smacker.c
Go to the documentation of this file.
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 
267  *recodes = huff.values;
268 
269  if(vlc[0].table)
270  ff_free_vlc(&vlc[0]);
271  if(vlc[1].table)
272  ff_free_vlc(&vlc[1]);
273  av_free(tmp1.bits);
274  av_free(tmp1.lengths);
275  av_free(tmp1.values);
276  av_free(tmp2.bits);
277  av_free(tmp2.lengths);
278  av_free(tmp2.values);
279 
280  return err;
281 }
282 
284  GetBitContext gb;
285  int mmap_size, mclr_size, full_size, type_size;
286 
287  mmap_size = AV_RL32(smk->avctx->extradata);
288  mclr_size = AV_RL32(smk->avctx->extradata + 4);
289  full_size = AV_RL32(smk->avctx->extradata + 8);
290  type_size = AV_RL32(smk->avctx->extradata + 12);
291 
292  init_get_bits(&gb, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);
293 
294  if(!get_bits1(&gb)) {
295  av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");
296  smk->mmap_tbl = av_malloc(sizeof(int) * 2);
297  smk->mmap_tbl[0] = 0;
298  smk->mmap_last[0] = smk->mmap_last[1] = smk->mmap_last[2] = 1;
299  } else {
300  if (smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size))
301  return -1;
302  }
303  if(!get_bits1(&gb)) {
304  av_log(smk->avctx, AV_LOG_INFO, "Skipping MCLR tree\n");
305  smk->mclr_tbl = av_malloc(sizeof(int) * 2);
306  smk->mclr_tbl[0] = 0;
307  smk->mclr_last[0] = smk->mclr_last[1] = smk->mclr_last[2] = 1;
308  } else {
309  if (smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size))
310  return -1;
311  }
312  if(!get_bits1(&gb)) {
313  av_log(smk->avctx, AV_LOG_INFO, "Skipping FULL tree\n");
314  smk->full_tbl = av_malloc(sizeof(int) * 2);
315  smk->full_tbl[0] = 0;
316  smk->full_last[0] = smk->full_last[1] = smk->full_last[2] = 1;
317  } else {
318  if (smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size))
319  return -1;
320  }
321  if(!get_bits1(&gb)) {
322  av_log(smk->avctx, AV_LOG_INFO, "Skipping TYPE tree\n");
323  smk->type_tbl = av_malloc(sizeof(int) * 2);
324  smk->type_tbl[0] = 0;
325  smk->type_last[0] = smk->type_last[1] = smk->type_last[2] = 1;
326  } else {
327  if (smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size))
328  return -1;
329  }
330 
331  return 0;
332 }
333 
334 static av_always_inline void last_reset(int *recode, int *last) {
335  recode[last[0]] = recode[last[1]] = recode[last[2]] = 0;
336 }
337 
338 /* get code and update history */
339 static av_always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {
340  register int *table = recode;
341  int v, b;
342 
343  b = get_bits_count(gb);
344  while(*table & SMK_NODE) {
345  if(get_bits1(gb))
346  table += (*table) & (~SMK_NODE);
347  table++;
348  }
349  v = *table;
350  b = get_bits_count(gb) - b;
351 
352  if(v != recode[last[0]]) {
353  recode[last[2]] = recode[last[1]];
354  recode[last[1]] = recode[last[0]];
355  recode[last[0]] = v;
356  }
357  return v;
358 }
359 
360 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
361 {
362  const uint8_t *buf = avpkt->data;
363  int buf_size = avpkt->size;
364  SmackVContext * const smk = avctx->priv_data;
365  uint8_t *out;
366  uint32_t *pal;
367  GetBitContext gb;
368  int blocks, blk, bw, bh;
369  int i;
370  int stride;
371 
372  if(buf_size <= 769)
373  return 0;
374 
375  smk->pic.reference = 1;
377  if(avctx->reget_buffer(avctx, &smk->pic) < 0){
378  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
379  return -1;
380  }
381 
382  /* make the palette available on the way out */
383  pal = (uint32_t*)smk->pic.data[1];
384  smk->pic.palette_has_changed = buf[0] & 1;
385  smk->pic.key_frame = !!(buf[0] & 2);
386  if(smk->pic.key_frame)
388  else
390 
391  buf++;
392  for(i = 0; i < 256; i++)
393  *pal++ = bytestream_get_be24(&buf);
394  buf_size -= 769;
395 
396  last_reset(smk->mmap_tbl, smk->mmap_last);
397  last_reset(smk->mclr_tbl, smk->mclr_last);
398  last_reset(smk->full_tbl, smk->full_last);
399  last_reset(smk->type_tbl, smk->type_last);
400  init_get_bits(&gb, buf, buf_size * 8);
401 
402  blk = 0;
403  bw = avctx->width >> 2;
404  bh = avctx->height >> 2;
405  blocks = bw * bh;
406  out = smk->pic.data[0];
407  stride = smk->pic.linesize[0];
408  while(blk < blocks) {
409  int type, run, mode;
410  uint16_t pix;
411 
412  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
