Hi Michael, On Thursday 06 November 2008, Michael wrote: > Hey > > I'm trying to use video4linux2 to control a Logitech QuickCam Pro 9000. The > camera supports UVC and I can get the image just fine. However, I'm having > issues with the controls. > > Luvcview reports the following controls: > > V4L2_CID_BASE (predefined controls): > index:9963776 name:Brightness type:1 min:0 > max:255 step:1 def:128 now:128 > index:9963777 name:Contrast type:1 min:0 > max:255 step:1 def:32 now:32 > index:9963778 name:Saturation type:1 min:0 > max:255 step:1 def:32 now:32 > index:9963788 name:White Balance Temperature, Auto type:2 min:0 > max:1 step:1 def:1 now:1 > index:9963795 name:Gain type:1 min:0 > max:255 step:1 def:0 now:0 > > > There are no driver specific controls. The problem is that there are some > missing. There should also be Auto Exposure on/off, manual exposure, > autofocus on/off and manual focus. > > The strange thing is that luvcview will let me turn off auto exposure > (strangely by pressing the on button), and will also let me set the > exposure manually. > > I would like to know if there is a way to access these controls using > video4linux?
Yes there is. luvcview uses an old control enumeration method that results in controls being missed. It should instead use the V4L2_CTRL_FLAG_NEXT_CTRL flag as explained in the V4L2 specification. Regardless of enumeration issues, controls can be accessed through VIDIOC_G_CTRL and VIDIOC_S_CTRL. Best regards, Laurent Pinchart _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
