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sidxindex.c
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1 /*
2  * Copyright (c) 2014 Martin Storsjo
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdio.h>
22 #include <string.h>
23 
24 #include "libavformat/avformat.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/mathematics.h"
28 
29 static int usage(const char *argv0, int ret)
30 {
31  fprintf(stderr, "%s -out foo.mpd file1\n", argv0);
32  return ret;
33 }
34 
35 struct Track {
36  const char *name;
37  int64_t duration;
38  int bitrate;
39  int track_id;
40  int is_audio, is_video;
41  int width, height;
42  int sample_rate, channels;
43  int timescale;
44  char codec_str[30];
48 };
49 
50 struct Tracks {
51  int nb_tracks;
52  int64_t duration;
53  struct Track **tracks;
55 };
56 
57 static void set_codec_str(AVCodecContext *codec, char *str, int size)
58 {
59  switch (codec->codec_id) {
60  case AV_CODEC_ID_H264:
61  snprintf(str, size, "avc1");
62  if (codec->extradata_size >= 4 && codec->extradata[0] == 1) {
63  av_strlcatf(str, size, ".%02x%02x%02x",
64  codec->extradata[1], codec->extradata[2], codec->extradata[3]);
65  }
66  break;
67  case AV_CODEC_ID_AAC:
68  snprintf(str, size, "mp4a.40"); // 0x40 is the mp4 object type for AAC
69  if (codec->extradata_size >= 2) {
70  int aot = codec->extradata[0] >> 3;
71  if (aot == 31)
72  aot = ((AV_RB16(codec->extradata) >> 5) & 0x3f) + 32;
73  av_strlcatf(str, size, ".%d", aot);
74  }
75  break;
76  }
77 }
78 
79 static int find_sidx(struct Tracks *tracks, int start_index,
80  const char *file)
81 {
82  int err = 0;
83  AVIOContext *f = NULL;
84  int i;
85 
86  if ((err = avio_open2(&f, file, AVIO_FLAG_READ, NULL, NULL)) < 0)
87  goto fail;
88 
89  while (!f->eof_reached) {
90  int64_t pos = avio_tell(f);
91  int32_t size, tag;
92 
93  size = avio_rb32(f);
94  tag = avio_rb32(f);
95  if (size < 8)
96  break;
97  if (tag == MKBETAG('s', 'i', 'd', 'x')) {
98  int version, track_id;
99  uint32_t timescale;
100  int64_t earliest_presentation;
101  version = avio_r8(f);
102  avio_rb24(f); /* flags */
103  track_id = avio_rb32(f);
104  timescale = avio_rb32(f);
105  earliest_presentation = version ? avio_rb64(f) : avio_rb32(f);
106  for (i = start_index; i < tracks->nb_tracks; i++) {
107  struct Track *track = tracks->tracks[i];
108  if (!track->sidx_start) {
109  track->sidx_start = pos;
110  track->sidx_length = size;
111  } else if (pos == track->sidx_start + track->sidx_length) {
112  track->sidx_length = pos + size - track->sidx_start;
113  }
114  if (track->track_id == track_id) {
117  }
118  }
119  }
120  if (avio_seek(f, pos + size, SEEK_SET) != pos + size)
121  break;
122  }
123 
124 fail:
125  if (f)
126  avio_close(f);
127  return err;
128 }
129 
130 static int handle_file(struct Tracks *tracks, const char *file)
131 {
132  AVFormatContext *ctx = NULL;
133  int err = 0, i, orig_tracks = tracks->nb_tracks;
134  char errbuf[50], *ptr;
135  struct Track *track;
136 
137  err = avformat_open_input(&ctx, file, NULL, NULL);
138  if (err < 0) {
139  av_strerror(err, errbuf, sizeof(errbuf));
140  fprintf(stderr, "Unable to open %s: %s\n", file, errbuf);
141  return 1;
142  }
143 
144  err = avformat_find_stream_info(ctx, NULL);
145  if (err < 0) {
146  av_strerror(err, errbuf, sizeof(errbuf));
147  fprintf(stderr, "Unable to identify %s: %s\n", file, errbuf);
148  goto fail;
149  }
150 
151  if (ctx->nb_streams < 1) {
152  fprintf(stderr, "No streams found in %s\n", file);
153  goto fail;
154  }
155  if (ctx->nb_streams > 1)
156  tracks->multiple_tracks_per_file = 1;
157 
158  for (i = 0; i < ctx->nb_streams; i++) {
159  struct Track **temp;
160  AVStream *st = ctx->streams[i];
161 
162  if (st->codec->bit_rate == 0) {
