On Fri, 26 Sep 2003, Tuukka Toivonen wrote: > On Fri, 26 Sep 2003, Johnny Strom wrote: > > >so my question is the bandwith enough on the PCI bus to start a capture > >of four .jpeg files from four cards at the same time and then sleep for > >one second after the capture? > > Yes, jpeg compressed images don't use much bandwidth (if the compression is > performed in hardware before the image gets into main memory). > > >01:00.0 Multimedia video controller: Brooktree Corporation Bt878 Video > >Capture (rev 11) > > ...but Bt878 can't do hardware compression. So I suppose the drivers > actually capture uncompressed and compress in software. Let's say it's PAL > resolution 768x576@25fps 4:2:0 = 16 MB/s, or 64 MB/s for four > simultaneous captures. PCI bandwidth (IIRC) is 133 MB/s, so in theory it > would work. In practice... it's difficult to say. If you have decent hardware. For those of us with 1x AGP busses, and not 4x ... :( Speaking of which - I have no such problems with 1x capture on a 33MB PCI bus. -- TimC -- http://astronomy.swin.edu.au/staff/tconnors/ I'm sorry, but all questions must be in the form of a question. -- pieceoftheuniverse
