Here I made a program that compresses an png to a smaller file. Instead of saving the color for each individual pixel I save a reference to a specific color in my color references tab. View the video to see the exact file structure.
There are already a lot of great image compression programs out there, though I thought it was very educational to write such a tool myself. The principle i used to compress the image can be used in a lot of different situations too.
This was programmed in C#.
More info on davidschep.com - June 25, 2016