Would like to see support for other image sizes

[magicbycalvin]

It would be beneficial to people using this library for image processing if it supported different bit depths and structures. For the time being, I have modified the code so that I can use it on 24 bit images. Supporting a single channel, RGB, and RGBA would offer a lot of functionality for users. Additionally, in scientific processes, such as spectroscopy, images can be comprised of higher bit depths such as 16 bits for a single pixel in a single channel. Thank you for considering this change!