Playback stops using live streaming from FFMPEG

[aletorrado]

Hi, I'm testing a few FFMPEG commands to stream to Shaka v2.0.0-beta. Some of them works OK with Shaka 1.5, but not with this version.

ffmpeg -i <live-stream> -f dash manifest.mpd
ffmpeg -i <live-stream> -f dash manifest.mpd
ffmpeg -i <live-stream> -x264opts 'keyint=25:scenecut=-1' -f dash manifest.mpd
ffmpeg -i <live-stream> -x264opts 'keyint=25:scenecut=-1' -f dash -use_template false manifest.mpd
Using any of these commands, playback suddenly stops after less than a minute usually. Shaka keeps fetching the manifest with the new chunks, but does not play anymore. Using Shaka 1.5 it seems OK.

ffmpeg -i <live-stream> -x264opts 'keyint=25:scenecut=-1' -f dash -use_timeline false manifest.mpd
Everything seems OK with this using any version of Shaka.

I would like to keep x264 scene detection, using flexible segment times with SegmentTemplate and SegmentTimeline, for maximum performance.

Notice that when the live streaming has ended, FFMPEG converts the manifest to type="static". Then any version of Shaka seems to play OK any of those commands. Problems happen only while in dynamic mode.

[tdrews]

Can you try from master with verbose logging enabled?

[aletorrado]

I cannot find where to enable verbose mode. Can you help me?

Examples on the debugging tutorial seems outdated:
shaka.log.setLevel(shaka.log.Level.DEBUG);

Thanks

[tdrews]

You can either call shaka.log.setLevel(shaka.log.Level.V2) from your application or you can add ?vv onto the end of your demo page, e.g., http://localhost/shaka/demo/?vv. Note that in both cases you need to be using the uncompiled library.

[tdrews]

Hi, any updates on this? Working / not working from master?

[aletorrado]

Let me test it. I'll come back here soon with that info.

[aletorrado]

It isn't working at all for me right now (even without using SegmentTimeline, as the example below). Using dash.js everything is OK. When I stop the broadcast, and switch the manifest from type=dynamic to type=static, shaka is able to play it.

Btw. all test were done streaming from localhost, to ensure no timing issues

This work:

<?xml version="1.0" encoding="utf-8"?>
<MPD xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="urn:mpeg:dash:schema:mpd:2011"
    xmlns:xlink="http://www.w3.org/1999/xlink"
    xsi:schemaLocation="urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd"
    profiles="urn:mpeg:dash:profile:isoff-live:2011"
    type="static"
    mediaPresentationDuration="PT2M25.7S"
    minBufferTime="PT5.0S">
    <ProgramInformation>
    </ProgramInformation>
    <Period start="PT0.0S">
        <AdaptationSet contentType="video" segmentAlignment="true" bitstreamSwitching="true" frameRate="30/1">
            <Representation id="0" mimeType="video/mp4" codecs="avc1.64001e" bandwidth="300000" width="640" height="360" frameRate="30/1">
                <SegmentTemplate timescale="1000000" duration="5000000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startNumber="1">
                </SegmentTemplate>
            </Representation>
        </AdaptationSet>
        <AdaptationSet contentType="audio" segmentAlignment="true" bitstreamSwitching="true">
            <Representation id="1" mimeType="audio/mp4" codecs="mp4a.40.2" bandwidth="96000" audioSamplingRate="44100">
                <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2" />
                <SegmentTemplate timescale="1000000" duration="5000000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startNumber="1">
                </SegmentTemplate>
            </Representation>
        </AdaptationSet>
    </Period>
</MPD>

This doesn't:

<?xml version="1.0" encoding="utf-8"?>
<MPD xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="urn:mpeg:dash:schema:mpd:2011"
    xmlns:xlink="http://www.w3.org/1999/xlink"
    xsi:schemaLocation="urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd"
    profiles="urn:mpeg:dash:profile:isoff-live:2011"
    type="dynamic"
    minimumUpdatePeriod="PT500S"
    suggestedPresentationDelay="PT5S"
    availabilityStartTime="2016-04-28T22:40:45"
    publishTime="2016-04-28T22:42:29"
    minBufferTime="PT5.0S">
    <ProgramInformation>
    </ProgramInformation>
    <Period start="PT0.0S">
        <AdaptationSet contentType="video" segmentAlignment="true" bitstreamSwitching="true" frameRate="30/1">
            <Representation id="0" mimeType="video/mp4" codecs="avc1.64001e" bandwidth="300000" width="640" height="360" frameRate="30/1">
                <SegmentTemplate timescale="1000000" duration="5000000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startNumber="1">
                </SegmentTemplate>
            </Representation>
        </AdaptationSet>
        <AdaptationSet contentType="audio" segmentAlignment="true" bitstreamSwitching="true">
            <Representation id="1" mimeType="audio/mp4" codecs="mp4a.40.2" bandwidth="96000" audioSamplingRate="44100">
                <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2" />
                <SegmentTemplate timescale="1000000" duration="5000000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startNumber="1">
                </SegmentTemplate>
            </Representation>
        </AdaptationSet>
    </Period>
</MPD>

Hope this helps.

[aletorrado]

This commit broke it all: 1108700

[tdrews]

With 294bcca you should be able to use
ffmpeg -i <live-stream> -f dash manifest.mpd
and
ffmpeg -i <live-stream> -x264opts 'keyint=25:scenecut=-1' -f dash manifest.mpd
in dynamic mode (Shaka should automatically switch to static mode after the final manifest update as well).

However, using -use_template false or -use_timeline false may not work in dynamic mode. This is because when using these options ffmpeg may vary the segment duration (i.e., it may vary SegmentList@duration and SegmentTemplate@duration) between manifest updates; this is rather unusual and likely not spec compliant (although when ffmpeg does this it outputs warnings indicating that SegmentTimeline should be used).

(Also, be sure to delete the old manifest before re-starting ffmpeg as ffmpeg doesn't overwrite the manifest right away.)