A simple Arduino program to cycle through images over SPI on an ESP32 microcontroller. Uses an E-paper display and ESP32 E-paper driver board from Waveshare. This project will only work with this board as it uses libraries from Waveshare to function. Based on a modified example from Waveshare. Also includes a JPEG to HEX converter specifically for this product line. Converter was not made by me, credit goes to WhiteRabbit.
This will likely only work with the board I am using.
Applying dithering and re-scaling or use didder
Didder example command (B/W) didder -i "*.jpg" -o "M:\Media\Downloads" --palette "black white" --recolor "black white" -x 648 -y 480 -s 80% -g edm --serpentine FloydSteinberg
This requires Adobe Photoshop. Other imaging editing tools will probably work, it's just what I used. All it's needed for is to change the resolution to your screen size and set the colour table for dithering purposes.
Go to the Colour Table folder included, Colour Tables -> (Choose the one most suitable for your display)
In the Options folder, edit the default.json file to fit your screen (notepad will do for this). you should only need to do this once.
If there is an error check picture file name is picture.jpeg
, or ask around.