I am trying to develop a DVB application which has a PIG (Picture In Graphic) feature common to most DVB-S IRDs. To achieve this I need to shrink the video down to 1/4th of the screen and place it in the upper right hand corner. After digging though some documentation it seems that this should be possible using v4l2 API (in fact there is example to do exactly what I'm trying to do
http://v4l2spec.bytesex.org/spec-single/v4l2.html#CROP). When I try to run this example I get an EINVAL error on the VIDIOC_CROPCAP ioctl(). I have a Nexus-S card which has an SAA7146 MPEG decoder so I looked at the saa7146_video.c file and noticed that it doesn't handle this ioctl() which seems to be the cause of the EINVAL error. Is there any other way to accomplish what I'm trying to do ? Am I even using the correct APIs to do what I'm trying to accomplish ? I looked at the SAA7146
documentation and it seems like it should be possible to scale the video output down to 1/4th the screen.