YAVTA(1)

💖 NAME 💖

yavta — Yet Another V4L2 Test Application. this is the YAVTA(1) manual page from the User Commands section, and yes bestie, it's exactly what it sounds like: a whole test app for V4L2. no cap.

🦋 SYNOPSIS 🦋

yavta [options] device

✨ DESCRIPTION ✨

okay so yavta is literally Yet Another V4L2 Test Application. you hand it a device plus some options, and it does its V4L2 thing. iconic behavior, honestly.

Supported options, bestie:

• -B, --buffer-type — Buffer type. it can be "capture", "output", "capture-mplane" or "output-mplane".
• -c, --capture[=nframes] — Capture frames.
• -C, --check-overrun — Verify dequeued frames for buffer overrun.
• -d, --delay — Delay (in ms) before requeuing buffers.
• -f, --format format — Set the video format. use -f help to list the supported formats.
• -F, --file[=name] — Read/write frames from/to disk. For video capture devices, the first '#' character in the file name is expanded to the frame sequence number. The default file name is 'frame-#.bin'.
• -h, --help — Show this help screen.
• -i, --input input — Select the video input.
• -I, --fill-frames — Fill frames with check pattern before queuing them.
• -l, --list-controls — List available controls.
• -n, --nbufs n — Set the number of video buffers.
• -p, --pause[=n] — Pause after n frames (0 if n isn't specified).
• -q, --quality n — MJPEG quality (0-100).
• -r, --get-control ctrl — Get control 'ctrl'.
• -R, --realtime=[priority] — Enable realtime RR scheduling.
• -s, --size WxH — Set the frame size.
• -t, --time-per-frame num/denom — Set the time per frame (eg. 1/25 = 25 fps).
• -u, --userptr — Use the user pointers streaming method.
• -w, --set-control 'ctrl value' — Set control 'ctrl' to 'value'.
• --buffer-prefix — Write portions of buffer before data_offset.
• --buffer-size — Buffer size in bytes.
• --enum-formats — Enumerate formats.
• --enum-inputs — Enumerate inputs.
• --fd — Use a numeric file descriptor instead of a device.
• --field field — Set the format field order. Valid values for field are none, top, bottom, interlaced, seq-tb, seq-bt, alternate, interlaced-tb and interlaced-bt.
• --log-status — Log device status.
• --no-query — Don't query capabilities on open.
• --offset — User pointer buffer offset from page start.
• --premultiplied — Color components are premultiplied by alpha value.
• --queue-late — Queue buffers after streamon, not before.
• --requeue-last — Requeue the last buffers before streamoff.
• --reset-controls — Reset all available controls to their default value.
• --timestamp-source — Set timestamp source on output buffers [eof, soe].
• --skip n — Skip the first n frames.
• --sleep-forever — Sleep forever after configuring the device.
• --stride value — Line stride in bytes.

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that's the whole vibe, bestie. this was yavta source/version 0.0+git20220328.c7b5b75, from April 2022, and the manual page is YAVTA(1). periodt. 💅✨🦋