Find out which blob has the pixel location [x,y]?

I have a labelled blob image using bwlabel, I want to find a blob which has the pixel location [x,y] and display it by removing the rest of blobs. Here is the code I wrote, but it doesn't give correct answer, please fix this

[y, x] = ginput(1);
x = round(x);
y = round(y); % here x and y is a location of blob i want to keep

      BW = bwlabel(newImgg,4) ; % labelled image contains several blobs
  %     figure, imshow(BW, [])
      props = regionprops(logical(BW),'all');
      while(1)
          for k = 2:length(props)
              if isequal(ismember([x,y],props(k,1).PixelList),[1, 1]);
                  keeperIndex = k;
                  break
              end
          end
          break
      end

      keeperBlobsImage = ismember(BW, keeperIndex);
      keeperBlobsImage = imfill(keeperBlobsImage,'holes');
      figure, imshow(keeperBlobsImage,[])

Thanks,

Gopi

Answer 1

[Walter Roberson]

BW(y, x) is the blob number when BW is the result of bwlabel(). And you can then proceed to get rid of everything else using the mask BW == BW(y, x)

Note that y is first and then x in indexing.

[Gopichandh Danala]

Sorry for the wrong explanation, in the above code I get x,y coordinates from the original image and not the labelled image, now after getting labels I want to find blob which has that given ,x,y coordinates

[Walter Roberson]

What difference is there between coordinates in the original image and coordinates in the labeled image? Are they not the same number of rows and columns?

[Gopichandh Danala]

The number of rows and columns in both original and labeled image are same, But I get [x,y] a pixel coordinate from the original image and the labels are obtained at a later stage, now I want to select the blob which has the corresponding blob. For this, i don't blob label which belongs to coordinate.

[Gopichandh Danala]

The problem I found in my code is that

if isequal(ismember([x,y],props(k,1).PixelList),[1, 1]);

This statement in the above code is looking for all x coordinates in props(k,1).PixelList) separately and all y coordinates in props(k,1).PixelList) separately and if both those x and y occur anywhere in x and y column it chooses that blob as the keerBlolb

[Gopichandh Danala]

I understood what you tried to say, It worked Thanks