LCD logo HELP!! - PCD8544 controller nokia 3310

please can anyone tell me if there is a simple program for generating images to the ascii code?? I bought the lcd shield and want to change the AVR Logo with one made from me. But i dont know how to make it to ascii. I dont want to do it manually cause its a waste of time.

And if it's possible to be able to convert any image of any dimension to the asci code...