Class used for calculation sparse optical flow and feature tracking with robust local optical flow (RLOF) algorithms. More...

#include <opencv2/optflow/rlofflow.hpp>

Collaboration diagram for cv::optflow::SparseRLOFOpticalFlow:

Public Member Functions
virtual float	getForwardBackward () const =0
	Threshold for the forward backward confidence check.

virtual Ptr< RLOFOpticalFlowParameter >	getRLOFOpticalFlowParameter () const =0
	Configuration of the RLOF alogrithm.

virtual void	setForwardBackward (float val)=0
	Threshold for the forward backward confidence check.

virtual void	setRLOFOpticalFlowParameter (Ptr< RLOFOpticalFlowParameter > val)=0
	Configuration of the RLOF alogrithm.

Public Member Functions inherited from cv::SparseOpticalFlow
virtual void	calc (InputArray prevImg, InputArray nextImg, InputArray prevPts, InputOutputArray nextPts, OutputArray status, OutputArray err=cv::noArray())=0
	Calculates a sparse optical flow.

Public Member Functions inherited from cv::Algorithm
	Algorithm ()

virtual	~Algorithm ()

virtual void	clear ()
	Clears the algorithm state.

virtual bool	empty () const
	Returns true if the Algorithm is empty (e.g. in the very beginning or after unsuccessful read.

virtual String	getDefaultName () const

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

virtual void	save (const String &filename) const

void	write (const Ptr< FileStorage > &fs, const String &name=String()) const

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

void	write (FileStorage &fs, const String &name) const

Static Public Member Functions
static Ptr< SparseRLOFOpticalFlow >	create (Ptr< RLOFOpticalFlowParameter > rlofParam=Ptr< RLOFOpticalFlowParameter >(), float forwardBackwardThreshold=1.f)
	Creates instance of SparseRLOFOpticalFlow.

Static Public Member Functions inherited from cv::Algorithm
template<typename _Tp >
static Ptr< _Tp >	load (const String &filename, const String &objname=String())
	Loads algorithm from the file.

template<typename _Tp >
static Ptr< _Tp >	loadFromString (const String &strModel, const String &objname=String())
	Loads algorithm from a String.

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

Additional Inherited Members
Protected Member Functions inherited from cv::Algorithm
void	writeFormat (FileStorage &fs) const

Detailed Description

Class used for calculation sparse optical flow and feature tracking with robust local optical flow (RLOF) algorithms.

The RLOF is a fast local optical flow approach described in [238] [239] [240] and [241] similar to the pyramidal iterative Lucas-Kanade method as proposed by [36]. More details and experiments can be found in the following thesis [242]. The implementation is derived from optflow::calcOpticalFlowPyrLK().

For the RLOF configuration see optflow::RLOFOpticalFlowParameter for further details. Parameters have been described in [238], [239], [240] and [241].

Note: SIMD parallelization is only available when compiling with SSE4.1.

See also: optflow::calcOpticalFlowSparseRLOF(), optflow::RLOFOpticalFlowParameter

Member Function Documentation

◆ create()

static Ptr< SparseRLOFOpticalFlow > cv::optflow::SparseRLOFOpticalFlow::create	(	Ptr< RLOFOpticalFlowParameter >	rlofParam = `Ptr< RLOFOpticalFlowParameter >()`,
		float	forwardBackwardThreshold = `1.f`
	)

static

Python:
	cv.optflow.SparseRLOFOpticalFlow.create(	[, rlofParam[, forwardBackwardThreshold]]	) ->	retval
	cv.optflow.SparseRLOFOpticalFlow_create(	[, rlofParam[, forwardBackwardThreshold]]	) ->	retval

Creates instance of SparseRLOFOpticalFlow.

Parameters

rlofParam	see setRLOFOpticalFlowParameter
forwardBackwardThreshold	see setForwardBackward

◆ getForwardBackward()

virtual float cv::optflow::SparseRLOFOpticalFlow::getForwardBackward ( ) const

pure virtual

Python:
	cv.optflow.SparseRLOFOpticalFlow.getForwardBackward(		) ->	retval

Threshold for the forward backward confidence check.

See also: setForwardBackward

◆ getRLOFOpticalFlowParameter()

virtual Ptr< RLOFOpticalFlowParameter > cv::optflow::SparseRLOFOpticalFlow::getRLOFOpticalFlowParameter ( ) const

pure virtual

Python:
	cv.optflow.SparseRLOFOpticalFlow.getRLOFOpticalFlowParameter(		) ->	retval

Configuration of the RLOF alogrithm.

See also: setRLOFOpticalFlowParameter

◆ setForwardBackward()

virtual void cv::optflow::SparseRLOFOpticalFlow::setForwardBackward ( float val )

pure virtual

Python:
	cv.optflow.SparseRLOFOpticalFlow.setForwardBackward(	val	) ->	None

Threshold for the forward backward confidence check.

For each feature point a motion vector \( d_{I0,I1}(\mathbf{x}) \) is computed. If the forward backward error

\[ EP_{FB} = || d_{I0,I1} + d_{I1,I0} || \]

is larger than threshold given by this function then the status will not be used by the following vector field interpolation. \( d_{I1,I0} \) denotes the backward flow. Note, the forward backward test will only be applied if the threshold > 0. This may results into a doubled runtime for the motion estimation.