[FFmpeg-devel] [PATCH 2/2] lavd/pulse_audio_enc: allow non monotonic streams

[Lukasz M]

On 2 January 2014 22:26, Michael Niedermayer <michaelni at gmx.at> wrote:

> On Tue, Dec 31, 2013 at 10:24:34PM +0100, Lukasz Marek wrote:
> > Signed-off-by: Lukasz Marek <lukasz.m.luki at gmail.com>
> > ---
> >  libavdevice/pulse_audio_enc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/libavdevice/pulse_audio_enc.c
> b/libavdevice/pulse_audio_enc.c
> > index e047299..1a416b5 100644
> > --- a/libavdevice/pulse_audio_enc.c
> > +++ b/libavdevice/pulse_audio_enc.c
> > @@ -179,6 +179,6 @@ AVOutputFormat ff_pulse_muxer = {
> >      .write_packet   = pulse_write_packet,
> >      .write_trailer  = pulse_write_trailer,
> >      .get_output_timestamp = pulse_get_output_timestamp,
> > -    .flags          = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
> > +    .flags          = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH | AVFMT_TS_ANY,
> >      .priv_class     = &pulse_muxer_class,
>
> this looks wrong
>
> the device would need a time machine to change the past sound that
> was potentially already played
>

This is for players, not tools like ffmpeg.
The scenario I have in mind is for example:

You write to device packets with pts: 0, 1, 2, 3, 4, 5... then you seek
back to 2 and play again 2, 3, 4, 5 etc...
So in fact you play again that was already played. The code in mux.c
changed in previous patch didn't allow that.
And if you don't write packets with real pts/dts (repeated values), but
keep increasing them then av_get_output_timestamp() will return useless
values.

If you still found it wrong then I would be glad to get some hint how to
solve this.