FFmpeg: libavformat/mvdec.c Source File

FFmpeg
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 
27 #include "libavutil/eval.h"
28 #include "libavutil/intreadwrite.h"
29 #include "libavutil/rational.h"
30 #include "avformat.h"
31 #include "internal.h"
32 
33  typedef struct {
34   int nb_video_tracks;
35   int nb_audio_tracks;
36 
37   int eof_count; /**< number of streams that have finished */
38   int stream_index; /**< current stream index */
39   int frame[2]; /**< frame nb for current stream */
40 } MvContext;
41 
42  #define AUDIO_FORMAT_SIGNED 401
43 
44  static int mv_probe(AVProbeData *p)
45 {
46  if (AV_RB32(p->buf) == MKBETAG('M','O','V','I') && AV_RB16(p->buf + 4) < 3)
47  return AVPROBE_SCORE_MAX;
48  return 0;
49 }
50 
51  static char * var_read_string(AVIOContext *pb, int size)
52 {
53  char *str = av_malloc(size + 1);
54  int n;
55  if (!str)
56  return NULL;
57  n = avio_get_str(pb, size, str, size + 1);
58  if (n < size)
59  avio_skip(pb, size - n);
60  return str;
61 }
62 
63  static int var_read_int(AVIOContext *pb, int size)
64 {
65  int v;
66  char * s = var_read_string(pb, size);
67  if (!s || sscanf(s, "%d", &v) != 1)
68  v = 0;
69  av_free(s);
70  return v;
71 }
72 
73  static AVRational var_read_float(AVIOContext *pb, int size)
74 {
75  AVRational v;
76  char * s = var_read_string(pb, size);
77  if (!s)
78  return (AVRational){0, 0};
79  v = av_d2q(av_strtod(s, NULL), INT_MAX);
80  av_free(s);
81  return v;
82 }
83 
84  static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
85 {
86  char *value = var_read_string(avctx->pb, size);
87  if (value)
88  av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
89 }
90 
91  static int set_channels(AVFormatContext *avctx, AVStream *st, int channels) {
92  if (channels <= 0) {
93  av_log(avctx, AV_LOG_ERROR, "Channel count %d invalid\n", channels);
94  return AVERROR_INVALIDDATA;
95  }
96  st->codec->channels = channels;
97  st->codec->channel_layout = (st->codec->channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
98  return 0;
99 }
100 
101 /**
102  * Parse global variable
103  * @return < 0 if unknown
104  */
105  static int parse_global_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
106 {
107  MvContext *mv = avctx->priv_data;
108  AVIOContext *pb = avctx->pb;
109  if (!strcmp(name, "__NUM_I_TRACKS")) {
110  mv->nb_video_tracks = var_read_int(pb, size);
111  } else if (!strcmp(name, "__NUM_A_TRACKS")) {
112  mv->nb_audio_tracks = var_read_int(pb, size);
113  } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
114  var_read_metadata(avctx, name, size);
115  } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") || !strcmp(name, "OPTIMIZED")) {
116  avio_skip(pb, size); // ignore
117  } else
118  return -1;
119 
120  return 0;
121 }
122 
123 /**
124  * Parse audio variable
125  * @return < 0 if unknown
126  */
127  static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
128 {
129  AVIOContext *pb = avctx->pb;
130  if (!strcmp(name, "__DIR_COUNT")) {
131  st->nb_frames = var_read_int(pb, size);
132  } else if (!strcmp(name, "AUDIO_FORMAT")) {
133  st->codec->codec_id = var_read_int(pb, size);
134  } else if (!strcmp(name, "COMPRESSION")) {
135  st->codec->codec_tag = var_read_int(pb, size);
136  } else if (!strcmp(name, "DEFAULT_VOL")) {
137  var_read_metadata(avctx, name, size);
138  } else if (!strcmp(name, "NUM_CHANNELS")) {
139  return set_channels(avctx, st, var_read_int(pb, size));
140  } else if (!strcmp(name, "SAMPLE_RATE")) {
141  st->codec->sample_rate = var_read_int(pb, size);
142  avpriv_set_pts_info(st, 33, 1, st->codec->sample_rate);
143  } else if (!strcmp(name, "SAMPLE_WIDTH")) {
144  st->codec->bits_per_coded_sample = var_read_int(pb, size) * 8;
145  } else
146  return -1;
147  return 0;
148 }
149 
150 /**
151  * Parse video variable
152  * @return < 0 if unknown
153  */
154  static int parse_video_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
155 {
156  AVIOContext *pb = avctx->pb;
157  if (!strcmp(name, "__DIR_COUNT")) {
158  st->nb_frames = st->duration = var_read_int(pb, size);
159  } else if (!strcmp(name, "COMPRESSION")) {
160  char * str = var_read_string(pb, size);
161  if (!str)
162  return AVERROR_INVALIDDATA;
163  if (!strcmp(str, "1")) {
164  st->codec->codec_id = AV_CODEC_ID_MVC1;
165  } else if (!strcmp(str, "2")) {
166  st->codec->pix_fmt = AV_PIX_FMT_ABGR;
