Average/Mean Filter

in that case i would start searching around for 2d convolution HDL, and if there isn't much out there start looking for matlab or c code and porting to HDL.

i am not sure averaging over each r, g, and b is going to give the best results. you might want to compare converting from RGB to HSI and filtering the h, s, and i components or just the i component (and converting back to RGB) to filtering the individual RGB channels using matlab or c.