Thank you for your reply.
We haven't found people who had a similar project and we don't find answers to some basic questions we ask.
First, we succeeded to flash an LED thanks to Arduino (which, in view our level computer, was a feat in our eyes
But when connecting the CMUCAM4 in Arduino, we had a doubt : should power the CMUCAM4 or simply plugging with Arduino is enough?
Thanks a lot, Thymiane & Laetitia.