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mvdec.c
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1 /*
2  * Silicon Graphics Movie demuxer
3  * Copyright (c) 2012 Peter Ross
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  * Silicon Graphics Movie demuxer
25  */
26 
28 #include "libavutil/eval.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/rational.h"
31 
32 #include "avformat.h"
33 #include "internal.h"
34 
35 typedef struct MvContext {
38 
39  int eof_count; ///< number of streams that have finished
40  int stream_index; ///< current stream index
41  int frame[2]; ///< frame nb for current stream
42 
43  int acompression; ///< compression level for audio stream
44  int aformat; ///< audio format
45 } MvContext;
46 
47 #define AUDIO_FORMAT_SIGNED 401
48 
49 static int mv_probe(AVProbeData *p)
50 {
51  if (AV_RB32(p->buf) == MKBETAG('M', 'O', 'V', 'I') &&
52  AV_RB16(p->buf + 4) < 3)
53  return AVPROBE_SCORE_MAX;
54  return 0;
55 }
56 
57 static char *var_read_string(AVIOContext *pb, int size)
58 {
59  int n;
60  char *str;
61 
62  if (size < 0 || size == INT_MAX)
63  return NULL;
64 
65  str = av_malloc(size + 1);
66  if (!str)
67  return NULL;
68  n = avio_get_str(pb, size, str, size + 1);
69  if (n < size)
70  avio_skip(pb, size - n);
71  return str;
72 }
73 
74 static int var_read_int(AVIOContext *pb, int size)
75 {
76  int v;
77  char *s = var_read_string(pb, size);
78  if (!s)
79  return 0;
80  v = strtol(s, NULL, 10);
81  av_free(s);
82  return v;
83 }
84 
86 {
87  AVRational v;
88  char *s = var_read_string(pb, size);
89  if (!s)
90  return (AVRational) { 0, 0 };
91  v = av_d2q(av_strtod(s, NULL), INT_MAX);
92  av_free(s);
93  return v;
94 }
95 
96 static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
97 {
98  char *value = var_read_string(avctx->pb, size);
99  if (value)
100  av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
101 }
102 
103 static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
104 {
105  if (channels <= 0) {
106  av_log(avctx, AV_LOG_ERROR, "Channel count %d invalid.\n", channels);
107  return AVERROR_INVALIDDATA;
108  }
109  st->codec->channels = channels;
112  return 0;
113 }
114 
115 /**
116  * Parse global variable
117  * @return < 0 if unknown
118  */
120  const char *name, int size)
121 {
122  MvContext *mv = avctx->priv_data;
123  AVIOContext *pb = avctx->pb;
124  if (!strcmp(name, "__NUM_I_TRACKS")) {
125  mv->nb_video_tracks = var_read_int(pb, size);
126  } else if (!strcmp(name, "__NUM_A_TRACKS")) {
127  mv->nb_audio_tracks = var_read_int(pb, size);
128  } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
129  var_read_metadata(avctx, name, size);
130  } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") ||
131  !strcmp(name, "OPTIMIZED")) {
132  avio_skip(pb, size); // ignore
133  } else
134  return AVERROR_INVALIDDATA;
135 
136  return 0;
137 }
138 
139 /**
140  * Parse audio variable
141  * @return < 0 if unknown
142  */
143 static int parse_audio_var(AVFormatContext *avctx, AVStream *st,
144  const char *name, int size)
145 {
146  MvContext *mv = avctx->priv_data;
147  AVIOContext *pb = avctx->pb;
148  if (!strcmp(name, "__DIR_COUNT")) {
149  st->nb_frames = var_read_int(pb, size);
150  } else if (!strcmp(name, "AUDIO_FORMAT")) {
151  mv->aformat = var_read_int(pb, size);
152  } else if (!strcmp(name, "COMPRESSION")) {
153  mv->acompression = var_read_int(pb, size);
154  } else if (!strcmp(name, "DEFAULT_VOL")) {
155  var_read_metadata(avctx, name, size);
156  } else if (!strcmp(name, "NUM_CHANNELS")) {
157  return set_channels(avctx, st, var_read_int(pb, size));
158  } else if (!strcmp(name, "SAMPLE_RATE")) {
159  st->codec->sample_rate = var_read_int(pb, size);
160  avpriv_set_pts_info(st, 33, 1, st->codec->sample_rate);
161  } else if (!strcmp(name, "SAMPLE_WIDTH")) {
162  st->codec->bits_per_coded_sample = var_read_int(pb, size) * 8;
163  } else
164  return AVERROR_INVALIDDATA;
165 
166  return 0;
167 }
168 
169 /**
170  * Parse video variable
171  * @return < 0 if unknown
172  */
173 static int parse_video_var(AVFormatContext *avctx, AVStream *st,
174  const char *name, int size)
175 {
176  AVIOContext *pb = avctx->pb;
177  if (!strcmp(name, "__DIR_COUNT")) {
