I’ve recently opened up a backup of my modded Minecraft servers and looked around in the OpenComputers directory, and found some old image formats made by Rph.
SIF stands for Simple Image Format. It was made somewhere around early 2019. SIF pictures only support 160x50 (the native OpenComputers resolution) and 240 colors. The 16 user-definable colors are unused. It was very slow, and images were really chunky. It was however a success.
You can find the various utilities for both SIF and SIF2 at the SIF archive on this site
SIF was generally identical to SIF, but had its colors obfuscated to prevent reverse engineering. Other than that, there is no difference.
PRIF was really an experiment only. Rph doesn’t even remember what it stands for, as it was really short-lived. Instead of using regular pixels, PRIF would use UTF-8 half blocks to get twice as tall rendering. I only found one decoder for it, and it wasn’t really useful as there’s no encoder for it, not even a single file that you could use with it.
SIF3 was the next evolution of SIF, using Unicode Braille characters to get 320x200 picture rendering, and 256 colors when rendering with OpenComputers. Technically, SIF3 did not have a color limit as colors were not simplified so 24-bit images could be produced. SIF3 hasn’t been uploaded to the SIF archive yet, this page will be updated when I do so.
FIF is the Fast Image Format, recently open-sourced by Rph. It supports very fast rendering of images, and can compress images by simplifying colors and actually being a bytecode format. You can get the encoder here and OpenOS viewer here.
With FIF having near instant image rendering thanks to buffers (and now even video!), a lot of OpenComputers applications can now become a reality.
It was fun seeing how each next generation brought more features, speed and higher resolution.