OpenCV  3.2.0-dev
Open Source Computer Vision

Class implementing the ORB (oriented BRIEF) keypoint detector and descriptor extractor. More...

#include "cudafeatures2d.hpp"

Inheritance diagram for cv::cuda::ORB:
Collaboration diagram for cv::cuda::ORB:

Public Types

enum  {
  kBytes = 32,
  HARRIS_SCORE =0,
  FAST_SCORE =1
}
 
enum  {
  X_ROW = 0,
  Y_ROW,
  RESPONSE_ROW,
  ANGLE_ROW,
  OCTAVE_ROW,
  SIZE_ROW,
  ROWS_COUNT
}
 

Public Member Functions

virtual void clear ()
 Clears the algorithm state. More...
 
virtual void compute (InputArray image, std::vector< KeyPoint > &keypoints, OutputArray descriptors)
 Computes the descriptors for a set of keypoints detected in an image (first variant) or image set (second variant). More...
 
virtual void compute (InputArrayOfArrays images, std::vector< std::vector< KeyPoint > > &keypoints, OutputArrayOfArrays descriptors)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. More...
 
virtual void computeAsync (InputArray image, OutputArray keypoints, OutputArray descriptors, Stream &stream=Stream::Null())
 Computes the descriptors for a set of keypoints detected in an image. More...
 
virtual void convert (InputArray gpu_keypoints, std::vector< KeyPoint > &keypoints)=0
 Converts keypoints array from internal representation to standard vector. More...
 
virtual int defaultNorm () const
 
virtual int descriptorSize () const
 
virtual int descriptorType () const
 
virtual void detect (InputArray image, std::vector< KeyPoint > &keypoints, InputArray mask=noArray())
 Detects keypoints in an image (first variant) or image set (second variant). More...
 
virtual void detect (InputArrayOfArrays images, std::vector< std::vector< KeyPoint > > &keypoints, InputArrayOfArrays masks=noArray())
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. More...
 
virtual void detectAndCompute (InputArray image, InputArray mask, std::vector< KeyPoint > &keypoints, OutputArray descriptors, bool useProvidedKeypoints=false)
 Detects keypoints and computes the descriptors. More...
 
virtual void detectAndComputeAsync (InputArray image, InputArray mask, OutputArray keypoints, OutputArray descriptors, bool useProvidedKeypoints=false, Stream &stream=Stream::Null())
 Detects keypoints and computes the descriptors. More...
 
virtual void detectAsync (InputArray image, OutputArray keypoints, InputArray mask=noArray(), Stream &stream=Stream::Null())
 Detects keypoints in an image. More...
 
virtual bool empty () const
 Return true if detector object is empty. More...
 
virtual bool getBlurForDescriptor () const =0
 
virtual String getDefaultName () const
 Returns the algorithm string identifier. More...
 
virtual int getEdgeThreshold () const =0
 
virtual int getFastThreshold () const =0
 
virtual int getFirstLevel () const =0
 
virtual int getMaxFeatures () const =0
 
virtual int getNLevels () const =0
 
virtual int getPatchSize () const =0
 
virtual double getScaleFactor () const =0
 
virtual int getScoreType () const =0
 
virtual int getWTA_K () const =0
 
void read (const String &fileName)
 
virtual void read (const FileNode &)
 Reads algorithm parameters from a file storage. More...
 
virtual void save (const String &filename) const
 Saves the algorithm to a file. More...
 
virtual void setBlurForDescriptor (bool blurForDescriptor)=0
 if true, image will be blurred before descriptors calculation More...
 
virtual void setEdgeThreshold (int edgeThreshold)=0
 
virtual void setFastThreshold (int fastThreshold)=0
 
virtual void setFirstLevel (int firstLevel)=0
 
virtual void setMaxFeatures (int maxFeatures)=0
 
virtual void setNLevels (int nlevels)=0
 
virtual void setPatchSize (int patchSize)=0
 
virtual void setScaleFactor (double scaleFactor)=0
 
virtual void setScoreType (int scoreType)=0
 
virtual void setWTA_K (int wta_k)=0
 
void write (const String &fileName) const
 
virtual void write (FileStorage &) const
 Stores algorithm parameters in a file storage. More...
 

