Second order derivative filter
#include "dip_derivatives.h"
dip_Error dip_LaplacePlusDgg ( in, out, boundary, ps, sigmas, tc, flavour )
Depends on the underlying implementation, but expect:
binary, integer, float
Computes the laplace and the second derivative in gradient direction of an image using the Derivative function and adds the results. The zero-crossings of the result correspond to the edges in the image, just as for the individual Laplace and Dgg operators. The localization is improved by an order of magnitude with respect to the individual operators.
| Data type | Name | Description |
| dip_Image | in | Input |
| dip_Image | out | Output |
| dip_BoundaryArray | boundary | Boundary conditions |
| dip_BooleanArray | ps | Dimensions to process |
| dip_FloatArray | sigmas | Sigma of Gaussian |
| dip_float | tc | Truncation of Gaussian, see GlobalGaussianTruncationGet |
| dip_DerivativeFlavour | flavour | Derivative flavour |
The enumerator flavour parameter is one of:
| Name | Description |
| DIP_DF_DEFAULT | Default derivative flavour (==DIP_DF_FIRGAUSS) |
| DIP_DF_FIRGAUSS | Gaussian family, FIR implementation, Gauss |
| DIP_DF_IIRGAUSS | Gaussian family, IIR implementation, GaussIIR |
| DIP_DF_FTGAUSS | Gaussian family, FT implementation, GaussFT |
| DIP_DF_FINITEDIFF | Finite difference implementation, FiniteDifferenceEx |
Lucas J. van Vliet, "Grey-Scale Measurements in Multi-Dimensional Digitized Images", Delft University of Technology, 1993
P.W. Verbeek and L.J. van Vliet, "On the location error of curved edges in low-pass filtered 2-D and 3-D images", IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 16, no. 7, 1994, 726-733.
Derivative, GradientMagnitude, GradientDirection2D, Laplace, Dgg, LaplaceMinDgg