2 * MPEG-DASH ISO BMFF segmenter
3 * Copyright (c) 2014 Martin Storsjo
5 * This file is part of FFmpeg.
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.
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.
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
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"
35 #include "avio_internal.h"
38 #include "os_support.h"
41 // See ISO/IEC 23009-1:2014 5.3.9.4.4
43 DASH_TMPL_ID_UNDEFINED = -1,
47 DASH_TMPL_ID_BANDWIDTH,
51 typedef struct Segment {
54 int range_length, index_length;
60 typedef struct OutputStream {
67 int64_t init_start_pos;
68 int init_range_length;
69 int nb_segments, segments_size, segment_index;
71 int64_t first_dts, start_dts, end_dts;
73 char bandwidth_str[64];
78 typedef struct DASHContext {
79 const AVClass *class; /* Class for private options. */
81 int extra_window_size;
87 OutputStream *streams;
88 int has_video, has_audio;
89 int64_t last_duration;
90 int64_t total_duration;
91 char availability_start_time[100];
93 const char *single_file_name;
94 const char *init_seg_name;
95 const char *media_seg_name;
98 static int dash_write(void *opaque, uint8_t *buf, int buf_size)
100 OutputStream *os = opaque;
102 ffurl_write(os->out, buf, buf_size);
107 static void set_codec_str(AVFormatContext *s, AVCodecContext *codec,
110 const AVCodecTag *tags[2] = { NULL, NULL };
112 if (codec->codec_type == AVMEDIA_TYPE_VIDEO)
113 tags[0] = ff_codec_movvideo_tags;
114 else if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
115 tags[0] = ff_codec_movaudio_tags;
119 tag = av_codec_get_tag(tags, codec->codec_id);
127 if (!strcmp(str, "mp4a") || !strcmp(str, "mp4v")) {
129 tags[0] = ff_mp4_obj_type;
130 oti = av_codec_get_tag(tags, codec->codec_id);
132 av_strlcatf(str, size, ".%02x", oti);
136 if (tag == MKTAG('m', 'p', '4', 'a')) {
137 if (codec->extradata_size >= 2) {
138 int aot = codec->extradata[0] >> 3;
140 aot = ((AV_RB16(codec->extradata) >> 5) & 0x3f) + 32;
141 av_strlcatf(str, size, ".%d", aot);
143 } else if (tag == MKTAG('m', 'p', '4', 'v')) {
144 // Unimplemented, should output ProfileLevelIndication as a decimal number
145 av_log(s, AV_LOG_WARNING, "Incomplete RFC 6381 codec string for mp4v\n");
147 } else if (!strcmp(str, "avc1")) {
148 uint8_t *tmpbuf = NULL;
149 uint8_t *extradata = codec->extradata;
150 int extradata_size = codec->extradata_size;
153 if (extradata[0] != 1) {
155 if (avio_open_dyn_buf(&pb) < 0)
157 if (ff_isom_write_avcc(pb, extradata, extradata_size) < 0) {
158 avio_close_dyn_buf(pb, &tmpbuf);
162 extradata_size = avio_close_dyn_buf(pb, &extradata);
166 if (extradata_size >= 4)
167 av_strlcatf(str, size, ".%02x%02x%02x",
168 extradata[1], extradata[2], extradata[3]);
173 static void dash_free(AVFormatContext *s)
175 DASHContext *c = s->priv_data;
179 for (i = 0; i < s->nb_streams; i++) {
180 OutputStream *os = &c->streams[i];
181 if (os->ctx && os->ctx_inited)
182 av_write_trailer(os->ctx);
183 if (os->ctx && os->ctx->pb)
184 av_free(os->ctx->pb);
185 ffurl_close(os->out);
188 avformat_free_context(os->ctx);
189 for (j = 0; j < os->nb_segments; j++)
190 av_free(os->segments[j]);
191 av_free(os->segments);
193 av_freep(&c->streams);
196 static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c)
198 int i, start_index = 0, start_number = 1;
199 if (c->window_size) {
200 start_index = FFMAX(os->nb_segments - c->window_size, 0);
201 start_number = FFMAX(os->segment_index - c->window_size, 1);
204 if (c->use_template) {
205 int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE;
