[FFmpeg-devel] [PATCH] libavdevice: JACK demuxer

Luca Abeni lucabe72
Fri Feb 27 21:33:18 CET 2009

Olivier Guilyardi wrote:
> Luca Abeni wrote:
>> Hi,
>> I do not comment on the rest of the patch (yet :), but:
>> Reimar D?ffinger wrote:
>> [...]
>>>> +            info.pts = av_gettime() - (latency + cycle_delay) * self->frame_ms;
>>> The system time should not be stored anywhere without explicit
>>> permission from the user, particularly not as an absolute value.
>> This is needed for synchronising the audio with video or other media 
>> coming from other devices. If it really is a security issue (but in this
>> case I do not believe it is) maybe the usual "round the time to ms" can 
>> be a solution?
> I have a simple question here: must the pts be absolute (number of seconds since
>  the epoch) or can it be relative (for example 0 for the first audio sample).
> Luca you already told me it must be absolute, but I still have doubts about this.

If it is relative to the first audio sample, how do you synchronise with 
a different stream (that does not know when this stream's first audio 
sample is)?


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