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smacker.c
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1 /*
2  * Smacker demuxer
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  * Based on http://wiki.multimedia.cx/index.php?title=Smacker
24  */
25 
26 #include "libavutil/bswap.h"
28 #include "libavutil/intreadwrite.h"
29 #include "avformat.h"
30 #include "internal.h"
31 
32 #define SMACKER_PAL 0x01
33 #define SMACKER_FLAG_RING_FRAME 0x01
34 
35 enum SAudFlags {
41 };
42 
43 typedef struct SmackerContext {
44  /* Smacker file header */
45  uint32_t magic;
46  uint32_t width, height;
47  uint32_t frames;
48  int pts_inc;
49  uint32_t flags;
50  uint32_t audio[7];
51  uint32_t treesize;
54  uint32_t rates[7];
55  uint32_t pad;
56  /* frame info */
57  uint32_t *frm_size;
59  /* internal variables */
60  int cur_frame;
61  int is_ver4;
62  int64_t cur_pts;
63  /* current frame for demuxing */
64  uint8_t pal[768];
65  int indexes[7];
68  int buf_sizes[7];
69  int stream_id[7];
70  int curstream;
71  int64_t nextpos;
72  int64_t aud_pts[7];
74 
75 typedef struct SmackerFrame {
76  int64_t pts;
77  int stream;
78 } SmackerFrame;
79 
80 /* palette used in Smacker */
81 static const uint8_t smk_pal[64] = {
82  0x00, 0x04, 0x08, 0x0C, 0x10, 0x14, 0x18, 0x1C,
83  0x20, 0x24, 0x28, 0x2C, 0x30, 0x34, 0x38, 0x3C,
84  0x41, 0x45, 0x49, 0x4D, 0x51, 0x55, 0x59, 0x5D,
85  0x61, 0x65, 0x69, 0x6D, 0x71, 0x75, 0x79, 0x7D,
86  0x82, 0x86, 0x8A, 0x8E, 0x92, 0x96, 0x9A, 0x9E,
87  0xA2, 0xA6, 0xAA, 0xAE, 0xB2, 0xB6, 0xBA, 0xBE,
88  0xC3, 0xC7, 0xCB, 0xCF, 0xD3, 0xD7, 0xDB, 0xDF,
89  0xE3, 0xE7, 0xEB, 0xEF, 0xF3, 0xF7, 0xFB, 0xFF
90 };
91 
92 
93 static int smacker_probe(AVProbeData *p)
94 {
95  if(p->buf[0] == 'S' && p->buf[1] == 'M' && p->buf[2] == 'K'
96  && (p->buf[3] == '2' || p->buf[3] == '4'))
97  return AVPROBE_SCORE_MAX;
98  else
99  return 0;
100 }
101 
103 {
104  AVIOContext *pb = s->pb;
105  SmackerContext *smk = s->priv_data;
106  AVStream *st, *ast[7];
107  int i, ret;
108  int tbase;
109 
110  /* read and check header */
111  smk->magic = avio_rl32(pb);
112  if (smk->magic != MKTAG('S', 'M', 'K', '2') && smk->magic != MKTAG('S', 'M', 'K', '4'))
113  return AVERROR_INVALIDDATA;
114  smk->width = avio_rl32(pb);
115  smk->height = avio_rl32(pb);
116  smk->frames = avio_rl32(pb);
117  smk->pts_inc = (int32_t)avio_rl32(pb);
118  smk->flags = avio_rl32(pb);
119  if(smk->flags & SMACKER_FLAG_RING_FRAME)
120  smk->frames++;
121  for(i = 0; i < 7; i++)
122  smk->audio[i] = avio_rl32(pb);
123  smk->treesize = avio_rl32(pb);
124 
125  if(smk->treesize >= UINT_MAX/4){ // smk->treesize + 16 must not overflow (this check is probably redundant)
126  av_log(s, AV_LOG_ERROR, "treesize too large\n");
127  return AVERROR_INVALIDDATA;
128  }
129 
130 //FIXME remove extradata "rebuilding"
131  smk->mmap_size = avio_rl32(pb);
132  smk->mclr_size = avio_rl32(pb);
133  smk->full_size = avio_rl32(pb);
134  smk->type_size = avio_rl32(pb);
135  for(i = 0; i < 7; i++) {
136  smk->rates[i] = avio_rl24(pb);
137  smk->aflags[i] = avio_r8(pb);
138  }
139  smk->pad = avio_rl32(pb);
140  /* setup data */
141  if(smk->frames > 0xFFFFFF) {
142  av_log(s, AV_LOG_ERROR, "Too many frames: %i\n", smk->frames);
143  return AVERROR_INVALIDDATA;
144  }
145  smk->frm_size = av_malloc(smk->frames * 4);