Static Public Member Functions

static Ptr< ORBcreate (int nfeatures=500, float scaleFactor=1.2f, int nlevels=8, int edgeThreshold=31, int firstLevel=0, int WTA_K=2, int scoreType=ORB::HARRIS_SCORE, int patchSize=31, int fastThreshold=20)
 The ORB constructor. More...
 
static Ptr< ORBcreate (int nfeatures=500, float scaleFactor=1.2f, int nlevels=8, int edgeThreshold=31, int firstLevel=0, int WTA_K=2, int scoreType=ORB::HARRIS_SCORE, int patchSize=31, int fastThreshold=20, bool blurForDescriptor=false)
 
template<typename _Tp >
static Ptr< _Tp > load (const String &filename, const String &objname=String())
 Loads algorithm from the file. More...
 
template<typename _Tp >
static Ptr< _Tp > loadFromString (const String &strModel, const String &objname=String())
 Loads algorithm from a String. More...
 

Protected Member Functions

void writeFormat (FileStorage &fs) const
 

Detailed Description

Class implementing the ORB (oriented BRIEF) keypoint detector and descriptor extractor.

See also
cv::ORB

Member Enumeration Documentation

anonymous enum
inherited
Enumerator
kBytes 
HARRIS_SCORE 
FAST_SCORE 
anonymous enum
Enumerator
X_ROW 
Y_ROW 
RESPONSE_ROW 
ANGLE_ROW 
OCTAVE_ROW 
SIZE_ROW 
ROWS_COUNT 

Member Function Documentation

virtual void cv::Algorithm::clear ( )
inlinevirtualinherited

Clears the algorithm state.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::cuda::DescriptorMatcher.

virtual void cv::Feature2D::compute ( InputArray  image,
std::vector< KeyPoint > &  keypoints,
OutputArray  descriptors 
)
virtualinherited

Computes the descriptors for a set of keypoints detected in an image (first variant) or image set (second variant).

Parameters
imageImage.
keypointsInput collection of keypoints. Keypoints for which a descriptor cannot be computed are removed. Sometimes new keypoints can be added, for example: SIFT duplicates keypoint with several dominant orientations (for each orientation).
descriptorsComputed descriptors. In the second variant of the method descriptors[i] are descriptors computed for a keypoints[i]. Row j is the keypoints (or keypoints[i]) is the descriptor for keypoint j-th keypoint.
virtual void cv::Feature2D::compute ( InputArrayOfArrays  images,
std::vector< std::vector< KeyPoint > > &  keypoints,
OutputArrayOfArrays  descriptors 
)
virtualinherited

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

Parameters
imagesImage set.
keypointsInput collection of keypoints. Keypoints for which a descriptor cannot be computed are removed. Sometimes new keypoints can be added, for example: SIFT duplicates keypoint with several dominant orientations (for each orientation).
descriptorsComputed descriptors. In the second variant of the method descriptors[i] are descriptors computed for a keypoints[i]. Row j is the keypoints (or keypoints[i]) is the descriptor for keypoint j-th keypoint.
virtual void cv::cuda::Feature2DAsync::computeAsync ( InputArray  image,
OutputArray  keypoints,
OutputArray  descriptors,
Stream stream = Stream::Null() 
)
virtualinherited

Computes the descriptors for a set of keypoints detected in an image.

Parameters
imageImage.
keypointsInput collection of keypoints.
descriptorsComputed descriptors. Row j is the descriptor for j-th keypoint.
streamCUDA stream.
virtual void cv::cuda::Feature2DAsync::convert ( InputArray  gpu_keypoints,
std::vector< KeyPoint > &  keypoints 
)
pure virtualinherited

Converts keypoints array from internal representation to standard vector.

static Ptr<ORB> cv::ORB::create ( int  nfeatures = 500,
float  scaleFactor = 1.2f,
int  nlevels = 8,
int  edgeThreshold = 31,
int  firstLevel = 0,
int  WTA_K = 2,
int  scoreType = ORB::HARRIS_SCORE,
int  patchSize = 31,
int  fastThreshold = 20 
)
staticinherited

The ORB constructor.