163  fprintf(stderr, "Skipping track %d in %s as it has zero bitrate\n",
164  st->id, file);
165  continue;
166  }
167 
168  track = av_mallocz(sizeof(*track));
169  if (!track) {
170  err = AVERROR(ENOMEM);
171  goto fail;
172  }
173  temp = av_realloc(tracks->tracks,
174  sizeof(*tracks->tracks) * (tracks->nb_tracks + 1));
175  if (!temp) {
176  av_free(track);
177  err = AVERROR(ENOMEM);
178  goto fail;
179  }
180  tracks->tracks = temp;
181  tracks->tracks[tracks->nb_tracks] = track;
182 
183  track->name = file;
184  if ((ptr = strrchr(file, '/')))
185  track->name = ptr + 1;
186 
187  track->bitrate = st->codec->bit_rate;
188  track->track_id = st->id;
189  track->timescale = st->time_base.den;
190  track->duration = st->duration;
191  track->is_audio = st->codec->codec_type == AVMEDIA_TYPE_AUDIO;
192  track->is_video = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;
193 
194  if (!track->is_audio && !track->is_video) {
195  fprintf(stderr,
196  "Track %d in %s is neither video nor audio, skipping\n",
197  track->track_id, file);
198  av_freep(&tracks->tracks[tracks->nb_tracks]);
199  continue;
200  }
201 
202  tracks->duration = FFMAX(tracks->duration,
204  track->timescale, AV_ROUND_UP));
205 
206  if (track->is_audio) {
207  track->channels = st->codec->channels;
208  track->sample_rate = st->codec->sample_rate;
209  }
210  if (track->is_video) {
211  track->width = st->codec->width;
212  track->height = st->codec->height;
213  }
214  set_codec_str(st->codec, track->codec_str, sizeof(track->codec_str));
215 
216  tracks->nb_tracks++;
217  }
218 
219  avformat_close_input(&ctx);
220 
221  err = find_sidx(tracks, orig_tracks, file);
222 
223 fail:
224  if (ctx)
225  avformat_close_input(&ctx);
226  return err;
227 }
228 
229 static void write_time(FILE *out, int64_t time, int decimals, enum AVRounding round)
230 {
231  int seconds = time / AV_TIME_BASE;
232  int fractions = time % AV_TIME_BASE;
233  int minutes = seconds / 60;
234  int hours = minutes / 60;
235  fractions = av_rescale_rnd(fractions, pow(10, decimals), AV_TIME_BASE, round);
236  seconds %= 60;
237  minutes %= 60;
238  fprintf(out, "PT");
239  if (hours)
240  fprintf(out, "%dH", hours);
241  if (hours || minutes)
242  fprintf(out, "%dM", minutes);
243  fprintf(out, "%d.%0*dS", seconds, decimals, fractions);
244 }
245 
246 static int output_mpd(struct Tracks *tracks, const char *filename)
247 {
248  FILE *out;
249  int i, j, ret = 0;
250  struct Track **adaptation_sets_buf[2] = { NULL };
251  struct Track ***adaptation_sets;
252  int nb_tracks_buf[2] = { 0 };
253  int *nb_tracks;
254  int set, nb_sets;
255  int64_t latest_start = 0;
256 
257  if (!tracks->multiple_tracks_per_file) {
258  adaptation_sets = adaptation_sets_buf;
259  nb_tracks = nb_tracks_buf;
260  nb_sets = 2;
261  for (i = 0; i < 2; i++) {
262  adaptation_sets[i] = av_malloc(sizeof(*adaptation_sets[i]) * tracks->nb_tracks);
263  if (!adaptation_sets[i]) {
264  ret = AVERROR(ENOMEM);
265  goto err;
266  }
267  }
268  for (i = 0; i < tracks->nb_tracks; i++) {
269  int set_index = -1;
270  if (tracks->tracks[i]->is_video)
271  set_index = 0;
272  else if (tracks->tracks[i]->is_audio)
273  set_index = 1;
274  else
275  continue;
276  adaptation_sets[set_index][nb_tracks[set_index]++] = tracks->tracks[i];
277  }
278  } else {
279  adaptation_sets = &tracks->tracks;
280  nb_tracks = &tracks->nb_tracks;
281  nb_sets = 1;
282  }
283 
284  out = fopen(filename, "w");
285  if (!out) {
286  ret = AVERROR(errno);
287  perror(filename);
288  return ret;
289  }
290  fprintf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
291  fprintf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
292  "\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n"
