lavf: Add an MPEG-DASH ISOFF segmenting muxer
[libav.git] / libavformat / dashenc.c
CommitLineData
fe5e6e34
MS
1/*
2 * MPEG-DASH ISO BMFF segmenter
3 * Copyright (c) 2014 Martin Storsjo
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "config.h"
23#if HAVE_UNISTD_H
24#include <unistd.h>
25#endif
26
27#include "libavutil/avstring.h"
28#include "libavutil/intreadwrite.h"
29#include "libavutil/mathematics.h"
30#include "libavutil/opt.h"
31#include "libavutil/time_internal.h"
32
33#include "avc.h"
34#include "avformat.h"
35#include "avio_internal.h"
36#include "internal.h"
37#include "isom.h"
38#include "os_support.h"
39#include "url.h"
40
41typedef struct Segment {
42 char file[1024];
43 int64_t start_pos;
44 int range_length, index_length;
45 int64_t time;
46 int duration;
47 int n;
48} Segment;
49
50typedef struct OutputStream {
51 AVFormatContext *ctx;
52 int ctx_inited;
53 uint8_t iobuf[32768];
54 URLContext *out;
55 int packets_written;
56 char initfile[1024];
57 int64_t init_start_pos;
58 int init_range_length;
59 int nb_segments, segments_size, segment_index;
60 Segment **segments;
61 int64_t first_dts, start_dts, end_dts;
62
63 char codec_str[100];
64} OutputStream;
65
66typedef struct DASHContext {
67 const AVClass *class; /* Class for private options. */
68 int window_size;
69 int extra_window_size;
70 int min_seg_duration;
71 int remove_at_exit;
72 int use_template;
73 int use_timeline;
74 int single_file;
75 OutputStream *streams;
76 int has_video, has_audio;
77 int nb_segments;
78 int last_duration;
79 int total_duration;
80 char availability_start_time[100];
81 char dirname[1024];
82} DASHContext;
83
84static int dash_write(void *opaque, uint8_t *buf, int buf_size)
85{
86 OutputStream *os = opaque;
87 if (os->out)
88 ffurl_write(os->out, buf, buf_size);
89 return buf_size;
90}
91
92// RFC 6381
93static void set_codec_str(AVFormatContext *s, AVCodecContext *codec,
94 char *str, int size)
95{
96 const AVCodecTag *tags[2] = { NULL, NULL };
97 uint32_t tag;
98 if (codec->codec_type == AVMEDIA_TYPE_VIDEO)
99 tags[0] = ff_codec_movvideo_tags;
100 else if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
101 tags[0] = ff_codec_movaudio_tags;
102 else
103 return;
104
105 tag = av_codec_get_tag(tags, codec->codec_id);
106 if (!tag)
107 return;
108 if (size < 5)
109 return;
110
111 AV_WL32(str, tag);
112 str[4] = '\0';
113 if (!strcmp(str, "mp4a") || !strcmp(str, "mp4v")) {
114 uint32_t oti;
115 tags[0] = ff_mp4_obj_type;
116 oti = av_codec_get_tag(tags, codec->codec_id);
117 if (oti)
118 av_strlcatf(str, size, ".%02x", oti);
119 else
120 return;
121
122 if (tag == MKTAG('m', 'p', '4', 'a')) {
123 if (codec->extradata_size >= 2) {
124 int aot = codec->extradata[0] >> 3;
125 if (aot == 31)
126 aot = ((AV_RB16(codec->extradata) >> 5) & 0x3f) + 32;
127 av_strlcatf(str, size, ".%d", aot);
128 }
129 } else if (tag == MKTAG('m', 'p', '4', 'v')) {
130 // Unimplemented, should output ProfileLevelIndication as a decimal number
131 av_log(s, AV_LOG_WARNING, "Incomplete RFC 6381 codec string for mp4v\n");
132 }
133 } else if (!strcmp(str, "avc1")) {
134 uint8_t *tmpbuf = NULL;
135 uint8_t *extradata = codec->extradata;
136 int extradata_size = codec->extradata_size;
137 if (!extradata_size)
138 return;
139 if (extradata[0] != 1) {
140 AVIOContext *pb;
141 if (avio_open_dyn_buf(&pb) < 0)
142 return;
143 if (ff_isom_write_avcc(pb, extradata, extradata_size) < 0) {
