"EasyBMP is a simple, cross-platform, open source (revised BSD) C++ library designed for easily reading, writing, and modifying Windows bitmap (BMP) image files... The library is oriented towards the novice programmer with little formal experience, but it is sufficiently capable for anybody who desires to do I/O and pixel operations on uncompressed 1, 4, 8, 16, 24, and 32 bpp (bits per pixel) BMP files." Quote from EasyBMP's website.

EasyBMP ported for the O2 is available for download here