Find out the first while pixel from right side ?

I have done few process on my image and got stuck here. So far,this is the result that i got For now, all i need is to find the first white pixel in that image at every column from right side and display only that pixel rest all pixel in same row to be black .

Answer 1

[Matt J]

   [m,n]=size(yourImage);
  [~,idx]=max(fliplr(yourImage),[],2);

newImage=  ( (n+1-idx)==(1:n) );

[Sobit Singh]

Sir can you help me a little further i have to now find the distance between these two lines my approach is to add the two images and no of black pixel between white pixel from same row would be my distance . But i am not able to code my idea..

Answer 2

[Guillaume]

The index of the maximum of each row of a binary image is also the index of the first white pixel of each row, thus:

newimage = false(size(yourimage));  %create blank binary image. 
[~, col] = max(yourimage, [], 2);    %find coordinate of 1st pixel of each row  
newimage(ind2sub(size(newimage), (1:size(newimage, 1))', col)) = true;