206 avio_printf(out, "\t\t\t\t<SegmentTemplate timescale=\"%d\" ", timescale);
207 if (!c->use_timeline)
208 avio_printf(out, "duration=\"%"PRId64"\" ", c->last_duration);
209 avio_printf(out, "initialization=\"%s\" media=\"%s\" startNumber=\"%d\">\n", c->init_seg_name, c->media_seg_name, c->use_timeline ? start_number : 1);
210 if (c->use_timeline) {
211 avio_printf(out, "\t\t\t\t\t<SegmentTimeline>\n");
212 for (i = start_index; i < os->nb_segments; ) {
213 Segment *seg = os->segments[i];
215 avio_printf(out, "\t\t\t\t\t\t<S ");
216 if (i == start_index)
217 avio_printf(out, "t=\"%"PRId64"\" ", seg->time);
218 avio_printf(out, "d=\"%d\" ", seg->duration);
219 while (i + repeat + 1 < os->nb_segments && os->segments[i + repeat + 1]->duration == seg->duration)
222 avio_printf(out, "r=\"%d\" ", repeat);
223 avio_printf(out, "/>\n");
226 avio_printf(out, "\t\t\t\t\t</SegmentTimeline>\n");
228 avio_printf(out, "\t\t\t\t</SegmentTemplate>\n");
229 } else if (c->single_file) {
230 avio_printf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", os->initfile);
231 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
232 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);
233 for (i = start_index; i < os->nb_segments; i++) {
234 Segment *seg = os->segments[i];
235 avio_printf(out, "\t\t\t\t\t<SegmentURL mediaRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->range_length - 1);
236 if (seg->index_length)
237 avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1);
238 avio_printf(out, "/>\n");
240 avio_printf(out, "\t\t\t\t</SegmentList>\n");
242 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
243 avio_printf(out, "\t\t\t\t\t<Initialization sourceURL=\"%s\" />\n", os->initfile);
244 for (i = start_index; i < os->nb_segments; i++) {
245 Segment *seg = os->segments[i];
246 avio_printf(out, "\t\t\t\t\t<SegmentURL media=\"%s\" />\n", seg->file);
248 avio_printf(out, "\t\t\t\t</SegmentList>\n");
252 static DASHTmplId dash_read_tmpl_id(const char *identifier, char *format_tag,
253 size_t format_tag_size, const char **ptr) {
254 const char *next_ptr;
255 DASHTmplId id_type = DASH_TMPL_ID_UNDEFINED;
257 if (av_strstart(identifier, "$$", &next_ptr)) {
258 id_type = DASH_TMPL_ID_ESCAPE;
260 } else if (av_strstart(identifier, "$RepresentationID$", &next_ptr)) {
261 id_type = DASH_TMPL_ID_REP_ID;
262 // default to basic format, as $RepresentationID$ identifiers
263 // are not allowed to have custom format-tags.
264 av_strlcpy(format_tag, "%d", format_tag_size);
266 } else { // the following identifiers may have an explicit format_tag
267 if (av_strstart(identifier, "$Number", &next_ptr))
268 id_type = DASH_TMPL_ID_NUMBER;
269 else if (av_strstart(identifier, "$Bandwidth", &next_ptr))
270 id_type = DASH_TMPL_ID_BANDWIDTH;
271 else if (av_strstart(identifier, "$Time", &next_ptr))
272 id_type = DASH_TMPL_ID_TIME;
274 id_type = DASH_TMPL_ID_UNDEFINED;
276 // next parse the dash format-tag and generate a c-string format tag
277 // (next_ptr now points at the first '%' at the beginning of the format-tag)
278 if (id_type != DASH_TMPL_ID_UNDEFINED) {
279 const char *number_format = DASH_TMPL_ID_TIME ? "lld" : "d";
280 if (next_ptr[0] == '$') { // no dash format-tag
281 snprintf(format_tag, format_tag_size, "%%%s", number_format);
284 const char *width_ptr;
285 // only tolerate single-digit width-field (i.e. up to 9-digit width)
286 if (av_strstart(next_ptr, "%0", &width_ptr) &&
287 av_isdigit(width_ptr[0]) &&
288 av_strstart(&width_ptr[1], "d$", &next_ptr)) {
289 // yes, we're using a format tag to build format_tag.
