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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) + 4;
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  if ((ret = ff_reget_buffer(avctx, &smk->pic)) < 0)
385  return ret;
386 
387  /* make the palette available on the way out */
388  pal = (uint32_t*)smk->pic.data[1];
389  bytestream2_init(&gb2, avpkt->data, avpkt->size);
390  flags = bytestream2_get_byteu(&gb2);
391  smk->pic.palette_has_changed = flags & 1;
392  smk->pic.key_frame = !!(flags & 2);
393  if(smk->pic.key_frame)
394  smk->pic.pict_type = AV_PICTURE_TYPE_I;
395  else
396  smk->pic.pict_type = AV_PICTURE_TYPE_P;
397 
398  for(i = 0; i < 256; i++)
399  *pal++ = 0xFFU << 24 | bytestream2_get_be24u(&gb2);
400 
401  last_reset(smk->mmap_tbl, smk->mmap_last);
402  last_reset(smk->mclr_tbl, smk->mclr_last);
403  last_reset(smk->full_tbl, smk->full_last);
404  last_reset(smk->type_tbl, smk->type_last);
405  init_get_bits(&gb, avpkt->data + 769, (avpkt->size - 769) * 8);
406 
407  blk = 0;
408  bw = avctx->width >> 2;
409  bh = avctx->height >> 2;
410  blocks = bw * bh;
411  out = smk->pic.data[0];
412  stride = smk->pic.linesize[0];
413  while(blk < blocks) {
414  int type, run, mode;
415  uint16_t pix;
416 
417  type = smk_get_code(&gb, smk->type_tbl, smk->type_last);
418  run = block_runs[(type >> 2) & 0x3F];
419  switch(type & 3){
420  case SMK_BLK_MONO:
421  while(run-- && blk < blocks){
422  int clr, map;
423  int hi, lo;
424  clr = smk_get_code(&gb, smk->mclr_tbl, smk->mclr_last);
425  map = smk_get_code(&gb, smk->mmap_tbl, smk->mmap_last);
426  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
427  hi = clr >> 8;
428  lo = clr & 0xFF;
429  for(i = 0; i < 4; i++) {
430  if(map & 1) out[0] = hi; else out[0] = lo;
431  if(map & 2) out[1] = hi; else out[1] = lo;
432  if(map & 4) out[2] = hi; else out[2] = lo;
433  if(map & 8) out[3] = hi; else out[3] = lo;
434  map >>= 4;
435  out += stride;
436  }
437  blk++;
438  }
439  break;
440  case SMK_BLK_FULL:
441  mode = 0;
442  if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes
443  if(get_bits1(&gb)) mode = 1;
444  else if(get_bits1(&gb)) mode = 2;
445  }
446  while(run-- && blk < blocks){
447  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
448  switch(mode){
449  case 0:
450  for(i = 0; i < 4; i++) {
451  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
452  AV_WL16(out+2,pix);
453  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
454  AV_WL16(out,pix);
455  out += stride;
456  }
457  break;
458  case 1:
459  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
460  out[0] = out[1] = pix & 0xFF;
461  out[2] = out[3] = pix >> 8;
462  out += stride;
463  out[0] = out[1] = pix & 0xFF;
464  out[2] = out[3] = pix >> 8;
465  out += stride;
466  pix = smk_get_code(&gb, smk->full_tbl, smk->full_last);
467  out[0] = out[1] = pix & 0xFF;
468  out[2] = out[3] = pix >> 8;
469  out += stride;
470  out[0] = out[1] = pix & 0xFF;
471  out[2] = out[3] = pix >> 8;
472  out += stride;
473  break;
474  case 2:
475  for(i = 0; i < 2; i++) {
476  uint16_t pix1, pix2;
477  pix2 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
478  pix1 = smk_get_code(&gb, smk->full_tbl, smk->full_last);
479  AV_WL16(out,pix1);
480  AV_WL16(out+2,pix2);
481  out += stride;
482  AV_WL16(out,pix1);
483  AV_WL16(out+2,pix2);
484  out += stride;
485  }
486  break;
487  }
488  blk++;
489  }
490  break;
491  case SMK_BLK_SKIP:
492  while(run-- && blk < blocks)
493  blk++;
494  break;
495  case SMK_BLK_FILL:
496  mode = type >> 8;
497  while(run-- && blk < blocks){
498  uint32_t col;
499  out = smk->pic.data[0] + (blk / bw) * (stride * 4) + (blk % bw) * 4;