146  smk->frm_flags = av_malloc(smk->frames);
147 
148  smk->is_ver4 = (smk->magic != MKTAG('S', 'M', 'K', '2'));
149 
150  /* read frame info */
151  for(i = 0; i < smk->frames; i++) {
152  smk->frm_size[i] = avio_rl32(pb);
153  }
154  for(i = 0; i < smk->frames; i++) {
155  smk->frm_flags[i] = avio_r8(pb);
156  }
157 
158  /* init video codec */
159  st = avformat_new_stream(s, NULL);
160  if (!st)
161  return AVERROR(ENOMEM);
162  smk->videoindex = st->index;
163  st->codec->width = smk->width;
164  st->codec->height = smk->height;
168  st->codec->codec_tag = smk->magic;
169  /* Smacker uses 100000 as internal timebase */
170  if(smk->pts_inc < 0)
171  smk->pts_inc = -smk->pts_inc;
172  else
173  smk->pts_inc *= 100;
174  tbase = 100000;
175  av_reduce(&tbase, &smk->pts_inc, tbase, smk->pts_inc, (1UL<<31)-1);
176  avpriv_set_pts_info(st, 33, smk->pts_inc, tbase);
177  st->duration = smk->frames;
178  /* handle possible audio streams */
179  for(i = 0; i < 7; i++) {
180  smk->indexes[i] = -1;
181  if (smk->rates[i]) {
182  ast[i] = avformat_new_stream(s, NULL);
183  smk->indexes[i] = ast[i]->index;
185  if (smk->aflags[i] & SMK_AUD_BINKAUD) {
187  } else if (smk->aflags[i] & SMK_AUD_USEDCT) {
189  } else if (smk->aflags[i] & SMK_AUD_PACKED){
191  ast[i]->codec->codec_tag = MKTAG('S', 'M', 'K', 'A');
192  } else {
193  ast[i]->codec->codec_id = AV_CODEC_ID_PCM_U8;
194  }
195  if (smk->aflags[i] & SMK_AUD_STEREO) {
196  ast[i]->codec->channels = 2;
198  } else {
199  ast[i]->codec->channels = 1;
201  }
202  ast[i]->codec->sample_rate = smk->rates[i];
203  ast[i]->codec->bits_per_coded_sample = (smk->aflags[i] & SMK_AUD_16BITS) ? 16 : 8;
204  if(ast[i]->codec->bits_per_coded_sample == 16 && ast[i]->codec->codec_id == AV_CODEC_ID_PCM_U8)
206  avpriv_set_pts_info(ast[i], 64, 1, ast[i]->codec->sample_rate
207  * ast[i]->codec->channels * ast[i]->codec->bits_per_coded_sample / 8);
208  }
209  }
210 
211 
212  /* load trees to extradata, they will be unpacked by decoder */
214  st->codec->extradata_size = smk->treesize + 16;
215  if(!st->codec->extradata){
216  av_log(s, AV_LOG_ERROR, "Cannot allocate %i bytes of extradata\n", smk->treesize + 16);
217  av_free(smk->frm_size);
218  av_free(smk->frm_flags);
219  return AVERROR(ENOMEM);
220  }
221  ret = avio_read(pb, st->codec->extradata + 16, st->codec->extradata_size - 16);
222  if(ret != st->codec->extradata_size - 16){
223  av_free(smk->frm_size);
224  av_free(smk->frm_flags);
225  return AVERROR(EIO);
226  }
227  ((int32_t*)st->codec->extradata)[0] = av_le2ne32(smk->mmap_size);
228  ((int32_t*)st->codec->extradata)[1] = av_le2ne32(smk->mclr_size);
229  ((int32_t*)st->codec->extradata)[2] = av_le2ne32(smk->full_size);
230  ((int32_t*)st->codec->extradata)[3] = av_le2ne32(smk->type_size);
231 
232  smk->curstream = -1;
233  smk->nextpos = avio_tell(pb);
234 
235  return 0;
236 }
237 
238 
240 {
241  SmackerContext *smk = s->priv_data;
242  int flags;
243  int ret;
244  int i;
245  int frame_size = 0;
246  int palchange = 0;
247 
248  if (url_feof(s->pb) || smk->cur_frame >= smk->frames)
249  return AVERROR_EOF;
250 
251  /* if we demuxed all streams, pass another frame */
252  if(smk->curstream < 0) {
253  avio_seek(s->pb, smk->nextpos, 0);
254  frame_size = smk->frm_size[smk->cur_frame] & (~3);
255  flags = smk->frm_flags[smk->cur_frame];
