Hi, > Therefore I'm thinking about using USB2 webcams, such as the Logitech > Fusion or Pro 5000, to increase the overall framerate I can archive with > this driver. The question now is, which framerate could I expect from 5 > UVC USB2 cameras connected to a single laptop? Or is there a principal > problem of using that amount of cameras at the same time?
I don't have the equipment to do this test with me at the moment but to give you something to work with: - The UVC overhead is minimal. - There is obviously some USB overhead but it should be rather small compared to the video stream. - In YUV mode, the size of one frame is 1.5*height*width. - In MJPEG mode, the size is somewhat unpredictable but obviously tends to be much smaller. You can test this using the -c option of luvcview. This should give you an idea of the amount of data you have. Whether your PC can handle it, is a whole other story. :-) > On > https://lists.berlios.de/pipermail/linux-uvc-devel/2006-March/000365.html, > David Moore noticed: >> Hi, I'm interested in connecting more than one camera at once, >> specifically, a pair of Logitech Quickcam Pro 5000s. >> I only have one at the moment, but when I run it at full uncompressed >> resolution (640x480x30fps YUV), it chooses an ISO endpoint with a packet >> size of 3060 bytes. This is more than half of the available ISO >> bandwidth. (cat /proc/bus/usb/devices claims it's 60%) I'm not sure if this is indeed a problem because, IIRC, Linux does not enforce isoc bandwidth constraints unless explicitly told to do so (experimental kernel compile-time option). So, if your camera did not use the entire 60%, it should still be available for other cameras. > Is there a compression method supported by the cameras (for example > MJPEG), that would lead to higher compression, thus allowing a higher > total framerate? Yes, MJPEG is supported by all Logitech UVC cameras. Cheers, Martin _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
