MATLAB: How to find first white pixel in an image

Question

I have done few process on my image and got stuck here. So far,this is the result that i got: http://s20.postimage.org/5dg34043h/Pra_processing.png. For now, all i need is to find the first white pixel in that image and do some mark on it. We'll start at the bottom right corner of the grid, scan each column of pixels from the bottom going upwards-starting from the rightmost column and proceeding to the left-until we encounter a first white pixel. We'll declare that pixel as our "start" pixel.

Answer 1

[row, column] = find(yourImage, 1, 'last');