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),
53 HLS_ROUND_DURATIONS = (1 << 2),
54 HLS_DISCONT_START = (1 << 3),
55 HLS_OMIT_ENDLIST = (1 << 4),
58 typedef struct HLSContext {
59 const AVClass *class; // Class for private options.
62 int64_t start_sequence;
63 AVOutputFormat *oformat;
67 float time; // Set by a private option.
68 int max_nb_segments; // Set by a private option.
69 int wrap; // Set by a private option.
70 uint32_t flags; // enum HLSFlags
71 char *segment_filename;
74 int64_t recording_time;
78 double duration; // last segment duration computed so far, in seconds
79 int64_t start_pos; // last segment starting position
80 int64_t size; // last segment size
82 int discontinuity_set;
85 HLSSegment *last_segment;
86 HLSSegment *old_segments;
90 char *format_options_str;
91 AVDictionary *format_options;
94 static int hls_delete_old_segments(HLSContext *hls) {
96 HLSSegment *segment, *previous_segment = NULL;
97 float playlist_duration = 0.0f;
98 int ret = 0, path_size;
99 char *dirname = NULL, *p, *path;
101 segment = hls->segments;
103 playlist_duration += segment->duration;
104 segment = segment->next;
107 segment = hls->old_segments;
109 playlist_duration -= segment->duration;
110 previous_segment = segment;
111 segment = previous_segment->next;
112 if (playlist_duration <= -previous_segment->duration) {
113 previous_segment->next = NULL;
119 if (hls->segment_filename) {
120 dirname = av_strdup(hls->segment_filename);
122 dirname = av_strdup(hls->avf->filename);
125 ret = AVERROR(ENOMEM);
128 p = (char *)av_basename(dirname);
133 av_log(hls, AV_LOG_DEBUG, "deleting old segment %s\n",
135 path_size = strlen(dirname) + strlen(segment->filename) + 1;
136 path = av_malloc(path_size);
138 ret = AVERROR(ENOMEM);
141 av_strlcpy(path, dirname, path_size);
142 av_strlcat(path, segment->filename, path_size);
143 if (unlink(path) < 0) {
144 av_log(hls, AV_LOG_ERROR, "failed to delete old segment %s: %s\n",
145 path, strerror(errno));
148 previous_segment = segment;
149 segment = previous_segment->next;
150 av_free(previous_segment);
159 static int hls_mux_init(AVFormatContext *s)
161 HLSContext *hls = s->priv_data;
165 ret = avformat_alloc_output_context2(&hls->avf, hls->oformat, NULL, NULL);
170 oc->oformat = hls->oformat;
171 oc->interrupt_callback = s->interrupt_callback;
172 oc->max_delay = s->max_delay;
173 av_dict_copy(&oc->metadata, s->metadata, 0);
175 for (i = 0; i < s->nb_streams; i++) {
177 if (!(st = avformat_new_stream(oc, NULL)))
178 return AVERROR(ENOMEM);
179 avcodec_copy_context(st->codec, s->streams[i]->codec);
180 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
181 st->time_base = s->streams[i]->time_base;
188 /* Create a new segment and append it to the segment list */
189 static int hls_append_segment(HLSContext *hls, double duration, int64_t pos,
192 HLSSegment *en = av_malloc(sizeof(*en));
196 return AVERROR(ENOMEM);
198 av_strlcpy(en->filename, av_basename(hls->avf->filename), sizeof(en->filename));
200 en->duration = duration;
208 hls->last_segment->next = en;
210 hls->last_segment = en;
212 if (hls->max_nb_segments && hls->nb_entries >= hls->max_nb_segments) {
214 hls->segments = en->next;
215 if (en && hls->flags & HLS_DELETE_SEGMENTS &&
216 !(hls->flags & HLS_SINGLE_FILE || hls->wrap)) {
217 en->next = hls->old_segments;
218 hls->old_segments = en;
219 if ((ret = hls_delete_old_segments(hls)) < 0)
231 static void hls_free_segments(HLSSegment *p)
242 static int hls_window(AVFormatContext *s, int last)
244 HLSContext *hls = s->priv_data;
246 int target_duration = 0;
248 AVIOContext *out = NULL;
249 char temp_filename[1024];
250 int64_t sequence = FFMAX(hls->start_sequence, hls->sequence - hls->nb_entries);
251 int version = hls->flags & HLS_SINGLE_FILE ? 4 : 3;
252 const char *proto = avio_find_protocol_name(s->filename);
253 int use_rename = proto && !strcmp(proto, "file");
254 static unsigned warned_non_file;
256 if (!use_rename && !warned_non_file++)
257 av_log(s, AV_LOG_ERROR, "Cannot use rename on non file protocol, this may lead to races and temporarly partial files\n");
259 snprintf(temp_filename, sizeof(temp_filename), use_rename ? "%s.tmp" : "%s", s->filename);
260 if ((ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE,
