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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 >= hc->length){
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  if (!tmp1.bits || !tmp1.lengths || !tmp1.values ||
208  !tmp2.bits || !tmp2.lengths || !tmp2.values) {
209  err = AVERROR(ENOMEM);
210  goto error;
211  }
212 
213  if(get_bits1(gb)) {
214  res = smacker_decode_tree(gb, &tmp1, 0, 0);
215  if (res < 0) {
216  err = res;
217  goto error;
218  }
219  skip_bits1(gb);
220  if(tmp1.current > 1) {
221  res = init_vlc(&vlc[0], SMKTREE_BITS, tmp1.length,
222  tmp1.lengths, sizeof(int), sizeof(int),
223  tmp1.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
224  if(res < 0) {
225  av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
226  err = res;
227  goto error;
228  }
229  }
230  }
231  if (!vlc[0].table) {
232  av_log(smk->avctx, AV_LOG_ERROR, "Skipping low bytes tree\n");
233  }
234  if(get_bits1(gb)){
235  res = smacker_decode_tree(gb, &tmp2, 0, 0);
236  if (res < 0) {
237  err = res;
238  goto error;
239  }
240  skip_bits1(gb);
241  if(tmp2.current > 1) {
242  res = init_vlc(&vlc[1], SMKTREE_BITS, tmp2.length,
243  tmp2.lengths, sizeof(int), sizeof(int),
244  tmp2.bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
245  if(res < 0) {
246  av_log(smk->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
247  err = res;
248  goto error;
249  }
250  }
251  }
252  if (!vlc[1].table) {
253  av_log(smk->avctx, AV_LOG_ERROR, "Skipping high bytes tree\n");
254  }
255 
256  escapes[0] = get_bits(gb, 16);
257  escapes[1] = get_bits(gb, 16);
258  escapes[2] = get_bits(gb, 16);
259 
260  last[0] = last[1] = last[2] = -1;
261 
262  ctx.escapes[0] = escapes[0];
263  ctx.escapes[1] = escapes[1];
264  ctx.escapes[2] = escapes[2];
265  ctx.v1 = &vlc[0];
266  ctx.v2 = &vlc[1];
267  ctx.recode1 = tmp1.values;
268  ctx.recode2 = tmp2.values;
269  ctx.last = last;
270 
271  huff.length = ((size + 3) >> 2) + 4;
272  huff.maxlength = 0;
273  huff.current = 0;
274  huff.values = av_mallocz(huff.length * sizeof(int));
275  if (!huff.values) {
276  err = AVERROR(ENOMEM);
277  goto error;
278  }
279 
280  if (smacker_decode_bigtree(gb, &huff, &ctx) < 0)
281  err = -1;
282  skip_bits1(gb);
283  if(ctx.last[0] == -1) ctx.last[0] = huff.current++;
284  if(ctx.last[1] == -1) ctx.last[1] = huff.current++;
285  if(ctx.last[2] == -1) ctx.last[2] = huff.current++;
286  if (ctx.last[0] >= huff.length ||
287  ctx.last[1] >= huff.length ||
288  ctx.last[2] >= huff.length) {
289  av_log(smk->avctx, AV_LOG_ERROR, "Huffman codes out of range\n");
290  err = AVERROR_INVALIDDATA;
291  }
292 
293  *recodes = huff.values;
294 
295 error:
296  if(vlc[0].table)
297  ff_free_vlc(&vlc[0]);
298  if(vlc[1].table)
299  ff_free_vlc(&vlc[1]);
300  av_free(tmp1.bits);
301  av_free(tmp1.lengths);
302  av_free(tmp1.values);
303  av_free(tmp2.bits);
304  av_free(tmp2.lengths);
305  av_free(tmp2.values);
306 
307  return err;
308 }
309 
310 static int decode_header_trees(SmackVContext *smk) {
311  GetBitContext gb;
312  int mmap_size, mclr_size, full_size, type_size, ret;
313 
314  mmap_size = AV_RL32(smk->avctx->extradata);
315  mclr_size = AV_RL32(smk->avctx->extradata + 4);
316  full_size = AV_RL32(smk->avctx->extradata + 8);
317  type_size = AV_RL32(smk->avctx->extradata + 12);
318 
319  init_get_bits8(&gb, smk->avctx->extradata + 16, smk->avctx->extradata_size - 16);
320 
321  if(!get_bits1(&gb)) {
322  av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");
