[pvrusb2] [patch] capture window centering via VIDIOC_S_CROP

[Mike Isely]

On Sat, 11 May 2008, Bjorn Danielsson wrote:

> A question: does this cropping reduce the bitrate, or increase the perceived
> MPEG quality at the same bitrate?
> 
> If not, isn't it better to just mask out those extra pixels during playback?

Not having tested this yet, I would presume this:  Removing unwanted 
information out of the signal up-front (i.e. cropping out pieces of the 
video) can only help.  That's information that would waste bandwidth 
otherwise so it's a good thing to get rid of it early.  The result 
should be either slightly lower bandwidth actually used or a slight 
increase in overall picture quality.  Either way that's a good thing.

I don't know the exact effects of the cropping yet; I still have to 
test.

  -Mike


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Mike Isely
isely @ pobox (dot) com
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