[Motmot] motmot.cam_iface + isight + snowleopard

[Andrew Straw]

On 4/8/10 1:10 AM, Laurent Perrinet wrote:
> Hi list!
>
> I have achieved to install the libcamiface libraries + python interface on a macosx 10.6 without a problem / It allows me to grab a frame from my isight from within python in a few lines:
>
>    
Great!

> this works very well. I wondered: is it possible to set the size of the image to be grabbed before hand? I'm interested in grabing smaller images with higher fps.
>    
It's not clear to me from the above what backend you used -- quicktime? 
If it is quicktime, there's no support for setting the region of 
interest (ROI) in libcamiface. (I'm not sure quicktime itself allows 
it.) However, if it's the libdc1394 backend, there you can definitely 
set the ROI for faster frame rates if the camera allows it.

Some cameras, although you cannot set the ROI, allow you to start them 
in different capture modes, which might do pixel binning or restrict the 
image to a conventional format (e.g. 640x480 on a sensor that allows 
656x491). In some cases, you might be able to get higher framerates that 
way, although I cannot remember if Quicktime itself supports anything 
like that.

Best regards,
Andrew

-- 
Andrew D. Straw, Ph.D.
California Institute of Technology
http://www.its.caltech.edu/~astraw/