Contains classes for 2D feature detection, extraction and matching.


Public classBOWImgDescriptorExtractor<(Of <(<'T>)>)>
Class to compute an image descriptor using the bag of visual words. Such a computation consists of the following steps: 1. Compute descriptors for a given image and its keypoints set. 2. Find the nearest visual words from the vocabulary for each keypoint descriptor. 3. Compute the bag-of-words image descriptor as is a normalized histogram of vocabulary words encountered in the image. The i-th bin of the histogram is a frequency of i-th word of the vocabulary in the given image.
Public classBOWKMeansTrainer
Kmeans-based class to train visual vocabulary using the bag of visual words approach.
Public classBriefDescriptorExtractor
BRIEF Descriptor
Public classBrisk
BRISK: Binary Robust Invariant Scalable Keypoints
Public classBruteForceMatcher<(Of <(<'T>)>)>
Wrapped BruteForceMatcher
Public classDenseFeatureDetector
Class for generation of image features which are distributed densely and regularly over the image.
Public classDescriptorMatcher<(Of <(<'T>)>)>
Descriptor matcher
Public classFastDetector
FAST(Features from Accelerated Segment Test) keypoint detector. See Detects corners using FAST algorithm by E. Rosten (”Machine learning for high-speed corner detection”, 2006).
Public classFeature2DBase<(Of <(<'TDescriptor>)>)>
The feature 2D base class
Public classFeatures2DExtensions
A collection of Extension methods for IKeyPointDetector
Public classFeatures2DToolbox
Tools for features 2D
Public classFeatures2DTracker<(Of <(<'TDescriptor>)>)>
This class use ImageFeature to match or track object
Public classFreak
The FREAK (Fast Retina Keypoint) keypoint descriptor: Alahi, R. Ortiz, and P. Vandergheynst. FREAK: Fast Retina Keypoint. In IEEE Conference on Computer Vision and Pattern Recognition, 2012. CVPR 2012 Open Source Award Winner. The algorithm propose a novel keypoint descriptor inspired by the human visual system and more precisely the retina, coined Fast Retina Key- point (FREAK). A cascade of binary strings is computed by efficiently comparing image intensities over a retinal sampling pattern. FREAKs are in general faster to compute with lower memory load and also more robust than SIFT, SURF or BRISK. They are competitive alternatives to existing keypoints in particular for embedded applications.
Public classGFTTDetector
Wrapping class for feature detection using the goodFeaturesToTrack() function.
Public classGridAdaptedFeatureDetector
Adapts a detector to partition the source image into a grid and detect points in each cell.
Public classMSERDetector
Wrapped CvMSERParams structure
Public classOpponentColorDescriptorExtractor<(Of <(<'TDescriptor>)>)>
Class adapting a descriptor extractor to compute descriptors in the Opponent Color Space (refer to Van de Sande et al., CGIV 2008 Color Descriptors for Object Category Recognition). Input RGB image is transformed in the Opponent Color Space. Then, an unadapted descriptor extractor (set in the constructor) computes descriptors on each of three channels and concatenates them into a single color descriptor.
Public classORBDetector
Wrapped ORB detector
Public classPlanarObjectDetector
A Planar object detector
Public classRTreeClassifier<(Of <(<'TColor>)>)>
The Calonder classifier
Public classSelfSimDescriptor
Public classSIFTDetector
Wrapped SIFT detector
Public classStarDetector
Public classSURFDetector
Wrapped CvSURFParams structure
Public classSURFFeature
A SURF feature


Public structureFeatures2DTracker<(Of <(<'TDescriptor>)>)>..::..MatchedImageFeature
The matched Image feature
Public structureFeatures2DTracker<(Of <(<'TDescriptor>)>)>..::..SimilarFeature
A similar feature is a structure that contains a Image feature and its corresponding distance to the comparing Image feature
Public structureImageFeature<(Of <(<'TDescriptor>)>)>
An ImageFeature contains a keypoint and its descriptor
Public structureLDetector
V. Lepetit keypoint detector
Public structurePatchGenerator
OpenCV's PatchGenerator


Public interfaceIDescriptorExtractor<(Of <(<'TColor, TDescriptor>)>)>
An interface for a descriptor generator
Public interfaceIKeyPointDetector
An interface for keypoint detector


Public enumerationDistanceType
The match distance type
Public enumerationFeatures2DToolbox..::..KeypointDrawType
Define the Keypoint draw type
Public enumerationORBDetector..::..ScoreType
The score type