On Tue, 17 Apr 2007 14:27:02 +0300 (EEST)
Vesa Solonen <[EMAIL PROTECTED]> wrote:


> On Mon, 16 Apr 2007, Attila Kinali wrote:
> 
> > The issue of stream synchronus playback can be entirely
> > solved in software and does not need to be done in hardware.
> > Unless you need A-V sync below 0.5*frame-time, then you need
> > at least a little bit information from the graphics card, when
> > the current image drawing is finished, but any half decend card
> > supports this.
> 
> The problem is _not_ A-V sync, but interference jitter between different 
> frame rates. Please have alook at:
> 
> http://www.linuxtv.org/wiki/index.php/The_DVB_Decoder_Challenge#Screen.2FDecoder_Sync_Aliasing

Nice explanation, but it's wrong IMHO. First you need to
realize that frames in video codecs are sampled _below_
the niquist criteria. That's why there is a need for 
motion compensation. The second thing is that human
eyes don't work like ears, they don't percieve movements
as signal modulations. So the whole argumentation
about niquist frequency while showing movies falls flat.

As i said before, the only issue here involved is keeping
high a-v sync ratios. As long as the refresh rate of the
monitor is as high as the frame rate of the video, you can
safely ignore any difference between those two.

                        Attila Kinali


-- 
Linux ist... wenn man einfache Dinge auch mit einer kryptischen
post-fix Sprache loesen kann
                        -- Daniel Hottinger
_______________________________________________
Open-graphics mailing list
[email protected]
http://lists.duskglow.com/mailman/listinfo/open-graphics
List service provided by Duskglow Consulting, LLC (www.duskglow.com)

Reply via email to