Parameters
nfeaturesThe maximum number of features to retain.
scaleFactorPyramid decimation ratio, greater than 1. scaleFactor==2 means the classical pyramid, where each next level has 4x less pixels than the previous, but such a big scale factor will degrade feature matching scores dramatically. On the other hand, too close to 1 scale factor will mean that to cover certain scale range you will need more pyramid levels and so the speed will suffer.
nlevelsThe number of pyramid levels. The smallest level will have linear size equal to input_image_linear_size/pow(scaleFactor, nlevels).
edgeThresholdThis is size of the border where the features are not detected. It should roughly match the patchSize parameter.
firstLevelIt should be 0 in the current implementation.
WTA_KThe number of points that produce each element of the oriented BRIEF descriptor. The default value 2 means the BRIEF where we take a random point pair and compare their brightnesses, so we get 0/1 response. Other possible values are 3 and 4. For example, 3 means that we take 3 random points (of course, those point coordinates are random, but they are generated from the pre-defined seed, so each element of BRIEF descriptor is computed deterministically from the pixel rectangle), find point of maximum brightness and output index of the winner (0, 1 or 2). Such output will occupy 2 bits, and therefore it will need a special variant of Hamming distance, denoted as NORM_HAMMING2 (2 bits per bin). When WTA_K=4, we take 4 random points to compute each bin (that will also occupy 2 bits with possible values 0, 1, 2 or 3).
scoreTypeThe default HARRIS_SCORE means that Harris algorithm is used to rank features (the score is written to KeyPoint::score and is used to retain best nfeatures features); FAST_SCORE is alternative value of the parameter that produces slightly less stable keypoints, but it is a little faster to compute.
patchSizesize of the patch used by the oriented BRIEF descriptor. Of course, on smaller pyramid layers the perceived image area covered by a feature will be larger.
fastThreshold
static Ptr<ORB> cv::cuda::ORB::create ( int  nfeatures = 500,
float  scaleFactor = 1.2f,
int  nlevels = 8,
int  edgeThreshold = 31,
int  firstLevel = 0,
int  WTA_K = 2,
int  scoreType = ORB::HARRIS_SCORE,
int  patchSize = 31,
int  fastThreshold = 20,
bool  blurForDescriptor = false 
)
static
virtual int cv::Feature2D::defaultNorm ( ) const
virtualinherited
virtual int cv::Feature2D::descriptorSize ( ) const
virtualinherited
virtual int cv::Feature2D::descriptorType ( ) const
virtualinherited
virtual void cv::Feature2D::detect ( InputArray  image,
std::vector< KeyPoint > &  keypoints,
InputArray  mask = noArray() 
)
virtualinherited

Detects keypoints in an image (first variant) or image set (second variant).

Parameters
imageImage.
keypointsThe detected keypoints. In the second variant of the method keypoints[i] is a set of keypoints detected in images[i] .
maskMask specifying where to look for keypoints (optional). It must be a 8-bit integer matrix with non-zero values in the region of interest.

Reimplemented in cv::AgastFeatureDetector_Impl.

virtual void cv::Feature2D::detect ( InputArrayOfArrays  images,
std::vector< std::vector< KeyPoint > > &  keypoints,
InputArrayOfArrays  masks = noArray() 
)
virtualinherited

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

Parameters
imagesImage set.
keypointsThe detected keypoints. In the second variant of the method keypoints[i] is a set of keypoints detected in images[i] .
masksMasks for each input image specifying where to look for keypoints (optional). masks[i] is a mask for images[i].
virtual void cv::Feature2D::detectAndCompute ( InputArray  image,
InputArray  mask,
std::vector< KeyPoint > &  keypoints,
OutputArray  descriptors,
bool  useProvidedKeypoints = false 
)
virtualinherited

Detects keypoints and computes the descriptors.

virtual void cv::cuda::Feature2DAsync::detectAndComputeAsync ( InputArray  image,
InputArray  mask,
OutputArray  keypoints,
OutputArray  descriptors,
bool  useProvidedKeypoints = false,
Stream stream = Stream::Null() 
)
virtualinherited

Detects keypoints and computes the descriptors.

virtual void cv::cuda::Feature2DAsync::detectAsync ( InputArray  image,
OutputArray  keypoints,
InputArray  mask = noArray(),
Stream stream = Stream::Null() 
)
virtualinherited

Detects keypoints in an image.

Parameters
imageImage.
keypointsThe detected keypoints.
maskMask specifying where to look for keypoints (optional). It must be a 8-bit integer matrix with non-zero values in the region of interest.
streamCUDA stream.
virtual bool cv::Feature2D::empty ( ) const
virtualinherited

Return true if detector object is empty.

