[vdr] Re: kvdr-0.61 and xv?

[Guido Fiala <gfiala@s.netic.de>]

On Saturday 05 June 2004 10:33, Gregoire Favre wrote:
> Well, I don't know exactly... The problem I have with kvdr is that I
> have perfect video, than a small glitch, then perfect video, then a
> glitch... which is just annoying.

Now it's more clear - it has something to do with the synchronising between 
video and Monitor. I will try using select() and see if that makes it any 
better. But there is another effect - see below.

> Well, my solution for know is to use xv in 1600x1200@75 Hz which produce

50Hz of kvdr does not mean that it can only be used at 50Hz screen-refresh 
rate. However - if the 50Hz from TV are displayed at an higher rate and this 
happens unsynchronized you get aliasing effects in time:

It is the same thing that makes turning wheels in movies backwards.

There are 2 solutions to this:
1. synchronize it (there is a hack for certain graphics cards which generate a 
interrupt at every frame which can be used for synching)
2. use a refresh frequency that is much higher than the video-frequency and is 
far away from even factors - 85 Hz would probably give better results.

> a perfekt video with xawtv (but it lacks pip that I really like from
> your kvdr).

Implementing PiP / Multipicture was in Xv even more easy than as overlays - it 
just copies some bytes from the secondary image into the buffer before 
scaling, you might ask the author of xawtv...

>
> Maybe you could explain me why if I open another xawtv with
> xawtv -c /dev/v4l/video1 -noxv -geometry 154x116+1395+241 &
> I only get a black screen?

sorry no, i would understand if if where not "noxv"