I've looked at Raspberry Pi's a few times in the past, but never had an opportunity to do something meaningful with them until recently when I was contracted for a project to streamline some processes for a business.
This business has popup studios that travel from one shopping centre to another. They needed an alternative solution for their display TV and music
Their initial TV solution involved a USB stick that needed to be jiggled everytime the TV was turned on, and navigating the TV set to show images from the USB stick in a slideshow, and the music played from a portable ipod like device to a bluetooth speaker. Both devices needed regular recharging.
The goal was to make it easy for staff to use and be able to update the slideshow images and music from head office
After some research I ended up using a Raspberry Pi 3 Model B as the source for the slideshow and music. The RPi has an HDMI interface which plugs directly into the TV and has an 3.5mm audio out jack that can connect to an amplifier which has speakers hooked up. The amp has volume control so the volume can be adjusted if needed. With everything hardwired, there's nothing for staff to do but flip the powerswitch.
Using standard Raspbian (which is debian based), I used an app called 'feh' to drive the slideshow, which is automatically started when the RPi boots. It's configured to loop through images in a folder.
Using an app called 'mpg321' I did the same for the music.
I also replaced the Raspbian splash screen with a company logo to make it look more professional.
In order to update both slideshow images and music, I installed Syncthing both on the RPi and at head office on their Synology NAS. Now all it needs is an internet connection (Part 2).
Cost (without TV) came to $55 for the RPi, $15 for a micro SD Card, $10 for a case, $15 for a PSU, $50 for speakers and $30 for an amp. Total $175 per studio.