144 avio_close_dyn_buf(pb, &tmpbuf);
145 av_free(tmpbuf);
146 return;
147 }
148 extradata_size = avio_close_dyn_buf(pb, &extradata);
149 tmpbuf = extradata;
150 }
151
152 if (extradata_size >= 4)
153 av_strlcatf(str, size, ".%02x%02x%02x",
154 extradata[1], extradata[2], extradata[3]);
155 av_free(tmpbuf);
156 }
157}
158
159static void dash_free(AVFormatContext *s)
160{
161 DASHContext *c = s->priv_data;
162 int i, j;
163 if (!c->streams)
164 return;
165 for (i = 0; i < s->nb_streams; i++) {
166 OutputStream *os = &c->streams[i];
167 if (os->ctx && os->ctx_inited)
168 av_write_trailer(os->ctx);
169 if (os->ctx && os->ctx->pb)
170 av_free(os->ctx->pb);
171 ffurl_close(os->out);
172 os->out = NULL;
173 if (os->ctx)
174 avformat_free_context(os->ctx);
175 for (j = 0; j < os->nb_segments; j++)
176 av_free(os->segments[j]);
177 av_free(os->segments);
178 }
179 av_freep(&c->streams);
180}
181
182static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c)
183{
184 int i, start_index = 0, start_number = 1;
185 if (c->window_size) {
186 start_index = FFMAX(os->nb_segments - c->window_size, 0);
187 start_number = FFMAX(os->segment_index - c->window_size, 1);
188 }
189
190 if (c->use_template) {
191 int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE;
192 avio_printf(out, "\t\t\t\t<SegmentTemplate timescale=\"%d\" ", timescale);
193 if (!c->use_timeline)
194 avio_printf(out, "duration=\"%d\" ", c->last_duration);
195 avio_printf(out, "initialization=\"init-stream$RepresentationID$.m4s\" media=\"chunk-stream$RepresentationID$-$Number%%05d$.m4s\" startNumber=\"%d\">\n", c->use_timeline ? start_number : 1);
196 if (c->use_timeline) {
197 avio_printf(out, "\t\t\t\t\t<SegmentTimeline>\n");
198 for (i = start_index; i < os->nb_segments; ) {
199 Segment *seg = os->segments[i];
200 int repeat = 0;
201 avio_printf(out, "\t\t\t\t\t\t<S ");
202 if (i == start_index)
203 avio_printf(out, "t=\"%"PRId64"\" ", seg->time);
204 avio_printf(out, "d=\"%d\" ", seg->duration);
205 while (i + repeat + 1 < os->nb_segments && os->segments[i + repeat + 1]->duration == seg->duration)
206 repeat++;
207 if (repeat > 0)
208 avio_printf(out, "r=\"%d\" ", repeat);
209 avio_printf(out, "/>\n");
210 i += 1 + repeat;
211 }
212 avio_printf(out, "\t\t\t\t\t</SegmentTimeline>\n");
213 }
214 avio_printf(out, "\t\t\t\t</SegmentTemplate>\n");
215 } else if (c->single_file) {
216 avio_printf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", os->initfile);
217 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%d\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
218 avio_printf(out, "\t\t\t\t\t<Initialization range=\"%"PRId64"-%"PRId64"\" />\n", os->init_start_pos, os->init_start_pos + os->init_range_length - 1);
219 for (i = start_index; i < os->nb_segments; i++) {
220 Segment *seg = os->segments[i];
221 avio_printf(out, "\t\t\t\t\t<SegmentURL mediaRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->range_length - 1);
222 if (seg->index_length)
223 avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1);
224 avio_printf(out, "/>\n");
225 }
226 avio_printf(out, "\t\t\t\t</SegmentList>\n");
227 } else {
228 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%d\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
229 avio_printf(out, "\t\t\t\t\t<Initialization sourceURL=\"%s\" />\n", os->initfile);
230 for (i = start_index; i < os->nb_segments; i++) {
