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_pts, start_pts, max_pts;
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 ffio_free_dyn_buf(&pb);
161 extradata_size = avio_close_dyn_buf(pb, &extradata);
165 if (extradata_size >= 4)
166 av_strlcatf(str, size, ".%02x%02x%02x",
167 extradata[1], extradata[2], extradata[3]);
172 static void dash_free(AVFormatContext *s)
174 DASHContext *c = s->priv_data;
178 for (i = 0; i < s->nb_streams; i++) {
179 OutputStream *os = &c->streams[i];
180 if (os->ctx && os->ctx_inited)
181 av_write_trailer(os->ctx);
182 if (os->ctx && os->ctx->pb)
183 av_free(os->ctx->pb);
184 ffurl_close(os->out);
187 avformat_free_context(os->ctx);
188 for (j = 0; j < os->nb_segments; j++)
189 av_free(os->segments[j]);
190 av_free(os->segments);
192 av_freep(&c->streams);
195 static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c)
197 int i, start_index = 0, start_number = 1;
198 if (c->window_size) {
199 start_index = FFMAX(os->nb_segments - c->window_size, 0);
200 start_number = FFMAX(os->segment_index - c->window_size, 1);
203 if (c->use_template) {
204 int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE;
205 avio_printf(out, "\t\t\t\t<SegmentTemplate timescale=\"%d\" ", timescale);
206 if (!c->use_timeline)
207 avio_printf(out, "duration=\"%"PRId64"\" ", c->last_duration);
208 avio_printf(out, "initialization=\"%s\" media=\"%s\" startNumber=\"%d\">\n", c->init_seg_name, c->media_seg_name, c->use_timeline ? start_number : 1);
209 if (c->use_timeline) {
210 int64_t cur_time = 0;
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 || seg->time != cur_time) {
217 cur_time = seg->time;
218 avio_printf(out, "t=\"%"PRId64"\" ", seg->time);
220 avio_printf(out, "d=\"%d\" ", seg->duration);
221 while (i + repeat + 1 < os->nb_segments &&
222 os->segments[i + repeat + 1]->duration == seg->duration &&
223 os->segments[i + repeat + 1]->time == os->segments[i + repeat]->time + os->segments[i + repeat]->duration)
226 avio_printf(out, "r=\"%d\" ", repeat);
227 avio_printf(out, "/>\n");
229 cur_time += (1 + repeat) * seg->duration;
231 avio_printf(out, "\t\t\t\t\t</SegmentTimeline>\n");
233 avio_printf(out, "\t\t\t\t</SegmentTemplate>\n");
234 } else if (c->single_file) {
235 avio_printf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", os->initfile);
236 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
237 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);
238 for (i = start_index; i < os->nb_segments; i++) {
239 Segment *seg = os->segments[i];
240 avio_printf(out, "\t\t\t\t\t<SegmentURL mediaRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->range_length - 1);
241 if (seg->index_length)
242 avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1);
243 avio_printf(out, "/>\n");
245 avio_printf(out, "\t\t\t\t</SegmentList>\n");
247 avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
248 avio_printf(out, "\t\t\t\t\t<Initialization sourceURL=\"%s\" />\n", os->initfile);
249 for (i = start_index; i < os->nb_segments; i++) {
250 Segment *seg = os->segments[i];
251 avio_printf(out, "\t\t\t\t\t<SegmentURL media=\"%s\" />\n", seg->file);
253 avio_printf(out, "\t\t\t\t</SegmentList>\n");
257 static DASHTmplId dash_read_tmpl_id(const char *identifier, char *format_tag,
258 size_t format_tag_size, const char **ptr) {
259 const char *next_ptr;
260 DASHTmplId id_type = DASH_TMPL_ID_UNDEFINED;
262 if (av_strstart(identifier, "$$", &next_ptr)) {
263 id_type = DASH_TMPL_ID_ESCAPE;
265 } else if (av_strstart(identifier, "$RepresentationID$", &next_ptr)) {
266 id_type = DASH_TMPL_ID_REP_ID;
267 // default to basic format, as $RepresentationID$ identifiers
268 // are not allowed to have custom format-tags.
