Hi,
Does bttv support Cropping of the video image at capture time?

This would allow me to grab for example a 320x256 pixels
from the centre of my camera image and output them as a 320x256 image
The bt848 does no scaling down, and I get a 'digital zoom' on the
centre of the image.


 This is documented in Bt848 and Bt878 PDF datasheet, 
 Fig 15 Effect of the Cropping and Active Registers.


Previously I have grabbed the full 768x576 image (scale 1:1)
and then copied out just the pixels I need.
I do image compression and do not want to waste the CPU time.


Does bttv support it?

Looking at the V4L ioctls, I could not see one to set this up.
The only width/height options are for the scaled output image.
I'd need to set the crop regsion (active region) width, height
and X and Y offsets into the 768x576 image


Thanks
Roger
--
Roger Hardiman
Strathclyde Uni Telepresence Research Group, Glasgow, Scotland.
http://www.telepresence.strath.ac.uk      0141 548 2897
[EMAIL PROTECTED]


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