256  /* handle palette change event */
257  if(flags & SMACKER_PAL){
258  int size, sz, t, off, j, pos;
259  uint8_t *pal = smk->pal;
260  uint8_t oldpal[768];
261 
262  memcpy(oldpal, pal, 768);
263  size = avio_r8(s->pb);
264  size = size * 4 - 1;
265  if(size + 1 > frame_size)
266  return AVERROR_INVALIDDATA;
267  frame_size -= size;
268  frame_size--;
269  sz = 0;
270  pos = avio_tell(s->pb) + size;
271  while(sz < 256){
272  t = avio_r8(s->pb);
273  if(t & 0x80){ /* skip palette entries */
274  sz += (t & 0x7F) + 1;
275  pal += ((t & 0x7F) + 1) * 3;
276  } else if(t & 0x40){ /* copy with offset */
277  off = avio_r8(s->pb);
278  j = (t & 0x3F) + 1;
279  if (off + j - 1 > 0xff) {
280  av_log(s, AV_LOG_ERROR,
281  "Invalid palette update, offset=%d length=%d extends beyond palette size\n",
282  off, j);
283  return AVERROR_INVALIDDATA;
284  }
285  off *= 3;
286  while(j-- && sz < 256) {
287  *pal++ = oldpal[off + 0];
288  *pal++ = oldpal[off + 1];
289  *pal++ = oldpal[off + 2];
290  sz++;
291  off += 3;
292  }
293  } else { /* new entries */
294  *pal++ = smk_pal[t];
295  *pal++ = smk_pal[avio_r8(s->pb) & 0x3F];
296  *pal++ = smk_pal[avio_r8(s->pb) & 0x3F];
297  sz++;
298  }
299  }
300  avio_seek(s->pb, pos, 0);
301  palchange |= 1;
302  }
303  flags >>= 1;
304  smk->curstream = -1;
305  /* if audio chunks are present, put them to stack and retrieve later */
306  for(i = 0; i < 7; i++) {
307  if(flags & 1) {
308  unsigned int size;
309  uint8_t *tmpbuf;
310 
311  size = avio_rl32(s->pb) - 4;
312  if(size + 4L > frame_size)
313  return AVERROR_INVALIDDATA;
314  frame_size -= size;
315  frame_size -= 4;
316  smk->curstream++;
317  tmpbuf = av_realloc(smk->bufs[smk->curstream], size);
318  if (!tmpbuf)
319  return AVERROR(ENOMEM);
320  smk->bufs[smk->curstream] = tmpbuf;
321  smk->buf_sizes[smk->curstream] = size;
322  ret = avio_read(s->pb, smk->bufs[smk->curstream], size);
323  if(ret != size)
324  return AVERROR(EIO);
325  smk->stream_id[smk->curstream] = smk->indexes[i];
326  }
327  flags >>= 1;
328  }
329  if (frame_size < 0)
330  return AVERROR_INVALIDDATA;
331  if (av_new_packet(pkt, frame_size + 769))
332  return AVERROR(ENOMEM);
333  if(smk->frm_size[smk->cur_frame] & 1)
334  palchange |= 2;
335  pkt->data[0] = palchange;
336  memcpy(pkt->data + 1, smk->pal, 768);
337  ret = avio_read(s->pb, pkt->data + 769, frame_size);
338  if(ret != frame_size)
339  return AVERROR(EIO);
340  pkt->stream_index = smk->videoindex;
341  pkt->size = ret + 769;
342  smk->cur_frame++;
343  smk->nextpos = avio_tell(s->pb);
344  } else {
345  if (av_new_packet(pkt, smk->buf_sizes[smk->curstream]))
346  return AVERROR(ENOMEM);
347  memcpy(pkt->data, smk->bufs[smk->curstream], smk->buf_sizes[smk->curstream]);
348  pkt->size = smk->buf_sizes[smk->curstream];
349  pkt->stream_index = smk->stream_id[smk->curstream];
350  pkt->pts = smk->aud_pts[smk->curstream];
351  smk->aud_pts[smk->curstream] += AV_RL32(pkt->data);
352  smk->curstream--;
353  }
354 
355  return 0;
356 }
357 
359 {
360  SmackerContext *smk = s->priv_data;
361  int i;
362 
363  for(i = 0; i < 7; i++)
364  av_free(smk->bufs[i]);
365  av_free(smk->frm_size);
366  av_free(smk->frm_flags);
367 
368  return 0;
369 }
370 
372  .name = "smk",
373  .long_name = NULL_IF_CONFIG_SMALL("Smacker"),
374  .priv_data_size = sizeof(SmackerContext),
379 };