500  col = mode * 0x01010101;
501  for(i = 0; i < 4; i++) {
502  *((uint32_t*)out) = col;
503  out += stride;
504  }
505  blk++;
506  }
507  break;
508  }
509 
510  }
511 
512  if ((ret = av_frame_ref(data, &smk->pic)) < 0)
513  return ret;
514 
515  *got_frame = 1;
516 
517  /* always report that the buffer was completely consumed */
518  return avpkt->size;
519 }
520 
521 
522 
523 /*
524  *
525  * Init smacker decoder
526  *
527  */
528 static av_cold int decode_init(AVCodecContext *avctx)
529 {
530  SmackVContext * const c = avctx->priv_data;
531 
532  c->avctx = avctx;
533 
534  avctx->pix_fmt = AV_PIX_FMT_PAL8;
535  avcodec_get_frame_defaults(&c->pic);
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 AVERROR(EINVAL);
541  }
542 
543  if (decode_header_trees(c))
544  return AVERROR_INVALIDDATA;
545 
546  return 0;
547 }
548 
549 
550 
551 /*
552  *
553  * Uninit smacker decoder
554  *
555  */
556 static av_cold int decode_end(AVCodecContext *avctx)
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  av_frame_unref(&smk->pic);
566 
567  return 0;
568 }
569 
570 
571 static av_cold int smka_decode_init(AVCodecContext *avctx)
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  }
577  avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
578  avctx->sample_fmt = avctx->bits_per_coded_sample == 8 ? AV_SAMPLE_FMT_U8 : AV_SAMPLE_FMT_S16;
579 
580  return 0;
581 }
582 
583 /**
584  * Decode Smacker audio data
585  */
586 static int smka_decode_frame(AVCodecContext *avctx, void *data,
587  int *got_frame_ptr, AVPacket *avpkt)
588 {
589  AVFrame *frame = data;
590  const uint8_t *buf = avpkt->data;
591  int buf_size = avpkt->size;
592  GetBitContext gb;
593  HuffContext h[4] = { { 0 } };
594  VLC vlc[4] = { { 0 } };
595  int16_t *samples;
596  uint8_t *samples8;
597  int val;
598  int i, res, ret;
599  int unp_size;
600  int bits, stereo;
601  int pred[2] = {0, 0};
602 
603  if (buf_size <= 4) {
604  av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
605  return AVERROR(EINVAL);
606  }
607 
608  unp_size = AV_RL32(buf);
609 
610  if (unp_size > (1U<<24)) {
611  av_log(avctx, AV_LOG_ERROR, "packet is too big\n");
612  return AVERROR_INVALIDDATA;
613  }
614 
615  init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
616 
617  if(!get_bits1(&gb)){
618  av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
619  *got_frame_ptr = 0;
620  return 1;
621  }
622  stereo = get_bits1(&gb);
623  bits = get_bits1(&gb);
624  if (stereo ^ (avctx->channels != 1)) {
625  av_log(avctx, AV_LOG_ERROR, "channels mismatch\n");
626  return AVERROR(EINVAL);
627  }
628  if (bits && avctx->sample_fmt == AV_SAMPLE_FMT_U8) {
629  av_log(avctx, AV_LOG_ERROR, "sample format mismatch\n");
630  return AVERROR(EINVAL);
631  }
632 
633  /* get output buffer */
634  frame->nb_samples = unp_size / (avctx->channels * (bits + 1));
635  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
636  return ret;
637  samples = (int16_t *)frame->data[0];
638  samples8 = frame->data[0];
639 
640  // Initialize
641  for(i = 0; i < (1 << (bits + stereo)); i++) {
642  h[i].length = 256;
643  h[i].maxlength = 0;
644  h[i].current = 0;
645  h[i].bits = av_mallocz(256 * 4);
646  h[i].lengths = av_mallocz(256 * sizeof(int));
647  h[i].values = av_mallocz(256 * sizeof(int));
648  skip_bits1(&gb);
649  if (smacker_decode_tree(&gb, &h[i], 0, 0) < 0) {
650  for (; i >= 0; i--) {
651  if (vlc[i].table)
652  ff_free_vlc(&vlc[i]);
653  av_free(h[i].bits);
654  av_free(h[i].lengths);
655  av_free(h[i].values);
656  }
657  return AVERROR_INVALIDDATA;
658  }
659  skip_bits1(&gb);
660  if(h[i].current > 1) {
661  res = init_vlc(&vlc[i], SMKTREE_BITS, h[i].length,
