[gst-devel] Re: [gst-cvs] company gst-plugins: gst-plugins/ext/alsa/

Wim Taymans wim.taymans at chello.be
Sun Apr 13 05:26:04 CEST 2003

On Sun, 2003-04-13 at 06:13, Benjamin Otte wrote:
> CVS Root:       /cvsroot/gstreamer
> Module:         gst-plugins
> Changes by:     company
> Date:           Sat Apr 12 2003  21:13:25 PDT
> Log message:
> ALSA rewrite, part 5:
> - sync to timestamps (which breaks a _lot_, because most plugins send out wrong timestamps)
> - clocking support (A/V sync is superb as long as you don't sync and don't get wrong timestamps)
> - 1/2 of format conversion
> - assorted bugfixes
> I'd like to get people to check the timestamps the plugins send out.
> mpegdemux seems to be pretty broken, mad works (I just patched it...), avidemux works at least sometimes.
> Haven't checked more so far.

mpegdemux gets the timestamps out of the mpegstream (PTS), according to
the specs not every packet has a timestamp and if there are timestamps,
they are not guaranteed to be monotonically increasing (I/P/B frames).
It is the plugin's job to interpollate the timestamps (mad does(did?)
this, mpeg2dec does this too) when mpegdemux generates a packet with a
non-valid timestamp.

Also, filesrc ! alsasink should work correctly, even though there are no
valid timestamps on the buffers alsasink receives.


Wim Taymans <wim.taymans at chello.be>

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