[MPlayer-users] Late-starting audio streams

[Stephen Mollett]

Hi,

How should one handle media with audio streams which start some time
after the video stream starts?

I have a BD with an audio stream that begins about 7.5 seconds after the
video stream. (Actually, it has two audio streams, both of which start
late.) If I just play it normally, mplayer will say:

...
VIDEO H264(pid=4113) NO AUDIO! (try increasing -tsprobe) NO SUBS (yet)!
PROGRAM N. 1
...

and play the video stream without audio.

If I increase -tsprobe, as suggested, the audio stream is found but
begins playing immediately, so leads the video by about 7.5 seconds.
Setting -delay 7.5 to try and compensate causes all sorts of weirdness
to occur (video stops playing when audio starts, "Too many video
packets...", etc.)

Specifying -demuxer lavf finds the audio but, as with -tsprobe, it
begins playing immediately. Setting large values for -lavfdopts
analyzeduration and probesize gives an "inverse" effect - the audio
starts playing immediately then stops 7.5 seconds in when it should start!

Is there a known, "right"/"official" way to deal with this?

I've just tested the DVD version of the BluRay and it appears to also
have a late audio stream but the decoder is invoked correctly when the
stream begins (it initially says "No audio stream found" but then the
"Opening audio decoder" message is printed about 8 seconds after the
video starts playing).

I can give full mplayer -v output if anyone's interested. I could
probably also upload a sample although I'm not quite sure of the right
way to do this with a BluRay stream (would -dumpstream work?), and it'll
probably be big!

Thanks,
Stephen

[Ingo Brückl]

Post by Stephen Mollett
How should one handle media with audio streams which start some time
after the video stream starts?
If I increase -tsprobe, as suggested, the audio stream is found but
begins playing immediately, so leads the video by about 7.5 seconds.

Unfortunately, this is a know issue, see the thread starting with

http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2014-February/072307.html

Ingo

[Reimar Döffinger]

Post by Ingo Brückl

Post by Stephen Mollett
How should one handle media with audio streams which start some time
after the video stream starts?
If I increase -tsprobe, as suggested, the audio stream is found but
begins playing immediately, so leads the video by about 7.5 seconds.

Unfortunately, this is a know issue, see the thread starting with
http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2014-February/072307.html

That is not entirely correct.
It is a know and a bit difficult to fix issue with formats like MKV.
But it should work for DVD and BluRay really.
Specifically, when an audio stream is found later on, MPlayer
should switch to it and start playing.
This is kind of required for streaming uses to work properly
with these formats.
Thus a sample with -dumpstream of the first few seconds would be
a good idea indeed, assuming it's not just happening due to using
an old MPlayer version.

[Reimar Döffinger]

Post by Reimar Döffinger

Post by Ingo Brückl

Post by Stephen Mollett
How should one handle media with audio streams which start some time
after the video stream starts?
If I increase -tsprobe, as suggested, the audio stream is found but
begins playing immediately, so leads the video by about 7.5 seconds.

Unfortunately, this is a know issue, see the thread starting with
http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2014-February/072307.html

That is not entirely correct.
It is a know and a bit difficult to fix issue with formats like MKV.
But it should work for DVD and BluRay really.

And for these formats even late starting video streams should
now work properly!