Re: IO streams sync

[James Courtier-Dutton <James@superbug.co.uk>]

alejandro wrote:
>>
> 
> Lee and James,
> 
> It is not possible to sync two interfaces if we don't have timestamped
> frame numbering (UST/MSC pairs). That means that we need to know, from a
> common clock, the time at which a (numbered) frame will be output or was
> input from a jack. Current time is not usable, because obviously there
> is an unknown delay between function calls. If the system is not able to
> produce timestamp/frame count pairs, there is no possibility to sync
> audio streams or audio to video streams. I have looked at JACK, and the
> situation is the same as with the ALSA API.
> 
> There are cards in the market with such timestamped operations supported
> in the hardware and proprietary APIs, but is there a way to accessing
> these operations from ALSA or JACK?
> 
> Thank you,
> 
> Alejandro
> 
> 

I think you are wrong. Just take a look at xine playing a DVD. The audio
and video are in perfect sync. It can be done with the current API.

James