The class implements the modified H. More...

#include "calib3d.hpp"

Inheritance diagram for cv::StereoSGBM:

Collaboration diagram for cv::StereoSGBM:

Public Types
enum	{ DISP_SHIFT = 4, DISP_SCALE = (1 << DISP_SHIFT) }

enum	{ MODE_SGBM = 0, MODE_HH = 1, MODE_SGBM_3WAY = 2 }

Public Member Functions
virtual void	clear ()
	Clears the algorithm state. More...

virtual void	compute (InputArray left, InputArray right, OutputArray disparity)=0
	Computes disparity map for the specified stereo pair. More...

virtual bool	empty () const
	Returns true if the Algorithm is empty (e.g. More...

virtual int	getBlockSize () const =0

virtual String	getDefaultName () const
	Returns the algorithm string identifier. More...

virtual int	getDisp12MaxDiff () const =0

virtual int	getMinDisparity () const =0

virtual int	getMode () const =0

virtual int	getNumDisparities () const =0

virtual int	getP1 () const =0

virtual int	getP2 () const =0

virtual int	getPreFilterCap () const =0

virtual int	getSpeckleRange () const =0

virtual int	getSpeckleWindowSize () const =0

virtual int	getUniquenessRatio () const =0

virtual void	read (const FileNode &fn)
	Reads algorithm parameters from a file storage. More...

virtual void	save (const String &filename) const
	Saves the algorithm to a file. More...

virtual void	setBlockSize (int blockSize)=0

virtual void	setDisp12MaxDiff (int disp12MaxDiff)=0

virtual void	setMinDisparity (int minDisparity)=0

virtual void	setMode (int mode)=0

virtual void	setNumDisparities (int numDisparities)=0

virtual void	setP1 (int P1)=0

virtual void	setP2 (int P2)=0

virtual void	setPreFilterCap (int preFilterCap)=0

virtual void	setSpeckleRange (int speckleRange)=0

virtual void	setSpeckleWindowSize (int speckleWindowSize)=0

virtual void	setUniquenessRatio (int uniquenessRatio)=0

virtual void	write (FileStorage &fs) const
	Stores algorithm parameters in a file storage. More...

Static Public Member Functions
static Ptr< StereoSGBM >	create (int minDisparity, int numDisparities, int blockSize, int P1=0, int P2=0, int disp12MaxDiff=0, int preFilterCap=0, int uniquenessRatio=0, int speckleWindowSize=0, int speckleRange=0, int mode=StereoSGBM::MODE_SGBM)
	Creates StereoSGBM object. More...

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...

template<typename _Tp >
static Ptr< _Tp >	read (const FileNode &fn)
	Reads algorithm from the file node. More...

Protected Member Functions
void	writeFormat (FileStorage &fs) const

Detailed Description

The class implements the modified H.

Hirschmuller algorithm [39] that differs from the original one as follows:

By default, the algorithm is single-pass, which means that you consider only 5 directions instead of 8. Set mode=StereoSGBM::MODE_HH in createStereoSGBM to run the full variant of the algorithm but beware that it may consume a lot of memory.
The algorithm matches blocks, not individual pixels. Though, setting blockSize=1 reduces the blocks to single pixels.
Mutual information cost function is not implemented. Instead, a simpler Birchfield-Tomasi sub-pixel metric from [4] is used. Though, the color images are supported as well.
Some pre- and post- processing steps from K. Konolige algorithm StereoBM are included, for example: pre-filtering (StereoBM::PREFILTER_XSOBEL type) and post-filtering (uniqueness check, quadratic interpolation and speckle filtering).

Note

(Python) An example illustrating the use of the StereoSGBM matching algorithm can be found at opencv_source_code/samples/python/stereo_match.py

Member Enumeration Documentation

anonymous enum

inherited

Enumerator
DISP_SHIFT
DISP_SCALE

anonymous enum

Enumerator
MODE_SGBM
MODE_HH
MODE_SGBM_3WAY

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::StereoMatcher::compute	(	InputArray	left,
		InputArray	right,
		OutputArray	disparity
	)

pure virtualinherited

Computes disparity map for the specified stereo pair.

Parameters

left	Left 8-bit single-channel image.
right	Right image of the same size and the same type as the left one.
disparity	Output disparity map. It has the same size as the input images. Some algorithms, like StereoBM or StereoSGBM compute 16-bit fixed-point disparity map (where each disparity value has 4 fractional bits), whereas other algorithms output 32-bit floating-point disparity map.

static Ptr<StereoSGBM> cv::StereoSGBM::create	(	int	minDisparity,
		int	numDisparities,
		int	blockSize,
		int	P1 = `0`,
		int	P2 = `0`,
		int	disp12MaxDiff = `0`,
		int	preFilterCap = `0`,
		int	uniquenessRatio = `0`,
		int	speckleWindowSize = `0`,
		int	speckleRange = `0`,
		int	mode = `StereoSGBM::MODE_SGBM`
	)

static

Creates StereoSGBM object.