413  run = block_runs[(type >> 2) & 0x3F];
414  switch(type & 3){
415  case SMK_BLK_MONO:
416  while(run-- && blk < blocks){
417  int clr, map;
418  int hi, lo;
419  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
420  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
421  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
422  hi = clr >> 8;
423  lo = clr & 0xFF;
424  for(i = 0; i < 4; i++) {
425  if(map & 1) out[0] = hi; else out[0] = lo;
426  if(map & 2) out[1] = hi; else out[1] = lo;
427  if(map & 4) out[2] = hi; else out[2] = lo;
428  if(map & 8) out[3] = hi; else out[3] = lo;
429  map >>= 4;
430  out += stride;
431  }
432  blk++;
433  }
434  break;
435  case SMK_BLK_FULL:
436  mode = 0;
437  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
438  if(get_bits1(&gb)) mode = 1;
439  else if(get_bits1(&gb)) mode = 2;
440  }
441  while(run-- && blk < blocks){
442  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
443  switch(mode){
444  case 0:
445  for(i = 0; i < 4; i++) {
446  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
447  AV_WL16(out+2,pix);
448  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
449  AV_WL16(out,pix);
450  out += stride;
451  }
452  break;
453  case 1:
454  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
455  out[0] = out[1] = pix & 0xFF;
456  out[2] = out[3] = pix >> 8;
457  out += stride;
458  out[0] = out[1] = pix & 0xFF;
459  out[2] = out[3] = pix >> 8;
460  out += stride;
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  break;
469  case 2:
470  for(i = 0; i < 2; i++) {
471  uint16_t pix1, pix2;
472  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
473  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
474  AV_WL16(out,pix1);
475  AV_WL16(out+2,pix2);
476  out += stride;
477  AV_WL16(out,pix1);
478  AV_WL16(out+2,pix2);
479  out += stride;
480  }
481  break;
482  }
483  blk++;
484  }
485  break;
486  case SMK_BLK_SKIP:
487  while(run-- && blk < blocks)
488  blk++;
489  break;
490  case SMK_BLK_FILL:
491  mode = type >> 8;
492  while(run-- && blk < blocks){
493  uint32_t col;
494  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
495  col = mode * 0x01010101;
496  for(i = 0; i < 4; i++) {
497  *((uint32_t*)out) = col;
498  out += stride;
499  }
500  blk++;
501  }
502  break;
503  }
504 
505  }
506 
507  *data_size = sizeof(AVFrame);
508  *(AVFrame*)data = smk->pic;
509 
510  /* always report that the buffer was completely consumed */
511  return buf_size;
512 }
513 
514 
515 
516 /*
517  *
518  * Init smacker decoder
519  *
520  */
522 {
523  SmackVContext * const c = avctx->priv_data;
524 
525  c->avctx = avctx;
526 
527  avctx->pix_fmt = PIX_FMT_PAL8;
528 
529 
530  /* decode huffman trees from extradata */
531  if(avctx->extradata_size < 16){
532  av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");
533  return -1;
534  }
535 
536  if (decode_header_trees(c))
537  return -1;
538 
539  return 0;
540 }
541 
542 
543 
544 /*
545  *
546  * Uninit smacker decoder
547  *
548  */
550 {
551  SmackVContext * const smk = avctx->priv_data;
552 
553  av_freep(&smk->mmap_tbl);
554  av_freep(&smk->mclr_tbl);
555  av_freep(&smk->full_tbl);
556  av_freep(&smk->type_tbl);
557 
558  if (smk->pic.data[0])
559  avctx->release_buffer(avctx, &smk->pic);
560 
561  return 0;
562 }
563 
564 
565 typedef struct SmackerAudioContext {
568 
570 {
571  SmackerAudioContext *s = avctx->priv_data;
572 
573  if (avctx->channels < 1 || avctx->channels > 2) {
574  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
575  return AVERROR(EINVAL);
576  }
579 
581  avctx->coded_frame = &s->frame;
582 
583  return 0;
584 }
585 
589 static int smka_decode_frame(AVCodecContext *avctx, void *data,
590  int *got_frame_ptr, AVPacket *avpkt)
591 {
592  SmackerAudioContext *s = avctx->priv_data;
593  const uint8_t *buf = avpkt->data;
594  int buf_size = avpkt->size;
595  GetBitContext gb;
596  HuffContext h[4];
597  VLC vlc[4];
598  int16_t *samples;
599  uint8_t *samples8;
600  int val;
601  int i, res, ret;
602  int unp_size;
603  int bits, stereo;
604  int pred[2] = {0, 0};
605 
606  if (buf_size <= 4) {
607  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
608  return AVERROR(EINVAL);
609  }
610 
611  unp_size = AV_RL32(buf);
612 
613  init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