269 av_strlcpy(format_tag, "%d", format_tag_size);
271 } else { // the following identifiers may have an explicit format_tag
272 if (av_strstart(identifier, "$Number", &next_ptr))
273 id_type = DASH_TMPL_ID_NUMBER;
274 else if (av_strstart(identifier, "$Bandwidth", &next_ptr))
275 id_type = DASH_TMPL_ID_BANDWIDTH;
276 else if (av_strstart(identifier, "$Time", &next_ptr))
277 id_type = DASH_TMPL_ID_TIME;
279 id_type = DASH_TMPL_ID_UNDEFINED;
281 // next parse the dash format-tag and generate a c-string format tag
282 // (next_ptr now points at the first '%' at the beginning of the format-tag)
283 if (id_type != DASH_TMPL_ID_UNDEFINED) {
284 const char *number_format = (id_type == DASH_TMPL_ID_TIME) ? PRId64 : "d";
285 if (next_ptr[0] == '$') { // no dash format-tag
286 snprintf(format_tag, format_tag_size, "%%%s", number_format);
289 const char *width_ptr;
290 // only tolerate single-digit width-field (i.e. up to 9-digit width)
291 if (av_strstart(next_ptr, "%0", &width_ptr) &&
292 av_isdigit(width_ptr[0]) &&
293 av_strstart(&width_ptr[1], "d$", &next_ptr)) {
294 // yes, we're using a format tag to build format_tag.
295 snprintf(format_tag, format_tag_size, "%s%c%s", "%0", width_ptr[0], number_format);
298 av_log(NULL, AV_LOG_WARNING, "Failed to parse format-tag beginning with %s. Expected either a "
299 "closing '$' character or a format-string like '%%0[width]d', "
300 "where width must be a single digit\n", next_ptr);
301 id_type = DASH_TMPL_ID_UNDEFINED;
309 static void dash_fill_tmpl_params(char *dst, size_t buffer_size,
310 const char *template, int rep_id,
311 int number, int bit_rate,
314 const char *t_cur = template;
315 while (dst_pos < buffer_size - 1 && *t_cur) {
316 char format_tag[7]; // May be "%d", "%0Xd", or "%0Xlld" (for $Time$), where X is in [0-9]
319 const char *t_next = strchr(t_cur, '$'); // copy over everything up to the first '$' character
321 int num_copy_bytes = FFMIN(t_next - t_cur, buffer_size - dst_pos - 1);
322 av_strlcpy(&dst[dst_pos], t_cur, num_copy_bytes + 1);
324 dst_pos += num_copy_bytes;
326 } else { // no more DASH identifiers to substitute - just copy the rest over and break
327 av_strlcpy(&dst[dst_pos], t_cur, buffer_size - dst_pos);
331 if (dst_pos >= buffer_size - 1 || !*t_cur)
334 // t_cur is now pointing to a '$' character
335 id_type = dash_read_tmpl_id(t_cur, format_tag, sizeof(format_tag), &t_next);
337 case DASH_TMPL_ID_ESCAPE:
338 av_strlcpy(&dst[dst_pos], "$", 2);
341 case DASH_TMPL_ID_REP_ID:
342 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, rep_id);
344 case DASH_TMPL_ID_NUMBER:
345 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, number);
347 case DASH_TMPL_ID_BANDWIDTH:
348 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, bit_rate);
350 case DASH_TMPL_ID_TIME:
351 n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, time);
353 case DASH_TMPL_ID_UNDEFINED:
354 // copy over one byte and advance
355 av_strlcpy(&dst[dst_pos], t_cur, 2);
360 // t_next points just past the processed identifier
361 // n is the number of bytes that were attempted to be written to dst
362 // (may have failed to write all because buffer_size).
