There’s lots of Raspberry Pi Digital Signage software suites available but most of them expect you to pay or are really out-dated.
This is a short guide on how to setup a small fleet of Raspberry Pis (Although most of the content applies to any Linux based system).
Simple Steps:
- Image your System – Raspberry Pi OS or Other Linux.
- Make sure your system displays correctly on your screen.
- Install Chromium or Google-Chrome.
- Run Chrome in Kiosk Mode.
- Restart Chrome every x minutes.
- Physically install your screen and pi.
I intend to run multiple systems to display different information signs with some of the systems being out of reach so they needed to be fairly robust stand-alone setup; if I wanted to change the content being displayed, then I needed a way to reconfigure this without having to re-image the raspberry pi or remove the signs.
The Signage Script
The signage bash script will try to detect the system mac address of the two possible system interfaces on a Raspberry Pi (feel free to add/edit these). The start url loads the web server php scripts below to allow changing of content at a later date. It will also detect google-chrome or chromium on the system and use which ever it finds.
The script runs in a loop, showing the web page for 30minutes (can be configured to anything else) and then restarts the browser; this means if there is an issue with network connectivity then you dont need to restart the entire system, it will be back in 30minutes or less.
#!/bin/bash
#
# Horrible Digital Signage Startup Script
# 2021 - Adam Boutcher - aboutcher.co.uk
#
STARTURL="http://my-server/tv/manager.php"
REFRESH=30 #Minutes
INTERFACES=(eth0 wlan0)
# Function to check that a binary exists
function check_bin() {
which $1 1>/dev/null 2>&1
if [[ $? -ne 0 ]]; then
echo "$1 cannot be found. Please install it or add it to the path. Exiting."
exit 1
fi
}
check_bin which
check_bin cat
check_bin awk
check_bin sleep
check_bin kill
check_bin echo
check_bin ethtool
# Looping through listed interfaces
for INT in ${INTERFACES[@]}; do
if [[ $(cat /sys/class/net/$INT/operstate 2>/dev/null) == "up" ]]; then
MAC=$(/usr/sbin/ethtool -P $INT | awk '{print $3}');
break
fi
done
if [ -z $MAC ]; then
echo "No MAC address found"
exit 1
fi
echo
echo Poor-Mans Digital Signage
echo Adam Boutcher - www.aboutcher.co.uk
echo
echo System MAC: $MAC
echo Starting URL: $STARTURL
echo Refresh in: $REFRESH Minutes
BROWSERS=("google-chrome" "chromium")
for BROWSER in ${BROWSERS[@]}; do
which $BROWSER >/dev/null 2>&1
if [ $? -eq 0 ]; then
echo Found Browser: $BROWSER
break;
fi
done;
while true; do
echo
$BROWSER --new-window --kiosk --ingognito $STARTURL?mac=$MAC >/dev/null 2>&1 &
if [ -z $WEBPID ]; then
WEBPID=$!
echo "First Start"
else
NEWPID=$!
sleep 0.5
kill -9 $WEBPID 2>/dev/null
WEBPID=$NEWPID
fi
echo Running on PID: $WEBPID
echo "Sleeping..."
sleep $((REFRESH*60))
echo "Restarting"
done
The Web Server Script
This a simple php logic script to redirect the system to your actual web content. This means that upon restart of the web browser, it will re-check this web server script for its content location.
<?php
// This array is key = mac, dest = value
$CLIENTS = array (
"dc:a6:32:zz:yy:xx" => "https://example.com",
"dc:a6:32:xy:zx:yz" => "https://aboutcher.co.uk",
);
if ( isset($CLIENTS[$_GET['mac']]) ) {
header("HTTP/1.1 302 Found");
header('Location: '.$CLIENTS[$_GET['mac']]);
} else {
echo "System not recognised.<br/>";
if ( !empty($_GET['mac']) ) {
echo $_GET['mac'];
} else {
echo "No mac";
}
}
?>
Raspberry Pi Auto Start:
Save this file in /home/pi/.config/autostart/signage.desktop
[Desktop Entry]
Type=Application
Name=Digital Signage
Exec=/home/pi/digitalsignage.sh
Raspberry Pi Tweaks:
You can disable screen blanking in the Raspberry Pi Configuration GUI as well as enable auto-gui and auto-login.
I would also recommend disabling SSH and VNC if remote access isn’t required; you can also enable the filesystem to be read-only which should save the SD card’s life span.
Save the signage script into /home/pi/digitalsignage.sh and then add the autostart script to /home/pi/.config/autostart/signage.desktop, you might need to make the autostart directory.
The raspberry pi is a nice simple solution as they’re easy to get hold of and has a large community to help you get things perfect, there’s also nice features for display rotation and a host of ways to add hacks, so for instance you could add temperature probes and display the temperature results locally.
