to draw rectangle containing motion region

I have an image having black background and motion region that is detected is in white color. I want a matlab code to draw the rectangle over image containing all the motion regions. I have tried following code but it is giving wrong output. Plz help me with the code.. {

   %for loop to get d first pixel of image having value 255
 d=1;
        for x=1:1:r
            for y=1:1:c
                if fd1(x,y)==255 %fd1 is image whose pixels we are checking
                   as1=x;
                   bs1=y;
                   d=0;
                 break;   
                end
                if (d==0)
                    break;
                end
            end
             end
        }  
    %reverse for loop to get d last pixel of image having value 255
    d=1;
    for x=r:-1:1
        for y=c:-1:1
            if fd1(x,y)==255
               ae1=x;
               be1=y;
               d=0; 
               break;
            end
            if(d==0)
                break;
            end
        end
       end
           w=as1-ae1;
           h=be1-bs1;
     rectangle('Position',[as1,bs1,w,h],'EdgeColor','g','LineWidth',2)
    }

[David Young]

Please could you format the code so it is readable. You can edit your question to do this. Paste the code in again, select it, then click on the {}Code button. Alternatively, indent each line of code by at least two spaces.

[Ashish Uthama]

+1 on the code format. From your comments, I would suggest looking at the FIND function to replace your loops.

What is 'wrong' about the output?

[Karan Ratnaparkhi]

using above the rectangle which i am getting is nt right

Answer 1

[David Young]

I think your problem may be the classic row/column vs x/y confusion.

In an image, the first index (row index) corresponds to the y coordinate in functions like PLOT and RECTANGLE. The second index (column index) corresponds to the x coordinate.

There are various possible ways to change your code, but I'd suggest this one. Change the first two lines of the loops to this:

for y=1:1:r
   for x=1:1:c

and this:

for y=r:-1:1
  for x=c:-1:1

Don't change anything else! See if that helps. (I'm assuming that you are drawing the rectangle in the same axes as the image - for example by displaying the image then using HOLD ON.)

[Karan Ratnaparkhi]

hey David my prblm ws dat nly bt finally i gt it. Thnx for ur help.