ImageDev

UnsharpMasking2d

Sharpens edges on the elements of a two-dimensional image without increasing noise.

Access to parameter description

For an introduction to image filters: see section Images Filtering.

This algorithm is a very common filter that sharpens edges on the elements of an image without increasing noise. It first applies a Gaussian filter to a copy of the original image and blends it with the original. Undesired effects are finally reduced by using a mask to apply the sharpening only on the desired regions (that is, regions for which the gradient is above a certain threshold).

<b> Figure 1.</b> The unsharp masking filter effect
Figure 1. The unsharp masking filter effect

Note: Since the original data range is not preserved by this filter, the output image type is upgraded according to the Image type basic rule.

See also

Function Syntax

This function returns the outputImage output parameter. 
// Function prototype.
std::shared_ptr< iolink::ImageView >
unsharpMasking2d( std::shared_ptr< iolink::ImageView > inputImage,
                  double edgeSize,
                  double edgeContrast,
                  double brightnessThreshold,
                  std::shared_ptr< iolink::ImageView > outputImage = NULL );
This function returns the outputImage output parameter. 
// Function prototype.
unsharp_masking_2d( input_image,
                    edge_size = 5,
                    edge_contrast = 0.5,
                    brightness_threshold = 0,
                    output_image = None )
This function returns the outputImage output parameter. 
// Function prototype.
public static IOLink.ImageView
UnsharpMasking2d( IOLink.ImageView inputImage,
                  double edgeSize = 5,
                  double edgeContrast = 0.5,
                  double brightnessThreshold = 0,
                  IOLink.ImageView outputImage = null );

Class Syntax

Parameters

Class Name UnsharpMasking2d

Parameter Name Description Type Supported Values Default Value
input
inputImage
The input image. Image Binary, Label, Grayscale or Multispectral nullptr
input
edgeSize
The radius of the desired edges. Float64 >0 5
input
edgeContrast
The contrast amount added at the edges. Float64 >0 0.5
input
brightnessThreshold
The minimum brightness threshold. Float64 >=0 0
output
outputImage
The output image. Its dimensions are forced to the same values as the input. Its data type is promoted. Image nullptr

Object Examples

std::shared_ptr< iolink::ImageView > polystyrene = ioformat::readImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "polystyrene.tif" );

UnsharpMasking2d unsharpMasking2dAlgo;
unsharpMasking2dAlgo.setInputImage( polystyrene );
unsharpMasking2dAlgo.setEdgeSize( 5.0 );
unsharpMasking2dAlgo.setEdgeContrast( 0.5 );
unsharpMasking2dAlgo.setBrightnessThreshold( 0.0 );
unsharpMasking2dAlgo.execute();

std::cout << "outputImage:" << unsharpMasking2dAlgo.outputImage()->toString();

polystyrene = ioformat.read_image(imagedev_data.get_image_path("polystyrene.tif"))

unsharp_masking_2d_algo = imagedev.UnsharpMasking2d()
unsharp_masking_2d_algo.input_image = polystyrene
unsharp_masking_2d_algo.edge_size = 5.0
unsharp_masking_2d_algo.edge_contrast = 0.5
unsharp_masking_2d_algo.brightness_threshold = 0.0
unsharp_masking_2d_algo.execute()

print( "output_image:", str( unsharp_masking_2d_algo.output_image ) )

ImageView polystyrene = ViewIO.ReadImage( @"Data/images/polystyrene.tif" );

UnsharpMasking2d unsharpMasking2dAlgo = new UnsharpMasking2d
{
    inputImage = polystyrene,
    edgeSize = 5.0,
    edgeContrast = 0.5,
    brightnessThreshold = 0.0
};
unsharpMasking2dAlgo.Execute();

Console.WriteLine( "outputImage:" + unsharpMasking2dAlgo.outputImage.ToString() );

Function Examples

std::shared_ptr< iolink::ImageView > polystyrene = ioformat::readImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "polystyrene.tif" );

auto result = unsharpMasking2d( polystyrene, 5.0, 0.5, 0.0 );

std::cout << "outputImage:" << result->toString();

polystyrene = ioformat.read_image(imagedev_data.get_image_path("polystyrene.tif"))

result = imagedev.unsharp_masking_2d( polystyrene, 5.0, 0.5, 0.0 )

print( "output_image:", str( result ) )

ImageView polystyrene = ViewIO.ReadImage( @"Data/images/polystyrene.tif" );

IOLink.ImageView result = Processing.UnsharpMasking2d( polystyrene, 5.0, 0.5, 0.0 );

Console.WriteLine( "outputImage:" + result.ToString() );