.#include "BIVISION.H"
HANDLE CALLBACK FilterEdgeGR( HANDLE hSrcDIB,
int iMaxDiff,
NormOperator lpNormOp,
BOOL bShowDialog)
Description
This function will find edges on the input image by the Gary Regent edge detection method. This function works for 8 and 24 bit per pixel images. Gary Regent edge-detection is a region growing based edge detection method. Detected edges are usually topologically circles (closed arcs without intersections). Region growing can be tuned with iMaxDiff parameter. The smaller the iMaxDiff parameter is, the more regions rise. In case of color images, the Red, Green and Blue values of a pixel should be transformed to only one value. The lpNormOp parameter is a handler of a transformator function implemented by the user, or NULL. In this case a default transformator function is used (square mean values). If the input image has too sawtooth local distributions, a high number of regions can be rised, and too much edges will be found. In this case, choose a larger iMaxDiff value. If iMaxDiff is negative, Bryant difference will be used (square means normalized to .
Examples
Parameters
|
HANDLE |
hSrcDIB |
Source DIB |
|
int |
iMaxDiff |
Maximum different during region growing. See Description for further information. |
|
NormOperator |
lpNormOpFunc |
If the input DIB is a color image, one pixel’s Red, Green and Blue values must be transformed to only one value. This parameter is a pointer to a function retrieving the 3 BYTE type color value and returning one BYTE value. See the formal definition of this function below at programming notes. If this pointer is NULL, the default transformation function will be used (square mean of the 3 values). |
|
BOOL |
bShowDialog |
This parameter specifies the displaying of the parameter dialog. IMPORTANT: The parameter dialog will only display, if there is BiDlgs.dll installed. |
Return values
Handle of the newly created DIB on success or NULL on failure.
Programming notes
typedef BYTE (CALLBACK *NormOperator)(BYTE nRedValue, BYTE nGreenValue, BYTE nBlueValue);
Requirements
Header : Declared in BiVision.h; include BiVision.h.
Library : Use BiVision.lib.
DLLs : BiVision.dll.