help for vhdl processing image

thanks FvM for your information,but for example, when I have to first to stock image in the ram, second read cases of this ram, third modify this pixel finally to write it in an other place of ram, how to access for the cases of the ram if i can't use for loop,how to paralleled the code if it is sequential, I know that is using FSM but it still sequential, can you clear more really I need every advice and idea to achieve my project and really I will be thankful.