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LBitmapBase::GrayScale

#include "ltwrappr.h"

virtual L_INT LBitmapBase::GrayScale(nBitsPerPixel=8)

Converts a 1-, 4-, 8-, 16-, 24-, or 32-bit bitmap to an 8-bit, 12-bit, 16-bit or 32-bit grayscale bitmap. Support for 12 ,16 and 32-bit grayscale images is available only in the Document/Medical toolkits.

Parameters

L_INT nBitsPerPixel

Value indicating the number of bits in the destination bitmap. Valid values are 8, 12, 16, or 32.

Returns

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

Comments

The resulting bitmap can be an 8-bit, 12-bit, 16-bit or 32-bit grayscale bitmap. Once the function is complete, the Order member of the bitmap handle is set to ORDER_GRAY.

When converting to 12-bit, 16-bit or 32-bit grayscale, a Lookup table is not used. When converting to 8-bit grayscale, a Lookup table is used to get the RGB for each input pixel. The grayscale value corresponding to that RGB triple is used in the destination bitmap.

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

Required DLLs and Libraries

LTDIS
LTFIL
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 LBitmapBase__GrayScaleExample() 
{ 
   L_INT nRet; 
   LBitmapBase MyBitmap; 
 
   MyBitmap.SetFileName(MAKE_IMAGE_PATH(TEXT("image1.cmp"))); 
   nRet =MyBitmap.Load(24); 
   if(nRet !=SUCCESS) 
      return nRet; 
   if(MyBitmap.IsGrayScale()==GRAY_NO) 
      nRet = MyBitmap.GrayScale(8); 
 
   return nRet; 
 
}