178  st->nb_frames = st->duration = var_read_int(pb, size);
179  } else if (!strcmp(name, "COMPRESSION")) {
180  char *str = var_read_string(pb, size);
181  if (!str)
182  return AVERROR_INVALIDDATA;
183  if (!strcmp(str, "1")) {
185  } else if (!strcmp(str, "2")) {
188  } else if (!strcmp(str, "3")) {
190  } else if (!strcmp(str, "10")) {
192  } else if (!strcmp(str, "MVC2")) {
194  } else {
195  avpriv_request_sample(avctx, "Video compression %s", str);
196  }
197  av_free(str);
198  } else if (!strcmp(name, "FPS")) {
199  AVRational fps = var_read_float(pb, size);
200  avpriv_set_pts_info(st, 64, fps.den, fps.num);
201  st->avg_frame_rate = fps;
202  } else if (!strcmp(name, "HEIGHT")) {
203  st->codec->height = var_read_int(pb, size);
204  } else if (!strcmp(name, "PIXEL_ASPECT")) {
205  st->sample_aspect_ratio = var_read_float(pb, size);
208  INT_MAX);
209  } else if (!strcmp(name, "WIDTH")) {
210  st->codec->width = var_read_int(pb, size);
211  } else if (!strcmp(name, "ORIENTATION")) {
212  if (var_read_int(pb, size) == 1101) {
213  st->codec->extradata = av_strdup("BottomUp");
214  st->codec->extradata_size = 9;
215  }
216  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
217  var_read_metadata(avctx, name, size);
218  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
219  avio_skip(pb, size); // ignore
220  } else
221  return AVERROR_INVALIDDATA;
222 
223  return 0;
224 }
225 
226 static int read_table(AVFormatContext *avctx, AVStream *st,
227  int (*parse)(AVFormatContext *avctx, AVStream *st,
228  const char *name, int size))
229 {
230  int count, i;
231  AVIOContext *pb = avctx->pb;
232  avio_skip(pb, 4);
233  count = avio_rb32(pb);
234  avio_skip(pb, 4);
235  for (i = 0; i < count; i++) {
236  char name[17];
237  int size;
238  avio_read(pb, name, 16);
239  name[sizeof(name) - 1] = 0;
240  size = avio_rb32(pb);
241  if (size < 0) {
242  av_log(avctx, AV_LOG_ERROR, "entry size %d is invalid\n", size);
243  return AVERROR_INVALIDDATA;
244  }
245  if (parse(avctx, st, name, size) < 0) {
246  avpriv_request_sample(avctx, "Variable %s", name);
247  avio_skip(pb, size);
248  }
249  }
250  return 0;
251 }
252 
253 static void read_index(AVIOContext *pb, AVStream *st)
254 {
255  uint64_t timestamp = 0;
256  int i;
257  for (i = 0; i < st->nb_frames; i++) {
258  uint32_t pos = avio_rb32(pb);
259  uint32_t size = avio_rb32(pb);
260  avio_skip(pb, 8);
261  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
262  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
263  timestamp += size / (st->codec->channels * 2);
264  } else {
265  timestamp++;
266  }
267  }
268 }
269 
270 static int mv_read_header(AVFormatContext *avctx)
271 {
272  MvContext *mv = avctx->priv_data;
273  AVIOContext *pb = avctx->pb;
274  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
275  int version, i;
276  int ret;
277 
278  avio_skip(pb, 4);
279 
280  version = avio_rb16(pb);
281  if (version == 2) {
282  uint64_t timestamp;
283  int v;
284  avio_skip(pb, 22);
285 
286  /* allocate audio track first to prevent unnecessary seeking
287  * (audio packet always precede video packet for a given frame) */
288  ast = avformat_new_stream(avctx, NULL);
289  if (!ast)
290  return AVERROR(ENOMEM);
291 
292  vst = avformat_new_stream(avctx, NULL);
293  if (!vst)
294  return AVERROR(ENOMEM);
295  avpriv_set_pts_info(vst, 64, 1, 15);
296  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
297  vst->avg_frame_rate = av_inv_q(vst->time_base);
298  vst->nb_frames = avio_rb32(pb);
299  v = avio_rb32(pb);
300  switch (v) {
301  case 1:
302  vst->codec->codec_id = AV_CODEC_ID_MVC1;
303  break;
304  case 2:
305  vst->codec->pix_fmt = AV_PIX_FMT_ARGB;
306  vst->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
307  break;
308  default:
309  avpriv_request_sample(avctx, "Video compression %i", v);
310  break;
311  }
312  vst->codec->codec_tag = 0;
313  vst->codec->width = avio_rb32(pb);
314  vst->codec->height = avio_rb32(pb);
315  avio_skip(pb, 12);
316 
318  ast->nb_frames = vst->nb_frames;
319  ast->codec->sample_rate = avio_rb32(pb);
320  avpriv_set_pts_info(ast, 33, 1, ast->codec->sample_rate);
321  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
322  return AVERROR_INVALIDDATA;
