2 * Apple HTTP Live Streaming segmenter
3 * Copyright (c) 2012, Luca Barbato
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
29 #include "libavutil/avassert.h"
30 #include "libavutil/mathematics.h"
31 #include "libavutil/parseutils.h"
32 #include "libavutil/avstring.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/log.h"
38 #include "os_support.h"
40 typedef struct HLSSegment {
42 double duration; /* in seconds */
46 struct HLSSegment *next;
49 typedef enum HLSFlags {
50 // Generate a single media file and use byte ranges in the playlist.
51 HLS_SINGLE_FILE = (1 << 0),
52 HLS_DELETE_SEGMENTS = (1 << 1),
55 typedef struct HLSContext {
56 const AVClass *class; // Class for private options.
59 int64_t start_sequence;
60 AVOutputFormat *oformat;
64 float time; // Set by a private option.
65 int max_nb_segments; // Set by a private option.
66 int wrap; // Set by a private option.
67 uint32_t flags; // enum HLSFlags
68 char *segment_filename;
71 int64_t recording_time;
75 double duration; // last segment duration computed so far, in seconds
76 int64_t start_pos; // last segment starting position
77 int64_t size; // last segment size
81 HLSSegment *last_segment;
82 HLSSegment *old_segments;
86 char *format_options_str;
87 AVDictionary *format_options;
92 static int hls_delete_old_segments(HLSContext *hls) {
94 HLSSegment *segment, *previous_segment = NULL;
95 float playlist_duration = 0.0f;
96 int ret = 0, path_size;
97 char *dirname = NULL, *p, *path;
99 segment = hls->segments;
101 playlist_duration += segment->duration;
102 segment = segment->next;
105 segment = hls->old_segments;
107 playlist_duration -= segment->duration;
108 previous_segment = segment;
109 segment = previous_segment->next;
110 if (playlist_duration <= -previous_segment->duration) {
111 previous_segment->next = NULL;
117 if (hls->segment_filename) {
118 dirname = av_strdup(hls->segment_filename);
120 dirname = av_strdup(hls->avf->filename);
123 ret = AVERROR(ENOMEM);
126 p = (char *)av_basename(dirname);
131 av_log(hls, AV_LOG_DEBUG, "deleting old segment %s\n",
133 path_size = strlen(dirname) + strlen(segment->filename) + 1;
134 path = av_malloc(path_size);
136 ret = AVERROR(ENOMEM);
139 av_strlcpy(path, dirname, path_size);
140 av_strlcat(path, segment->filename, path_size);
141 if (unlink(path) < 0) {
142 av_log(hls, AV_LOG_ERROR, "failed to delete old segment %s: %s\n",
143 path, strerror(errno));
146 previous_segment = segment;
147 segment = previous_segment->next;
148 av_free(previous_segment);
157 static int hls_mux_init(AVFormatContext *s)
159 HLSContext *hls = s->priv_data;
163 ret = avformat_alloc_output_context2(&hls->avf, hls->oformat, NULL, NULL);
168 oc->oformat = hls->oformat;
169 oc->interrupt_callback = s->interrupt_callback;
170 oc->max_delay = s->max_delay;
171 av_dict_copy(&oc->metadata, s->metadata, 0);
173 for (i = 0; i < s->nb_streams; i++) {
175 if (!(st = avformat_new_stream(oc, NULL)))
176 return AVERROR(ENOMEM);
177 avcodec_copy_context(st->codec, s->streams[i]->codec);
178 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
179 st->time_base = s->streams[i]->time_base;
186 /* Create a new segment and append it to the segment list */
187 static int hls_append_segment(HLSContext *hls, double duration, int64_t pos,
190 HLSSegment *en = av_malloc(sizeof(*en));
194 return AVERROR(ENOMEM);
196 av_strlcpy(en->filename, av_basename(hls->avf->filename), sizeof(en->filename));
198 en->duration = duration;
206 hls->last_segment->next = en;
208 hls->last_segment = en;
210 if (hls->max_nb_segments && hls->nb_entries >= hls->max_nb_segments) {
212 hls->segments = en->next;
213 if (en && hls->flags & HLS_DELETE_SEGMENTS &&
214 !(hls->flags & HLS_SINGLE_FILE || hls->wrap)) {
215 en->next = hls->old_segments;
216 hls->old_segments = en;
217 if ((ret = hls_delete_old_segments(hls)) < 0)
229 static void hls_free_segments(HLSSegment *p)
240 static int hls_window(AVFormatContext *s, int last)
242 HLSContext *hls = s->priv_data;
244 int target_duration = 0;
246 int64_t sequence = FFMAX(hls->start_sequence, hls->sequence - hls->nb_entries);
