Code Troubleshooting for replacing pixels in original image and ending with "index exceeds matrix dimensions."

My image size is 1600x1200 and I'm wondering why it keeps saying "index exceeds matrix dimensions." I want to fill the parts within the yellow triangle and red circles with gray. My image is attached.

I=imread('image2-1.jpg');
Ired=I(:,:,1);
imgray=rgb2gray(I);
BW1 = im2bw(Ired,0.9);
BW1=imfill(BW1,'holes');
figure,imshow(BW1);
c = 1;
I3 = zeros(1600, 1200);
while c <= 1600
 d = 1;
 while d <= 1200
      I3(c, d) = BW1(c, d);
      d = d+1;
      if BW1(c,d)>0
          I(c,d,1)=127;
          I(c,d,2)=127;
          I(c,d,3)=127;
      end
 end
  c = c+1;
end
figure, imshow(I);

Answer 1

[Gopichandh Danala]

I checked the attached image: It is not 1600 * 1200

>> I=imread('image2-1.jpg');
>> size(I)

ans =

     385   513     3

I resized the image just in case if attaced image is wrong:

I = imresize(I, [1600 1200], 'bilinear');

>> size(I)

ans =

          1600        1200           3

Your d-value in the while loop has to be at the end of the inner while loop:

while c <= 1600
 d = 1;
 while d <= 1200
      I3(c, d) = BW1(c, d);
      if BW1(c,d)>0
          I(c,d,1)=127;
          I(c,d,2)=127;
          I(c,d,3)=127;
      end
      d = d+1;
 end
  c = c+1;
end

But I found few problems in the code..

>> max(BW1(:))

ans =

    logical

     0

so, there are no values in the BW1 so your ' if condition' is never true and 'I' values doesn't get updated.

check your code where you are computing BW1 where you are expecting to find the marked regions

[Megan Wang]

Yeah I actually figured it out a few hours ago but you were right in that the "d = d+1" part was in the wrong place. Thanks!

[Gopichandh Danala]

no problem, just think about your BW1 image too