261 &s->interrupt_callback, NULL)) < 0)
264 for (en = hls->segments; en; en = en->next) {
265 if (target_duration < en->duration)
266 target_duration = ceil(en->duration);
269 hls->discontinuity_set = 0;
270 avio_printf(out, "#EXTM3U\n");
271 avio_printf(out, "#EXT-X-VERSION:%d\n", version);
272 if (hls->allowcache == 0 || hls->allowcache == 1) {
273 avio_printf(out, "#EXT-X-ALLOW-CACHE:%s\n", hls->allowcache == 0 ? "NO" : "YES");
275 avio_printf(out, "#EXT-X-TARGETDURATION:%d\n", target_duration);
276 avio_printf(out, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);
278 av_log(s, AV_LOG_VERBOSE, "EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",
280 if((hls->flags & HLS_DISCONT_START) && sequence==hls->start_sequence && hls->discontinuity_set==0 ){
281 avio_printf(out, "#EXT-X-DISCONTINUITY\n");
282 hls->discontinuity_set = 1;
284 for (en = hls->segments; en; en = en->next) {
285 if (hls->flags & HLS_ROUND_DURATIONS)
286 avio_printf(out, "#EXTINF:%d,\n", (int)round(en->duration));
288 avio_printf(out, "#EXTINF:%f,\n", en->duration);
289 if (hls->flags & HLS_SINGLE_FILE)
290 avio_printf(out, "#EXT-X-BYTERANGE:%"PRIi64"@%"PRIi64"\n",
293 avio_printf(out, "%s", hls->baseurl);
294 avio_printf(out, "%s\n", en->filename);
297 if (last && (hls->flags & HLS_OMIT_ENDLIST)==0)
298 avio_printf(out, "#EXT-X-ENDLIST\n");
302 if (ret >= 0 && use_rename)
303 ff_rename(temp_filename, s->filename, s);
307 static int hls_start(AVFormatContext *s)
309 HLSContext *c = s->priv_data;
310 AVFormatContext *oc = c->avf;
313 if (c->flags & HLS_SINGLE_FILE)
314 av_strlcpy(oc->filename, c->basename,
315 sizeof(oc->filename));
317 if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
318 c->basename, c->wrap ? c->sequence % c->wrap : c->sequence) < 0) {
319 av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);
320 return AVERROR(EINVAL);
324 if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
325 &s->interrupt_callback, NULL)) < 0)
328 if (oc->oformat->priv_class && oc->priv_data)
329 av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);
334 static int hls_write_header(AVFormatContext *s)
336 HLSContext *hls = s->priv_data;
339 const char *pattern = "%d.ts";
340 AVDictionary *options = NULL;
343 hls->sequence = hls->start_sequence;
344 hls->recording_time = hls->time * AV_TIME_BASE;
345 hls->start_pts = AV_NOPTS_VALUE;
347 if (hls->format_options_str) {
348 ret = av_dict_parse_string(&hls->format_options, hls->format_options_str, "=", ":", 0);
350 av_log(s, AV_LOG_ERROR, "Could not parse format options list '%s'\n", hls->format_options_str);
355 for (i = 0; i < s->nb_streams; i++)
357 s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;
359 if (hls->has_video > 1)
360 av_log(s, AV_LOG_WARNING,
361 "More than a single video stream present, "
362 "expect issues decoding it.\n");
364 hls->oformat = av_guess_format("mpegts", NULL, NULL);
367 ret = AVERROR_MUXER_NOT_FOUND;
371 if (hls->segment_filename) {
372 hls->basename = av_strdup(hls->segment_filename);
373 if (!hls->basename) {
374 ret = AVERROR(ENOMEM);
378 if (hls->flags & HLS_SINGLE_FILE)
381 basename_size = strlen(s->filename) + strlen(pattern) + 1;
382 hls->basename = av_malloc(basename_size);
383 if (!hls->basename) {
384 ret = AVERROR(ENOMEM);
388 av_strlcpy(hls->basename, s->filename, basename_size);
390 p = strrchr(hls->basename, '.');
393 av_strlcat(hls->basename, pattern, basename_size);
396 if ((ret = hls_mux_init(s)) < 0)
399 if ((ret = hls_start(s)) < 0)
402 av_dict_copy(&options, hls->format_options, 0);
403 ret = avformat_write_header(hls->avf, &options);
404 if (av_dict_count(options)) {
405 av_log(s, AV_LOG_ERROR, "Some of provided format options in '%s' are not recognized\n", hls->format_options_str);
406 ret = AVERROR(EINVAL);
409 av_assert0(s->nb_streams == hls->avf->nb_streams);
410 for (i = 0; i < s->nb_streams; i++) {
411 AVStream *inner_st = hls->avf->streams[i];
412 AVStream *outer_st = s->streams[i];
413 avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits, inner_st->time_base.num, inner_st->time_base.den);
417 av_dict_free(&options);
419 av_freep(&hls->basename);
421 avformat_free_context(hls->avf);
426 static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