323  smk->mmap_tbl = av_malloc(sizeof(int) * 2);
324  if (!smk->mmap_tbl)
325  return AVERROR(ENOMEM);
326  smk->mmap_tbl[0] = 0;
327  smk->mmap_last[0] = smk->mmap_last[1] = smk->mmap_last[2] = 1;
328  } else {
329  ret = smacker_decode_header_tree(smk, &gb, &smk->mmap_tbl, smk->mmap_last, mmap_size);
330  if (ret < 0)
331  return ret;
332  }
333  if(!get_bits1(&gb)) {
334  av_log(smk->avctx, AV_LOG_INFO, "Skipping MCLR tree\n");
335  smk->mclr_tbl = av_malloc(sizeof(int) * 2);
336  if (!smk->mclr_tbl)
337  return AVERROR(ENOMEM);
338  smk->mclr_tbl[0] = 0;
339  smk->mclr_last[0] = smk->mclr_last[1] = smk->mclr_last[2] = 1;
340  } else {
341  ret = smacker_decode_header_tree(smk, &gb, &smk->mclr_tbl, smk->mclr_last, mclr_size);
342  if (ret < 0)
343  return ret;
344  }
345  if(!get_bits1(&gb)) {
346  av_log(smk->avctx, AV_LOG_INFO, "Skipping FULL tree\n");
347  smk->full_tbl = av_malloc(sizeof(int) * 2);
348  if (!smk->full_tbl)
349  return AVERROR(ENOMEM);
350  smk->full_tbl[0] = 0;
351  smk->full_last[0] = smk->full_last[1] = smk->full_last[2] = 1;
352  } else {
353  ret = smacker_decode_header_tree(smk, &gb, &smk->full_tbl, smk->full_last, full_size);
354  if (ret < 0)
355  return ret;
356  }
357  if(!get_bits1(&gb)) {
358  av_log(smk->avctx, AV_LOG_INFO, "Skipping TYPE tree\n");
359  smk->type_tbl = av_malloc(sizeof(int) * 2);
360  if (!smk->type_tbl)
361  return AVERROR(ENOMEM);
362  smk->type_tbl[0] = 0;
363  smk->type_last[0] = smk->type_last[1] = smk->type_last[2] = 1;
364  } else {
365  ret = smacker_decode_header_tree(smk, &gb, &smk->type_tbl, smk->type_last, type_size);
366  if (ret < 0)
367  return ret;
368  }
369 
370  return 0;
371 }
372 
373 static av_always_inline void last_reset(int *recode, int *last) {
374  recode[last[0]] = recode[last[1]] = recode[last[2]] = 0;
375 }
376 
377 /* get code and update history */
378 static av_always_inline int smk_get_code(GetBitContext *gb, int *recode, int *last) {
379  register int *table = recode;
380  int v;
381 
382  while(*table & SMK_NODE) {
383  if(get_bits1(gb))
384  table += (*table) & (~SMK_NODE);
385  table++;
386  }
387  v = *table;
388 
389  if(v != recode[last[0]]) {
390  recode[last[2]] = recode[last[1]];
391  recode[last[1]] = recode[last[0]];
392  recode[last[0]] = v;
393  }
394  return v;
395 }
396 
397 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
398  AVPacket *avpkt)
399 {
400  SmackVContext * const smk = avctx->priv_data;
401  uint8_t *out;
402  uint32_t *pal;
403  GetByteContext gb2;
404  GetBitContext gb;
405  int blocks, blk, bw, bh;
406  int i, ret;
407  int stride;
408  int flags;
409 
410  if (avpkt->size <= 769)
411  return AVERROR_INVALIDDATA;
412 
413  if ((ret = ff_reget_buffer(avctx, smk->pic)) < 0)
414  return ret;
415 
416  /* make the palette available on the way out */
417  pal = (uint32_t*)smk->pic->data[1];
418  bytestream2_init(&gb2, avpkt->data, avpkt->size);
419  flags = bytestream2_get_byteu(&gb2);
420  smk->pic->palette_has_changed = flags & 1;
421  smk->pic->key_frame = !!(flags & 2);
422  if (smk->pic->key_frame)
423  smk->pic->pict_type = AV_PICTURE_TYPE_I;
424  else
425  smk->pic->pict_type = AV_PICTURE_TYPE_P;
426 
427  for(i = 0; i < 256; i++)
428  *pal++ = 0xFFU << 24 | bytestream2_get_be24u(&gb2);
429 
430  last_reset(smk->mmap_tbl, smk->mmap_last);
431  last_reset(smk->mclr_tbl, smk->mclr_last);
432  last_reset(smk->full_tbl, smk->full_last);
433  last_reset(smk->type_tbl, smk->type_last);
434  if ((ret = init_get_bits8(&gb, avpkt->data + 769, avpkt->size - 769)) < 0)