365 dst_pos += FFMIN(n, buffer_size - dst_pos - 1);
370 static char *xmlescape(const char *str) {
371 int outlen = strlen(str)*3/2 + 6;
372 char *out = av_realloc(NULL, outlen + 1);
376 for (; *str; str++) {
377 if (pos + 6 > outlen) {
379 outlen = 2 * outlen + 6;
380 tmp = av_realloc(out, outlen + 1);
388 memcpy(&out[pos], "&", 5);
390 } else if (*str == '<') {
391 memcpy(&out[pos], "<", 4);
393 } else if (*str == '>') {
394 memcpy(&out[pos], ">", 4);
396 } else if (*str == '\'') {
397 memcpy(&out[pos], "'", 6);
399 } else if (*str == '\"') {
400 memcpy(&out[pos], """, 6);
410 static void write_time(AVIOContext *out, int64_t time)
412 int seconds = time / AV_TIME_BASE;
413 int fractions = time % AV_TIME_BASE;
414 int minutes = seconds / 60;
415 int hours = minutes / 60;
418 avio_printf(out, "PT");
420 avio_printf(out, "%dH", hours);
421 if (hours || minutes)
422 avio_printf(out, "%dM", minutes);
423 avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10));
426 static int write_manifest(AVFormatContext *s, int final)
428 DASHContext *c = s->priv_data;
430 char temp_filename[1024];
432 AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0);
434 snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename);
435 ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
437 av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
440 avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
441 avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
442 "\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n"
443 "\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
444 "\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n"
445 "\tprofiles=\"urn:mpeg:dash:profile:isoff-live:2011\"\n"
446 "\ttype=\"%s\"\n", final ? "static" : "dynamic");
448 avio_printf(out, "\tmediaPresentationDuration=\"");
449 write_time(out, c->total_duration);
450 avio_printf(out, "\"\n");
452 int64_t update_period = c->last_duration / AV_TIME_BASE;
453 if (c->use_template && !c->use_timeline)
455 avio_printf(out, "\tminimumUpdatePeriod=\"PT%"PRId64"S\"\n", update_period);
456 avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE);
457 if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) {
458 time_t t = time(NULL);
459 struct tm *ptm, tmbuf;
460 ptm = gmtime_r(&t, &tmbuf);
462 if (!strftime(c->availability_start_time, sizeof(c->availability_start_time),
463 "%Y-%m-%dT%H:%M:%S", ptm))
464 c->availability_start_time[0] = '\0';
467 if (c->availability_start_time[0])
468 avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time);
469 if (c->window_size && c->use_template) {
470 avio_printf(out, "\ttimeShiftBufferDepth=\"");
471 write_time(out, c->last_duration * c->window_size);
472 avio_printf(out, "\"\n");
475 avio_printf(out, "\tminBufferTime=\"");
476 write_time(out, c->last_duration);
477 avio_printf(out, "\">\n");
478 avio_printf(out, "\t<ProgramInformation>\n");
480 char *escaped = xmlescape(title->value);
481 avio_printf(out, "\t\t<Title>%s</Title>\n", escaped);
484 avio_printf(out, "\t</ProgramInformation>\n");
485 if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) {
486 OutputStream *os = &c->streams[0];
487 int start_index = FFMAX(os->nb_segments - c->window_size, 0);
488 int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q);
489 avio_printf(out, "\t<Period start=\"");
490 write_time(out, start_time);
491 avio_printf(out, "\">\n");
493 avio_printf(out, "\t<Period start=\"PT0.0S\">\n");
497 avio_printf(out, "\t\t<AdaptationSet id=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
498 for (i = 0; i < s->nb_streams; i++) {
499 AVStream *st = s->streams[i];
500 OutputStream *os = &c->streams[i];