323 
324  v = avio_rb32(pb);
325  if (v == AUDIO_FORMAT_SIGNED) {
327  } else {
328  avpriv_request_sample(avctx, "Audio compression (format %i)", v);
329  }
330 
331  avio_skip(pb, 12);
332  var_read_metadata(avctx, "title", 0x80);
333  var_read_metadata(avctx, "comment", 0x100);
334  avio_skip(pb, 0x80);
335 
336  timestamp = 0;
337  for (i = 0; i < vst->nb_frames; i++) {
338  uint32_t pos = avio_rb32(pb);
339  uint32_t asize = avio_rb32(pb);
340  uint32_t vsize = avio_rb32(pb);
341  avio_skip(pb, 8);
342  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
343  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
344  timestamp += asize / (ast->codec->channels * 2);
345  }
346  } else if (!version && avio_rb16(pb) == 3) {
347  avio_skip(pb, 4);
348 
349  if ((ret = read_table(avctx, NULL, parse_global_var)) < 0)
350  return ret;
351 
352  if (mv->nb_audio_tracks > 1) {
353  avpriv_request_sample(avctx, "Multiple audio streams support");
354  return AVERROR_PATCHWELCOME;
355  } else if (mv->nb_audio_tracks) {
356  ast = avformat_new_stream(avctx, NULL);
357  if (!ast)
358  return AVERROR(ENOMEM);
360  if ((read_table(avctx, ast, parse_audio_var)) < 0)
361  return ret;
362  if (mv->acompression == 100 &&
363  mv->aformat == AUDIO_FORMAT_SIGNED &&
364  ast->codec->bits_per_coded_sample == 16) {
366  } else {
367  avpriv_request_sample(avctx,
368  "Audio compression %i (format %i, sr %i)",
369  mv->acompression, mv->aformat,
372  }
373  if (ast->codec->channels <= 0) {
374  av_log(avctx, AV_LOG_ERROR, "No valid channel count found.\n");
375  return AVERROR_INVALIDDATA;
376  }
377  }
378 
379  if (mv->nb_video_tracks > 1) {
380  avpriv_request_sample(avctx, "Multiple video streams support");
381  return AVERROR_PATCHWELCOME;
382  } else if (mv->nb_video_tracks) {
383  vst = avformat_new_stream(avctx, NULL);
384  if (!vst)
385  return AVERROR(ENOMEM);
386  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
387  if ((ret = read_table(avctx, vst, parse_video_var))<0)
388  return ret;
389  }
390 
391  if (mv->nb_audio_tracks)
392  read_index(pb, ast);
393 
394  if (mv->nb_video_tracks)
395  read_index(pb, vst);
396  } else {
397  avpriv_request_sample(avctx, "Version %i", version);
398  return AVERROR_PATCHWELCOME;
399  }
400 
401  return 0;
402 }
403 
405 {
406  MvContext *mv = avctx->priv_data;
407  AVIOContext *pb = avctx->pb;
408  AVStream *st = avctx->streams[mv->stream_index];
409  const AVIndexEntry *index;
410  int frame = mv->frame[mv->stream_index];
411  int64_t ret;
412  uint64_t pos;
413 
414  if (frame < st->nb_index_entries) {
415  index = &st->index_entries[frame];
416  pos = avio_tell(pb);
417  if (index->pos > pos)
418  avio_skip(pb, index->pos - pos);
419  else if (index->pos < pos) {
420  if (!pb->seekable)
421  return AVERROR(EIO);
422  ret = avio_seek(pb, index->pos, SEEK_SET);
423  if (ret < 0)
424  return ret;
425  }
426  ret = av_get_packet(pb, pkt, index->size);
427  if (ret < 0)
428  return ret;
429 
430  pkt->stream_index = mv->stream_index;
431  pkt->pts = index->timestamp;
432  pkt->flags |= AV_PKT_FLAG_KEY;
433 
434  mv->frame[mv->stream_index]++;
435  mv->eof_count = 0;
436  } else {
437  mv->eof_count++;
438  if (mv->eof_count >= avctx->nb_streams)
439  return AVERROR_EOF;
440 
441  // avoid returning 0 without a packet
442  return AVERROR(EAGAIN);
443  }
444 
445  mv->stream_index++;
446  if (mv->stream_index >= avctx->nb_streams)
447  mv->stream_index = 0;
448 
449  return 0;
450 }
451 
452 static int mv_read_seek(AVFormatContext *avctx, int stream_index,
453  int64_t timestamp, int flags)
454 {
455  MvContext *mv = avctx->priv_data;
456  AVStream *st = avctx->streams[stream_index];
457  int frame, i;
458 
459  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
460  return AVERROR(ENOSYS);
461 
462  if (!avctx->pb->seekable)
463  return AVERROR(EIO);
464 
465  frame = av_index_search_timestamp(st, timestamp, flags);
466  if (frame < 0)
467  return AVERROR_INVALIDDATA;
468 
469  for (i = 0; i < avctx->nb_streams; i++)
470  mv->frame[i] = frame;
471  return 0;
472 }
473 
475  .name = "mv",
476  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
477  .priv_data_size = sizeof(MvContext),
478  .read_probe = mv_probe,
482 };