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LBitmap::GetFeretsDiameter

Summary

Computes the Ferets diameter of an object (the maximum distance between the points of the perimeter of the region), and finds its end points.

Syntax

#include "ltwrappr.h"

static L_INT LBitmap::GetFeretsDiameter (pPoints, uSize, puFeretsDiameter, puFirstIndex, puSecondIndex, uFlags = 0)

Parameters

POINT * pPoints

Pointer to an array of object contour coordinate points.

L_UINT * puFeretsDiameter

Pointer to a variable to be updated with the length of the Ferets diameter. The length is measured in pixels and is internally multiplied by 1000. Divide this value by 1000 to obtain the real length.

L_UINT * puFirstIndex

Pointer to a variable to be updated with index of the first end point of the Ferets diameter.

L_UINT * puSecondIndex

Pointer to a variable to be updated with index of the second end point of the Ferets diameter.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function calculates the Feret's Diameter (caliper length), the longest distance between any two points along the boundary. This is equivalent to the minimum diameter of a tube through which this object can pass.

This function does not call the status callback.

Required DLLs and Libraries

LTIMGEFX
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

Example

L_INT LBitmap__GetFeretsDiameterExample(LBitmap *pLeadBitmap)  
{ 
   L_INT nRet; 
   RECT rcRect;  
   POINT  * pPoints;  
   L_UINT  uSize, uFeretsDiam, uFstIndex, uSndIndex;  
   RGNXFORM MyXForm;  
 
   rcRect.top = pLeadBitmap->GetHeight ()/4;  
   rcRect.bottom = pLeadBitmap->GetHeight ()*3/4;  
   rcRect.left = pLeadBitmap->GetWidth ()/4;  
   rcRect.right = pLeadBitmap->GetWidth ()*3/4;  
    
   nRet =pLeadBitmap->Region()->SetRgnEllipse (&rcRect); 
   if(nRet !=SUCCESS) 
      return nRet; 
   nRet =pLeadBitmap->Region()->GetRgnXForm (&MyXForm); 
   if(nRet !=SUCCESS) 
      return nRet; 
   nRet =pLeadBitmap->GetRgnContourPoints(&MyXForm,&pPoints, &uSize,0); 
   if(nRet !=SUCCESS) 
      return nRet; 
   nRet =LBitmap::GetFeretsDiameter (pPoints, uSize, &uFeretsDiam, &uFstIndex, &uSndIndex); 
   if(nRet !=SUCCESS) 
      return nRet; 
 
   return SUCCESS; 
}