501 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_VIDEO)
503 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);
504 output_segment_list(&c->streams[i], out, c);
505 avio_printf(out, "\t\t\t</Representation>\n");
507 avio_printf(out, "\t\t</AdaptationSet>\n");
510 avio_printf(out, "\t\t<AdaptationSet id=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
511 for (i = 0; i < s->nb_streams; i++) {
512 AVStream *st = s->streams[i];
513 OutputStream *os = &c->streams[i];
514 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
516 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);
517 avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", st->codec->channels);
518 output_segment_list(&c->streams[i], out, c);
519 avio_printf(out, "\t\t\t</Representation>\n");
521 avio_printf(out, "\t\t</AdaptationSet>\n");
523 avio_printf(out, "\t</Period>\n");
524 avio_printf(out, "</MPD>\n");
527 return ff_rename(temp_filename, s->filename, s);
530 static int dash_write_header(AVFormatContext *s)
532 DASHContext *c = s->priv_data;
534 AVOutputFormat *oformat;
538 if (c->single_file_name)
543 av_strlcpy(c->dirname, s->filename, sizeof(c->dirname));
544 ptr = strrchr(c->dirname, '/');
546 av_strlcpy(basename, &ptr[1], sizeof(basename));
549 c->dirname[0] = '\0';
550 av_strlcpy(basename, s->filename, sizeof(basename));
553 ptr = strrchr(basename, '.');
557 oformat = av_guess_format("mp4", NULL, NULL);
559 ret = AVERROR_MUXER_NOT_FOUND;
563 c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams);
565 ret = AVERROR(ENOMEM);
569 for (i = 0; i < s->nb_streams; i++) {
570 OutputStream *os = &c->streams[i];
571 AVFormatContext *ctx;
573 AVDictionary *opts = NULL;
576 os->bit_rate = s->streams[i]->codec->bit_rate ?
577 s->streams[i]->codec->bit_rate :
578 s->streams[i]->codec->rc_max_rate;
580 snprintf(os->bandwidth_str, sizeof(os->bandwidth_str),
581 " bandwidth=\"%d\"", os->bit_rate);
583 int level = s->strict_std_compliance >= FF_COMPLIANCE_STRICT ?
584 AV_LOG_ERROR : AV_LOG_WARNING;
585 av_log(s, level, "No bit rate set for stream %d\n", i);
586 if (s->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
587 ret = AVERROR(EINVAL);
592 ctx = avformat_alloc_context();
594 ret = AVERROR(ENOMEM);
598 ctx->oformat = oformat;
599 ctx->interrupt_callback = s->interrupt_callback;
601 if (!(st = avformat_new_stream(ctx, NULL))) {
602 ret = AVERROR(ENOMEM);
605 avcodec_copy_context(st->codec, s->streams[i]->codec);
606 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
607 st->time_base = s->streams[i]->time_base;
608 ctx->avoid_negative_ts = s->avoid_negative_ts;
610 ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL);
612 ret = AVERROR(ENOMEM);
616 if (c->single_file) {
617 if (c->single_file_name)
618 dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->single_file_name, i, 0, os->bit_rate, 0);
620 snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i);
622 dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->init_seg_name, i, 0, os->bit_rate, 0);
624 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
625 ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
628 os->init_start_pos = 0;
630 av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov", 0);
631 if ((ret = avformat_write_header(ctx, &opts)) < 0) {
638 av_log(s, AV_LOG_VERBOSE, "Representation %d init segment will be written to: %s\n", i, filename);
640 s->streams[i]->time_base = st->time_base;
641 // If the muxer wants to shift timestamps, request to have them shifted
642 // already before being handed to this muxer, so we don't have mismatches
643 // between the MPD and the actual segments.
