There is a new version of this app (with extra features such as photo transition effect) at syno-photo-frame repository.

Synology Photos album full-screen slideshow for Raspberry Pi.

I wrote this code for a DIY digital photo frame project using Raspberry Pi connected to a monitor (runs great on Pi Zero 2). The goal was to fetch photos directly from my Synology NAS over LAN.

Why not use Synology Photos browser client directly? There are two reasons. First, current version of Synology Photos (1.3.3 at the time of writing) does not allow slideshow speed adjustments, and changes photo every 3 or 4 seconds - way too fast for a photo frame. Second, running a full www browser is much more resource demanding than a simple Python app, which matters when using Raspberry Pi, especially in its Zero variant.

Since I am running all of this over local area network at home only, security is not a priority for me. You should take extra steps which are out of scope of this guide if you plan to access your NAS over Internet, or if you're running this setup in an un-trusted LAN (e.g. in an office or a dorm).

1. Create an album in Synology Photos and add photos to it
2. Click "Share" icon in the Album
3. Check "Enable share link" option
4. Set Privacy Settings to "Public - Anyone with the link can view"
5. Do NOT enable Link Protection - support for password protection might get implemented in the future, for now the assumption is that the NAS and Pi are on the same private LAN.
6. Copy the Share Link somewhere - you'll need it when running the slideshow app on Raspberry Pi
7. Click Save

The assumption is that you are starting with a fresh installation of Raspberry Pi OS Lite, network has been set up (so you can access the NAS) and you have command line access to the Pi.

Update the system and install the OS packages needed to run minimal X server:

sudo -- sh -c ' \
apt update && \
apt upgrade -y && \
apt install -y \
	xserver-xorg \
	x11-xserver-utils \
	xinit \
	python3-tk \
	python3-venv \
	menu \
	git'

Python3-TK is used by the app to display images, while python3-venv is needed to build the source code into a stand-alone executable. Git is optional, and only needed if you'll be cloning the repository. Menu is also optional and is there to avoid some errors being written to ~/.xsession-errors.

Clone the repository using git glone, or download the source code zip and extract e.g. to /home/pi/synology-photos-slideshow.

cd into the directory and run

./build_pex.sh

Wait for the build to finish. A new file synology-photos-slideshow.pex has been created.

Display help message:

./synology-photos-slideshow.pex -h

Run the app in X server:

sudo xinit /home/pi/synology-photos-slideshow/synology-photos-slideshow.pex {sharing link to Synology Photos album}

If everything works as expected, press Ctrl-Alt-1 to get back to the console and Ctrl-C to kill the X server.

For proper long-term usage, disabling screen saver, mouse cursor etc. is desired. Create a startup script file, e.g /home/pi/startSlideshow.sh with the following contents (replace SHARING_LINK with link to your album, and optionally adjust the photo-change-interval, here set to 30 seconds):

#!/bin/sh

# Disable any form of screen saver / screen blanking / power management
xset s off
xset s noblank
xset -dpms

# Allow quitting the X server with Ctrl-Alt-Backspace
setxkbmap -option terminate:ctrl_alt_bksp

# Start Synology Photos slideshow app
/home/pi/synology-photos-slideshow/synology-photos-slideshow.pex "SHARING_LINK" --interval 30 > /tmp/synology-photos-slideshow.log 2>&1

The output of the program will be written to /tmp/synology-photos-slideshow.log file.

Try it out with

sudo xinit /home/pi/startSlideshow.sh

Disclaimer: the script is adjusted from one of the many tutorials available online about setting Raspberry Pi in kiosk mode, unfortunately I can no longer find the specific site to give the authors credit they deserve :(.

To start the slideshow automatically when Pi gets booted, enable auto-login using raspi-config and add the following line to /etc/rc.local just before exit 0 (assuming you created the script file as described above):

sudo xinit /home/pi/startSlideshow.sh &

A proper digital photo frame doesn't run 24/7. Shutdown can be scheduled in software only, but for startup you'll need a hardware solution, e.g. for Raspberry Pi Zero I'm using Witty Pi 3 Mini.

If the album is very large, and the startup-shutdown schedule is short, potentially the slideshow might never display some of the later photos in the album. The --random-start option solves the problem by starting the slideshow at randomly picked photo.

For my digital photo frame project I attached a light sensor to Pi's GPIO to adjust monitor's brightness automatically depending on ambient light. TSL2591 is an example of such sensor. Check out my auto-brightness-rpi-tsl2591 project to add automatic brightness control to your digital photo frame.