231 Segment *seg = os->segments[i];
232 avio_printf(out, "\t\t\t\t\t<SegmentURL media=\"%s\" />\n", seg->file);
233 }
234 avio_printf(out, "\t\t\t\t</SegmentList>\n");
235 }
236}
237
238static char *xmlescape(const char *str) {
239 int outlen = strlen(str)*3/2 + 6;
240 char *out = av_realloc(NULL, outlen + 1);
241 int pos = 0;
242 if (!out)
243 return NULL;
244 for (; *str; str++) {
245 if (pos + 6 > outlen) {
246 char *tmp;
247 outlen = 2 * outlen + 6;
248 tmp = av_realloc(out, outlen + 1);
249 if (!tmp) {
250 av_free(out);
251 return NULL;
252 }
253 out = tmp;
254 }
255 if (*str == '&') {
256 memcpy(&out[pos], "&amp;", 5);
257 pos += 5;
258 } else if (*str == '<') {
259 memcpy(&out[pos], "&lt;", 4);
260 pos += 4;
261 } else if (*str == '>') {
262 memcpy(&out[pos], "&gt;", 4);
263 pos += 4;
264 } else if (*str == '\'') {
265 memcpy(&out[pos], "&apos;", 6);
266 pos += 6;
267 } else if (*str == '\"') {
268 memcpy(&out[pos], "&quot;", 6);
269 pos += 6;
270 } else {
271 out[pos++] = *str;
272 }
273 }
274 out[pos] = '\0';
275 return out;
276}
277
278static void write_time(AVIOContext *out, int64_t time)
279{
280 int seconds = time / AV_TIME_BASE;
281 int fractions = time % AV_TIME_BASE;
282 int minutes = seconds / 60;
283 int hours = minutes / 60;
284 seconds %= 60;
285 minutes %= 60;
286 avio_printf(out, "PT");
287 if (hours)
288 avio_printf(out, "%dH", hours);
289 if (hours || minutes)
290 avio_printf(out, "%dM", minutes);
291 avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10));
292}
293
294static int write_manifest(AVFormatContext *s, int final)
295{
296 DASHContext *c = s->priv_data;
297 AVIOContext *out;
298 char temp_filename[1024];
299 int ret, i;
300 AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0);
301
302 snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename);
303 ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
304 if (ret < 0) {
305 av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
306 return ret;
307 }
308 avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
309 avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
310 "\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n"
311 "\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
312 "\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n"
313 "\tprofiles=\"urn:mpeg:dash:profile:isoff-live:2011\"\n"
314 "\ttype=\"%s\"\n", final ? "static" : "dynamic");
315 if (final) {
316 avio_printf(out, "\tmediaPresentationDuration=\"");
317 write_time(out, c->total_duration);
318 avio_printf(out, "\"\n");
319 } else {
320 int update_period = c->last_duration / AV_TIME_BASE;
321 if (c->use_template && !c->use_timeline)
322 update_period = 500;
323 avio_printf(out, "\tminimumUpdatePeriod=\"PT%dS\"\n", update_period);
324 avio_printf(out, "\tsuggestedPresentationDelay=\"PT%dS\"\n", c->last_duration / AV_TIME_BASE);
325 if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) {
326 time_t t = time(NULL);
327 struct tm *ptm, tmbuf;
328 ptm = gmtime_r(&t, &tmbuf);
329 if (ptm) {
330 if (!strftime(c->availability_start_time, sizeof(c->availability_start_time),
331 "%Y-%m-%dT%H:%M:%S", ptm))
332 c->availability_start_time[0] = '\0';
333 }
334 }
335 if (c->availability_start_time[0])
336 avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time);
337 if (c->window_size && c->use_template) {
338 avio_printf(out, "\ttimeShiftBufferDepth=\"");