435  return ret;
436 
437  blk = 0;
438  bw = avctx->width >> 2;
439  bh = avctx->height >> 2;
440  blocks = bw * bh;
441  out = smk->pic->data[0];
442  stride = smk->pic->linesize[0];
443  while(blk < blocks) {
444  int type, run, mode;
445  uint16_t pix;
446 
447  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
448  run = block_runs[(type >> 2) & 0x3F];
449  switch(type & 3){
450  case SMK_BLK_MONO:
451  while(run-- && blk < blocks){
452  int clr, map;
453  int hi, lo;
454  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
455  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
456  out = smk->pic->data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
457  hi = clr >> 8;
458  lo = clr & 0xFF;
459  for(i = 0; i < 4; i++) {
460  if(map & 1) out[0] = hi; else out[0] = lo;
461  if(map & 2) out[1] = hi; else out[1] = lo;
462  if(map & 4) out[2] = hi; else out[2] = lo;
463  if(map & 8) out[3] = hi; else out[3] = lo;
464  map >>= 4;
465  out += stride;
466  }
467  blk++;
468  }
469  break;
470  case SMK_BLK_FULL:
471  mode = 0;
472  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
473  if(get_bits1(&gb)) mode = 1;
474  else if(get_bits1(&gb)) mode = 2;
475  }
476  while(run-- && blk < blocks){
477  out = smk->pic->data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
478  switch(mode){
479  case 0:
480  for(i = 0; i < 4; i++) {
481  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
482  AV_WL16(out+2,pix);
483  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
484  AV_WL16(out,pix);
485  out += stride;
486  }
487  break;
488  case 1:
489  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
490  out[0] = out[1] = pix & 0xFF;
491  out[2] = out[3] = pix >> 8;
492  out += stride;
493  out[0] = out[1] = pix & 0xFF;
494  out[2] = out[3] = pix >> 8;
495  out += stride;
496  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
497  out[0] = out[1] = pix & 0xFF;
498  out[2] = out[3] = pix >> 8;
499  out += stride;
500  out[0] = out[1] = pix & 0xFF;
501  out[2] = out[3] = pix >> 8;
502  out += stride;
503  break;
504  case 2:
505  for(i = 0; i < 2; i++) {
506  uint16_t pix1, pix2;
507  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
508  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
509  AV_WL16(out,pix1);
510  AV_WL16(out+2,pix2);
511  out += stride;
512  AV_WL16(out,pix1);
513  AV_WL16(out+2,pix2);
514  out += stride;
515  }
516  break;
517  }
518  blk++;
519  }
520  break;
521  case SMK_BLK_SKIP:
522  while(run-- && blk < blocks)
523  blk++;
524  break;
525  case SMK_BLK_FILL:
526  mode = type >> 8;
527  while(run-- && blk < blocks){
528  uint32_t col;
529  out = smk->pic->data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
530  col = mode * 0x01010101;
531  for(i = 0; i < 4; i++) {
532  *((uint32_t*)out) = col;
533  out += stride;
534  }
535  blk++;
536  }
537  break;
538  }
539 
540  }
541 
542  if ((ret = av_frame_ref(data, smk->pic)) < 0)
543  return ret;
544 
545  *got_frame = 1;
546 
547  /* always report that the buffer was completely consumed */
548  return avpkt->size;
549 }
550 
551 
552 
553 /*
554  *
555  * Uninit smacker decoder
556  *
557  */
558 static av_cold int decode_end(AVCodecContext *avctx)
559 {
560  SmackVContext * const smk = avctx->priv_data;
561 
562  av_freep(&smk->mmap_tbl);
563  av_freep(&smk->mclr_tbl);
564  av_freep(&smk->full_tbl);
565  av_freep(&smk->type_tbl);
566 
567  av_frame_free(&smk->pic);
568 
569  return 0;
570 }
571 
572 
573 /*
574  *
