> It's up to the driver writer. I really don't think this needs to be > dictated. I think it should be clear for a application how a driver reacts. Otherwise we will get small but annonying incompatibilities between drivers ... > if there is no data in the throw buffer, or the data in the throw > buffer is "too old" then initiate a new frame capture. If it was a > blocking read() then sleep, else return an error code (I forget which). "too old" being how much? one second? > I guess for non-blocking read() capture, the driver would have to > automatically initiate a capture on a read() call or else implement > blocking read() and non-blocking read() the same way. That latter is not > as bad as it sounds, because the video source produces frames > continuously, so, in a sense, there is always data to be read. ... with a delay between 40 and 80 ms in case of bttv 0.8.x and PAL, which is alot (close to 0.1 second in the worst case). Gerd -- Gerd Knorr <kraxel@xxxxxxxxxxx> -- SuSE Labs, Außenstelle Berlin
