Hello, I've got an Hauppauge BT878 based card, i was trying to write a simple app to display captured TV frames. The app goes like this : I call ioctl VIDIOCMCAPTURE, to start the capture and then ioctl VIDIOCSYNC. The problem comes from the fact that the call takes 100ms to return, time that is far too slow to be acceptable. I've tried then to use several buffers (four). I then call four times VIDIOCMCAPTURE and then call VIDIOCSYNC four times. The first call to VIDIOCSYNC still takes about 100ms, and the subsequent calls take a bit less than 40ms. This is too slow for a TV app too. My understanding is that when you call VIDIOCMCAPTURE, it starts the capture on the device, so why do the 2nd, 3rd and 4th frames take so long to grab? Any hints? Do you have links that describe the hardware and could give an explanation? Thanks in advance, Frederik Deweerdt
