In this format, you can save images that are shot on Sony (Minolta) cameras and some digital SLR cameras. MRW images are stored in uncompressed RAW form, and they contain more detail than compressed images. This format allows you to edit the white balance, exposure, brightness, and other elements losslessly.
PGM is a storage format for grayscale images. Files in this format can be opened using software: ACDSee Photo Manager 14, ACD Systems Canvas 15, Corel PaintShop Pro X4. This type of file can be edited with a text editor. PGM files can be in two versions: P2 / P5. P2 are readable, P5 - to binary formats.