575  * Init smacker decoder
576  *
577  */
578 static av_cold int decode_init(AVCodecContext *avctx)
579 {
580  SmackVContext * const c = avctx->priv_data;
581  int ret;
582 
583  c->avctx = avctx;
584 
585  avctx->pix_fmt = AV_PIX_FMT_PAL8;
586 
587  c->pic = av_frame_alloc();
588  if (!c->pic)
589  return AVERROR(ENOMEM);
590 
591  /* decode huffman trees from extradata */
592  if(avctx->extradata_size < 16){
593  av_log(avctx, AV_LOG_ERROR, "Extradata missing!\n");
594  return AVERROR(EINVAL);
595  }
596 
597  ret = decode_header_trees(c);
598  if (ret < 0) {
599  decode_end(avctx);
600  return ret;
601  }
602 
603  return 0;
604 }
605 
606 
607 static av_cold int smka_decode_init(AVCodecContext *avctx)
608 {
609  if (avctx->channels < 1 || avctx->channels > 2) {
610  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
611  return AVERROR(EINVAL);
612  }
613  avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
614  avctx->sample_fmt = avctx->bits_per_coded_sample == 8 ? AV_SAMPLE_FMT_U8 : AV_SAMPLE_FMT_S16;
615 
616  return 0;
617 }
618 
619 /**
620  * Decode Smacker audio data
621  */
622 static int smka_decode_frame(AVCodecContext *avctx, void *data,
623  int *got_frame_ptr, AVPacket *avpkt)
624 {
625  AVFrame *frame = data;
626  const uint8_t *buf = avpkt->data;
627  int buf_size = avpkt->size;
628  GetBitContext gb;
629  HuffContext h[4] = { { 0 } };
630  VLC vlc[4] = { { 0 } };
631  int16_t *samples;
632  uint8_t *samples8;
633  int val;
634  int i, res, ret;
635  int unp_size;
636  int bits, stereo;
637  int pred[2] = {0, 0};
638 
639  if (buf_size <= 4) {
640  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
641  return AVERROR(EINVAL);
642  }
643 
644  unp_size = AV_RL32(buf);
645 
646  if (unp_size > (1U<<24)) {
647  av_log(avctx, AV_LOG_ERROR, "packet is too big\n");
648  return AVERROR_INVALIDDATA;
649  }
650 
651  if ((ret = init_get_bits8(&gb, buf + 4, buf_size - 4)) < 0)
652  return ret;
653 
654  if(!get_bits1(&gb)){
655  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
656  *got_frame_ptr = 0;
657  return 1;
658  }
659  stereo = get_bits1(&gb);
660  bits = get_bits1(&gb);
661  if (stereo ^ (avctx->channels != 1)) {
662  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
663  return AVERROR(EINVAL);
664  }
665  if (bits == (avctx->sample_fmt == AV_SAMPLE_FMT_U8)) {
666  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
667  return AVERROR(EINVAL);
668  }
669 
670  /* get output buffer */
671  frame->nb_samples = unp_size / (avctx->channels * (bits + 1));
672  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
673  return ret;
674  samples = (int16_t *)frame->data[0];
675  samples8 = frame->data[0];
676 
677  // Initialize
678  for(i = 0; i < (1 << (bits + stereo)); i++) {
679  h[i].length = 256;
680  h[i].maxlength = 0;
681  h[i].current = 0;
682  h[i].bits = av_mallocz(256 * 4);
683  h[i].lengths = av_mallocz(256 * sizeof(int));
684  h[i].values = av_mallocz(256 * sizeof(int));
685  if (!h[i].bits || !h[i].lengths || !h[i].values) {
686  ret = AVERROR(ENOMEM);
687  goto error;
688  }
689  skip_bits1(&gb);
690  if (smacker_decode_tree(&gb, &h[i], 0, 0) < 0) {
691  ret = AVERROR_INVALIDDATA;
692  goto error;
693  }
694  skip_bits1(&gb);
695  if(h[i].current > 1) {
696  res = init_vlc(&vlc[i], SMKTREE_BITS, h[i].length,
697  h[i].lengths, sizeof(int), sizeof(int),
698  h[i].bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
699  if(res < 0) {
700  av_log(avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
