Morphological high-pass filter
#include "dip_morphology.h"
dip_Error dip_Tophat ( in, out, se, boundary, filterParam, shape, edgeType, polarity )
integer, float
The top-hat is the difference between a morphological operation and the original image, comparable to a high-pass filter. Which operation is used can be chosen through the dip_MphEdgeType and dip_MphTophatPolarity parameters.
The rectangular, elliptic and diamond structuring elements are "flat", i.e. these structuring elements have a constant value. For these structuring elements, filterParam determines the sizes of the structuring elements. When shape is set to DIP_FLT_SHAPE_PARABOLIC, filterParams specifies the curvature of the parabola. When shape is set to DIP_FLT_SHAPE_STRUCTURING_ELEMENT, se is used as structuring element. It can be either a binary or a grey-value image, but be careful: it is converted to the same data type as the input image, and might therefore be clipped or loose precision. It is required (in the current implementation) that the structuring element be odd in size. Its origin is the center.
If shape is not equal to DIP_FLT_SHAPE_STRUCTURING_ELEMENT, se is allowed to be set to zero. When shape is set to DIP_FLT_SHAPE_STRUCTURING_ELEMENT, filterParam is ignored, (and can be set to zero).
| Data type | Name | Description |
| dip_Image | in | Input |
| dip_Image | out | Output |
| dip_Image | se | Structuring element |
| dip_BoundaryArray | boundary | Boundary conditions |
| dip_FloatArray | filterParam | Filter parameters |
| dip_FilterShape | shape | Filter shape |
| dip_MphEdgeType | edgeType | edgeType |
| dip_MphTophatPolarity | polarity | polarity |
The enumerator dip_FilterShape contains the following constants:
| Name | Description |
| DIP_FLT_SHAPE_DEFAULT | default structuring element, same as DIP_FLT_SHAPE_RECTANGULAR |
| DIP_FLT_SHAPE_RECTANGULAR | rectangular structuring element |
| DIP_FLT_SHAPE_ELLIPTIC | elliptic structuring element |
| DIP_FLT_SHAPE_DIAMOND | diamond shaped structuring element |
| DIP_FLT_SHAPE_PARABOLIC | parabolic structuring element |
| DIP_FLT_SHAPE_STRUCTURING_ELEMENT | use se as structuring element |
The enumerator dip_MphEdgeType contains the following constants:
| Name | Description |
| DIP_MPH_TEXTURE | Response is limited to edges in texture |
| DIP_MPH_OBJECT | Response is limited to object edges |
| DIP_MPH_BOTH | All edges produce equal response |
The enumerator dip_MphTophatPolarity contains the following constants:
| Name | Description |
| DIP_MPH_TEXTURE | Response is limited to edges in texture |
| DIP_MPH_OBJECT | Response is limited to object edges |
| DIP_MPH_BOTH | All edges produce equal response |
Lee, MorphologicalGradientMagnitude, MorphologicalRange, MultiScaleMorphologicalGradient, MorphologicalSmoothing, MorphologicalThreshold
DIPlib on-line documentation | Function reference | Global function index