Click or drag to resize
Accord.NET (logo)

Threshold Class

Threshold binarization.
Inheritance Hierarchy
SystemObject
  Accord.Imaging.FiltersBaseInPlacePartialFilter
    Accord.Imaging.FiltersThreshold
      Accord.Imaging.FiltersIterativeThreshold

Namespace:  Accord.Imaging.Filters
Assembly:  Accord.Imaging (in Accord.Imaging.dll) Version: 3.6.0
Syntax
public class Threshold : BaseInPlacePartialFilter
Request Example View Source

The Threshold type exposes the following members.

Constructors
  NameDescription
Public methodThreshold
Initializes a new instance of the Threshold class.
Public methodThreshold(Int32)
Initializes a new instance of the Threshold class.
Top
Properties
Methods
  NameDescription
Public methodApply(Bitmap)
Apply filter to an image.
(Inherited from BaseInPlacePartialFilter.)
Public methodApply(BitmapData)
Apply filter to an image.
(Inherited from BaseInPlacePartialFilter.)
Public methodApply(UnmanagedImage)
Apply filter to an image in unmanaged memory.
(Inherited from BaseInPlacePartialFilter.)
Public methodApply(UnmanagedImage, UnmanagedImage)
Apply filter to an image in unmanaged memory.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(Bitmap)
Apply filter to an image.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(BitmapData)
Apply filter to an image.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(UnmanagedImage)
Apply filter to an unmanaged image.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(Bitmap, Rectangle)
Apply filter to an image or its part.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(BitmapData, Rectangle)
Apply filter to an image or its part.
(Inherited from BaseInPlacePartialFilter.)
Public methodApplyInPlace(UnmanagedImage, Rectangle)
Apply filter to an unmanaged image or its part.
(Inherited from BaseInPlacePartialFilter.)
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 BaseInPlacePartialFilterProcessFilter(UnmanagedImage, Rectangle).)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
Top
Fields
  NameDescription
Protected fieldthreshold
Threshold value.
Top
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 MethodToT
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.)
Top
Remarks

The filter does image binarization using specified threshold value. All pixels with intensities equal or higher than threshold value are converted to white pixels. All other pixels with intensities below threshold value are converted to black pixels.

The filter accepts 8 and 16 bpp grayscale images for processing.

Note Note
Since the filter can be applied as to 8 bpp and to 16 bpp images, the ThresholdValue value should be set appropriately to the pixel format. In the case of 8 bpp images the threshold value is in the [0, 255] range, but in the case of 16 bpp images the threshold value is in the [0, 65535] range.

Sample usage:

// create filter
Threshold filter = new Threshold( 100 );
// apply the filter
filter.ApplyInPlace( image );

Initial image:

Result image:

See Also