290 snprintf(format_tag, format_tag_size, "%s%c%s", "%0", width_ptr[0], number_format);
293 av_log(NULL, AV_LOG_WARNING, "Failed to parse format-tag beginning with %s. Expected either a "
294 "closing '$' character or a format-string like '%%0[width]d', "
295 "where width must be a single digit\n", next_ptr);
296 id_type = DASH_TMPL_ID_UNDEFINED;
304 static void dash_fill_tmpl_params(char *dst, size_t buffer_size,
305 const char *template, int rep_id,
306 int number, int bit_rate,
309 const char *t_cur = template;
310 while (dst_pos < buffer_size - 1 && *t_cur) {
311 char format_tag[7]; // May be "%d", "%0Xd", or "%0Xlld" (for $Time$), where X is in [0-9]
314 const char *t_next = strchr(t_cur, '$'); // copy over everything up to the first '$' character
316 int num_copy_bytes = FFMIN(t_next - t_cur, buffer_size - dst_pos - 1);
317 av_strlcpy(&dst[dst_pos], t_cur, num_copy_bytes + 1);
319 dst_pos += num_copy_bytes;
321 } else { // no more DASH identifiers to substitute - just copy the rest over and break
322 av_strlcpy(&dst[dst_pos], t_cur, buffer_size - dst_pos);
326 if (dst_pos >= buffer_size - 1 || !*t_cur)
329 // t_cur is now pointing to a '$' character
330 id_type = dash_read_tmpl_id(t_cur, format_tag, sizeof(format_tag), &t_next);
332 case DASH_TMPL_ID_ESCAPE:
333 av_strlcpy(&dst[dst_pos], "$", 2);
336 case DASH_TMPL_ID_REP_ID:
337 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, rep_id);
339 case DASH_TMPL_ID_NUMBER:
340 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, number);
342 case DASH_TMPL_ID_BANDWIDTH:
343 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, bit_rate);
345 case DASH_TMPL_ID_TIME:
346 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, time);
348 case DASH_TMPL_ID_UNDEFINED:
349 // copy over one byte and advance
350 av_strlcpy(&dst[dst_pos], t_cur, 2);
355 // t_next points just past the processed identifier
356 // n is the number of bytes that were attempted to be written to dst
357 // (may have failed to write all because buffer_size).
