Are there ASCII-only image files?

I need some sample image data that consists of ASCII characters only, with a license suitable for commercial use (in documentation).

Data should ideally be printable and unambiguous (i.e. no control chars, no tab, but space 0x20 would be ok).

Do you have any or know of any links?

Can be JPEG, PNG, GIF, BMP, TIF.

Something similar to the EICAR antivirus test file that is a valid executable made up of printable ASCII characters only.