v4l2-ctl: add page (#7099)

pages/linux/v4l2-ctl.md

@@ -0,0 +1,32 @@
+# v4l2-ctl
+
+> Control video devices.
+> More information: <https://manned.org/v4l2-ctl>.
+
+- List all video devices:
+
+`v4l2-ctl --list-devices`
+
+- List supported video formats and resolutions of default video device `/dev/video0`:
+
+`v4l2-ctl --list-formats-ext`
+
+- List supported video formats and resolutions of a specific video device:
+
+`v4l2-ctl --list-formats-ext --device {{path/to/video_device}}`
+
+- Get all details of a video device:
+
+`v4l2-ctl --all --device {{path/to/video_device}}`
+
+- Capture a JPEG photo with a specfic resolution from video device:
+
+`v4l2-ctl --device {{path/to/video_device}} --set-fmt-video=width={{width}},height={{height}},pixelformat=MJPG --stream-mmap --stream-to={{path/to/output.jpg}} --stream-count=1`
+
+- Capture a raw video stream from video device:
+
+`v4l2-ctl --device {{path/to/video_device}} --set-fmt-video=width={{width}},height={{height}},pixelformat={{format}} --stream-mmap --stream-to={{path/to/output}} --stream-count={{number_of_frames_to_capture}}`
+
+- List all video device's controls and their values:
+
+`v4l2-ctl --list-ctrls --device {{/path/to/video_device}}`