How to convert .img files to .png format.
Converting GEM Images directly to Portable Network Graphics (.img to .png conversion) is certainly possible and can be done using a graphics editing software or (online) conversion tool.
Try using, for instance, XnConvert, which allows users to import .img images and re-save them as .png graphics.
Alternatively, you can try Logipole Konvertor, as this tool also supports the .img format.
Konvertor is a fast and reliable two-panel file converter for Windows.
A cross-platform batch image transcoder compatible with 500 picture image formats
A popular utility for viewing and converting graphic files