The Raspberry Pi is an inexpensive Linux computer which you can for example use to play back videos (up to Fill-HD). This page shows you how to set it up:
Making the RapberryPi run a video at startup
Install The Raspbian image (NOOBS is okay for the beginning, but it wastes a bit space on the SDcard for the recovery image which we don't need. Copy the raspbian on the card.
Once that is done, connect to the Internet (Ethernet + DHCP) and bring the OS up to date:
sudo apt-get update sudo apt-get upgrade sudo apt-get dist-upgrade sudo apt-get install raspberrypi-net-mods
Test video playback: source
omxplayer /opt/vc/src/hello_pi/hello_video/test.h264
add option -r to change display frame rate and resolution to the one that the movie file has:
omxplayer -r /opt/vc/src/hello_pi/hello_video/test.h264
make a file startup_script.sh (shell script) with the following content:
clear echo "Startup script running" echo "some useful information here" sleep 2 omxplayer -r movie.mp4 --loop
you will have to make this executable with
sudo chmod 775 startup_script.sh
and you can test if it works by running it
./startup_script.sh
Make it log in automatically
You don't want a password prompt when the raspberry boots source
Edit the inittab file.
sudo nano /etc/inittab
Disable the getty program. Find this line and comment it our by adding a # at the beginning of the line
#1:2345:respawn:/sbin/getty 115200 tty1
Add login program to inittab. Add the following line just below the commented line
1:2345:respawn:/bin/login -f pi tty1 </dev/tty1 >/dev/tty1 2>&1
This will run the login program with pi user and without any authentication
Save and Exit.
Make it start the script automatically:
sudo nano .bashrc
and right at the end put:
if [ $(tty) == /dev/tty1 ]; then ./startup_script.sh fi
(that last 'if' makes sure the script is not starting in an x session)
Synchronizing multiple RaspberryPi
maybe you want to have the different Pi different host names, so you don't get confused
sudo raspi-config
install pexpect:
sudo apt-get install python-pexpect
install python bindings for DBUS https://github.com/LEW21/pydbus
sudo apt-get install python3-setuptools sudo wget https://github.com/LEW21/pydbus/archive/master.zip sudo unzip master.zip rm master.zip cd pydbus-master/ sudo chmod 777 setup.py sudo ./setup.py build sudo ./setup.py install
sudo apt-get remove omxplayer sudo rm -rf /usr/bin/omxplayer /usr/bin/omxplayer.bin /usr/lib/omxplayer sudo wget -O- http://yokto.net/0/omxplayer/omxplayer-3176db4.tar.bz2 | sudo tar -C / -xjvf - sudo ln -sf /lib/arm-linux-gnueabihf/libpcre.so.3 /lib/arm-linux-gnueabihf/libpcre.so.1 sudo wget -O /usr/bin/omxplayer-sync https://github.com/turingmachine/omxplayer-sync/raw/master/omxplayer-sync sudo chmod 0755 /usr/bin/omxplayer-sync sudo wget https://github.com/turingmachine/omxplayer-sync/raw/master/synctest.mp4
Make a local network, connect them with Ethernet cable (+Hub if more then two) and configure static IPs source
sudo nano /etc/network/interfaces
start on master:
omxplayer-sync -mubv synctest.mp4
start on slave:
omxplayer-sync -lubv synctest.mp4
-b flag to make screen background black
(remove v for verbose mode later once everything works)
Timing
Set the time
dpkg-reconfigure tzdata
Note that the Raspberry is searching online for the current time when booting. If there is no Internet the time might not be accurate.
Shut down at specific time
The shutdown command has a timer built in, so when it is called like this
sudo shutdown -h 15:00
the system will shut down at three in the after noon.
sudo shutdown -h +30
will shut the system down in 30 minutes from now.
You can also set a cron job for shutting down on specific days at specific times.
sudo crontab -e
add this line:
45 18 * * * /sbin/shutdown -h now
to shut down 45mins past 6PM
Backup and copy
let's say /dev/mmcblk0 is your card reader
make a backup of SDCard:
sudo dd if="/dev/mmcblk0" of="Pi.bin"
put backup on card:
sudo dd bs=4M if=Pi.bin of=/dev/mmcblk0
(both these commands take a long time and the terminal seems like frozen, there is no progress feedback)
Power
to switch on just plug in the power. Make sure HDMI is connected first and Beamer/Screen is on prior to plugging in the power, otherwise the screen might not be recognized.
reboot:
sudo reboot -h
shutdown:
sudo shutdown -h now
Notes
other resources
Use multiple RasberryPis to make a video wall (needs one extra server-Pi, plus one Pi per client) Piwall