Specifications

Image Filtering
6-13
6
IPL_SOBEL_3x3_H A gradient filter (horizontal Sobel operator).
This filter uses the kernel
121
000
-1 -2 -1
IPL_LAPLACIAN_3x3
A3x3 Laplacian highpass filter.
This filter uses the kernel
-1 -1 -1
-1 8 -1
-1 -1 -1
IPL_LAPLACIAN_5x5 A5x5 Laplacian highpass filter.
This filter uses the kernel
-1 -3 -4 -3 -1
-3060-3
-4 6 20 6 -4
-3060-3
-1 -3 -4 -3 -1
IPL_GAUSSIAN_3x3
A3x3 Gaussian lowpass filter.
This filter uses the kernel
A /16,where
121
A =242
121
These filter coefficients correspond to a 2-dimensional Gaussian
distribution with standard deviation 0.85.
IPL_GAUSSIAN_5x5 A5x5 Gaussian lowpass filter.
This filter uses the kernel
A /571,where
271272
731 5231 7
A = 12 52 127 52 12
731 5231 7
271272