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Working with video

Video recording


H.264 is available on Pi 3 and Pi 4. Older boards won't handle it. Best of all this feature only works for HDMI to CSI bridge. For the USB HDMI dongle, there will be a decrease in FPS to 10-15 for 1080p.

  1. Update OS:

    Updating PiKVM OS

    To update, run following commands under the root user:

    [root@pikvm ~]# pikvm-update

    If you encounter an error like:

    [root@pikvm ~]# pikvm-update
    bash: pikvm-update: command not found

    It's most likely you have an old OS release. You can update the OS as follows:

    [root@pikvm ~]# rw
    [root@pikvm ~]# pacman -Syy
    [root@pikvm ~]# pacman -S pikvm-os-updater
    [root@pikvm ~]# pikvm-update

    Next time you will be able to use the usual method with pikvm-update.

  2. Install ffmpeg:

    # rw
    # pacman -S ffmpeg
  3. For USB dongle only: Add line gpu_mem=256 to /boot/config.txt.

  4. Perform reboot command.

  5. Run rw after the reboot.

  6. To record a video, you need to enable the stream (open the web interface or connect via VNC). Then run something like this in the console:

    # rw
    # ustreamer-dump --sink kvmd::ustreamer::h264 --output - | ffmpeg -use_wallclock_as_timestamps 1 -i pipe: -c:v copy test.mp4
  7. Press Ctrl+C to stop recording. Your video will be in the file test.mp4.

  8. After finishing work, do not forget to switch the file system to read-only mode using ro command.

Take a screenshot via console on PiKVM


You must have a stream running

# curl --unix-socket /run/kvmd/ustreamer.sock http://localhost/snapshot -o /tmp/screen.jpg