644 s->avoid_negative_ts = ctx->avoid_negative_ts;
645 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
647 else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
650 set_codec_str(s, os->ctx->streams[0]->codec, os->codec_str, sizeof(os->codec_str));
651 os->first_pts = AV_NOPTS_VALUE;
652 os->max_pts = 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 if (seg->time < 0) // If pts<0, it is expected to be cut away with an edit list
693 seg->duration = duration;
694 seg->start_pos = start_pos;
695 seg->range_length = range_length;
696 seg->index_length = index_length;
697 os->segments[os->nb_segments++] = seg;
702 static void write_styp(AVIOContext *pb)
705 ffio_wfourcc(pb, "styp");
706 ffio_wfourcc(pb, "msdh");
707 avio_wb32(pb, 0); /* minor */
708 ffio_wfourcc(pb, "msdh");
709 ffio_wfourcc(pb, "msix");
712 static void find_index_range(AVFormatContext *s, const char *full_path,
713 int64_t pos, int *index_length)
719 ret = ffurl_open(&fd, full_path, AVIO_FLAG_READ, &s->interrupt_callback, NULL);
722 if (ffurl_seek(fd, pos, SEEK_SET) != pos) {
726 ret = ffurl_read(fd, buf, 8);
730 if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x'))
732 *index_length = AV_RB32(&buf[0]);
735 static int dash_flush(AVFormatContext *s, int final, int stream)
737 DASHContext *c = s->priv_data;
739 int cur_flush_segment_index = 0;
741 cur_flush_segment_index = c->streams[stream].segment_index;
743 for (i = 0; i < s->nb_streams; i++) {
744 OutputStream *os = &c->streams[i];
745 char filename[1024] = "", full_path[1024], temp_path[1024];
747 int range_length, index_length = 0;
749 if (!os->packets_written)
752 // Flush the single stream that got a keyframe right now.
753 // Flush all audio streams as well, in sync with video keyframes,
754 // but not the other video streams.
755 if (stream >= 0 && i != stream) {
756 if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
758 // Make sure we don't flush audio streams multiple times, when
759 // all video streams are flushed one at a time.
760 if (c->has_video && os->segment_index > cur_flush_segment_index)
764 if (!os->init_range_length) {
765 av_write_frame(os->ctx, NULL);
766 os->init_range_length = avio_tell(os->ctx->pb);
767 if (!c->single_file) {
768 ffurl_close(os->out);
773 start_pos = avio_tell(os->ctx->pb);
775 if (!c->single_file) {
776 dash_fill_tmpl_params(filename, sizeof(filename), c->media_seg_name, i, os->segment_index, os->bit_rate, os->start_pts);
777 snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename);
778 snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path);
779 ret = ffurl_open(&os->out, temp_path, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
782 write_styp(os->ctx->pb);
784 snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, os->initfile);
787 av_write_frame(os->ctx, NULL);
788 avio_flush(os->ctx->pb);
789 os->packets_written = 0;
791 range_length = avio_tell(os->ctx->pb) - start_pos;
792 if (c->single_file) {
793 find_index_range(s, full_path, start_pos, &index_length);
795 ffurl_close(os->out);
797 ret = ff_rename(temp_path, full_path, s);
801 add_segment(os, filename, os->start_pts, os->max_pts - os->start_pts, start_pos, range_length, index_length);
802 av_log(s, AV_LOG_VERBOSE, "Representation %d media segment %d written to: %s\n", i, os->segment_index, full_path);
805 if (c->window_size || (final && c->remove_at_exit)) {
806 for (i = 0; i < s->nb_streams; i++) {
807 OutputStream *os = &c->streams[i];
809 int remove = os->nb_segments - c->window_size - c->extra_window_size;
810 if (final && c->remove_at_exit)
811 remove = os->nb_segments;
813 for (j = 0; j < remove; j++) {
815 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file);
817 av_free(os->segments[j]);
819 os->nb_segments -= remove;
820 memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments));
826 ret = write_manifest(s, final);
830 static int dash_write_packet(AVFormatContext *s, AVPacket *pkt)
832 DASHContext *c = s->priv_data;
833 AVStream *st = s->streams[pkt->stream_index];
834 OutputStream *os = &c->streams[pkt->stream_index];
835 int64_t seg_end_duration = (os->segment_index) * (int64_t) c->min_seg_duration;
838 // If forcing the stream to start at 0, the mp4 muxer will set the start
839 // timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps.