293  "\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
294  "\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n"
295  "\tprofiles=\"urn:mpeg:dash:profile:isoff-on-demand:2011\"\n"
296  "\ttype=\"static\"\n");
297  fprintf(out, "\tmediaPresentationDuration=\"");
298  write_time(out, tracks->duration, 1, AV_ROUND_DOWN);
299  fprintf(out, "\"\n");
300  fprintf(out, "\tminBufferTime=\"PT5S\">\n");
301 
302  for (i = 0; i < tracks->nb_tracks; i++) {
303  int64_t start = av_rescale_rnd(tracks->tracks[i]->earliest_presentation,
304  AV_TIME_BASE,
306  AV_ROUND_UP);
307  latest_start = FFMAX(start, latest_start);
308  }
309  fprintf(out, "\t<Period start=\"");
310  write_time(out, latest_start, 3, AV_ROUND_UP);
311  fprintf(out, "\">\n");
312 
313 
314  for (set = 0; set < nb_sets; set++) {
315  if (nb_tracks[set] == 0)
316  continue;
317  fprintf(out, "\t\t<AdaptationSet segmentAlignment=\"true\">\n");
318  if (nb_sets == 1) {
319  for (i = 0; i < nb_tracks[set]; i++) {
320  struct Track *track = adaptation_sets[set][i];
321  if (strcmp(track->name, adaptation_sets[set][0]->name))
322  break;
323  fprintf(out, "\t\t\t<ContentComponent id=\"%d\" contentType=\"%s\" />\n", track->track_id, track->is_audio ? "audio" : "video");
324  }
325  }
326 
327  for (i = 0; i < nb_tracks[set]; ) {
328  struct Track *first_track = adaptation_sets[set][i];
329  int width = 0, height = 0, sample_rate = 0, channels = 0, bitrate = 0;
330  fprintf(out, "\t\t\t<Representation id=\"%d\" codecs=\"", i);
331  for (j = i; j < nb_tracks[set]; j++) {
332  struct Track *track = adaptation_sets[set][j];
333  if (strcmp(track->name, first_track->name))
334  break;
335  if (track->is_audio) {
336  sample_rate = track->sample_rate;
337  channels = track->channels;
338  }
339  if (track->is_video) {
340  width = track->width;
341  height = track->height;
342  }
343  bitrate += track->bitrate;
344  if (j > i)
345  fprintf(out, ",");
346  fprintf(out, "%s", track->codec_str);
347  }
348  fprintf(out, "\" mimeType=\"%s/mp4\" bandwidth=\"%d\"",
349  width ? "video" : "audio", bitrate);
350  if (width > 0 && height > 0)
351  fprintf(out, " width=\"%d\" height=\"%d\"", width, height);
352  if (sample_rate > 0)
353  fprintf(out, " audioSamplingRate=\"%d\"", sample_rate);
354  fprintf(out, ">\n");
355  if (channels > 0)
356  fprintf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", channels);
357  fprintf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", first_track->name);
358  fprintf(out, "\t\t\t\t<SegmentBase indexRange=\"%"PRId64"-%"PRId64"\" />\n", first_track->sidx_start, first_track->sidx_start + first_track->sidx_length - 1);
359  fprintf(out, "\t\t\t</Representation>\n");
360  i = j;
361  }
362  fprintf(out, "\t\t</AdaptationSet>\n");
363  }
364  fprintf(out, "\t</Period>\n");
365  fprintf(out, "</MPD>\n");
366 
367  fclose(out);
368 err:
369  for (i = 0; i < 2; i++)
370  av_free(adaptation_sets_buf[i]);
371  return ret;
372 }
373 
374 static void clean_tracks(struct Tracks *tracks)
375 {
376  int i;
377  for (i = 0; i < tracks->nb_tracks; i++) {
378  av_freep(&tracks->tracks[i]);
379  }
380  av_freep(&tracks->tracks);
381  tracks->nb_tracks = 0;
382 }
383 
384 int main(int argc, char **argv)
385 {
386  const char *out = NULL;
387  struct Tracks tracks = { 0 };
388  int i;
389 
390  av_register_all();
391 
392  for (i = 1; i < argc; i++) {
393  if (!strcmp(argv[i], "-out")) {
394  out = argv[i + 1];
395  i++;
396  } else if (argv[i][0] == '-') {
397  return usage(argv[0], 1);
398  } else {
399  if (handle_file(&tracks, argv[i]))
400  return 1;
401  }
402  }
403  if (!tracks.nb_tracks || !out)
404  return usage(argv[0], 1);
405 
406  output_mpd(&tracks, out);
407 
408  clean_tracks(&tracks);
409 
410  return 0;
411 }