title: How to group and highlight group of pixels in an image using OpenCV?
body: <p>During the process of error level analysis on an image, I want to highlight the pixel changes using OpenCV(With just a single image and not the difference). I know the pixel-level values for the output image but not sure about the methods to group them together and assign a shape to that (Example below where the pixel change is specified with a shape). I want to know if I could detect the circle with the lighter pixels and group them and add a grouped shape for the pixels</p>
  
  <p>Input Image: </p>
  
  <p><a href="https://i.stack.imgur.com/fOTmh.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/fOTmh.jpg" alt="enter image description here"></a></p>
  
  <p>Result Image: </p>
  
  <p><a href="https://i.stack.imgur.com/J6Srx.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/J6Srx.jpg" alt="enter image description here"></a></p>