(Please see my comment to the question.) Sorry if my references are way too redundant, but Wikipedia provides some description and references:
http://en.wikipedia.org/wiki/Image_moment[
^].
Only one referenced publication apparently should provide source code, but that's Python and Matlab. To me, the quality of code would be much more important than a language, to re-implement or translate algorithm is easier. Please see:
http://www.dacya.ucm.es/jam/computer_vision.html[
^].
I'm pretty sure you will be able to find some more, but not sure you can find something really useful. Many topic like that are not readily available on the Web.
—SA