840 if (os->first_pts == AV_NOPTS_VALUE &&
841 s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) {
842 pkt->pts -= pkt->dts;
846 if (os->first_pts == AV_NOPTS_VALUE)
847 os->first_pts = pkt->pts;
849 if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
850 pkt->flags & AV_PKT_FLAG_KEY && os->packets_written &&
851 av_compare_ts(pkt->pts - os->first_pts, st->time_base,
852 seg_end_duration, AV_TIME_BASE_Q) >= 0) {
853 int64_t prev_duration = c->last_duration;
855 c->last_duration = av_rescale_q(pkt->pts - os->start_pts,
858 c->total_duration = av_rescale_q(pkt->pts - os->first_pts,
862 if ((!c->use_timeline || !c->use_template) && prev_duration) {
863 if (c->last_duration < prev_duration*9/10 ||
864 c->last_duration > prev_duration*11/10) {
865 av_log(s, AV_LOG_WARNING,
866 "Segment durations differ too much, enable use_timeline "
867 "and use_template, or keep a stricter keyframe interval\n");
871 if ((ret = dash_flush(s, 0, pkt->stream_index)) < 0)
875 if (!os->packets_written) {
876 // If we wrote a previous segment, adjust the start time of the segment
877 // to the end of the previous one (which is the same as the mp4 muxer
878 // does). This avoids gaps in the timeline.
879 if (os->max_pts != AV_NOPTS_VALUE)
880 os->start_pts = os->max_pts;
882 os->start_pts = pkt->pts;
884 if (os->max_pts == AV_NOPTS_VALUE)
885 os->max_pts = pkt->pts + pkt->duration;
887 os->max_pts = FFMAX(os->max_pts, pkt->pts + pkt->duration);
888 os->packets_written++;
889 return ff_write_chained(os->ctx, 0, pkt, s, 0);
892 static int dash_write_trailer(AVFormatContext *s)
894 DASHContext *c = s->priv_data;
896 if (s->nb_streams > 0) {
897 OutputStream *os = &c->streams[0];
898 // If no segments have been written so far, try to do a crude
899 // guess of the segment duration
900 if (!c->last_duration)
901 c->last_duration = av_rescale_q(os->max_pts - os->start_pts,
902 s->streams[0]->time_base,
904 c->total_duration = av_rescale_q(os->max_pts - os->first_pts,
905 s->streams[0]->time_base,
908 dash_flush(s, 1, -1);
910 if (c->remove_at_exit) {
913 for (i = 0; i < s->nb_streams; i++) {
914 OutputStream *os = &c->streams[i];
915 snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
925 #define OFFSET(x) offsetof(DASHContext, x)
926 #define E AV_OPT_FLAG_ENCODING_PARAM
927 static const AVOption options[] = {
928 { "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
929 { "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 },
930 { "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E },
931 { "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
932 { "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
933 { "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
934 { "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
935 { "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 },
936 { "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 },
937 { "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 },
941 static const AVClass dash_class = {
942 .class_name = "dash muxer",
943 .item_name = av_default_item_name,
945 .version = LIBAVUTIL_VERSION_INT,
948 AVOutputFormat ff_dash_muxer = {
950 .long_name = NULL_IF_CONFIG_SMALL("DASH Muxer"),
951 .priv_data_size = sizeof(DASHContext),
952 .audio_codec = AV_CODEC_ID_AAC,
953 .video_codec = AV_CODEC_ID_H264,
954 .flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE,
955 .write_header = dash_write_header,
956 .write_packet = dash_write_packet,
957 .write_trailer = dash_write_trailer,
958 .codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
959 .priv_class = &dash_class,