A micro-controller is not suitable to do image processing.
Depending on the kind of image processing you want to do, you might need to have the complete image uncompressed in memory.
If we suppose your camera is configured for VGA, 8bits per pixels (greyscale) that's already 640*480 / 1024 = 300 kbytes
I am not familiar with PIC, but I doubt you will find a micro-controller with that amount of RAM...
One possibility it to program your cell phone to do the processing. What type of cell phone is it?