701  ret = AVERROR_INVALIDDATA;
702  goto error;
703  }
704  }
705  }
706  /* this codec relies on wraparound instead of clipping audio */
707  if(bits) { //decode 16-bit data
708  for(i = stereo; i >= 0; i--)
709  pred[i] = sign_extend(av_bswap16(get_bits(&gb, 16)), 16);
710  for(i = 0; i <= stereo; i++)
711  *samples++ = pred[i];
712  for(; i < unp_size / 2; i++) {
713  if(get_bits_left(&gb)<0)
714  return AVERROR_INVALIDDATA;
715  if(i & stereo) {
716  if(vlc[2].table)
717  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
718  else
719  res = 0;
720  if (res < 0) {
721  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
722  return AVERROR_INVALIDDATA;
723  }
724  val = h[2].values[res];
725  if(vlc[3].table)
726  res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);
727  else
728  res = 0;
729  if (res < 0) {
730  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
731  return AVERROR_INVALIDDATA;
732  }
733  val |= h[3].values[res] << 8;
734  pred[1] += sign_extend(val, 16);
735  *samples++ = pred[1];
736  } else {
737  if(vlc[0].table)
738  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
739  else
740  res = 0;
741  if (res < 0) {
742  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
743  return AVERROR_INVALIDDATA;
744  }
745  val = h[0].values[res];
746  if(vlc[1].table)
747  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
748  else
749  res = 0;
750  if (res < 0) {
751  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
752  return AVERROR_INVALIDDATA;
753  }
754  val |= h[1].values[res] << 8;
755  pred[0] += sign_extend(val, 16);
756  *samples++ = pred[0];
757  }
758  }
759  } else { //8-bit data
760  for(i = stereo; i >= 0; i--)
761  pred[i] = get_bits(&gb, 8);
762  for(i = 0; i <= stereo; i++)
763  *samples8++ = pred[i];
764  for(; i < unp_size; i++) {
765  if(get_bits_left(&gb)<0)
766  return AVERROR_INVALIDDATA;
767  if(i & stereo){
768  if(vlc[1].table)
769  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
770  else
771  res = 0;
772  if (res < 0) {
773  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
774  return AVERROR_INVALIDDATA;
775  }
776  pred[1] += sign_extend(h[1].values[res], 8);
777  *samples8++ = pred[1];
778  } else {
779  if(vlc[0].table)
780  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
781  else
782  res = 0;
783  if (res < 0) {
784  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
785  return AVERROR_INVALIDDATA;
786  }
787  pred[0] += sign_extend(h[0].values[res], 8);
788  *samples8++ = pred[0];
789  }
790  }
791  }
792 
793  *got_frame_ptr = 1;
794  ret = buf_size;
795 
796 error:
797  for(i = 0; i < 4; i++) {
798  if(vlc[i].table)
799  ff_free_vlc(&vlc[i]);
800  av_free(h[i].bits);
801  av_free(h[i].lengths);
802  av_free(h[i].values);
803  }
804 
805  return ret;
806 }
807 
808 AVCodec ff_smacker_decoder = {
809  .name = "smackvid",
810  .long_name = NULL_IF_CONFIG_SMALL("Smacker video"),
811  .type = AVMEDIA_TYPE_VIDEO,
812  .id = AV_CODEC_ID_SMACKVIDEO,
813  .priv_data_size = sizeof(SmackVContext),
814  .init = decode_init,
815  .close = decode_end,
816  .decode = decode_frame,
817  .capabilities = CODEC_CAP_DR1,
818 };
819 
820 AVCodec ff_smackaud_decoder = {
821  .name = "smackaud",
822  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
823  .type = AVMEDIA_TYPE_AUDIO,
824  .id = AV_CODEC_ID_SMACKAUDIO,
825  .init = smka_decode_init,
826  .decode = smka_decode_frame,
827  .capabilities = CODEC_CAP_DR1,
828 };
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