Hi. I have an image I (greyscale). I detected and extracted SURF features from this image :
poi = detectSURFFeatures(I);
[features,validPoi] = extractFeatures(I,poi,'SURFSize',128);
373 features have been found. However, when I count the number of features matching to themselves, not all features match:
indexPairs = matchFeatures(features,features);
index pairs returns 365 matches only. Why ??? Note that I found this results for one image out of three only. For the other two images, matchFeatures returns the same number of features as extractFeatures. Thanks !