from https://ubuntu-mate.org/raspberry-pi/
Re-size file system
Ubuntu MATE 16.04
You can use Ubuntu MATE Welcome to resize to automatically resize the partitions to make full use of your microSHDC card capacity. Simply click the large Raspberry Pi Information button on the Welcome screen, click the Resize button and then restart the Raspberry Pi.
Manual Method
It’s not hard to do manually. Once booted:
sudo fdisk /dev/mmcblk0
Delete the second partition (d, 2), then re-create it using the defaults (n, p, 2, enter, enter), then write and exit (w). Reboot the system, then:
sudo resize2fs /dev/mmcblk0p2
Enable and Disable X11
We created a simple utility called graphical to disable/enable the MATE desktop environment for easily creating a headless “server”. Executing graphical disable will present a console login on the next boot, with no X11 or associated services running. If you want to get the full Ubuntu MATE desktop back, run graphical enable and reboot.
Hardware accelerated video with omxplayer
Most videos will play with hardware acceleration using omxplayer which is pre-installed in Ubuntu MATE. However if you have MPEG-2 or VC-1 video video files then you will need MPEG-2 and/or VC-1 licenses from the Raspberry Pi Store.
Redirecting audio output
You can select which audio device omxplayer should output audio to.
For HDMI
omxplayer -o hdmi video.mp4
For 3.5mm audio jack
omxplayer -o local video.mp4
The sound will output to HDMI by default if both HDMI and the 3.5mm audio jack are connected. You can, however, force the system to output to a particular device using amixer.
For HDMI
sudo amixer cset numid=3 2
For 3.5mm audio jack
sudo amixer cset numid=3 1
Hardware accelerated video with VLC and ffmpeg
Ubuntu MATE 16.04 added OpemMAX IL hardware accelerated video playback to VLC and MMAL hardware accelerated video playback to ffmpeg.
- To enable hardware accelerated video playback in VLC go to
Tools->Preferences->Videoand selectOpenMax IL. - To use hardware accelerated video playback with
ffplayyou must specify theh264_mmalcodecffplay -vcodec h264_mmal video.mp4
Hardware accelerated playback on the Raspberry Pi works by overlaying the video directly to the screen. Therefore there are no onscreen controls for playback control. You’ll need to use the VLC and ffmpeg keyboard shortcuts.