| Class Summary | 
| DescriptorExtractor | Abstract base class for computing descriptors for image keypoints. | 
| DescriptorMatcher | Abstract base class for matching keypoint descriptors. | 
| DMatch | Structure for matching: query descriptor index, train descriptor index, train
 image index and distance between descriptors. | 
| FeatureDetector | Abstract base class for 2D image feature detectors. | 
| Features2d |  | 
| GenericDescriptorMatcher | Abstract interface for extracting and matching a keypoint descriptor. | 
| KeyPoint | Data structure for salient point detectors. |