L_GaussianFilterBitmap

#include "l_bitmap.h"

L_LTIMGEFX_API L_INT L_GaussianFilterBitmap(pBitmap, nRadius, uFlags)

pBITMAPHANDLE pBitmap;

/* pointer to a bitmap handle */

L_INT nRadius;

/* radius of the neighborhood */

L_UINT32 uFlags;

/* flags */

Smooths or blurs an image by applying a Gaussian filter to the specified bitmap.

Parameter

Description

pBitmap

Pointer to a bitmap handle that references the bitmap to process with the Gaussian filter.

nRadius

Value that indicates the radius of the neighborhood on which the filter is applied.

uFlags

Reserved for future use. Must be 0.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

Each pixel in the bitmap is blurred based on neighborhood pixels. The parameter nRadius determines the size of the neighborhood to consider when blurring a pixel. The result is a blurred version of the original image.

The amount of blur is controlled by specifying the size of the neighborhood used for blurring or smoothing. The value of the nRadius parameter determines the size and values of the mask.

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

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.

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

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.

See Also

Functions:

L_SharpenBitmap, L_PosterizeBitmap, L_MosaicBitmap, L_EmbossBitmap, L_MedianFilterBitmap, L_AddBitmapNoise, L_IntensityDetectBitmap, L_SpatialFilterBitmap, L_BinaryFilterBitmap, L_SolarizeBitmap, L_DlgGaussianBlur, L_WindowLevel, L_UnsharpMaskBitmap, L_HighPassFilterBitmap, L_BricksTextureBitmap, L_DeskewBitmap, L_DiffuseGlowBitmap, L_GlowFilterBitmap, L_HalfTonePatternBitmap, L_HighPassFilterBitmap, L_MaskConvolutionBitmap, L_PerspectiveBitmap, L_PlasmaFilterBitmap, L_PointillistBitmap, L_FragmentBitmap, L_HighPassFilterBitmap, L_UnsharpMaskBitmap

Topics:

Raster Image Functions: Filtering Images

 

Removing Noise

 

Raster Image Functions: Detecting and Enhancing Edges and Lines

Example

This example loads a bitmap and applies the Gaussian filter 

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName


#if defined (LEADTOOLS_V16_OR_LATER)
 L_INT GaussianFilterBitmapExample(L_VOID)
{
   L_INT nRet;
   BITMAPHANDLE LeadBitmap;   
   nRet = L_LoadBitmap (MAKE_IMAGE_PATH(TEXT("IMAGE1.CMP")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
   if(nRet !=SUCCESS)
      return nRet;
   nRet = L_GaussianFilterBitmap (&LeadBitmap, 20, 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;
}
#else
 L_INT GaussianFilterBitmapExample(L_VOID)
{
   L_INT nRet;
   BITMAPHANDLE LeadBitmap;   
   nRet = L_LoadBitmap (MAKE_IMAGE_PATH(TEXT("IMAGE1.CMP")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
   if(nRet !=SUCCESS)
      return nRet;
   nRet = L_GaussianFilterBitmap (&LeadBitmap, 20);
   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;
}
#endif // LEADTOOLS_V16_OR_LATER