ROS Node wrapped around popular MPV video player

With this ros node an instance of MPV video player can be started using the configured ROS parameter.
Additionaly a MPV ipc-server.sock will be opened which can be accessed directly or via a topic. Responses from MPV player can be received and are also published via a topic.
Use the full MPV functionality within ROS to add additional dynamic visuals for the robot operator.

A lot of functions are availabe with MPV player. Here are some of them:

• Play video, audio and streams
• Sending commands to the player during playing
• Retrieve state information of the player
• Scaling of video
• Positioning of the video window
• Remove of the window borders or even window caption
• Playing just part of the Video
• OSD functions
• Configurable keyboard controls
• ...

Additional information can be found here:

• https://mpv.io
• https://mpv.io/manual/stable

Dependencies

# install MPV video player
sudo apt-get install mpv

Setup package

# run in your ros2_ws/src folder
git clone https://gitlab.com/bob-ros2/mpvros.git
cd ..
colcon build
. install/setup.bash

ROS Node MPV

Usage

# show scaled video without border centered on the screen
ros2 run mpvros mpv --ros-args -p "args:=['/home/ros/video.mkv','--no-border',
'--window-scale=0.5','--geometry=50%:50%']"

# run with custom ipc-server socket path
ros2 run mpvros mpv --ros-args -p "ipc_server:=/home/ros/.mpvros.sock" -p 
"args:=['/home/ros/video.mkv']"

Node Parameter

~ipc_server (string, default: "/tmp/mpvros.sock")
Server socket to be used for ipc communication.

~args (string_array, default: [])
Command line options to be passed to MPV player. Currently spaces are not allowed in the array items. See also https://mpv.io/manual/stable

Subscribed Topics

~ipc_in (std_msgs/String)
Incoming ipc data to be forwarded to MPV ipc-server socket.

Published Topics

~ipc_out (std_msgs/String)
Outputs received ipc data from MPV ipc-server socket.

ROS Node Title

The title node updates periodically the current running MPV player title. This works for single file and for playlists. The current title is published to a topic.

Usage

# start title node
ros2 run mpvros title

# start with remapping
ros2 run mpvros title --ros-args -r ipc_in:=/mpv1/ipc_in -r ipc_out:=/mpv1/ipc_out

Subscribed Topics

~ipc_in (std_msgs/String)
Incoming ipc data from MPV player.

Published Topics

~title (std_msgs/String)
Outputs current title.

~ipc_out (std_msgs/String)
Outgoing ipc data to request current title.

ROS Node Scheduler

The Scheduler node can be used as central point to start and maintain running MPV playing orders.

Usage

# start scheduler to wait for incoming MPV playing orders
ros2 run mpvros scheduler

# publish a playing order to the scheduler topic
ros2 topic pub --once /schedule std_msgs/msg/String "{data: '/your/path/vid.mp4 --no-border --window-scale=0.4 --geometry=50%:50% --loop=inf'}"

# send playing order via action service, if parameter id is filled a single instance with this id will be forced
ros2 action send_goal /SuperBob/schedule mpvros/action/Schedule "{id: bob, args: /path/to/video.mkv --loop=inf --geometry=50%:50% --window-scale=0.4 }"

Subscribed Topics

~schedule (std_msgs/String)
Receive schedule order.

Published Topics

~done (std_msgs/String)
Publishes MD5 sum of the schedule order which finished the job.

Launch Files

MPV.LAUNCH.PY

Usage

# start MPV player node and title node via launch file
ros2 launch mpvros mpv.launch.py args:="['/home/ros/Videos/bob.flv']"

Arguments

~args (Array, default: None)
Array with MPV command line arguments. At least one array item must be provided.

~title (Bool, default: true)
Wheather to start also title node or just the MPV player node. If MPV player ends also the title node will be shutdown and the launch script ends as well.

~ns (String, default: /)
Namspace to start node(s) within.

~ipc_server (String: default: /tmp/mpvros-$RAND.sock)
Override MPV IPC server socket path.

Miscellaneous

# this ffmpeg example will create a 10 second test video, 30 fps
ffmpeg -f lavfi -i testsrc=duration=10:size=1280x720:rate=30 testsrc.mpg

# send a command from shell via topic ipc-in, the result can be retrieved 
# ia topic ipc-out
# see also https://mpv.io/manual/stable/#json-ipc
ros2 topic pub --once /ipc_in std_msgs/String "data: '{ \"command\": [\"get_property\", \"playback-time\"] }'"

# send input.conf style text-only commands, this shows the playtime on 
# the player OSD
# this will not produce a reply in the ipc-out
ros2 topic pub --once /ipc_in std_msgs/String "data: 'show-text \${playback-time}'"

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change. Please make sure to update tests as appropriate.