247 int version = hls->flags & HLS_SINGLE_FILE ? 4 : 3;
249 if ((ret = avio_open2(&hls->pb, s->filename, AVIO_FLAG_WRITE,
250 &s->interrupt_callback, NULL)) < 0)
253 for (en = hls->segments; en; en = en->next) {
254 if (target_duration < en->duration)
255 target_duration = ceil(en->duration);
258 avio_printf(hls->pb, "#EXTM3U\n");
259 avio_printf(hls->pb, "#EXT-X-VERSION:%d\n", version);
260 if (hls->allowcache == 0 || hls->allowcache == 1) {
261 avio_printf(hls->pb, "#EXT-X-ALLOW-CACHE:%s\n", hls->allowcache == 0 ? "NO" : "YES");
263 avio_printf(hls->pb, "#EXT-X-TARGETDURATION:%d\n", target_duration);
264 avio_printf(hls->pb, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);
266 av_log(s, AV_LOG_VERBOSE, "EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",
269 for (en = hls->segments; en; en = en->next) {
270 avio_printf(hls->pb, "#EXTINF:%f,\n", en->duration);
271 if (hls->flags & HLS_SINGLE_FILE)
272 avio_printf(hls->pb, "#EXT-X-BYTERANGE:%"PRIi64"@%"PRIi64"\n",
275 avio_printf(hls->pb, "%s", hls->baseurl);
276 avio_printf(hls->pb, "%s\n", en->filename);
280 avio_printf(hls->pb, "#EXT-X-ENDLIST\n");
283 avio_closep(&hls->pb);
287 static int hls_start(AVFormatContext *s)
289 HLSContext *c = s->priv_data;
290 AVFormatContext *oc = c->avf;
293 if (c->flags & HLS_SINGLE_FILE)
294 av_strlcpy(oc->filename, c->basename,
295 sizeof(oc->filename));
297 if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
298 c->basename, c->wrap ? c->sequence % c->wrap : c->sequence) < 0) {
299 av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);
300 return AVERROR(EINVAL);
304 if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
305 &s->interrupt_callback, NULL)) < 0)
308 if (oc->oformat->priv_class && oc->priv_data)
309 av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);
314 static int hls_write_header(AVFormatContext *s)
316 HLSContext *hls = s->priv_data;
319 const char *pattern = "%d.ts";
320 AVDictionary *options = NULL;
323 hls->sequence = hls->start_sequence;
324 hls->recording_time = hls->time * AV_TIME_BASE;
325 hls->start_pts = AV_NOPTS_VALUE;
327 if (hls->format_options_str) {
328 ret = av_dict_parse_string(&hls->format_options, hls->format_options_str, "=", ":", 0);
330 av_log(s, AV_LOG_ERROR, "Could not parse format options list '%s'\n", hls->format_options_str);
335 for (i = 0; i < s->nb_streams; i++)
337 s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;
339 if (hls->has_video > 1)
340 av_log(s, AV_LOG_WARNING,
341 "More than a single video stream present, "
342 "expect issues decoding it.\n");
344 hls->oformat = av_guess_format("mpegts", NULL, NULL);
347 ret = AVERROR_MUXER_NOT_FOUND;
351 if (hls->segment_filename) {
352 hls->basename = av_strdup(hls->segment_filename);
353 if (!hls->basename) {
354 ret = AVERROR(ENOMEM);
358 if (hls->flags & HLS_SINGLE_FILE)
361 basename_size = strlen(s->filename) + strlen(pattern) + 1;
362 hls->basename = av_malloc(basename_size);
363 if (!hls->basename) {
364 ret = AVERROR(ENOMEM);
368 av_strlcpy(hls->basename, s->filename, basename_size);
370 p = strrchr(hls->basename, '.');
373 av_strlcat(hls->basename, pattern, basename_size);
376 if ((ret = hls_mux_init(s)) < 0)
379 if ((ret = hls_start(s)) < 0)
382 av_dict_copy(&options, hls->format_options, 0);
383 ret = avformat_write_header(hls->avf, &options);
384 if (av_dict_count(options)) {
385 av_log(s, AV_LOG_ERROR, "Some of provided format options in '%s' are not recognized\n", hls->format_options_str);
386 ret = AVERROR(EINVAL);
389 av_assert0(s->nb_streams == hls->avf->nb_streams);
390 for (i = 0; i < s->nb_streams; i++) {
391 AVStream *inner_st = hls->avf->streams[i];
392 AVStream *outer_st = s->streams[i];
393 avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits, inner_st->time_base.num, inner_st->time_base.den);
397 av_dict_free(&options);
399 av_freep(&hls->basename);
401 avformat_free_context(hls->avf);
406 static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
408 HLSContext *hls = s->priv_data;
409 AVFormatContext *oc = hls->avf;
410 AVStream *st = s->streams[pkt->stream_index];