360 dst_pos += FFMIN(n, buffer_size - dst_pos - 1);
365 static char *xmlescape(const char *str) {
366 int outlen = strlen(str)*3/2 + 6;
367 char *out = av_realloc(NULL, outlen + 1);
371 for (; *str; str++) {
372 if (pos + 6 > outlen) {
374 outlen = 2 * outlen + 6;
375 tmp = av_realloc(out, outlen + 1);
383 memcpy(&out[pos], "&", 5);
385 } else if (*str == '<') {
386 memcpy(&out[pos], "<", 4);
388 } else if (*str == '>') {
389 memcpy(&out[pos], ">", 4);
391 } else if (*str == '\'') {
392 memcpy(&out[pos], "'", 6);
394 } else if (*str == '\"') {
395 memcpy(&out[pos], """, 6);
405 static void write_time(AVIOContext *out, int64_t time)
407 int seconds = time / AV_TIME_BASE;
408 int fractions = time % AV_TIME_BASE;
409 int minutes = seconds / 60;
410 int hours = minutes / 60;
413 avio_printf(out, "PT");
415 avio_printf(out, "%dH", hours);
416 if (hours || minutes)
417 avio_printf(out, "%dM", minutes);
418 avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10));
421 static int write_manifest(AVFormatContext *s, int final)
423 DASHContext *c = s->priv_data;
425 char temp_filename[1024];
427 AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0);
429 snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename);
430 ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
432 av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
435 avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
436 avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
437 "\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n"
438 "\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
439 "\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n"
440 "\tprofiles=\"urn:mpeg:dash:profile:isoff-live:2011\"\n"
441 "\ttype=\"%s\"\n", final ? "static" : "dynamic");
443 avio_printf(out, "\tmediaPresentationDuration=\"");
444 write_time(out, c->total_duration);
445 avio_printf(out, "\"\n");
447 int64_t update_period = c->last_duration / AV_TIME_BASE;
448 if (c->use_template && !c->use_timeline)
450 avio_printf(out, "\tminimumUpdatePeriod=\"PT%"PRId64"S\"\n", update_period);
451 avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE);
452 if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) {
453 time_t t = time(NULL);
454 struct tm *ptm, tmbuf;
455 ptm = gmtime_r(&t, &tmbuf);
457 if (!strftime(c->availability_start_time, sizeof(c->availability_start_time),
458 "%Y-%m-%dT%H:%M:%S", ptm))
459 c->availability_start_time[0] = '\0';
462 if (c->availability_start_time[0])
463 avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time);
464 if (c->window_size && c->use_template) {
465 avio_printf(out, "\ttimeShiftBufferDepth=\"");
466 write_time(out, c->last_duration * c->window_size);
467 avio_printf(out, "\"\n");
470 avio_printf(out, "\tminBufferTime=\"");
471 write_time(out, c->last_duration);
472 avio_printf(out, "\">\n");
473 avio_printf(out, "\t<ProgramInformation>\n");
475 char *escaped = xmlescape(title->value);
476 avio_printf(out, "\t\t<Title>%s</Title>\n", escaped);
479 avio_printf(out, "\t</ProgramInformation>\n");
480 if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) {
481 OutputStream *os = &c->streams[0];
482 int start_index = FFMAX(os->nb_segments - c->window_size, 0);
483 int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q);
484 avio_printf(out, "\t<Period start=\"");
485 write_time(out, start_time);
486 avio_printf(out, "\">\n");
488 avio_printf(out, "\t<Period start=\"PT0.0S\">\n");
492 avio_printf(out, "\t\t<AdaptationSet id=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
493 for (i = 0; i < s->nb_streams; i++) {
494 AVStream *st = s->streams[i];
495 OutputStream *os = &c->streams[i];
496 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_VIDEO)
498 avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"video/mp4\" codecs=\"%s\"%s width=\"%d\" height=\"%d\">\n", i, os->codec_str, os->bandwidth_str, st->codec->width, st->codec->height);
499 output_segment_list(&c->streams[i], out, c);
500 avio_printf(out, "\t\t\t</Representation>\n");
502 avio_printf(out, "\t\t</AdaptationSet>\n");
505 avio_printf(out, "\t\t<AdaptationSet id=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
506 for (i = 0; i < s->nb_streams; i++) {
507 AVStream *st = s->streams[i];
508 OutputStream *os = &c->streams[i];
509 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
511 avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"audio/mp4\" codecs=\"%s\"%s audioSamplingRate=\"%d\">\n", i, os->codec_str, os->bandwidth_str, st->codec->sample_rate);
512 avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", st->codec->channels);
513 output_segment_list(&c->streams[i], out, c);
514 avio_printf(out, "\t\t\t</Representation>\n");
516 avio_printf(out, "\t\t</AdaptationSet>\n");
518 avio_printf(out, "\t</Period>\n");
519 avio_printf(out, "</MPD>\n");
522 return ff_rename(temp_filename, s->filename, s);
525 static int dash_write_header(AVFormatContext *s)
527 DASHContext *c = s->priv_data;
529 AVOutputFormat *oformat;
533 if (c->single_file_name)
538 av_strlcpy(c->dirname, s->filename, sizeof(c->dirname));
539 ptr = strrchr(c->dirname, '/');
541 av_strlcpy(basename, &ptr[1], sizeof(basename));
544 c->dirname[0] = '\0';
545 av_strlcpy(basename, s->filename, sizeof(basename));
548 ptr = strrchr(basename, '.');
552 oformat = av_guess_format("mp4", NULL, NULL);
554 ret = AVERROR_MUXER_NOT_FOUND;
558 c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams);
560 ret = AVERROR(ENOMEM);
564 for (i = 0; i < s->nb_streams; i++) {
565 OutputStream *os = &c->streams[i];
566 AVFormatContext *ctx;
568 AVDictionary *opts = NULL;
571 os->bit_rate = s->streams[i]->codec->bit_rate ?
