Harris corner detector.
More...

AFAPI features  harris (const array &in, const unsigned max_corners=500, const float min_response=1e5f, const float sigma=1.f, const unsigned block_size=0, const float k_thr=0.04f) 
 C++ Interface for Harris corner detector. More...


AFAPI af_err  af_harris (af_features *out, const af_array in, const unsigned max_corners, const float min_response, const float sigma, const unsigned block_size, const float k_thr) 
 C Interface for Harris corner detector. More...


Harris corner detector.
Compute corners using the Harris corner detector approach. For each pixel, a small window is used to calculate the determinant and trace of such a window, from which a response is calculated. Pixels are considered corners if they are local maximas and have a high positive response.
◆ af_harris()
AFAPI af_err af_harris 
( 
af_features * 
out, 


const af_array 
in, 


const unsigned 
max_corners, 


const float 
min_response, 


const float 
sigma, 


const unsigned 
block_size, 


const float 
k_thr 

) 
 
C Interface for Harris corner detector.
 Parameters

[out]  out  struct containing arrays for x and y coordinates and score (Harris response), while arrays orientation and size are set to 0 and 1, respectively, because Harris does not compute that information 
[in]  in  array containing a grayscale image (color images are not supported) 
[in]  max_corners  maximum number of corners to keep, only retains those with highest Harris responses 
[in]  min_response  minimum response in order for a corner to be retained, only used if max_corners = 0 
[in]  sigma  the standard deviation of a circular window (its dimensions will be calculated according to the standard deviation), the covariation matrix will be calculated to a circular neighborhood of this standard deviation (only used when block_size == 0, must be >= 0.5f and <= 5.0f) 
[in]  block_size  square window size, the covariation matrix will be calculated to a square neighborhood of this size (must be >= 3 and <= 31) 
[in]  k_thr  Harris constant, usually set empirically to 0.04f (must be >= 0.01f) 
◆ harris()
AFAPI features af::harris 
( 
const array & 
in, 


const unsigned 
max_corners = 500 , 


const float 
min_response = 1e5f , 


const float 
sigma = 1.f , 


const unsigned 
block_size = 0 , 


const float 
k_thr = 0.04f 

) 
 
C++ Interface for Harris corner detector.
 Parameters

[in]  in  array containing a grayscale image (color images are not supported) 
[in]  max_corners  maximum number of corners to keep, only retains those with highest Harris responses 
[in]  min_response  minimum response in order for a corner to be retained, only used if max_corners = 0 
[in]  sigma  the standard deviation of a circular window (its dimensions will be calculated according to the standard deviation), the covariation matrix will be calculated to a circular neighborhood of this standard deviation (only used when block_size == 0, must be >= 0.5f and <= 5.0f) 
[in]  block_size  square window size, the covariation matrix will be calculated to a square neighborhood of this size (must be >= 3 and <= 31) 
[in]  k_thr  Harris constant, usually set empirically to 0.04f (must be >= 0.01f) 
 Returns
 features object containing arrays for x and y coordinates and score (Harris response), while arrays orientation and size are set to 0 and 1, respectively, because Harris does not compute that information