614 
615  if(!get_bits1(&gb)){
616  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
617  *got_frame_ptr = 0;
618  return 1;
619  }
620  stereo = get_bits1(&gb);
621  bits = get_bits1(&gb);
622  if (stereo ^ (avctx->channels != 1)) {
623  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
624  return AVERROR(EINVAL);
625  }
626  if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {
627  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
628  return AVERROR(EINVAL);
629  }
630 
631  /* get output buffer */
632  s->frame.nb_samples = unp_size / (avctx->channels * (bits + 1));
633  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
634  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
635  return ret;
636  }
637  samples = (int16_t *)s->frame.data[0];
638  samples8 = s->frame.data[0];
639 
640  memset(vlc, 0, sizeof(VLC) * 4);
641  memset(h, 0, sizeof(HuffContext) * 4);
642  // Initialize
643  for(i = 0; i < (1 << (bits + stereo)); i++) {
644  h[i].length = 256;
645  h[i].maxlength = 0;
646  h[i].current = 0;
647  h[i].bits = av_mallocz(256 * 4);
648  h[i].lengths = av_mallocz(256 * sizeof(int));
649  h[i].values = av_mallocz(256 * sizeof(int));
650  skip_bits1(&gb);
651  if (smacker_decode_tree(&gb, &h[i], 0, 0) < 0) {
652  for (; i >= 0; i--) {
653  if (vlc[i].table)
654  ff_free_vlc(&vlc[i]);
655  av_free(h[i].bits);
656  av_free(h[i].lengths);
657  av_free(h[i].values);
658  }
659  return AVERROR_INVALIDDATA;
660  }
661  skip_bits1(&gb);
662  if(h[i].current > 1) {
663  res = init_vlc(&vlc[i], SMKTREE_BITS, h[i].length,
664  h[i].lengths, sizeof(int), sizeof(int),
665  h[i].bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
666  if(res < 0) {
667  av_log(avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
668  return -1;
669  }
670  }
671  }
672  if(bits) { //decode 16-bit data
673  for(i = stereo; i >= 0; i--)
674  pred[i] = sign_extend(av_bswap16(get_bits(&gb, 16)), 16);
675  for(i = 0; i <= stereo; i++)
676  *samples++ = pred[i];
677  for(; i < unp_size / 2; i++) {
678  if(i & stereo) {
679  if(vlc[2].table)
680  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
681  else
682  res = 0;
683  val = h[2].values[res];
684  if(vlc[3].table)
685  res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);
686  else
687  res = 0;
688  val |= h[3].values[res] << 8;
689  pred[1] += sign_extend(val, 16);
690  *samples++ = av_clip_int16(pred[1]);
691  } else {
692  if(vlc[0].table)
693  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
694  else
695  res = 0;
696  val = h[0].values[res];
697  if(vlc[1].table)
698  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
699  else
700  res = 0;
701  val |= h[1].values[res] << 8;
702  pred[0] += sign_extend(val, 16);
703  *samples++ = av_clip_int16(pred[0]);
704  }
705  }
706  } else { //8-bit data
707  for(i = stereo; i >= 0; i--)
708  pred[i] = get_bits(&gb, 8);
709  for(i = 0; i <= stereo; i++)
710  *samples8++ = pred[i];
711  for(; i < unp_size; i++) {
712  if(i & stereo){
713  if(vlc[1].table)
714  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
715  else
716  res = 0;
717  pred[1] += sign_extend(h[1].values[res], 8);
718  *samples8++ = av_clip_uint8(pred[1]);
719  } else {
720  if(vlc[0].table)
721  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
722  else
723  res = 0;
724  pred[0] += sign_extend(h[0].values[res], 8);
725  *samples8++ = av_clip_uint8(pred[0]);
726  }
727  }
728  }
729 
730  for(i = 0; i < 4; i++) {
731  if(vlc[i].table)
732  ff_free_vlc(&vlc[i]);
733  av_free(h[i].bits);
734  av_free(h[i].lengths);
735  av_free(h[i].values);
736  }
737 
738  *got_frame_ptr = 1;
739  *(AVFrame *)data = s->frame;
740 
741  return buf_size;
742 }
743 
745  .name = "smackvid",
746  .type = AVMEDIA_TYPE_VIDEO,
747  .id = CODEC_ID_SMACKVIDEO,
748  .priv_data_size = sizeof(SmackVContext),
749  .init = decode_init,
750  .close = decode_end,
751  .decode = decode_frame,
752  .capabilities = CODEC_CAP_DR1,
753  .long_name = NULL_IF_CONFIG_SMALL("Smacker video"),
754 };
755 
757  .name = "smackaud",
758  .type = AVMEDIA_TYPE_AUDIO,
759  .id = CODEC_ID_SMACKAUDIO,
760  .priv_data_size = sizeof(SmackerAudioContext),
763  .capabilities = CODEC_CAP_DR1,
764  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
765 };
766