title: Open CV Features Extraction and Image Matching
body: <p>I want to develop an automatic image annotator and an image search application. I have tried using Color Histogram from Open CV's tutorials. It is not giving good results . I used Color Histogram so that I can easily distinguish between night scene or a day scene .</p>
  
  <p>I also want to incorporate shape and texture features for matching images . I did not find anything for extracting shape and texture features from images using Open CV .Please let me know how to extract these features using Open CV or if there is any other library that can hep me in extraction of these features .</p>
  
  <p>I have tried SURF features but for dissimilar images they are not giving good matches .Like two images of Horse in completely different context .</p>
  
  <p>I have a training set of 15K annotated images from the Mir Flick Data Sets and I have a set of around 100 tags . I have read many research papers that give the theoretical approach to this problem but I am unable to implement it. </p>
  
  <p>Thanks in advance .</p>