I am starting to work with Pd and I want to do something with video editing. But I still cannot find a way for Pd to recognise my camera, when I try to work with a video patch, it just shows a white image. 

Can you please help me solve this problem? 

I have a Mac OS X Version 10.9.5
My version of Pd is: Pd 0.43.4-extended
And I'm working with the Mac's built in camera.

Thank you very much,
Olga Isabel Medina Nieto 
https://www.youtube.com/user/efiLsIcisuM
https://www.facebook.com/olguitarmedina