MATLAB File Help: cv.ORB Index
cv.ORB

Class implementing the ORB (oriented BRIEF) keypoint detector and descriptor extractor.

As described in [RRKB11]. The algorithm uses FAST in pyramids to detect stable keypoints, selects the strongest features using FAST or Harris response, finds their orientation using first-order moments and computes the descriptors using BRIEF (where the coordinates of random point pairs (or k-tuples) are rotated according to the measured orientation).

References:

[RRKB11]:

Ethan Rublee, Vincent Rabaud, Kurt Konolige, and Gary Bradski. "ORB: An efficient alternative to SIFT or SURF". In IEEE International Conference on Computer Vision (ICCV) 2011, pages 2564-2571. IEEE, 2011.

See also
cv.FeatureDetector, cv.DescriptorExtractor
Class Details
Superclasses handle
Sealed false
Construct on load false
Constructor Summary
ORB The ORB constructor. 
Property Summary
EdgeThreshold This is size of the border where the features are not detected. 
FastThreshold Threshold on difference between intensity of the central pixel 
FirstLevel It should be 0 in the current implementation. 
MaxFeatures The maximum number of features to retain. 
NLevels The number of pyramid levels. 
PatchSize Size of the patch used by the oriented BRIEF descriptor. 
ScaleFactor Pyramid decimation ratio. 
ScoreType Algorithm used to rank features. 
WTA_K The number of points that produce each element of the oriented BRIEF 
id Object ID 
Method Summary
  addlistener Add listener for event. 
  clear Clears the algorithm state 
  compute Computes the descriptors for a set of keypoints detected in an image or image set. 
  defaultNorm Returns the default norm type 
  delete Destructor 
  descriptorSize Returns the descriptor size in bytes 
  descriptorType Returns the descriptor type 
  detect Detects keypoints in an image or image set. 
  detectAndCompute Finds keypoints in an image and computes their descriptors 
  empty Checks if detector object is empty. 
  eq == (EQ) Test handle equality. 
  findobj Find objects matching specified conditions. 
  findprop Find property of MATLAB handle object. 
  ge >= (GE) Greater than or equal relation for handles. 
  getDefaultName Returns the algorithm string identifier 
  gt > (GT) Greater than relation for handles. 
Sealed   isvalid Test handle validity. 
  le <= (LE) Less than or equal relation for handles. 
  load Loads algorithm from a file or a string 
  lt < (LT) Less than relation for handles. 
  ne ~= (NE) Not equal relation for handles. 
  notify Notify listeners of event. 
  save Saves the algorithm parameters to a file 
  typeid Name of the C++ type (RTTI)