339 write_time(out, c->last_duration * c->window_size);
340 avio_printf(out, "\"\n");
341 }
342 }
343 avio_printf(out, "\tminBufferTime=\"");
344 write_time(out, c->last_duration);
345 avio_printf(out, "\">\n");
346 avio_printf(out, "\t<ProgramInformation>\n");
347 if (title) {
348 char *escaped = xmlescape(title->value);
349 avio_printf(out, "\t\t<Title>%s</Title>\n", escaped);
350 av_free(escaped);
351 }
352 avio_printf(out, "\t</ProgramInformation>\n");
353 if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) {
354 OutputStream *os = &c->streams[0];
355 int start_index = FFMAX(os->nb_segments - c->window_size, 0);
356 int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q);
357 avio_printf(out, "\t<Period start=\"");
358 write_time(out, start_time);
359 avio_printf(out, "\">\n");
360 } else {
361 avio_printf(out, "\t<Period start=\"PT0.0S\">\n");
362 }
363
364 if (c->has_video) {
365 avio_printf(out, "\t\t<AdaptationSet id=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
366 for (i = 0; i < s->nb_streams; i++) {
367 AVStream *st = s->streams[i];
368 OutputStream *os = &c->streams[i];
369 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_VIDEO)
370 continue;
371 avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"video/mp4\" codecs=\"%s\" bandwidth=\"%d\" width=\"%d\" height=\"%d\">\n", i, os->codec_str, st->codec->bit_rate, st->codec->width, st->codec->height);
372 output_segment_list(&c->streams[i], out, c);
373 avio_printf(out, "\t\t\t</Representation>\n");
374 }
375 avio_printf(out, "\t\t</AdaptationSet>\n");
376 }
377 if (c->has_audio) {
378 avio_printf(out, "\t\t<AdaptationSet id=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
379 for (i = 0; i < s->nb_streams; i++) {
380 AVStream *st = s->streams[i];
381 OutputStream *os = &c->streams[i];
382 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
383 continue;
384 avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"audio/mp4\" codecs=\"%s\" bandwidth=\"%d\" audioSamplingRate=\"%d\">\n", i, os->codec_str, st->codec->bit_rate, st->codec->sample_rate);
385 avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", st->codec->channels);
386 output_segment_list(&c->streams[i], out, c);
387 avio_printf(out, "\t\t\t</Representation>\n");
388 }
389 avio_printf(out, "\t\t</AdaptationSet>\n");
390 }
391 avio_printf(out, "\t</Period>\n");
392 avio_printf(out, "</MPD>\n");
393 avio_flush(out);
394 avio_close(out);
395 return ff_rename(temp_filename, s->filename);
396}
397
398static int dash_write_header(AVFormatContext *s)
399{
400 DASHContext *c = s->priv_data;
401 int ret = 0, i;
402 AVOutputFormat *oformat;
403 char *ptr;
404 char basename[1024];
405
406 if (c->single_file)
407 c->use_template = 0;
408
409 av_strlcpy(c->dirname, s->filename, sizeof(c->dirname));
410 ptr = strrchr(c->dirname, '/');
411 if (ptr) {
412 av_strlcpy(basename, &ptr[1], sizeof(basename));
413 ptr[1] = '\0';
414 } else {
415 c->dirname[0] = '\0';
416 av_strlcpy(basename, s->filename, sizeof(basename));
417 }
418
419 ptr = strrchr(basename, '.');
420 if (ptr)
421 *ptr = '\0';
422
423 oformat = av_guess_format("mp4", NULL, NULL);
424 if (!oformat) {
425 ret = AVERROR_MUXER_NOT_FOUND;
426 goto fail;
427 }
428
429 c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams);
430 if (!c->streams) {
431 ret = AVERROR(ENOMEM);
432 goto fail;
433 }
434
435 for (i = 0; i < s->nb_streams; i++) {
436 OutputStream *os = &c->streams[i];
