I wrote a little tool, that converts 128x128 .png images to native .p8 code. It does not import the image to mapdata, (like https://www.lexaloffle.com/bbs/?tid=2715), but converts it to native code.

https://github.com/nodepond/pic2pico/

Currently only exact matching colors are transfered into code.

This tool might be useful, if you want a background, but also have sprites for i.e. displaying text. Of of the next features might be some compressing of image data, to show even more images.

Made a small update:

Colors are converted now with a little bit of color-tolerance. Some (pixel)-editors do not use the 100% exact pico-8 colors, so now converting into .p8 is got a little bit more failsave.

It's available here: https://github.com/nodepond/pic2pico/

This looks great. I always wondered if we can use a png as a background image. I'm a bit of a coding noob. Would you be able to write a dummies guide, or maybe a video on how to use this, with an example image??