(&gb);
627  bits = get_bits1(&gb);
628  if (stereo ^ (avctx->channels != 1)) {
629  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
630  return AVERROR(EINVAL);
631  }
632  if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {
633  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
634  return AVERROR(EINVAL);
635  }
636 
637  /* get output buffer */
638  s->frame.nb_samples = unp_size / (avctx->channels * (bits + 1));
639  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
640  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
641  return ret;
642  }
643  samples = (int16_t *)s->frame.data[0];
644  samples8 = s->frame.data[0];
645 
646  memset(vlc, 0, sizeof(VLC) * 4);
647  memset(h, 0, sizeof(HuffContext) * 4);
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 -1;
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(i & stereo) {
685  if(vlc[2].table)
686  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
687  else
688  res = 0;
689  val = h[2].values[res];
690  if(vlc[3].table)
691  res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);
692  else
693  res = 0;
694  val |= h[3].values[res] << 8;
695  pred[1] += sign_extend(val, 16);
696  *samples++ = av_clip_int16(pred[1]);
697  } else {
698  if(vlc[0].table)
699  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
700  else
701  res = 0;
702  val = h[0].values[res];
703  if(vlc[1].table)
704  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
705  else
706  res = 0;
707  val |= h[1].values[res] << 8;
708  pred[0] += sign_extend(val, 16);
709  *samples++ = av_clip_int16(pred[0]);
710  }
711  }
712  } else { //8-bit data
713  for(i = stereo; i >= 0; i--)
714  pred[i] = get_bits(&gb, 8);
715  for(i = 0; i <= stereo; i++)
716  *samples8++ = pred[i];
717  for(; i < unp_size; i++) {
718  if(i & stereo){
719  if(vlc[1].table)
720  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
721  else
722  res = 0;
723  pred[1] += sign_extend(h[1].values[res], 8);
724  *samples8++ = av_clip_uint8(pred[1]);
725  } else {
726  if(vlc[0].table)
727  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
728  else
729  res = 0;
730  pred[0] += sign_extend(h[0].values[res], 8);
731  *samples8++ = av_clip_uint8(pred[0]);
732  }
733  }
734  }
735 
736  for(i = 0; i < 4; i++) {
737  if(vlc[i].table)
738  ff_free_vlc(&vlc[i]);
739  av_free(h[i].bits);
740  av_free(h[i].lengths);
741  av_free(h[i].values);
742  }
743 
744  *got_frame_ptr = 1;
745  *(AVFrame *)data = s->frame;
746 
747  return buf_size;
748 }
749 
751  .name = "smackvid",
752  .type = AVMEDIA_TYPE_VIDEO,
753  .id = CODEC_ID_SMACKVIDEO,
754  .priv_data_size = sizeof(SmackVContext),
755  .init = decode_init,
756  .close = decode_end,
757  .decode = decode_frame,
758  .capabilities = CODEC_CAP_DR1,
759  .long_name = NULL_IF_CONFIG_SMALL("Smacker video"),
760 };
761 
763  .name = "smackaud",
764  .type = AVMEDIA_TYPE_AUDIO,
765  .id = CODEC_ID_SMACKAUDIO,
766  .priv_data_size = sizeof(SmackerAudioContext),
769  .capabilities = CODEC_CAP_DR1,
770  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
771 };
772