437 AVFormatContext *ctx;
438 AVStream *st;
439 AVDictionary *opts = NULL;
440 char filename[1024];
441
442 if (!s->streams[i]->codec->bit_rate) {
443 av_log(s, AV_LOG_ERROR, "No bit rate set for stream %d\n", i);
444 ret = AVERROR(EINVAL);
445 goto fail;
446 }
447
448 ctx = avformat_alloc_context();
449 if (!ctx) {
450 ret = AVERROR(ENOMEM);
451 goto fail;
452 }
453 os->ctx = ctx;
454 ctx->oformat = oformat;
455 ctx->interrupt_callback = s->interrupt_callback;
456
457 if (!(st = avformat_new_stream(ctx, NULL))) {
458 ret = AVERROR(ENOMEM);
459 goto fail;
460 }
461 avcodec_copy_context(st->codec, s->streams[i]->codec);
462 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
463 st->time_base = s->streams[i]->time_base;
464 ctx->avoid_negative_ts = s->avoid_negative_ts;
465
466 ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL);
467 if (!ctx->pb) {
468 ret = AVERROR(ENOMEM);
469 goto fail;
470 }
471
472 if (c->single_file)
473 snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i);
474 else
475 snprintf(os->initfile, sizeof(os->initfile), "init-stream%d.m4s", i);
476 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
477 ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
478 if (ret < 0)
479 goto fail;
480 os->init_start_pos = 0;
481
482 av_dict_set(&opts, "movflags", "frag_custom+dash", 0);
483 if ((ret = avformat_write_header(ctx, &opts)) < 0) {
484 goto fail;
485 }
486 os->ctx_inited = 1;
487 avio_flush(ctx->pb);
488 av_dict_free(&opts);
489
490 if (c->single_file) {
491 os->init_range_length = avio_tell(ctx->pb);
492 } else {
493 ffurl_close(os->out);
494 os->out = NULL;
495 }
496
497 s->streams[i]->time_base = st->time_base;
498 // If the muxer wants to shift timestamps, request to have them shifted
499 // already before being handed to this muxer, so we don't have mismatches
500 // between the MPD and the actual segments.
501 s->avoid_negative_ts = ctx->avoid_negative_ts;
502 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
503 c->has_video = 1;
504 else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
505 c->has_audio = 1;
506
507 set_codec_str(s, os->ctx->streams[0]->codec, os->codec_str, sizeof(os->codec_str));
508 os->first_dts = AV_NOPTS_VALUE;
509 os->segment_index = 1;
510 }
511
512 if (!c->has_video && c->min_seg_duration <= 0) {
513 av_log(s, AV_LOG_WARNING, "no video stream and no min seg duration set\n");
514 ret = AVERROR(EINVAL);
515 }
516 ret = write_manifest(s, 0);
517
518fail:
519 if (ret)
520 dash_free(s);
521 return ret;
522}
523
524static int add_segment(OutputStream *os, const char *file,
525 int64_t time, int duration,
526 int64_t start_pos, int64_t range_length,
527 int64_t index_length)
528{
529 int err;
530 Segment *seg;
531 if (os->nb_segments >= os->segments_size) {
532 os->segments_size = (os->segments_size + 1) * 2;
533 if ((err = av_reallocp(&os->segments, sizeof(*os->segments) *
534 os->segments_size)) < 0) {
535 os->segments_size = 0;
536 os->nb_segments = 0;
537 return err;
538 }
539 }
540 seg = av_mallocz(sizeof(*seg));
541 if (!seg)
542 return AVERROR(ENOMEM);
543 av_strlcpy(seg->file, file, sizeof(seg->file));
544 seg->time = time;
545 seg->duration = duration;
546 seg->start_pos = start_pos;
547 seg->range_length = range_length;
548 seg->index_length = index_length;
549 os->segments[os->nb_segments++] = seg;
550 os->segment_index++;
551 return 0;
552}
553