572 s->streams[i]->codec->bit_rate :
573 s->streams[i]->codec->rc_max_rate;
575 snprintf(os->bandwidth_str, sizeof(os->bandwidth_str),
576 " bandwidth=\"%d\"", os->bit_rate);
578 int level = s->strict_std_compliance >= FF_COMPLIANCE_STRICT ?
579 AV_LOG_ERROR : AV_LOG_WARNING;
580 av_log(s, level, "No bit rate set for stream %d\n", i);
581 if (s->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
582 ret = AVERROR(EINVAL);
587 ctx = avformat_alloc_context();
589 ret = AVERROR(ENOMEM);
593 ctx->oformat = oformat;
594 ctx->interrupt_callback = s->interrupt_callback;
596 if (!(st = avformat_new_stream(ctx, NULL))) {
597 ret = AVERROR(ENOMEM);
600 avcodec_copy_context(st->codec, s->streams[i]->codec);
601 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
602 st->time_base = s->streams[i]->time_base;
603 ctx->avoid_negative_ts = s->avoid_negative_ts;
605 ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL);
607 ret = AVERROR(ENOMEM);
611 if (c->single_file) {
612 if (c->single_file_name)
613 dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->single_file_name, i, 0, os->bit_rate, 0);
615 snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i);
617 dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->init_seg_name, i, 0, os->bit_rate, 0);
619 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
620 ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
623 os->init_start_pos = 0;
625 av_dict_set(&opts, "movflags", "frag_custom+dash", 0);
626 if ((ret = avformat_write_header(ctx, &opts)) < 0) {
633 if (c->single_file) {
634 os->init_range_length = avio_tell(ctx->pb);
636 ffurl_close(os->out);
639 av_log(s, AV_LOG_VERBOSE, "Representation %d init segment written to: %s\n", i, filename);
641 s->streams[i]->time_base = st->time_base;
642 // If the muxer wants to shift timestamps, request to have them shifted
643 // already before being handed to this muxer, so we don't have mismatches
644 // between the MPD and the actual segments.
