Feature Detection Functions

This section describes feature detection functions.

The set of the Sobel derivative filters is generally used to find edges, ridges, and blobs, especially in case of scale-space images, for example, pyramids.

The following naming conventions are used in the equations described below:

• D_x and D_y are the first x and y derivatives, respectively.
• D_xx are D_yy are the second x and y derivatives, respectively.
• D_xy is the partial x and y derivative.
• D_xxx and D_yyy are the third x and y derivatives, respectively.
• D_xxy and D_xyy are the third partial x and y derivatives.

• Corner Detection
  
• FastNGetSize
  Computes the size of the FastN context structure.
• FastNGetBufferSize
  Computes the size of the work buffer for the FastN function.
• FastNInit
  Initializes the FastN context structure.
• FastN
  Detects corners in an image using the FastN algorithm.
• FastN2DToVec
  Converts corners from two-dimensional image to an array of structures.
• HarrisCornerGetBufferSize
  Calculates the size of the temporary buffer for the ippiHarrisCorner function.
• HarrisCorner
  Implements Harris corner detection algorithm.
• Canny Edge Detector
  
• Histogram of Oriented Gradients (HOG) Descriptor
  
• Hough Transform
  
• LineSuppressionGetBufferSize
  Computes the size of the external buffer for the ippiLineSuppression function.
• LineSuppression
  Implements the line suppression algorithm.