428 HLSContext *hls = s->priv_data;
429 AVFormatContext *oc = hls->avf;
430 AVStream *st = s->streams[pkt->stream_index];
431 int64_t end_pts = hls->recording_time * hls->number;
433 int ret, can_split = 1;
435 if (hls->start_pts == AV_NOPTS_VALUE) {
436 hls->start_pts = pkt->pts;
437 hls->end_pts = pkt->pts;
440 if (hls->has_video) {
441 can_split = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
442 pkt->flags & AV_PKT_FLAG_KEY;
443 is_ref_pkt = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;
445 if (pkt->pts == AV_NOPTS_VALUE)
446 is_ref_pkt = can_split = 0;
449 hls->duration = (double)(pkt->pts - hls->end_pts)
450 * st->time_base.num / st->time_base.den;
452 if (can_split && av_compare_ts(pkt->pts - hls->start_pts, st->time_base,
453 end_pts, AV_TIME_BASE_Q) >= 0) {
454 int64_t new_start_pos;
455 av_write_frame(oc, NULL); /* Flush any buffered data */
457 new_start_pos = avio_tell(hls->avf->pb);
458 hls->size = new_start_pos - hls->start_pos;
459 ret = hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
460 hls->start_pos = new_start_pos;
464 hls->end_pts = pkt->pts;
467 if (hls->flags & HLS_SINGLE_FILE) {
468 if (hls->avf->oformat->priv_class && hls->avf->priv_data)
469 av_opt_set(hls->avf->priv_data, "mpegts_flags", "resend_headers", 0);
472 avio_closep(&oc->pb);
482 if ((ret = hls_window(s, 0)) < 0)
486 ret = ff_write_chained(oc, pkt->stream_index, pkt, s, 0);
491 static int hls_write_trailer(struct AVFormatContext *s)
493 HLSContext *hls = s->priv_data;
494 AVFormatContext *oc = hls->avf;
496 av_write_trailer(oc);
498 hls->size = avio_tell(hls->avf->pb) - hls->start_pos;
499 avio_closep(&oc->pb);
500 hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
502 av_freep(&hls->basename);
503 avformat_free_context(oc);
507 hls_free_segments(hls->segments);
508 hls_free_segments(hls->old_segments);
512 #define OFFSET(x) offsetof(HLSContext, x)
513 #define E AV_OPT_FLAG_ENCODING_PARAM
514 static const AVOption options[] = {
515 {"start_number", "set first number in the sequence", OFFSET(start_sequence),AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, E},
516 {"hls_time", "set segment length in seconds", OFFSET(time), AV_OPT_TYPE_FLOAT, {.dbl = 2}, 0, FLT_MAX, E},
517 {"hls_list_size", "set maximum number of playlist entries", OFFSET(max_nb_segments), AV_OPT_TYPE_INT, {.i64 = 5}, 0, INT_MAX, E},
518 {"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},
519 {"hls_wrap", "set number after which the index wraps", OFFSET(wrap), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, E},
520 {"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},
521 {"hls_base_url", "url to prepend to each playlist entry", OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
522 {"hls_segment_filename", "filename template for segment files", OFFSET(segment_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
523 {"hls_flags", "set flags affecting HLS playlist and media file generation", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0 }, 0, UINT_MAX, E, "flags"},
524 {"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"},
525 {"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"},
526 {"round_durations", "round durations in m3u8 to whole numbers", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_ROUND_DURATIONS }, 0, UINT_MAX, E, "flags"},
527 {"discont_start", "start the playlist with a discontinuity tag", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DISCONT_START }, 0, UINT_MAX, E, "flags"},
528 {"omit_endlist", "Do not append an endlist when ending stream", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_OMIT_ENDLIST }, 0, UINT_MAX, E, "flags"},
533 static const AVClass hls_class = {
534 .class_name = "hls muxer",
535 .item_name = av_default_item_name,
537 .version = LIBAVUTIL_VERSION_INT,
541 AVOutputFormat ff_hls_muxer = {
543 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
544 .extensions = "m3u8",
545 .priv_data_size = sizeof(HLSContext),
546 .audio_codec = AV_CODEC_ID_AAC,
547 .video_codec = AV_CODEC_ID_H264,
548 .flags = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
549 .write_header = hls_write_header,
550 .write_packet = hls_write_packet,
551 .write_trailer = hls_write_trailer,
552 .priv_class = &hls_class,