On 12/12/18 9:50 PM, Karthick J wrote: > Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks > are > trying to standardize a open LHLS spec. The draft spec is available in > https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md > This option will also try to comply with the above open spec, till Apple's > spec officially supports it. > Applicable only when @var{streaming} and @var{hls_playlist} options are > enabled. > --- > doc/muxers.texi | 8 ++++++++ > libavformat/dashenc.c | 37 +++++++++++++++++++++++++++++++++---- > 2 files changed, 41 insertions(+), 4 deletions(-) > > diff --git a/doc/muxers.texi b/doc/muxers.texi > index 809f88662e..4ed46a2220 100644 > --- a/doc/muxers.texi > +++ b/doc/muxers.texi > @@ -305,6 +305,14 @@ If this flag is set, the dash segment files will be in > in WebM format. > @item -ignore_io_errors @var{ignore_io_errors} > Ignore IO errors during open and write. Useful for long-duration runs with > network output. > > +@item -lhls @var{lhls} > +Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current > segment's URI. > +Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks > are > +trying to standardize a open LHLS spec. The draft spec is available in > https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md > +This option will also try to comply with the above open spec, till Apple's > spec officially supports it. > +Applicable only when @var{streaming} and @var{hls_playlist} options are > enabled. > +This is an experimental feature. > + > @end table > > @anchor{framecrc} > diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c > index f797b7bd1c..cfd0f601d4 100644 > --- a/libavformat/dashenc.c > +++ b/libavformat/dashenc.c > @@ -139,6 +139,7 @@ typedef struct DASHContext { > char *format_options_str; > SegmentType segment_type_option; /* segment type as specified in > options */ > int ignore_io_errors; > + int lhls; > } DASHContext; > > static struct codec_string { > @@ -418,7 +419,8 @@ static void get_start_index_number(OutputStream *os, > DASHContext *c, > } > > static void write_hls_media_playlist(OutputStream *os, AVFormatContext *s, > - int representation_id, int final) { > + int representation_id, int final, > + char *prefetch_url) { > DASHContext *c = s->priv_data; > int timescale = os->ctx->streams[0]->time_base.den; > char temp_filename_hls[1024]; > @@ -431,6 +433,11 @@ static void write_hls_media_playlist(OutputStream *os, > AVFormatContext *s, > int i, start_index, start_number; > > get_start_index_number(os, c, &start_index, &start_number); > + > + if (!c->hls_playlist || start_index >= os->nb_segments || > + os->segment_type != SEGMENT_TYPE_MP4) > + return; > + > get_hls_playlist_name(filename_hls, sizeof(filename_hls), > c->dirname, representation_id); > > @@ -468,6 +475,9 @@ static void write_hls_media_playlist(OutputStream *os, > AVFormatContext *s, > } > } > > + if (prefetch_url) > + avio_printf(c->m3u8_out, "#EXT-X-PREFETCH:%s\n", prefetch_url); > + > if (final) > ff_hls_write_end_list(c->m3u8_out); > > @@ -594,9 +604,8 @@ static void output_segment_list(OutputStream *os, > AVIOContext *out, AVFormatCont > } > avio_printf(out, "\t\t\t\t</SegmentList>\n"); > } > - if (c->hls_playlist && start_index < os->nb_segments && os->segment_type > == SEGMENT_TYPE_MP4) > - { > - write_hls_media_playlist(os, s, representation_id, final); > + if (!c->lhls || final) { > + write_hls_media_playlist(os, s, representation_id, final, NULL); > } > > } > @@ -1054,6 +1063,21 @@ static int dash_init(AVFormatContext *s) > c->seg_duration = c->min_seg_duration; > } > #endif > + if (c->lhls && s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) { > + av_log(s, AV_LOG_ERROR, > + "LHLS is experimental, Please set -strict experimental in > order to enable it.\n"); > + return AVERROR_EXPERIMENTAL; > + } > + > + if (c->lhls && !c->streaming) { > + av_log(s, AV_LOG_WARNING, "LHLS option will be ignored as streaming > is not enabled\n"); > + c->lhls = 0; > + } > + > + if (c->lhls && !c->hls_playlist) { > + av_log(s, AV_LOG_WARNING, "LHLS option will be ignored as > hls_playlist is not enabled\n"); > + c->lhls = 0; > + } > > av_strlcpy(c->dirname, s->url, sizeof(c->dirname)); > ptr = strrchr(c->dirname, '/'); > @@ -1635,6 +1659,10 @@ static int dash_write_packet(AVFormatContext *s, > AVPacket *pkt) > if (ret < 0) { > return handle_io_open_error(s, ret, os->temp_path); > } > + if (c->lhls) { > + char *prefetch_url = use_rename ? NULL : os->filename; > + write_hls_media_playlist(os, s, pkt->stream_index, 0, > prefetch_url); > + } > } > > //write out the data immediately in streaming mode > @@ -1760,6 +1788,7 @@ static const AVOption options[] = { > { "mp4", "make segment file in ISOBMFF format", 0, AV_OPT_TYPE_CONST, > {.i64 = SEGMENT_TYPE_MP4 }, 0, UINT_MAX, E, "segment_type"}, > { "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 }, > { NULL }, > }; >
Pushed Patchset. Regards, Karthick _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