167  st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
168  } else if (!strcmp(str, "3")) {
169  st->codec->codec_id = AV_CODEC_ID_SGIRLE;
170  } else if (!strcmp(str, "10")) {
171  st->codec->codec_id = AV_CODEC_ID_MJPEG;
172  } else if (!strcmp(str, "MVC2")) {
173  st->codec->codec_id = AV_CODEC_ID_MVC2;
174  } else {
175  avpriv_request_sample(avctx, "video compression %s", str);
176  }
177  av_free(str);
178  } else if (!strcmp(name, "FPS")) {
179  AVRational fps = var_read_float(pb, size);
180  avpriv_set_pts_info(st, 64, fps.den, fps.num);
181  } else if (!strcmp(name, "HEIGHT")) {
182  st->codec->height = var_read_int(pb, size);
183  } else if (!strcmp(name, "PIXEL_ASPECT")) {
184  st->sample_aspect_ratio = var_read_float(pb, size);
185  av_reduce(&st->sample_aspect_ratio.num, &st->sample_aspect_ratio.den,
186  st->sample_aspect_ratio.num, st->sample_aspect_ratio.den, INT_MAX);
187  } else if (!strcmp(name, "WIDTH")) {
188  st->codec->width = var_read_int(pb, size);
189  } else if (!strcmp(name, "ORIENTATION")) {
190  if (var_read_int(pb, size) == 1101) {
191  st->codec->extradata = av_strdup("BottomUp");
192  st->codec->extradata_size = 9;
193  }
194  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
195  var_read_metadata(avctx, name, size);
196  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
197  avio_skip(pb, size); // ignore
198  } else
199  return -1;
200  return 0;
201 }
202 
203  static void read_table(AVFormatContext *avctx, AVStream *st, int (*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
204 {
205  int count, i;
206  AVIOContext *pb = avctx->pb;
207  avio_skip(pb, 4);
208  count = avio_rb32(pb);
209  avio_skip(pb, 4);
210  for (i = 0; i < count; i++) {
211  char name[17];
212  int size;
213  avio_read(pb, name, 16);
214  name[sizeof(name) - 1] = 0;
215  size = avio_rb32(pb);
216  if (parse(avctx, st, name, size) < 0) {
217  avpriv_request_sample(avctx, "variable %s", name);
218  avio_skip(pb, size);
219  }
220  }
221 }
222 
223  static void read_index(AVIOContext *pb, AVStream *st)
224 {
225  uint64_t timestamp = 0;
226  int i;
227  for (i = 0; i < st->nb_frames; i++) {
228  uint32_t pos = avio_rb32(pb);
229  uint32_t size = avio_rb32(pb);
230  avio_skip(pb, 8);
231  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
232  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
233  timestamp += size / (st->codec->channels * 2);
234  } else {
235  timestamp++;
236  }
237  }
238 }
239 
240  static int mv_read_header(AVFormatContext *avctx)
241 {
242  MvContext *mv = avctx->priv_data;
243  AVIOContext *pb = avctx->pb;
244  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
245  int version, i;
246 
247  avio_skip(pb, 4);
248 
249  version = avio_rb16(pb);
250  if (version == 2) {
251  uint64_t timestamp;
252  int v;
253  avio_skip(pb, 22);
254 
255  /* allocate audio track first to prevent unnecessary seeking
256  (audio packet always precede video packet for a given frame) */
257  ast = avformat_new_stream(avctx, NULL);
258  if (!ast)
259  return AVERROR(ENOMEM);
260 
261  vst = avformat_new_stream(avctx, NULL);
262  if (!vst)
263  return AVERROR(ENOMEM);
264  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
265  avpriv_set_pts_info(vst, 64, 1, 15);
266  vst->nb_frames = avio_rb32(pb);
267  v = avio_rb32(pb);
268  switch (v) {
269  case 1:
270  vst->codec->codec_id = AV_CODEC_ID_MVC1;
271  break;
272  case 2:
273  vst->codec->pix_fmt = AV_PIX_FMT_ARGB;
274  vst->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
275  break;
276  default:
277  avpriv_request_sample(avctx, "video compression %i", v);
278  break;
279  }
280  vst->codec->codec_tag = 0;
281  vst->codec->width = avio_rb32(pb);
282  vst->codec->height = avio_rb32(pb);
283  avio_skip(pb, 12);
284 
285  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
286  ast->nb_frames = vst->nb_frames;
287  ast->codec->sample_rate = avio_rb32(pb);
288  avpriv_set_pts_info(ast, 33, 1, ast->codec->sample_rate);
289  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
290  return AVERROR_INVALIDDATA;
291 
292  v = avio_rb32(pb);
293  if (v == AUDIO_FORMAT_SIGNED) {
294  ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
295  } else {
296  avpriv_request_sample(avctx, "audio compression (format %i)", v);
297  }
298 
299  avio_skip(pb, 12);
300  var_read_metadata(avctx, "title", 0x80);