Reimplemented from cv::Algorithm.

virtual bool cv::cuda::ORB::getBlurForDescriptor ( ) const
pure virtual
virtual String cv::Algorithm::getDefaultName ( ) const
virtualinherited

Returns the algorithm string identifier.

This string is used as top level xml/yml node tag when the object is saved to a file or string.

virtual int cv::ORB::getEdgeThreshold ( ) const
pure virtualinherited
virtual int cv::ORB::getFastThreshold ( ) const
pure virtualinherited
virtual int cv::ORB::getFirstLevel ( ) const
pure virtualinherited
virtual int cv::ORB::getMaxFeatures ( ) const
pure virtualinherited
virtual int cv::ORB::getNLevels ( ) const
pure virtualinherited
virtual int cv::ORB::getPatchSize ( ) const
pure virtualinherited
virtual double cv::ORB::getScaleFactor ( ) const
pure virtualinherited
virtual int cv::ORB::getScoreType ( ) const
pure virtualinherited
virtual int cv::ORB::getWTA_K ( ) const
pure virtualinherited
template<typename _Tp >
static Ptr<_Tp> cv::Algorithm::load ( const String filename,
const String objname = String() 
)
inlinestaticinherited

Loads algorithm from the file.

Parameters
filenameName of the file to read.
objnameThe optional name of the node to read (if empty, the first top-level node will be used)

This is static template method of Algorithm. It's usage is following (in the case of SVM):

Ptr<SVM> svm = Algorithm::load<SVM>("my_svm_model.xml");

In order to make this method work, the derived class must overwrite Algorithm::read(const FileNode& fn).

References cv::Ptr< T >::empty(), cv::FileNode::empty(), cv::FileStorage::getFirstTopLevelNode(), and cv::FileStorage::READ.

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template<typename _Tp >
static Ptr<_Tp> cv::Algorithm::loadFromString ( const String strModel,
const String objname = String() 
)
inlinestaticinherited

Loads algorithm from a String.

Parameters
strModelThe string variable containing the model you want to load.
objnameThe optional name of the node to read (if empty, the first top-level node will be used)

This is static template method of Algorithm. It's usage is following (in the case of SVM):

Ptr<SVM> svm = Algorithm::loadFromString<SVM>(myStringModel);

References CV_WRAP, cv::Ptr< T >::empty(), cv::FileNode::empty(), cv::FileStorage::getFirstTopLevelNode(), cv::FileStorage::MEMORY, and cv::FileStorage::READ.

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void cv::Feature2D::read ( const String fileName)
inherited
virtual void cv::Feature2D::read ( const FileNode fn)
virtualinherited

Reads algorithm parameters from a file storage.

Reimplemented from cv::Algorithm.

virtual void cv::Algorithm::save ( const String filename) const
virtualinherited

Saves the algorithm to a file.

In order to make this method work, the derived class must implement Algorithm::write(FileStorage& fs).

virtual void cv::cuda::ORB::setBlurForDescriptor ( bool  blurForDescriptor)
pure virtual

if true, image will be blurred before descriptors calculation

virtual void cv::ORB::setEdgeThreshold ( int  edgeThreshold)
pure virtualinherited
virtual void cv::ORB::setFastThreshold ( int  fastThreshold)
pure virtualinherited
virtual void cv::ORB::setFirstLevel ( int  firstLevel)
pure virtualinherited
virtual void cv::ORB::setMaxFeatures ( int  maxFeatures)
pure virtualinherited
virtual void cv::ORB::setNLevels ( int  nlevels)
pure virtualinherited
virtual void cv::ORB::setPatchSize ( int  patchSize)
pure virtualinherited
virtual void cv::ORB::setScaleFactor ( double  scaleFactor)
pure virtualinherited
virtual void cv::ORB::setScoreType ( int  scoreType)
pure virtualinherited
virtual void cv::ORB::setWTA_K ( int  wta_k)
pure virtualinherited
void cv::Feature2D::write ( const String fileName) const
inherited
virtual void cv::Feature2D::write ( FileStorage fs) const
virtualinherited

Stores algorithm parameters in a file storage.

Reimplemented from cv::Algorithm.

void cv::Algorithm::writeFormat ( FileStorage fs) const
protectedinherited

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