tracking pixels

I have a matrix, where pixels change. Active state is white, inactive is black. I want to output a list of the active pixels, so the coordinates of every pixel. Then I want these pixels to be connected to a pitch. the jit.iter is almost what I want but I only get the last pixel (ok, the rest to, but I can't put them in a list).
In short, my matrix is connected to jit.iter and that is connected to the unpacks. However, how can I make a decent list of the active pixels that is easy to read?