On Mon, Nov 16, 2009 at 10:01 AM, Sietse Achterop <s.achterop@xxxxxx> wrote: > Dear all, > > Context: > debian/lenny with usb frame grabber: > Zoran Co. Personal Media Division (Nogatech) Hauppauge WinTV Pro (PAL/SECAM) > This uses the usbvision driver. > > The problem is that while xawtv works OK with color, v4lctl ONLY shows the frames > in black-and-white. > > I understood that the usbvision driver needs some attention, e.g. a command like > "v4lctl setinput 2" is not working, it will keep using setting 0. > Because I need 2 (S-video) I patched the driver to always use 2 by setting > channel=2 in "usbvision_muxsel" to permanently select that channel. > With that usbvision module loaded I am getting pictures, but in BLACK_AND_WHITE, > as mentioned. > > When starting "xawtv", it works fine! > > With a simple opencv application I do an > CvCapture* capture = cvCaptureFromCAM( cnum ); > ... > cam = (CvCaptureCAM_V4L*)capture; > ... > ioctl(cam->deviceHandle,VIDIOC_G_FMT,&format)) > ... > and find that the format is YV12, but the picture is black-and-white. > But YV12 is a color format. > > The question is, how to get proper color pictures when using v4lctl or other > simple applications with this driver. > > Thanks in advance, > Sietse Achterop I don't know about that board in particular, but on some boards the composite and s-video are actually wired together (sharing the luma line), so if you have the device configured in "composite" mode but have the s-video plugged in, then you will get a black/white image (since it expects to see both luma/chroma on the one pin that provides luma). I had this issue on the HVR-950q. Devin -- Devin J. Heitmueller - Kernel Labs http://www.kernellabs.com -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
