On Sun, 2002-01-06 at 05:04, Matthew Tippett wrote: > In some of webcam implementations, it looks like a frame is captured and > processed when a VIDIOCMCAPTURE ioctl is called. The frame is then freed > when a VIDIOCSYNC is called. VIDIOCMCAPTURE makes the buffer available for being filled with a frame by the driver/tv-card. VIDIOCSYNC waits for the frame to be filled so that you can start processing the frame. after that, you can re-queue it using VIDIOCMCAPTURE so that a new frame can be written in the buffer. VIDIOCMCAPTURE thus makes the buffer available to the kernel (to be written on) and VIDIOCSYNC makes the buffer available for the application (to be processed). Ronald -- - .-. - /V\ | Ronald Bultje <rbultje@xxxxxxxxxxxxxxxxxxx> - // \\ | Running: Linux 2.2.19 and OpenBSD 2.8 - /( )\ | http://ronald.bitfreak.net/ - ^^-^^
