[File format] .Piskel files

[BeansBeefBroccoli]

Describe the file format
.piskel files are a json-based pixel art files. They come from Piskel.

Describe the expected behavior
As on the website, they should be able to be converted into animated GIFs, PNGs, ZIP archives containing one PNG for each frame, and C files. Below are screenshots showing export options in Piskel:

Provide reference implementations
https://www.piskelapp.com/

Do you plan on implementing this yourself?
No

Additional context
Some example Piskel files

[ConnorTippets]

idk if linking the app counts as reference implementation for the file format but sure