645 s->avoid_negative_ts = ctx->avoid_negative_ts;
646 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
648 else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
651 set_codec_str(s, os->ctx->streams[0]->codec, os->codec_str, sizeof(os->codec_str));
652 os->first_dts = AV_NOPTS_VALUE;
653 os->segment_index = 1;
656 if (!c->has_video && c->min_seg_duration <= 0) {
657 av_log(s, AV_LOG_WARNING, "no video stream and no min seg duration set\n");
658 ret = AVERROR(EINVAL);
660 ret = write_manifest(s, 0);
662 av_log(s, AV_LOG_VERBOSE, "Manifest written to: %s\n", s->filename);
670 static int add_segment(OutputStream *os, const char *file,
671 int64_t time, int duration,
672 int64_t start_pos, int64_t range_length,
673 int64_t index_length)
677 if (os->nb_segments >= os->segments_size) {
678 os->segments_size = (os->segments_size + 1) * 2;
679 if ((err = av_reallocp(&os->segments, sizeof(*os->segments) *
680 os->segments_size)) < 0) {
681 os->segments_size = 0;
686 seg = av_mallocz(sizeof(*seg));
688 return AVERROR(ENOMEM);
689 av_strlcpy(seg->file, file, sizeof(seg->file));
691 seg->duration = duration;
692 seg->start_pos = start_pos;
693 seg->range_length = range_length;
694 seg->index_length = index_length;
695 os->segments[os->nb_segments++] = seg;
700 static void write_styp(AVIOContext *pb)
703 ffio_wfourcc(pb, "styp");
704 ffio_wfourcc(pb, "msdh");
705 avio_wb32(pb, 0); /* minor */
706 ffio_wfourcc(pb, "msdh");
707 ffio_wfourcc(pb, "msix");
710 static void find_index_range(AVFormatContext *s, const char *full_path,
711 int64_t pos, int *index_length)
717 ret = ffurl_open(&fd, full_path, AVIO_FLAG_READ, &s->interrupt_callback, NULL);
720 if (ffurl_seek(fd, pos, SEEK_SET) != pos) {
724 ret = ffurl_read(fd, buf, 8);
728 if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x'))
730 *index_length = AV_RB32(&buf[0]);
733 static int dash_flush(AVFormatContext *s, int final, int stream)
735 DASHContext *c = s->priv_data;
737 int cur_flush_segment_index = 0;
739 cur_flush_segment_index = c->streams[stream].segment_index;
741 for (i = 0; i < s->nb_streams; i++) {
742 OutputStream *os = &c->streams[i];
743 char filename[1024] = "", full_path[1024], temp_path[1024];
744 int64_t start_pos = avio_tell(os->ctx->pb);
745 int range_length, index_length = 0;
747 if (!os->packets_written)
750 // Flush the single stream that got a keyframe right now.
751 // Flush all audio streams as well, in sync with video keyframes,
752 // but not the other video streams.
753 if (stream >= 0 && i != stream) {
754 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
756 // Make sure we don't flush audio streams multiple times, when
757 // all video streams are flushed one at a time.
758 if (c->has_video && os->segment_index > cur_flush_segment_index)
762 if (!c->single_file) {
763 dash_fill_tmpl_params(filename, sizeof(filename), c->media_seg_name, i, os->segment_index, os->bit_rate, os->start_dts);
764 snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename);
765 snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path);
766 ret = ffurl_open(&os->out, temp_path, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
769 write_styp(os->ctx->pb);
771 snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, os->initfile);
774 av_write_frame(os->ctx, NULL);
775 avio_flush(os->ctx->pb);
776 os->packets_written = 0;
778 range_length = avio_tell(os->ctx->pb) - start_pos;
779 if (c->single_file) {
780 find_index_range(s, full_path, start_pos, &index_length);
782 ffurl_close(os->out);
784 ret = ff_rename(temp_path, full_path, s);
788 add_segment(os, filename, os->start_dts, os->end_dts - os->start_dts, start_pos, range_length, index_length);
789 av_log(s, AV_LOG_VERBOSE, "Representation %d media segment %d written to: %s\n", i, os->segment_index, full_path);
792 if (c->window_size || (final && c->remove_at_exit)) {
793 for (i = 0; i < s->nb_streams; i++) {
794 OutputStream *os = &c->streams[i];
796 int remove = os->nb_segments - c->window_size - c->extra_window_size;
797 if (final && c->remove_at_exit)
798 remove = os->nb_segments;
800 for (j = 0; j < remove; j++) {
802 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file);
804 av_free(os->segments[j]);
806 os->nb_segments -= remove;
807 memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments));
813 ret = write_manifest(s, final);
817 static int dash_write_packet(AVFormatContext *s, AVPacket *pkt)
819 DASHContext *c = s->priv_data;
820 AVStream *st = s->streams[pkt->stream_index];
821 OutputStream *os = &c->streams[pkt->stream_index];
822 int64_t seg_end_duration = (os->segment_index) * (int64_t) c->min_seg_duration;
825 // If forcing the stream to start at 0, the mp4 muxer will set the start
826 // timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps.
