The format has a TIFF-image structure. It is generated by Canon cameras. The CR2 photo is stored in an uncompressed form and allows you to edit such settings as white balance, exposure, and other settings for photos that were already taken. It is the successor format to CRW, which was used in previous generation Canon SLR cameras.
A bitmap image in the Portable Any Map format that was originally developed for processing and storing several types of monochrome and color images without compression as well as grayscale images. Bitmap graphics data in a PNM file are stored using ASCII or binary structure.