301  var_read_metadata(avctx, "comment", 0x100);
302  avio_skip(pb, 0x80);
303 
304  timestamp = 0;
305  for (i = 0; i < vst->nb_frames; i++) {
306  uint32_t pos = avio_rb32(pb);
307  uint32_t asize = avio_rb32(pb);
308  uint32_t vsize = avio_rb32(pb);
309  avio_skip(pb, 8);
310  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
311  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
312  timestamp += asize / (ast->codec->channels * 2);
313  }
314  } else if (!version && avio_rb16(pb) == 3) {
315  avio_skip(pb, 4);
316 
317  read_table(avctx, NULL, parse_global_var);
318 
319  if (mv->nb_audio_tracks > 1) {
320  avpriv_request_sample(avctx, "multiple audio streams support");
321  return AVERROR_PATCHWELCOME;
322  } else if (mv->nb_audio_tracks) {
323  ast = avformat_new_stream(avctx, NULL);
324  if (!ast)
325  return AVERROR(ENOMEM);
326  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
327  /* temporarily store compression value in codec_tag; format value in codec_id */
328  read_table(avctx, ast, parse_audio_var);
329  if (ast->codec->codec_tag == 100 && ast->codec->codec_id == AUDIO_FORMAT_SIGNED && ast->codec->bits_per_coded_sample == 16) {
330  ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
331  } else {
332  avpriv_request_sample(avctx, "audio compression %i (format %i, width %i)",
333  ast->codec->codec_tag, ast->codec->codec_id, ast->codec->bits_per_coded_sample);
334  ast->codec->codec_id = AV_CODEC_ID_NONE;
335  }
336  ast->codec->codec_tag = 0;
337  if (ast->codec->channels <= 0) {
338  av_log(avctx, AV_LOG_ERROR, "No valid channel count found\n");
339  return AVERROR_INVALIDDATA;
340  }
341  }
342 
343  if (mv->nb_video_tracks > 1) {
344  avpriv_request_sample(avctx, "multiple video streams support");
345  return AVERROR_PATCHWELCOME;
346  } else if (mv->nb_video_tracks) {
347  vst = avformat_new_stream(avctx, NULL);
348  if (!vst)
349  return AVERROR(ENOMEM);
350  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
351  read_table(avctx, vst, parse_video_var);
352  }
353 
354  if (mv->nb_audio_tracks)
355  read_index(pb, ast);
356 
357  if (mv->nb_video_tracks)
358  read_index(pb, vst);
359  } else {
360  avpriv_request_sample(avctx, "version %i", version);
361  return AVERROR_PATCHWELCOME;
362  }
363 
364  return 0;
365 }
366 
367  static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
368 {
369  MvContext *mv = avctx->priv_data;
370  AVIOContext *pb = avctx->pb;
371  AVStream *st = avctx->streams[mv->stream_index];
372  const AVIndexEntry *index;
373  int frame = mv->frame[mv->stream_index];
374  int ret;
375  uint64_t pos;
376 
377  if (frame < st->nb_index_entries) {
378  index = &st->index_entries[frame];
379  pos = avio_tell(pb);
380  if (index->pos > pos)
381  avio_skip(pb, index->pos - pos);
382  else if (index->pos < pos) {
383  if (!pb->seekable)
384  return AVERROR(EIO);
385  ret = avio_seek(pb, index->pos, SEEK_SET);
386  if (ret < 0)
387  return ret;
388  }
389  ret = av_get_packet(pb, pkt, index->size);
390  if (ret < 0)
391  return ret;
392 
393  pkt->stream_index = mv->stream_index;
394  pkt->pts = index->timestamp;
395  pkt->flags |= AV_PKT_FLAG_KEY;
396 
397  mv->frame[mv->stream_index]++;
398  mv->eof_count = 0;
399  } else {
400  mv->eof_count++;
401  if (mv->eof_count >= avctx->nb_streams)
402  return AVERROR_EOF;
403  }
404 
405  mv->stream_index++;
406  if (mv->stream_index >= avctx->nb_streams)
407  mv->stream_index = 0;
408 
409  return 0;
410 }
411 
412  static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t timestamp, int flags)
413 {
414  MvContext *mv = avctx->priv_data;
415  AVStream *st = avctx->streams[stream_index];
416  int frame, i;
417 
418  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
419  return AVERROR(ENOSYS);
420 
421  if (!avctx->pb->seekable)
422  return AVERROR(EIO);
423 
424  frame = av_index_search_timestamp(st, timestamp, flags);
425  if (frame < 0)
426  return -1;
427 
428  for (i = 0; i < avctx->nb_streams; i++)
429  mv->frame[i] = frame;
430  return 0;
431 }
432 
433  AVInputFormat ff_mv_demuxer = {
434  .name = "mv",
435  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
436  .priv_data_size = sizeof(MvContext),
437  .read_probe = mv_probe,
438  .read_header = mv_read_header,
439  .read_packet = mv_read_packet,
440  .read_seek = mv_read_seek,
441 };
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