Hi Alexandre, On Mon, 29 Jan 2007 13:50:28 -0800, Alexandre DENIS <[EMAIL PROTECTED]> wrote:
> I would believe that the following extended controls should actually be > mapped onto standard V4L2 controls : > > "Exposure, Auto" = V4L2_CID_AUTOGAIN > "Exposure (Absolute)" = V4L2_CID_EXPOSURE > "White Balance Temperature, Auto" = V4L2_CID_AUTO_WHITE_BALANCE > "White Balance Temperature" = V4L2_CID_GAMMA > > Or am I missing something? There is still some ongoing discussion (euphemism alert) on how to best map UVC controls (the USB Video Class spec defines quite a few) to V4L2 controls. The fact is that V4L2 controls are not even kinda close to what we need for the UVC driver. If you have a strong opinion on that or any helpful arguments, then feel free to speak up on the v4l-list (https://www.redhat.com/mailman/private/video4linux-list/2007-January/thread.html, search for "New control identifiers"). We're especially looking for people with a background in photography/imaging. Back to your e-mail, though. :-) We'll certainly review these controls once V4L2 is updated. In the meantime a few notes: - White balance can be specified in temperature or a red/blue channel correction. But Gamma correction is a completely different story. - Gain and exposure time are often related, but, in camera terms, are two different controls. - There is relative and absolute exposure time. V4L2 does not specify what V4L2_CID_EXPOSURE means. Cheers, Martin _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