662  h[i].lengths, sizeof(int), sizeof(int),
663  h[i].bits, sizeof(uint32_t), sizeof(uint32_t), INIT_VLC_LE);
664  if(res < 0) {
665  av_log(avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
666  return AVERROR_INVALIDDATA;
667  }
668  }
669  }
670  /* this codec relies on wraparound instead of clipping audio */
671  if(bits) { //decode 16-bit data
672  for(i = stereo; i >= 0; i--)
673  pred[i] = sign_extend(av_bswap16(get_bits(&gb, 16)), 16);
674  for(i = 0; i <= stereo; i++)
675  *samples++ = pred[i];
676  for(; i < unp_size / 2; i++) {
677  if(get_bits_left(&gb)<0)
678  return AVERROR_INVALIDDATA;
679  if(i & stereo) {
680  if(vlc[2].table)
681  res = get_vlc2(&gb, vlc[2].table, SMKTREE_BITS, 3);
682  else
683  res = 0;
684  if (res < 0) {
685  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
686  return AVERROR_INVALIDDATA;
687  }
688  val = h[2].values[res];
689  if(vlc[3].table)
690  res = get_vlc2(&gb, vlc[3].table, SMKTREE_BITS, 3);
691  else
692  res = 0;
693  if (res < 0) {
694  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
695  return AVERROR_INVALIDDATA;
696  }
697  val |= h[3].values[res] << 8;
698  pred[1] += sign_extend(val, 16);
699  *samples++ = pred[1];
700  } else {
701  if(vlc[0].table)
702  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
703  else
704  res = 0;
705  if (res < 0) {
706  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
707  return AVERROR_INVALIDDATA;
708  }
709  val = h[0].values[res];
710  if(vlc[1].table)
711  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
712  else
713  res = 0;
714  if (res < 0) {
715  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
716  return AVERROR_INVALIDDATA;
717  }
718  val |= h[1].values[res] << 8;
719  pred[0] += sign_extend(val, 16);
720  *samples++ = pred[0];
721  }
722  }
723  } else { //8-bit data
724  for(i = stereo; i >= 0; i--)
725  pred[i] = get_bits(&gb, 8);
726  for(i = 0; i <= stereo; i++)
727  *samples8++ = pred[i];
728  for(; i < unp_size; i++) {
729  if(get_bits_left(&gb)<0)
730  return AVERROR_INVALIDDATA;
731  if(i & stereo){
732  if(vlc[1].table)
733  res = get_vlc2(&gb, vlc[1].table, SMKTREE_BITS, 3);
734  else
735  res = 0;
736  if (res < 0) {
737  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
738  return AVERROR_INVALIDDATA;
739  }
740  pred[1] += sign_extend(h[1].values[res], 8);
741  *samples8++ = pred[1];
742  } else {
743  if(vlc[0].table)
744  res = get_vlc2(&gb, vlc[0].table, SMKTREE_BITS, 3);
745  else
746  res = 0;
747  if (res < 0) {
748  av_log(avctx, AV_LOG_ERROR, "invalid vlc\n");
749  return AVERROR_INVALIDDATA;
750  }
751  pred[0] += sign_extend(h[0].values[res], 8);
752  *samples8++ = pred[0];
753  }
754  }
755  }
756 
757  for(i = 0; i < 4; i++) {
758  if(vlc[i].table)
759  ff_free_vlc(&vlc[i]);
760  av_free(h[i].bits);
761  av_free(h[i].lengths);
762  av_free(h[i].values);
763  }
764 
765  *got_frame_ptr = 1;
766 
767  return buf_size;
768 }
769 
770 AVCodec ff_smacker_decoder = {
771  .name = "smackvid",
772  .type = AVMEDIA_TYPE_VIDEO,
773  .id = AV_CODEC_ID_SMACKVIDEO,
774  .priv_data_size = sizeof(SmackVContext),
775  .init = decode_init,
776  .close = decode_end,
777  .decode = decode_frame,
778  .capabilities = CODEC_CAP_DR1,
779  .long_name = NULL_IF_CONFIG_SMALL("Smacker video"),
780 };
781 
782 AVCodec ff_smackaud_decoder = {
783  .name = "smackaud",
784  .type = AVMEDIA_TYPE_AUDIO,
785  .id = AV_CODEC_ID_SMACKAUDIO,
786  .init = smka_decode_init,
787  .decode = smka_decode_frame,
788  .capabilities = CODEC_CAP_DR1,
789  .long_name = NULL_IF_CONFIG_SMALL("Smacker audio"),
790 };
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