This instruction is a quick translation for an instruction in Russian available at

http://privateblog.info/arduino-due-i-kamera-ov7670-primer-ispolzovaniya/

Connection of OV7670 to Arduino Due is easier than to Arduino Uno: lower operation voltage – only 3V, higher internal speed, more memory and more contacts on the board.

Source: How to Connect OV7670 to Arduino Due: 6 Steps (with Pictures)