video 4 linux 2 notes

V4L2 -- Video For Linux Version Two

UVC

For a list of cameras that support UVC see the official Linux UVC site. Full UVC support in Linux:

I have been using a Logitech HD Pro Webcam C910, USB Device ID: 046d:0821, for my tests.

Gstreamer

See gstreamer.

Capture video and modify settings at the same time

Start `guvcview` with the --control_only option to display a GUI dialog to edit camera settings. This will work while another video display or capture application is already running.

guvcview --control_only --device=/dev/video0

fswebcam

`fswebcam` is a small and simple tool for grabbing still images from a camera. The world needs more apps like this. It can grab a single image or grab sequences of images in a loop. It can save images to a file or pipe them to stdout.

fswebcam --png --save fswebcam-test.png

Common UVC patterns with `uvcdynctrl`

apt-get install uvcdynctrl
uvcdynctrl --device=/dev/video1 --clist
uvcdynctrl --device=/dev/video1 --get='Focus, Auto'
uvcdynctrl --device=/dev/video1 --set='Focus, Auto' 0
uvcdynctrl --device=/dev/video1 --set='Focus (absolute)' 20

See also

• Mplayer_notes#Webcam_preview_--_play_raw_video_stream_from_video_device
• Mplayer_notes#Record_video_directly_from_video_device