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LBitmap::SpatialFilter

Summary

Imposes a spatial filter on the class object's bitmap. You can supply your own filter or use one of the predefined filters.

Syntax

#include "ltwrappr.h"

virtual L_INT LBitmap::SpatialFilter(pFilter, uFlags = 0)

Parameters

pSPATIALFLT pFilter

Pointer to the spatial filter to use. For predefined filters, refer to List of Spatial Filters. To define your own filter, refer to SPATIALFLT.

Returns

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

Comments

Imposes a spatial filter on the class object's bitmap. You can supply your own filter or use one of the predefined filters. A spatial filter recomputes the brightness of each pixel in a bitmap by using a weighted averaging technique that considers the surrounding pixels. Spatial filters are used for operations such as sharpening an image or detecting edges within the image.

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 only in the Document/Medical toolkits.

The [LBitmap:SpatialFilter function works best with 24-bit, 16-bit, or grayscale bitmaps. If a bitmap uses a color palette, this function matches the new brightness value of each pixel to the nearest color in the existing palette.

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

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.

Required DLLs and Libraries

LTDIS
LTFIL
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__SpatialFilterExample() 
{ 
   L_INT nRet; 
   LBitmap LeadBitmap; 
 
   nRet =LeadBitmap.Load(MAKE_IMAGE_PATH(TEXT("ImageProcessingDemo\\NaturalFruits.jpg")), 0,ORDER_BGR); 
   if(nRet !=SUCCESS) 
      return nRet; 
 
   return LeadBitmap.SpatialFilter(FLT_PREWITT_HORZ); 
}