LBitmap::HighPassFilter

#include "ltwrappr.h"

L_INT LBitmap::HighPassFilter(uRadius, uOpacity, uFlags = 0)

L_UINT uRadius;

/* radius of the neighborhood*/

L_UINT uOpacity;

/* opacity */

L_UINT32 uFlags;

/* flags */

Removes low frequency details in a bitmap, resulting in a sharpened image.

Parameter

Description

uRadius

Value greater than 0 that indicates the radius of the neighborhood on which the filter is applied, in pixels.

uOpacity

Value that represents the intensity of the effect. The valid range is from 0 to 100. At 100, only the object outlines remain.

uFlags

Reserved for future use. Must be 0.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

This filter removes low-frequency detail in the bitmap. The effect is opposite to that of the Gaussian Blur filter (LBitmap::GaussianFilter).

To increase the thickness of the edges, increase the value of uRadius. Usually a low value for uRadius is better.

Unlike the LBitmap::UnsharpMask function, when using this function image noise is not increased.

For an example, click here

If the bitmap has a region, the effect will be applied on the region only.

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.

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

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:

LBitmap::Sharpen, LBitmap::Posterize, LBitmap::Mosaic, LBitmap::Emboss, LBitmap::MedianFilter, LBitmap::AddNoise, LBitmap::IntensityDetect, LBitmap::SpatialFilter, LBitmap::BinaryFilter, LBitmap::Solarize, LBitmap::WindowLevel, LBitmap::WindowLevelExt, LBitmap::UnsharpMask, LBitmap::GaussianFilter

Topics:

Raster Image Functions: Filtering Images

 

Removing Noise

 

Detecting and Enhancing Edges and Lines

 

Raster Image Functions: Functions Where the Region Preempts the Bitmap

 

Raster Image Functions: Modifying Intensity Values

 

Raster Image Functions: Removing Noise

 

Raster Image Functions: Detecting and Enhancing Edges and Lines

Example

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName
L_INT LBitmap__HighPassFilterExample()
{
   L_INT nRet;
   LBitmap LeadBitmap;
   nRet =LeadBitmap.Load(MAKE_IMAGE_PATH(TEXT("IMAGE1.CMP")), 0,ORDER_BGR);
   if(nRet !=SUCCESS)
      return nRet;
   nRet =LeadBitmap.HighPassFilter(10, 100);
   if(nRet !=SUCCESS)
      return nRet;
   return SUCCESS;
}