Greetings, Some background: our company develops video surveillance systems and at the moment we are in the process of switching development platform to Linux. Some time ago I tried to get a WinNT machine to use two Hauppauge Impact PCI cards but could not get it right. I contacted Hauppauge but they said "it is not possible to use two cards as hardware conflicts will occur." Yesterday I put two cards in a Linux machine (Best Linux 2000 R2) and in no time I had two overlays on screen with CPU at 0% most of the time. Perfect. Now I want to do the following: have one card do the overlay and the other (or maybe two others, or more) do single-shot grabs a'la time-lapse recorder. The incoming raw images from this other card must be compressed and I am going to use some kind of compression board, maybe one based on the Analog Devices ADV-JP2000 (that is, if they write Linux drivers for it.) What must happen is this: order this other card to grab in to some buffer allocated by me, then feed that image data to the compressor board and read compressed images back and write them to disk. Simply put. I would also like to allocate many buffers and switch the target on the fly, to implement a circular buffer. Is this possible? I tried to follow this "Userspace DMA" thread but it got too deep for me to consume. Thanks folks, Joni Kähärä Visi-Radio Oy KOTKA, Finland
