The creator says that the PEP image format is meant for small, limited colour images and of course it does lossless compression.

▲ gforce_de 2 days ago | parent [-]

Thanks for making that clear. But is it worth the hassle?

PNG decoding seems to be fast enough:

  tree1    - PEP =  0.412 ms PNG = 0.25 ms
  font     - PEP =  0.602 ms PNG = 0.663 ms
  nz_scene - PEP = 32.121 ms PNG = 3.069 ms

Anyway, PEP is interesting!

	▲	fph 6 hours ago \| parent \| next [-]
		It's a lossless format optimized for file size rather than decompression speed; the README seems clear enough. Made by a pixel art game dev, for compressing sprites in pixel art games, so I assume it fits a useful niche.
	▲	msephton a day ago \| parent \| prev [-]
		I don't see any hassle, really. It's just another image format: good for some use cases, bad for others. No one file format is perfect. It was interesting enough for me to give it a couple of hours to implement a cli and add support to my pixel app.