411 int64_t end_pts = hls->recording_time * hls->number;
413 int ret, can_split = 1;
415 if (hls->start_pts == AV_NOPTS_VALUE) {
416 hls->start_pts = pkt->pts;
417 hls->end_pts = pkt->pts;
420 if (hls->has_video) {
421 can_split = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
422 pkt->flags & AV_PKT_FLAG_KEY;
423 is_ref_pkt = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;
425 if (pkt->pts == AV_NOPTS_VALUE)
426 is_ref_pkt = can_split = 0;
429 hls->duration = (double)(pkt->pts - hls->end_pts)
430 * st->time_base.num / st->time_base.den;
432 if (can_split && av_compare_ts(pkt->pts - hls->start_pts, st->time_base,
433 end_pts, AV_TIME_BASE_Q) >= 0) {
434 int64_t new_start_pos;
435 av_write_frame(oc, NULL); /* Flush any buffered data */
437 new_start_pos = avio_tell(hls->avf->pb);
438 hls->size = new_start_pos - hls->start_pos;
439 ret = hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
440 hls->start_pos = new_start_pos;
444 hls->end_pts = pkt->pts;
447 if (hls->flags & HLS_SINGLE_FILE) {
448 if (hls->avf->oformat->priv_class && hls->avf->priv_data)
449 av_opt_set(hls->avf->priv_data, "mpegts_flags", "resend_headers", 0);
452 avio_closep(&oc->pb);
462 if ((ret = hls_window(s, 0)) < 0)
466 ret = ff_write_chained(oc, pkt->stream_index, pkt, s, 0);
471 static int hls_write_trailer(struct AVFormatContext *s)
473 HLSContext *hls = s->priv_data;
474 AVFormatContext *oc = hls->avf;
476 av_write_trailer(oc);
478 hls->size = avio_tell(hls->avf->pb) - hls->start_pos;
479 avio_closep(&oc->pb);
480 hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
482 av_freep(&hls->basename);
483 avformat_free_context(oc);
487 hls_free_segments(hls->segments);
488 hls_free_segments(hls->old_segments);
493 #define OFFSET(x) offsetof(HLSContext, x)
494 #define E AV_OPT_FLAG_ENCODING_PARAM
495 static const AVOption options[] = {
496 {"start_number", "set first number in the sequence", OFFSET(start_sequence),AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, E},
497 {"hls_time", "set segment length in seconds", OFFSET(time), AV_OPT_TYPE_FLOAT, {.dbl = 2}, 0, FLT_MAX, E},
498 {"hls_list_size", "set maximum number of playlist entries", OFFSET(max_nb_segments), AV_OPT_TYPE_INT, {.i64 = 5}, 0, INT_MAX, E},
499 {"hls_ts_options","set hls mpegts list of options for the container format used for hls", OFFSET(format_options_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
500 {"hls_wrap", "set number after which the index wraps", OFFSET(wrap), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, E},
501 {"hls_allow_cache", "explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments", OFFSET(allowcache), AV_OPT_TYPE_INT, {.i64 = -1}, INT_MIN, INT_MAX, E},
502 {"hls_base_url", "url to prepend to each playlist entry", OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
503 {"hls_segment_filename", "filename template for segment files", OFFSET(segment_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
504 {"hls_flags", "set flags affecting HLS playlist and media file generation", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0 }, 0, UINT_MAX, E, "flags"},
505 {"single_file", "generate a single media file indexed with byte ranges", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SINGLE_FILE }, 0, UINT_MAX, E, "flags"},
506 {"delete_segments", "delete segment files that are no longer part of the playlist", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DELETE_SEGMENTS }, 0, UINT_MAX, E, "flags"},
511 static const AVClass hls_class = {
512 .class_name = "hls muxer",
513 .item_name = av_default_item_name,
515 .version = LIBAVUTIL_VERSION_INT,
519 AVOutputFormat ff_hls_muxer = {
521 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
522 .extensions = "m3u8",
523 .priv_data_size = sizeof(HLSContext),
524 .audio_codec = AV_CODEC_ID_AAC,
525 .video_codec = AV_CODEC_ID_H264,
526 .flags = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
527 .write_header = hls_write_header,
528 .write_packet = hls_write_packet,
529 .write_trailer = hls_write_trailer,
530 .priv_class = &hls_class,