title: Detecting blobs of uniform colour with openCV
body: <p>I am working on a program to detect split fields for remote sensing (ie. more than one colour/field type within each image, where the image corresponds to the land owned by one farmer)  and have been trying to find a solution by reading in images and posterizing them with a clustering algorithm, then analysing the colours and shapes present to try and 'score' each image and decide if more than one type of field is present. My program works reasonably well although there are still quite a few obvious splits that it fails to detect.</p>
  
  <p>Up until now I have been doing this using only standard libraries in c++, but I think now that I should be using openCV or something and I was wondering which techniques to start with. I see there are some image segmentation and blob detection algorithms, but I'm not sure they are applicable because the boundary between fields tends to be blurred or low in contrast. The following are some sample images that I would expect my program to detect as 'split':</p>
  
  <p>(True colour Landsat)</p>
  
  <p><a href="https://imgur.com/m9qWBcq" rel="nofollow noreferrer">http://imgur.com/m9qWBcq</a></p>
  
  <p><img src="https://i.stack.imgur.com/pEb9X.png" alt="enter image description here"></p>
  
  <p><a href="https://imgur.com/OwqvUvs" rel="nofollow noreferrer">http://imgur.com/OwqvUvs</a></p>
  
  <p><img src="https://i.stack.imgur.com/pA1dp.png" alt="enter image description here"></p>
  
  <p>Are there any thoughts on how I could go about solving this problem in a different way? Thanks!</p>