In This Topic ▼

L_SkeletonBitmap

Summary

Finds the skeleton of objects or regions in a bitmap.

Syntax

#include "l_bitmap.h"

L_LTIMGEFX_API L_INT L_SkeletonBitmap(pBitmap, nThreshold, uFlags)

Parameters

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle that references the bitmap for which to find the skeleton.

L_INT nThreshold

Threshold value used to binarize the bitmap before finding the skeleton. This parameter is ignored if the bitmap is a binary bitmap. The threshold range for 16, 48 and 64-bit images is from 0 to 65535 for unsigned images, and from 32768 to +32767 for signed images. For 12-bit images, the threshold range is from 0 to 4095 for unsigned images, and from 2048 to +2047 for signed images. Otherwise, it is from 0 to 255.

L_UINT32 uFlags

Reserved for future use. Must be 0.

Returns

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

Comments

This function finds the skeleton of regions or objects in a binary bitmap. The white color represents the objects and the black color represents the background. If the bitmap is not a 1-bit image, the threshold will be used to transform the bitmap into a binary image before finding the skeleton.

If the bitmap has a region, this function works only on the region.

This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available in the Document and Medical Imaging toolkits.

To update a status bar or detect a user interrupt during execution of this function, refer to L_SetStatusCallback.

This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.

Skeleton Function - Before

Skeleton Function - After

View additional platform support for this Skeleton function.

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, Linux.

Example

This example loads a bitmap and finds its edges using L_EdgeDetectorBitmap then produces the skeleton of these edges

L_INT SkeletonBitmapExample(L_VOID) 
{ 
   L_INT nRet; 
   BITMAPHANDLE LeadBitmap;   /* Bitmap handle to hold the loaded image. */ 
 
   /* Load the bitmap, keeping the bits per pixel of the file */ 
   nRet = L_LoadBitmap(MAKE_IMAGE_PATH(TEXT("sample5.cmp")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   /* Find the edges in the bitmap*/ 
   nRet = L_EdgeDetectorBitmap(&LeadBitmap, 60, EDG_SOBEL_ALL, 0); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   nRet = L_SkeletonBitmap(&LeadBitmap, 128, 0); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   nRet = L_SaveBitmap(MAKE_IMAGE_PATH(TEXT("Result.BMP")), &LeadBitmap, FILE_BMP, 24, 0, NULL); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   //free bitmap 
   if (LeadBitmap.Flags.Allocated) 
      L_FreeBitmap(&LeadBitmap); 
 
   return SUCCESS; 
}