554static void write_styp(AVIOContext *pb)
555{
556 avio_wb32(pb, 24);
557 ffio_wfourcc(pb, "styp");
558 ffio_wfourcc(pb, "msdh");
559 avio_wb32(pb, 0); /* minor */
560 ffio_wfourcc(pb, "msdh");
561 ffio_wfourcc(pb, "msix");
562}
563
564static void find_index_range(AVFormatContext *s, const char *dirname,
565 const char *filename, int64_t pos,
566 int *index_length)
567{
568 char full_path[1024];
569 uint8_t buf[8];
570 URLContext *fd;
571 int ret;
572
573 snprintf(full_path, sizeof(full_path), "%s%s", dirname, filename);
574 ret = ffurl_open(&fd, full_path, AVIO_FLAG_READ, &s->interrupt_callback, NULL);
575 if (ret < 0)
576 return;
577 if (ffurl_seek(fd, pos, SEEK_SET) != pos) {
578 ffurl_close(fd);
579 return;
580 }
581 ret = ffurl_read(fd, buf, 8);
582 ffurl_close(fd);
583 if (ret < 8)
584 return;
585 if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x'))
586 return;
587 *index_length = AV_RB32(&buf[0]);
588}
589
590static int dash_flush(AVFormatContext *s, int final)
591{
592 DASHContext *c = s->priv_data;
593 int i, ret = 0;
594
595 for (i = 0; i < s->nb_streams; i++) {
596 OutputStream *os = &c->streams[i];
597 char filename[1024] = "", full_path[1024], temp_path[1024];
598 int64_t start_pos = avio_tell(os->ctx->pb);
599 int range_length, index_length = 0;
600
601 if (!os->packets_written)
602 continue;
603
604 if (!c->single_file) {
605 snprintf(filename, sizeof(filename), "chunk-stream%d-%05d.m4s", i, os->segment_index);
606 snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename);
607 snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path);
608 ret = ffurl_open(&os->out, temp_path, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
609 if (ret < 0)
610 break;
611 write_styp(os->ctx->pb);
612 }
613 av_write_frame(os->ctx, NULL);
614 avio_flush(os->ctx->pb);
615 os->packets_written = 0;
616
617 range_length = avio_tell(os->ctx->pb) - start_pos;
618 if (c->single_file) {
619 find_index_range(s, c->dirname, os->initfile, start_pos, &index_length);
620 } else {
621 ffurl_close(os->out);
622 os->out = NULL;
623 ret = ff_rename(temp_path, full_path);
624 if (ret < 0)
625 break;
626 }
627 add_segment(os, filename, os->start_dts, os->end_dts - os->start_dts, start_pos, range_length, index_length);
628 }
629
630 if (c->window_size || (final && c->remove_at_exit)) {
631 for (i = 0; i < s->nb_streams; i++) {
632 OutputStream *os = &c->streams[i];
633 int j;
634 int remove = os->nb_segments - c->window_size - c->extra_window_size;
635 if (final && c->remove_at_exit)
636 remove = os->nb_segments;
637 if (remove > 0) {
638 for (j = 0; j < remove; j++) {
639 char filename[1024];
640 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file);
641 unlink(filename);
642 av_free(os->segments[j]);
643 }
644 os->nb_segments -= remove;
645 memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments));
646 }
647 }
648 }
649
650 if (ret >= 0)
651 ret = write_manifest(s, final);
652 return ret;
653}
654
655static int dash_write_packet(AVFormatContext *s, AVPacket *pkt)
656{
657 DASHContext *c = s->priv_data;
658 AVStream *st = s->streams[pkt->stream_index];
659 OutputStream *os = &c->streams[pkt->stream_index];
660 int64_t seg_end_duration = (c->nb_segments + 1) * (int64_t) c->min_seg_duration;
661 int ret;
662
663 // If forcing the stream to start at 0, the mp4 muxer will set the start
664 // timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps.
