GR*

GR* is a set of similar graphics formats for the Atari computers with unknown origin.

Identification
files are 3844 bytes long.

and  files are either 7680, 7682 or 7684 bytes long.

files are 7689 bytes long.

Software

 * RECOIL

Sample files

 * https://telparia.com/fileFormatSamples/image/grStar/