How can I mark a defects with lines in a image?

Hey everyone! I already asked something about this question but I deleted it because I don't have that problem anymore about that.Anyways,

I detected a defect (scratch) in my image and I want to show detected scratch on the original image and to this I want to mark it with lines (red lines or whatever).Maybe I can use regionprops but I don't know how to do. Finally if you manage to solve my question with a code, please add it to my main code.They should be only a code.

The attached is image and Gradients function.

Code:

im1 = imresize(imread('5817292-5_yellow_WRL.bmp'),0.5);
gSize = 15;
im1 = imfilter(im1,fspecial('gaussian',[gSize,gSize],gSize/2),'replicate');
[~,~,mag,~] = Gradients(im1);
imshow(mag);
mgBw = mag > 0.5*max(mag(:));
imshow(mgBw);
mgBw1 = imclose(mgBw,strel('disk',1));
imshow(mgBw1);
mgBw2 = bwareaopen(mgBw1,500);
imshow(mgBw2);
mgBw3 = imclose(mgBw2,strel('disk',2));
imshow(mgBw3);
mgBw4 = imfill(mgBw3,'holes');
imshow(mgBw4);

Answer 1

[Image Analyst]

Hopefully you deleted your prior question before anyone commented on it or answered it. People don't take kindly to that. People also like it if you vote for or Accept their answers to give them "reputation points" for helping you.

Try imoverlay()

rgbImage = imoverlay(im1, mgBw4);
imshow(rgbImage);

I'd also suggest you take a look at applying stdfilt() to your image and then thresholding to find the scratches.

[Ayberk Ay]

I couldn't delete my prior question because there is no deleting options for that question but at least I accepted the answer.

Also thanks so much for this solution, I tried imoverlay() and the result is really good.

I'll try stdfilt() and then thresholding also, thanks again!