665 if (os->first_dts == AV_NOPTS_VALUE &&
666 s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) {
667 pkt->pts -= pkt->dts;
668 pkt->dts = 0;
669 }
670
671 if (os->first_dts == AV_NOPTS_VALUE)
672 os->first_dts = pkt->dts;
673
674 if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
675 pkt->flags & AV_PKT_FLAG_KEY && os->packets_written &&
676 av_compare_ts(pkt->dts - os->first_dts, st->time_base,
677 seg_end_duration, AV_TIME_BASE_Q) >= 0) {
678 int64_t prev_duration = c->last_duration;
679
680 c->last_duration = av_rescale_q(pkt->dts - os->start_dts,
681 st->time_base,
682 AV_TIME_BASE_Q);
683 c->total_duration = av_rescale_q(pkt->dts - os->first_dts,
684 st->time_base,
685 AV_TIME_BASE_Q);
686
687 if ((!c->use_timeline || !c->use_template) && prev_duration) {
688 if (c->last_duration < prev_duration*9/10 ||
689 c->last_duration > prev_duration*11/10) {
690 av_log(s, AV_LOG_WARNING,
691 "Segment durations differ too much, enable use_timeline "
692 "and use_template, or keep a stricter keyframe interval\n");
693 }
694 }
695
696 if ((ret = dash_flush(s, 0)) < 0)
697 return ret;
698 c->nb_segments++;
699 }
700
701 if (!os->packets_written)
702 os->start_dts = pkt->dts;
703 os->end_dts = pkt->dts + pkt->duration;
704 os->packets_written++;
705 return ff_write_chained(os->ctx, 0, pkt, s);
706}
707
708static int dash_write_trailer(AVFormatContext *s)
709{
710 DASHContext *c = s->priv_data;
711
712 if (s->nb_streams > 0) {
713 OutputStream *os = &c->streams[0];
714 // If no segments have been written so far, try to do a crude
715 // guess of the segment duration
716 if (!c->last_duration)
717 c->last_duration = av_rescale_q(os->end_dts - os->start_dts,
718 s->streams[0]->time_base,
719 AV_TIME_BASE_Q);
720 c->total_duration = av_rescale_q(os->end_dts - os->first_dts,
721 s->streams[0]->time_base,
722 AV_TIME_BASE_Q);
723 }
724 dash_flush(s, 1);
725
726 if (c->remove_at_exit) {
727 char filename[1024];
728 int i;
729 for (i = 0; i < s->nb_streams; i++) {
730 OutputStream *os = &c->streams[i];
731 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
732 unlink(filename);
733 }
734 unlink(s->filename);
735 }
736
737 dash_free(s);
738 return 0;
739}
740
741#define OFFSET(x) offsetof(DASHContext, x)
742#define E AV_OPT_FLAG_ENCODING_PARAM
743static const AVOption options[] = {
744 { "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
745 { "extra_window_size", "number of segments kept outside of the manifest before removing from disk", OFFSET(extra_window_size), AV_OPT_TYPE_INT, { .i64 = 5 }, 0, INT_MAX, E },
746 { "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E },
747 { "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
748 { "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
749 { "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
750 { "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
751 { NULL },
752};
753
754static const AVClass dash_class = {
755 .class_name = "dash muxer",
756 .item_name = av_default_item_name,
757 .option = options,
758 .version = LIBAVUTIL_VERSION_INT,
759};
760
761AVOutputFormat ff_dash_muxer = {
762 .name = "dash",
763 .long_name = NULL_IF_CONFIG_SMALL("DASH Muxer"),
764 .priv_data_size = sizeof(DASHContext),
765 .audio_codec = AV_CODEC_ID_AAC,
766 .video_codec = AV_CODEC_ID_H264,
767 .flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE,
768 .write_header = dash_write_header,
769 .write_packet = dash_write_packet,
770 .write_trailer = dash_write_trailer,
771 .codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
772 .priv_class = &dash_class,
773};