Thank you verey much for your answer. Anyway, opencv has functions to adjust such parameters; they just don't work most of times. I'll try your mods, but I've also managed to convert some raw v4l2 code to a wrapped c++ library, providing a neat interface with opencv bindings. Its a pretty useful class for quick coding of a video capture application, hence I'm going to publish it opensource; I think it would be very useful for people like me, who need simple interfaces to manipulate video streams without having to study whole v4l2 apis. :)
Giacomo On Monday, June 8, 2009, Laurent Pinchart <[email protected]> wrote: > Hi Giacomo, > > On Saturday 06 June 2009 15:10:17 SpiglerG wrote: >> Hi. >> I've just bought a Minoru3D webcam (which recently got supported by >> UVCVideo) to get a nice stereo platform, but I can't manage to get it >> working because of the known-problems about "VIDIOC_STREAMON error 28, No >> space left on device", even thought I'm using the uvcvideo-50059a68c503 >> (last) driver. >> Actually I've managed to get it working with a modified version of >> fswebcam, and only at 320x240, but I can't make it work with OpenCV: I >> can't change resolution to 320x240 (default is 640x480), and at default >> resolutions it fails (it's probably trying to get images @ 30fps). >> UVC currently supports acquisition up to 320x240 @ 30fps, and 640x480 >> @15fps, but default specs are 640x480 @ 30fps, which gets usb bandwidth >> errors. >> Do you know any possible fixes to have it work with OpenCV (simultaneous >> streaming), > > I'm not too familiar with OpenCV. If it doesn't provide a way to change the > frame rate, I think you can try to cast your CvCapture object to a > CvCaptureCAM_V4L object and call the VIDIOC_S_PARM ioct directly on > CvCaptureCAM_V4L::deviceHandle. > >> or to set 15fps as default for such resolution with this webcam >> modifying UVC driver (at least for personal usage)? > > Assuming OpenCV calls VIDIOC_S_PARM, it should be easy to modify the ioctl > handler and overwrite the requested frame rate with 15fps. > > Best regards, > > Laurent Pinchart > > _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
