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Template matching is not good when your object is rotated or scaled.

features2d methods to extract keypoints

FAST is simple and fast but doesn't keep information about angle of points of interest. SURF and SIFT are slower, but their information about points of interests are bigger (angles). SIFT and SURF allow you to find scale-invariant matches. If you want scale invariant: BRISK, paper brisk

(FAST, STAR, SIFT, SURF, ORB, BRISK,... are supported in OPENCV: FeatureDectectors)


I did (some time ago) something similar to recognize some sheets. The steps are:

  1. Find keypoints of your sheet
  2. Extract descriptors from those keypoints
  3. Find keypoints of your scene image
  4. Extract descriptors from keypoints
  5. Match descriptors by matcher

In order to extract descriptors, see DescriptorExtractors

Match descriptors by matcher: DescriptorMatcher

Here are to good tutorials:

  1. Find a known object
  2. Guide using SURF feature detector

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