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DifferenceOfGaussians Class

Difference of Gaussians filter.
Inheritance Hierarchy
SystemObject
  Accord.Imaging.FiltersBaseInPlaceFilter
    Accord.Imaging.FiltersDifferenceOfGaussians

Namespace:  Accord.Imaging.Filters
Assembly:  Accord.Imaging (in Accord.Imaging.dll) Version: 3.5.0
Syntax
public class DifferenceOfGaussians : BaseInPlaceFilter
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The DifferenceOfGaussians type exposes the following members.

Constructors
  NameDescription
Public methodDifferenceOfGaussians
Initializes a new instance of the DifferenceOfGaussians class.
Public methodDifferenceOfGaussians(Int32, Int32)
Initializes a new instance of the DifferenceOfGaussians class.
Public methodDifferenceOfGaussians(Int32, Int32, Double)
Initializes a new instance of the DifferenceOfGaussians class.
Public methodDifferenceOfGaussians(Int32, Int32, Double, Double)
Initializes a new instance of the DifferenceOfGaussians class.
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Properties
  NameDescription
Public propertyFirst
Gets or sets the first Gaussian filter.
Public propertyFormatTranslations
Format translations dictionary.
(Overrides BaseInPlaceFilterFormatTranslations.)
Public propertySecond
Gets or sets the second Gaussian filter.
Public propertySubtract
Gets or sets the subtract filter used to compute the difference of the two Gaussian blurs.
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Methods
  NameDescription
Public methodApply(Bitmap)
Apply filter to an image.
(Inherited from BaseInPlaceFilter.)
Public methodApply(BitmapData)
Apply filter to an image.
(Inherited from BaseInPlaceFilter.)
Public methodApply(UnmanagedImage)
Apply filter to an image in unmanaged memory.
(Inherited from BaseInPlaceFilter.)
Public methodApply(UnmanagedImage, UnmanagedImage)
Apply filter to an image in unmanaged memory.
(Inherited from BaseInPlaceFilter.)
Public methodApplyInPlace(Bitmap)
Apply filter to an image.
(Inherited from BaseInPlaceFilter.)
Public methodApplyInPlace(BitmapData)
Apply filter to an image.
(Inherited from BaseInPlaceFilter.)
Public methodApplyInPlace(UnmanagedImage)
Apply filter to an unmanaged image.
(Inherited from BaseInPlaceFilter.)
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Protected methodProcessFilter
Process the filter on the specified image.
(Overrides BaseInPlaceFilterProcessFilter(UnmanagedImage).)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
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Extension Methods
  NameDescription
Public Extension MethodHasMethod
Checks whether an object implements a method with the given name.
(Defined by ExtensionMethods.)
Public Extension MethodIsEqual
Compares two objects for equality, performing an elementwise comparison if the elements are vectors or matrices.
(Defined by Matrix.)
Public Extension MethodToTOverloaded.
Converts an object into another type, irrespective of whether the conversion can be done at compile time or not. This can be used to convert generic types to numeric types during runtime.
(Defined by ExtensionMethods.)
Public Extension MethodToTOverloaded.
Converts an object into another type, irrespective of whether the conversion can be done at compile time or not. This can be used to convert generic types to numeric types during runtime.
(Defined by Matrix.)
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Remarks

In imaging science, the difference of Gaussians is a feature enhancement algorithm that involves the subtraction of one blurred version of an original image from another, less blurred version of the original.

In the simple case of grayscale images, the blurred images are obtained by convolving the original grayscale images with Gaussian kernels having differing standard deviations. Blurring an image using a Gaussian kernel suppresses only high-frequency spatial information. Subtracting one image from the other preserves spatial information that lies between the range of frequencies that are preserved in the two blurred images. Thus, the difference of Gaussians is a band-pass filter that discards all but a handful of spatial frequencies that are present in the original grayscale image.

This filter implementation has been contributed by Diego Catalano.

References:

  • Wikipedia contributors. "Difference of Gaussians." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 1 Jun. 2013. Web. 10 Feb. 2014.

Examples
Bitmap image = ... // Lena's famous picture

// Create a new Difference of Gaussians
var DoG = new DifferenceOfGaussians();

// Apply the filter
Bitmap result = DoG.Apply(image);

// Show on the screen
ImageBox.Show(result);

The resulting image is shown below.

See Also