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FrequencyFilter Class
Filtering of frequencies outside of specified range in complex Fourier transformed image.
Inheritance Hierarchy
SystemObject
  Accord.Imaging.ComplexFiltersFrequencyFilter

Namespace:  Accord.Imaging.ComplexFilters
Assembly:  Accord.Imaging (in Accord.Imaging.dll) Version: 3.8.0
Syntax
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public class FrequencyFilter : IComplexFilter
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The FrequencyFilter type exposes the following members.

Constructors
  NameDescription
Public methodFrequencyFilter
Initializes a new instance of the FrequencyFilter class.
Public methodFrequencyFilter(IntRange)
Initializes a new instance of the FrequencyFilter class.
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Properties
  NameDescription
Public propertyFrequencyRange
Range of frequencies to keep.
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Methods
  NameDescription
Public methodApply
Apply filter to complex image.
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.)
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 MethodTo(Type)Overloaded.
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 ExtensionMethods.)
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Remarks

The filer keeps only specified range of frequencies in complex Fourier transformed image. The rest of frequencies are zeroed.

Sample usage:

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// create complex image
ComplexImage complexImage = ComplexImage.FromBitmap( image );
// do forward Fourier transformation
complexImage.ForwardFourierTransform( );
// create filter
FrequencyFilter filter = new FrequencyFilter( new IntRange( 20, 128 ) );
// apply filter
filter.Apply( complexImage );
// do backward Fourier transformation
complexImage.BackwardFourierTransform( );
// get complex image as bitmat
Bitmap fourierImage = complexImage.ToBitmap( );

Initial image:

Fourier image:

See Also