827 if (os->first_dts == AV_NOPTS_VALUE &&
828 s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) {
829 pkt->pts -= pkt->dts;
833 if (os->first_dts == AV_NOPTS_VALUE)
834 os->first_dts = pkt->dts;
836 if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
837 pkt->flags & AV_PKT_FLAG_KEY && os->packets_written &&
838 av_compare_ts(pkt->dts - os->first_dts, st->time_base,
839 seg_end_duration, AV_TIME_BASE_Q) >= 0) {
840 int64_t prev_duration = c->last_duration;
842 c->last_duration = av_rescale_q(pkt->dts - os->start_dts,
845 c->total_duration = av_rescale_q(pkt->dts - os->first_dts,
849 if ((!c->use_timeline || !c->use_template) && prev_duration) {
850 if (c->last_duration < prev_duration*9/10 ||
851 c->last_duration > prev_duration*11/10) {
852 av_log(s, AV_LOG_WARNING,
853 "Segment durations differ too much, enable use_timeline "
854 "and use_template, or keep a stricter keyframe interval\n");
858 if ((ret = dash_flush(s, 0, pkt->stream_index)) < 0)
862 if (!os->packets_written)
863 os->start_dts = pkt->dts;
864 os->end_dts = pkt->dts + pkt->duration;
865 os->packets_written++;
866 return ff_write_chained(os->ctx, 0, pkt, s, 0);
869 static int dash_write_trailer(AVFormatContext *s)
871 DASHContext *c = s->priv_data;
873 if (s->nb_streams > 0) {
874 OutputStream *os = &c->streams[0];
875 // If no segments have been written so far, try to do a crude
876 // guess of the segment duration
877 if (!c->last_duration)
878 c->last_duration = av_rescale_q(os->end_dts - os->start_dts,
879 s->streams[0]->time_base,
881 c->total_duration = av_rescale_q(os->end_dts - os->first_dts,
882 s->streams[0]->time_base,
885 dash_flush(s, 1, -1);
887 if (c->remove_at_exit) {
890 for (i = 0; i < s->nb_streams; i++) {
891 OutputStream *os = &c->streams[i];
892 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
902 #define OFFSET(x) offsetof(DASHContext, x)
903 #define E AV_OPT_FLAG_ENCODING_PARAM
904 static const AVOption options[] = {
905 { "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
906 { "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 },
907 { "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E },
908 { "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
909 { "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
910 { "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
911 { "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
912 { "single_file_name", "DASH-templated name to be used for baseURL. Implies storing all segments in one file, accessed using byte ranges", OFFSET(single_file_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
913 { "init_seg_name", "DASH-templated name to used for the initialization segment", OFFSET(init_seg_name), AV_OPT_TYPE_STRING, {.str = "init-stream$RepresentationID$.m4s"}, 0, 0, E },
914 { "media_seg_name", "DASH-templated name to used for the media segments", OFFSET(media_seg_name), AV_OPT_TYPE_STRING, {.str = "chunk-stream$RepresentationID$-$Number%05d$.m4s"}, 0, 0, E },
918 static const AVClass dash_class = {
919 .class_name = "dash muxer",
920 .item_name = av_default_item_name,
922 .version = LIBAVUTIL_VERSION_INT,
925 AVOutputFormat ff_dash_muxer = {
927 .long_name = NULL_IF_CONFIG_SMALL("DASH Muxer"),
928 .priv_data_size = sizeof(DASHContext),
929 .audio_codec = AV_CODEC_ID_AAC,
930 .video_codec = AV_CODEC_ID_H264,
931 .flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE,
932 .write_header = dash_write_header,
933 .write_packet = dash_write_packet,
934 .write_trailer = dash_write_trailer,
935 .codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
936 .priv_class = &dash_class,