I have a Logitech C920 webcam connected to my computer running Debian Linux. I want to access the stream by using mplayer (/dev/video0) and it works out of the box. However, the saturation/brightness/other settings are not correct, so I use guvcview to set the proper configuration.
If I keep the preview window from guvcview open, I can't connect to the stream anymore because the device is busy (= in use by guvcview). mplayer returns an error. If I close guvcview my settings are gone and the stream is 640x480 again (instead of 1280x720). I get the same error when using openCV to connect to the stream:
- without guvcview: connected, but bad settings
- with guvcview running: good settings, but can't connect to /dev/video from any other programs (blocked by guvcview)
Here are some parts of the console output when setting the configuration in guvcview. I don't know if its helpful:
V4L2_CORE: Unable to find parent usb device.V4L2_CORE: Unable to find parent usb device.GUVCVIEW: version 2.0.4 V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device V4L2_CORE: failed to subscribe events for control 0x00980001: Inappropriate ioctl for device V4L2_CORE: failed to subscribe events for control 0x0098f900: Inappropriate ioctl for device Cannot connect to server socket err = No such file or directory Cannot connect to server request channel jack server is not running or cannot be started JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for 4294967295, skipping unlock JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for 4294967295, skipping unlock