[mythtv-users] what resolution is mythui with a PCI VDPAU video card?

Raymond Wagner raymond at wagnerrp.com
Sat May 15 00:27:07 UTC 2010

On 5/14/2010 20:12, Brian J. Murrell wrote:
> Just doing the math, a 132MB/s PCI bus should be able to carry 63 bytes
> for every pixel on the screen:
> 132000000/(1920*1080) = 63
> Why is that not enough for even raw HD?  Not that I really care about
> being able to push raw HD, but I would like my UI at 1920x1080 on my
> panel.

You missed a couple steps there.  That's at 60fps, and three colors per 
pixel at one byte each.  Now technically, we're using YUV, so you halve 
that bitrate, but youre still talking about ~190MB/s, on a bus that can 
only theoretically hit 133MB/s.

Now the UI is not going to be full motion video, so it won't need 
anything like that kind of bandwidth, but you still need enough 
bandwidth to send whatever your video content is unscaled (Xv does 
scaling on the video card).

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