Viewing images · wolf@nereid.pl

submited by

Style Pass

2025-01-12 18:30:17

How hard would it be to display the contents of an image file on the screen? You just load the image pixels somehow, perhaps using a readily available library, and then display those pixels on the screen. Easy, right? Well, not quite, as it turns out.

I may have some experience with this,1 because I made an image viewer that displays images in the terminal emulator. But why do such a thing, there are countless image viewers already available, including those that work with terminal emulators, why write yet another one? That’s an excellent question! As always2, the answer is because no other viewer was good enough for me.

For example, catimg uses stb_image to load images. While stb_image is an outstanding library that can be integrated very quickly, it doesn’t really excel in the number of image formats it supports. There’s the baseline of JPEG, PNG, GIF, plus a few other more or less obscure formats.

Another example is viu, which again is limited to the well-known baseline of three “web” formats, with the modern addition of WebP. Following the dependency graph of the program shows that the image loading library it uses should support more formats, but ultimately I’m interested in what the executable I have on my system can do, not what some readme says.