GAB - Bitmap Image File Format
GAB files contain bitmapped image data. Each file has a fixed header, followed by pixel data, followed by a CRC32 for the entire file up to the CRC.
Pixel data is oriented such that (0, 0) is the lower left corner of image and (1, 1) is the upper right corer of image. This is how OpenGL expects pixel data to be oriented, but is contrary to most image formats.
|Fixed Header||16 bytes|
|Pixel Data||Variable size. Width * Height * pixel size.|
|CRC32||4 bytes. CRC32 is computed for entire file except for this 4 byte section.|
Fixed Header Details
|4||LE Signature: 0x1a42414d ("GAB\x1a")|
|1||File format version number. Currently should always be 1.|
|2||Width in pixels (unsigned short)|
|2||Height in pixels (unsigned short)|
|6||Reserved for future use|