diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c index 48e6f23c10..2110eb29ff 100644 --- a/libavformat/dashenc.c +++ b/libavformat/dashenc.c @@ -86,6 +86,7 @@ typedef struct AdaptationSet { AVDictionary *metadata; AVRational min_frame_rate, max_frame_rate; int ambiguous_frame_rate; + int64_t max_frag_duration; } AdaptationSet; typedef struct OutputStream { @@ -126,6 +127,7 @@ typedef struct OutputStream { int64_t total_pkt_duration; int muxer_overhead; int frag_type; + int64_t gop_size; } OutputStream; typedef struct DASHContext { @@ -171,11 +173,13 @@ typedef struct DASHContext { SegmentType segment_type_option; /* segment type as specified in options */ int ignore_io_errors; int lhls; + int ldash; int master_publish_rate; int nr_of_streams_to_flush; int nr_of_streams_flushed; int frag_type; int write_prft; + int64_t max_gop_size; } DASHContext; static struct codec_string { @@ -646,6 +650,10 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, AVFormatCont avio_printf(out, "availabilityTimeOffset=\"%.3f\" ", os->availability_time_offset); } + if (c->ldash && !final && os->frag_type != FRAG_TYPE_NONE && + (os->frag_type != FRAG_TYPE_DURATION || os->frag_duration != os->seg_duration)) + avio_printf(out, "availabilityTimeComplete=\"false\" "); + avio_printf(out, "initialization=\"%s\" media=\"%s\" startNumber=\"%d\"", os->init_seg_name, os->media_seg_name, c->use_timeline ? start_number : 1); if (c->presentation_time_offset) avio_printf(out, " presentationTimeOffset=\"%"PRId64"\"", c->presentation_time_offset); @@ -793,6 +801,8 @@ static int write_adaptation_set(AVFormatContext *s, AVIOContext *out, int as_ind avio_printf(out, " lang=\"%s\"", lang->value); avio_printf(out, ">\n"); + if (!final && c->ldash && as->max_frag_duration) + avio_printf(out, "\t\t\t\n", as->max_frag_duration); role = av_dict_get(as->metadata, "role", NULL, 0); if (role) avio_printf(out, "\t\t\t\n", role->value); @@ -828,6 +838,9 @@ static int write_adaptation_set(AVFormatContext *s, AVIOContext *out, int as_ind avio_printf(out, "\t\t\t\t\t\n", c->utc_timing_url); avio_printf(out, "\t\t\t\t\n"); } + if (!final && c->ldash && os->gop_size && os->frag_type != FRAG_TYPE_NONE && + (os->frag_type != FRAG_TYPE_DURATION || os->frag_duration != os->seg_duration)) + avio_printf(out, "\t\t\t\t\n", os->gop_size); output_segment_list(os, out, s, i, final); avio_printf(out, "\t\t\t\n"); } @@ -1076,7 +1089,8 @@ static int write_manifest(AVFormatContext *s, int final) if (c->use_template && !c->use_timeline) update_period = 500; avio_printf(out, "\tminimumUpdatePeriod=\"PT%"PRId64"S\"\n", update_period); - avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE); + if (!c->ldash) + avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE); if (c->availability_start_time[0]) avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time); format_date(now_str, sizeof(now_str), av_gettime()); @@ -1089,7 +1103,7 @@ static int write_manifest(AVFormatContext *s, int final) } } avio_printf(out, "\tminBufferTime=\""); - write_time(out, c->last_duration * 2); + write_time(out, c->ldash && c->max_gop_size ? c->max_gop_size : c->last_duration * 2); avio_printf(out, "\">\n"); avio_printf(out, "\t\n"); if (title) { @@ -1257,6 +1271,11 @@ static int dash_init(AVFormatContext *s) c->lhls = 0; } + if (c->ldash && !c->streaming) { + av_log(s, AV_LOG_WARNING, "LDash option will be ignored as streaming is not enabled\n"); + c->ldash = 0; + } + if (c->global_sidx && !c->single_file) { av_log(s, AV_LOG_WARNING, "Global SIDX option will be ignored as single_file is not enabled\n"); c->global_sidx = 0; @@ -1848,6 +1867,7 @@ static int dash_write_packet(AVFormatContext *s, AVPacket *pkt) DASHContext *c = s->priv_data; AVStream *st = s->streams[pkt->stream_index]; OutputStream *os = &c->streams[pkt->stream_index]; + AdaptationSet *as = &c->as[os->as_idx - 1]; int64_t seg_end_duration, elapsed_duration; int ret; @@ -1909,6 +1929,7 @@ static int dash_write_packet(AVFormatContext *s, AVPacket *pkt) os->availability_time_offset = ((double) os->seg_duration - frame_duration) / AV_TIME_BASE; + as->max_frag_duration = FFMAX(frame_duration, as->max_frag_duration); } if (c->use_template && !c->use_timeline) { @@ -1987,10 +2008,16 @@ static int dash_write_packet(AVFormatContext *s, AVPacket *pkt) AV_TIME_BASE_Q); os->availability_time_offset = ((double) os->seg_duration - frag_duration) / AV_TIME_BASE; + as->max_frag_duration = FFMAX(frag_duration, as->max_frag_duration); } } } + if (pkt->flags & AV_PKT_FLAG_KEY && (os->packets_written || os->nb_segments) && !os->gop_size) { + os->gop_size = os->last_duration + av_rescale_q(os->total_pkt_duration, st->time_base, AV_TIME_BASE_Q); + c->max_gop_size = FFMAX(c->max_gop_size, os->gop_size); + } + if ((ret = ff_write_chained(os->ctx, 0, pkt, s, 0)) < 0) return ret; @@ -2149,6 +2176,7 @@ static const AVOption options[] = { { "webm", "make segment file in WebM format", 0, AV_OPT_TYPE_CONST, {.i64 = SEGMENT_TYPE_WEBM }, 0, UINT_MAX, E, "segment_type"}, { "ignore_io_errors", "Ignore IO errors during open and write. Useful for long-duration runs with network output", OFFSET(ignore_io_errors), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E }, { "lhls", "Enable Low-latency HLS(Experimental). Adds #EXT-X-PREFETCH tag with current segment's URI", OFFSET(lhls), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E }, + { "ldash", "Enable Low-latency dash. Constrains the value of a few elements", OFFSET(ldash), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E }, { "master_m3u8_publish_rate", "Publish master playlist every after this many segment intervals", OFFSET(master_publish_rate), AV_OPT_TYPE_INT, {.i64 = 0}, 0, UINT_MAX, E}, { "write_prft", "Write producer reference time element", OFFSET(write_prft), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, E}, { NULL },