OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor Class Reference

Class to compute an image descriptor using the bag of visual words. More...

Public Member Functions
	BOWImgDescriptorExtractor (Feature2D dextractor, DescriptorMatcher dmatcher)
	The constructor.
void	compute (Mat image, MatOfKeyPoint keypoints, Mat imgDescriptor)
int	descriptorSize ()
	Returns an image descriptor size if the vocabulary is set. Otherwise, it returns 0.
int	descriptorType ()
	Returns an image descriptor type.
IntPtr	getNativeObjAddr ()
Mat	getVocabulary ()
	Returns the set vocabulary.
void	setVocabulary (Mat vocabulary)
	Sets a visual vocabulary.
Public Member Functions inherited from OpenCVForUnity.DisposableObject
void	Dispose ()
void	ThrowIfDisposed ()

Static Public Member Functions
static BOWImgDescriptorExtractor	__fromPtr__ (IntPtr addr)
Static Public Member Functions inherited from OpenCVForUnity.DisposableObject
static IntPtr	ThrowIfNullIntPtr (IntPtr ptr)

Protected Member Functions
override void	Dispose (bool disposing)
Protected Member Functions inherited from OpenCVForUnity.DisposableOpenCVObject
	DisposableOpenCVObject ()
	DisposableOpenCVObject (bool isEnabledDispose)
	DisposableOpenCVObject (IntPtr ptr)
	DisposableOpenCVObject (IntPtr ptr, bool isEnabledDispose)
override void	Dispose (bool disposing)
Protected Member Functions inherited from OpenCVForUnity.DisposableObject
	DisposableObject ()
	DisposableObject (bool isEnabledDispose)

Additional Inherited Members
Package Attributes inherited from OpenCVForUnity.DisposableOpenCVObject
Properties inherited from OpenCVForUnity.DisposableObject
bool	IsDisposed [get, protected set]
bool	IsEnabledDispose [get, set]

Detailed Description

Class to compute an image descriptor using the bag of visual words.

Such a computation consists of the following steps:

1. Compute descriptors for a given image and its keypoints set.
2. Find the nearest visual words from the vocabulary for each keypoint descriptor.
3. Compute the bag-of-words image descriptor as is a normalized histogram of vocabulary words encountered in the image. The i-th bin of the histogram is a frequency of i-th word of the vocabulary in the given image.

Constructor & Destructor Documentation

BOWImgDescriptorExtractor()

OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.BOWImgDescriptorExtractor	(	Feature2D	dextractor,
		DescriptorMatcher	dmatcher )

The constructor.

Parameters

dextractor	Descriptor extractor that is used to compute descriptors for an input image and its keypoints.
dmatcher	Descriptor matcher that is used to find the nearest word of the trained vocabulary for each keypoint descriptor of the image.

Member Function Documentation

__fromPtr__()

static BOWImgDescriptorExtractor OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.__fromPtr__ ( IntPtr addr )

static

compute()

void OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.compute	(	Mat	image,
		MatOfKeyPoint	keypoints,
		Mat	imgDescriptor )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

keypointDescriptors	Computed descriptors to match with vocabulary.
imgDescriptor	Computed output image descriptor.
pointIdxsOfClusters	Indices of keypoints that belong to the cluster. This means that pointIdxsOfClusters[i] are keypoint indices that belong to the i -th cluster (word of vocabulary) returned if it is non-zero.

descriptorSize()

int OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.descriptorSize

(

)

Returns an image descriptor size if the vocabulary is set. Otherwise, it returns 0.

descriptorType()

int OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.descriptorType

(

)

Returns an image descriptor type.

Dispose()

override void OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.Dispose ( bool disposing )

protectedvirtual

Reimplemented from OpenCVForUnity.DisposableObject.

getNativeObjAddr()

IntPtr OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.getNativeObjAddr

(

)

getVocabulary()

Mat OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.getVocabulary

(

)

Returns the set vocabulary.

setVocabulary()

void OpenCVForUnity.Features2dModule.BOWImgDescriptorExtractor.setVocabulary

(

Mat

vocabulary

)

Sets a visual vocabulary.

Parameters

vocabulary

Vocabulary (can be trained using the inheritor of BOWTrainer ). Each row of the vocabulary is a visual word (cluster center).

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The documentation for this class was generated from the following file:

• OpenCVForUnity/Assets/OpenCVForUnity/org/opencv/features2d/BOWImgDescriptorExtractor.cs