Parameters

minDisparity	Minimum possible disparity value. Normally, it is zero but sometimes rectification algorithms can shift images, so this parameter needs to be adjusted accordingly.
numDisparities	Maximum disparity minus minimum disparity. The value is always greater than zero. In the current implementation, this parameter must be divisible by 16.
blockSize	Matched block size. It must be an odd number >=1 . Normally, it should be somewhere in the 3..11 range.
P1	The first parameter controlling the disparity smoothness. See below.
P2	The second parameter controlling the disparity smoothness. The larger the values are, the smoother the disparity is. P1 is the penalty on the disparity change by plus or minus 1 between neighbor pixels. P2 is the penalty on the disparity change by more than 1 between neighbor pixels. The algorithm requires P2 > P1 . See stereo_match.cpp sample where some reasonably good P1 and P2 values are shown (like 8number_of_image_channelsSADWindowSizeSADWindowSize and 32number_of_image_channelsSADWindowSizeSADWindowSize , respectively).
disp12MaxDiff	Maximum allowed difference (in integer pixel units) in the left-right disparity check. Set it to a non-positive value to disable the check.
preFilterCap	Truncation value for the prefiltered image pixels. The algorithm first computes x-derivative at each pixel and clips its value by [-preFilterCap, preFilterCap] interval. The result values are passed to the Birchfield-Tomasi pixel cost function.
uniquenessRatio	Margin in percentage by which the best (minimum) computed cost function value should "win" the second best value to consider the found match correct. Normally, a value within the 5-15 range is good enough.
speckleWindowSize	Maximum size of smooth disparity regions to consider their noise speckles and invalidate. Set it to 0 to disable speckle filtering. Otherwise, set it somewhere in the 50-200 range.
speckleRange	Maximum disparity variation within each connected component. If you do speckle filtering, set the parameter to a positive value, it will be implicitly multiplied by 16. Normally, 1 or 2 is good enough.
mode	Set it to StereoSGBM::MODE_HH to run the full-scale two-pass dynamic programming algorithm. It will consume O(WHnumDisparities) bytes, which is large for 640x480 stereo and huge for HD-size pictures. By default, it is set to false .

The first constructor initializes StereoSGBM with all the default parameters. So, you only have to set StereoSGBM::numDisparities at minimum. The second constructor enables you to set each parameter to a custom value.

virtual bool cv::Algorithm::empty ( ) const

inlinevirtualinherited

Returns true if the Algorithm is empty (e.g.

in the very beginning or after unsuccessful read

Reimplemented in cv::DescriptorMatcher, cv::ml::StatModel, cv::Feature2D, cv::BaseCascadeClassifier, and cv::cuda::DescriptorMatcher.

virtual int cv::StereoMatcher::getBlockSize ( ) const

pure virtualinherited

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::StereoMatcher::getDisp12MaxDiff ( ) const

pure virtualinherited

virtual int cv::StereoMatcher::getMinDisparity ( ) const

pure virtualinherited

virtual int cv::StereoSGBM::getMode ( ) const

pure virtual

virtual int cv::StereoMatcher::getNumDisparities ( ) const

pure virtualinherited

virtual int cv::StereoSGBM::getP1 ( ) const

pure virtual

virtual int cv::StereoSGBM::getP2 ( ) const

pure virtual

virtual int cv::StereoSGBM::getPreFilterCap ( ) const

pure virtual

virtual int cv::StereoMatcher::getSpeckleRange ( ) const

pure virtualinherited

virtual int cv::StereoMatcher::getSpeckleWindowSize ( ) const

pure virtualinherited

virtual int cv::StereoSGBM::getUniquenessRatio ( ) const

pure virtual

template<typename _Tp >

static Ptr<_Tp> cv::Algorithm::load	(	const String &	filename,
		const String &	objname = `String()`
	)

inlinestaticinherited

Loads algorithm from the file.

Parameters

filename	Name of the file to read.
objname	The 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

strModel	The string variable containing the model you want to load.
objname	The 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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virtual void cv::Algorithm::read ( const FileNode & fn )

inlinevirtualinherited

Reads algorithm parameters from a file storage.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::Feature2D.

template<typename _Tp >

static Ptr<_Tp> cv::Algorithm::read ( const FileNode & fn )

inlinestaticinherited

Reads algorithm from the file node.

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

cv::FileStorage fsRead("example.xml", FileStorage::READ);

Ptr<SVM> svm = Algorithm::read<SVM>(fsRead.root());

In order to make this method work, the derived class must overwrite Algorithm::read(const FileNode& fn) and also have static create() method without parameters (or with all the optional parameters)

References cv::Ptr< T >::empty().

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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::StereoMatcher::setBlockSize ( int blockSize )

pure virtualinherited

virtual void cv::StereoMatcher::setDisp12MaxDiff ( int disp12MaxDiff )

pure virtualinherited

virtual void cv::StereoMatcher::setMinDisparity ( int minDisparity )

pure virtualinherited

virtual void cv::StereoSGBM::setMode ( int mode )

pure virtual

virtual void cv::StereoMatcher::setNumDisparities ( int numDisparities )

pure virtualinherited

virtual void cv::StereoSGBM::setP1 ( int P1 )

pure virtual

virtual void cv::StereoSGBM::setP2 ( int P2 )

pure virtual

virtual void cv::StereoSGBM::setPreFilterCap ( int preFilterCap )

pure virtual

virtual void cv::StereoMatcher::setSpeckleRange ( int speckleRange )

pure virtualinherited

virtual void cv::StereoMatcher::setSpeckleWindowSize ( int speckleWindowSize )

pure virtualinherited

virtual void cv::StereoSGBM::setUniquenessRatio ( int uniquenessRatio )

pure virtual

virtual void cv::Algorithm::write ( FileStorage & fs ) const

inlinevirtualinherited

Stores algorithm parameters in a file storage.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::Feature2D.

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

protectedinherited

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

calib3d/include/opencv2/calib3d.hpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

Member Function Documentation