MATLAB File Help: cv.GFTTDetector Index
cv.GFTTDetector

Wrapping class for feature detection using the goodFeaturesToTrack function.

The function finds the most prominent corners in the image or in the specified image region, as described in [Shi94]:

  1. Function calculates the corner quality measure at every source image pixel using the cv.cornerMinEigenVal or cv.cornerHarris.
  2. Function performs a non-maximum suppression (the local maximums in 3x3 neighborhood are retained).
  3. The corners with the minimal eigenvalue less than QualityLevel * max_{x,y}(qualityMeasureMap(x,y)) are rejected.
  4. The remaining corners are sorted by the quality measure in the descending order.
  5. Function throws away each corner for which there is a stronger corner at a distance less than maxDistance.

References:

[Shi94]:

Jianbo Shi and Carlo Tomasi. "Good features to track". In Computer Vision and Pattern Recognition, 1994. Proceedings CVPR'94., 1994 IEEE Computer Society Conference on, pages 593-600. IEEE, 1994.

See also
cv.goodFeaturesToTrack, cv.cornerHarris, cv.cornerMinEigenVal, cv.FeatureDetector
Class Details
Superclasses handle
Sealed false
Construct on load false
Constructor Summary
GFTTDetector Constructor 
Property Summary
BlockSize Size of an average block for computing a derivative covariation 
HarrisDetector Parameter indicating whether to use a Harris detector 
K Free parameter of the Harris detector. 
MaxFeatures Maximum number of corners to return. 
MinDistance Minimum possible Euclidean distance between the returned corners. 
QualityLevel Parameter characterizing the minimal accepted quality of image 
id Object ID 
Method Summary
  addlistener Add listener for event. 
  clear Clears the algorithm state 
  delete Destructor 
  detect Detects keypoints in an image or image set. 
  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)