nokhwa/examples/README.md

Examples

capture

Capture is a command line application designed to test features of backends to see if they are implemented correctly. For the UVC backend, you may need to run the app as admin.

Capture - Usage

<> indicates an optional parameter. [] indicates a mandatory one.

• -q <BACKEND>/--query <BACKEND>: Queries the system for available devices. If <BACKEND> is set, it will query using that backend.
• -c <DEVICE>/--capture <DEVICE>: Captures using device. If <DEVICE> is set, it will using that device index or IP.
• -s/--query-device: Show device queries from compatible_fourcc and compatible_list_by_resolution. Requires -c to be passed to work.
• -w [WIDTH:U32]/--width [WIDTH:U32]: Set width of capture to [WIDTH:U32]. Does nothing if -c flag is not set. Value Has to be a u32
• -h [HEIGHT:U32]/--height [HEIGHT:U32]: Set height of capture to [HEIGHT:U32]. Does nothing if -c flag is not set. Value Has to be a u32
• -rate [FPS:U32]/--framerate [FPS:U32]: Set FPS of capture to [FPS:U32]. Does nothing if -c flag is not set. Value Has to be a u32
• -4cc [FORMAT]/--format [FORMAT]: Set format of capture to [FORMAT]. Does nothing if -c flag is not set. Possible values are MJPG and YUYV. Will be ignored if not one of those two.
• -b [BACKEND]/--backend [BACKEND]: Set the capture backend to [BACKEND]. Pass AUTO for automatic backend, UVC to use UVC, V4L to use Video4Linux, GST to use Gstreamer, OPENCV to use OpenCV.
• -d/--display: Enable glium display. Note: This is currently bugged as it shows an upside down feed. It also does not respond to x button press from window. (FIXME)

Example Usage:

./capture -q V4L -c 0 -s -w 1920 -h 1080 --framerate 30 --format MJPG -b V4L -d

Query system using V4L backend, capture device with index 0 at 1920x1080 @ 30 FPS on MJPG format, using backend V4L, then display to glium window.