Merge pull request #710 from VladX:optflow
commit
dd9b2eb4fb
8 changed files with 1401 additions and 3 deletions
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/*
|
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By downloading, copying, installing or using the software you agree to this |
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license. If you do not agree to this license, do not download, install, |
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copy or use the software. |
||||
|
||||
|
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License Agreement |
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For Open Source Computer Vision Library |
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(3-clause BSD License) |
||||
|
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Copyright (C) 2016, OpenCV Foundation, all rights reserved. |
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Third party copyrights are property of their respective owners. |
||||
|
||||
Redistribution and use in source and binary forms, with or without modification, |
||||
are permitted provided that the following conditions are met: |
||||
|
||||
* Redistributions of source code must retain the above copyright notice, |
||||
this list of conditions and the following disclaimer. |
||||
|
||||
* Redistributions in binary form must reproduce the above copyright notice, |
||||
this list of conditions and the following disclaimer in the documentation |
||||
and/or other materials provided with the distribution. |
||||
|
||||
* Neither the names of the copyright holders nor the names of the contributors |
||||
may be used to endorse or promote products derived from this software |
||||
without specific prior written permission. |
||||
|
||||
This software is provided by the copyright holders and contributors "as is" and |
||||
any express or implied warranties, including, but not limited to, the implied |
||||
warranties of merchantability and fitness for a particular purpose are |
||||
disclaimed. In no event shall copyright holders or contributors be liable for |
||||
any direct, indirect, incidental, special, exemplary, or consequential damages |
||||
(including, but not limited to, procurement of substitute goods or services; |
||||
loss of use, data, or profits; or business interruption) however caused |
||||
and on any theory of liability, whether in contract, strict liability, |
||||
or tort (including negligence or otherwise) arising in any way out of |
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the use of this software, even if advised of the possibility of such damage. |
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*/ |
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|
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/*
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Implementation of the PCAFlow algorithm from the following paper: |
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http://files.is.tue.mpg.de/black/papers/cvpr2015_pcaflow.pdf
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@inproceedings{Wulff:CVPR:2015, |
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title = {Efficient Sparse-to-Dense Optical Flow Estimation using a Learned Basis and Layers}, |
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author = {Wulff, Jonas and Black, Michael J.}, |
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booktitle = { IEEE Conf. on Computer Vision and Pattern Recognition (CVPR) 2015}, |
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month = jun, |
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year = {2015} |
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} |
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There are some key differences which distinguish this algorithm from the original PCAFlow (see paper): |
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- Discrete Cosine Transform basis is used instead of basis extracted with PCA. |
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Reasoning: DCT basis has comparable performance and it doesn't require additional storage space. |
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Also, this decision helps to avoid overloading the algorithm with a lot of external input. |
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- Usage of built-in OpenCV feature tracking instead of libviso. |
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*/ |
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#ifndef __OPENCV_OPTFLOW_PCAFLOW_HPP__ |
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#define __OPENCV_OPTFLOW_PCAFLOW_HPP__ |
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#include "opencv2/core.hpp" |
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#include "opencv2/video.hpp" |
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namespace cv |
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{ |
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namespace optflow |
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{ |
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/*
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* This class can be used for imposing a learned prior on the resulting optical flow. |
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* Solution will be regularized according to this prior. |
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* You need to generate appropriate prior file with "learn_prior.py" script beforehand. |
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*/ |
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class CV_EXPORTS_W PCAPrior |
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{ |
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private: |
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Mat L1; |
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Mat L2; |
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Mat c1; |
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Mat c2; |
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public: |
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PCAPrior( const char *pathToPrior ); |
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int getPadding() const { return L1.size().height; } |
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int getBasisSize() const { return L1.size().width; } |
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void fillConstraints( float *A1, float *A2, float *b1, float *b2 ) const; |
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}; |
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class CV_EXPORTS_W OpticalFlowPCAFlow : public DenseOpticalFlow |
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{ |
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protected: |
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const Ptr<const PCAPrior> prior; |
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const Size basisSize; |
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const float sparseRate; // (0 .. 0.1)
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const float retainedCornersFraction; // [0 .. 1]
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const float occlusionsThreshold; |
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const float dampingFactor; |
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const float claheClip; |
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bool useOpenCL; |
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public: |
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OpticalFlowPCAFlow( Ptr<const PCAPrior> _prior = Ptr<const PCAPrior>(), const Size _basisSize = Size( 18, 14 ), |
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float _sparseRate = 0.024, float _retainedCornersFraction = 0.2, |
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float _occlusionsThreshold = 0.0003, float _dampingFactor = 0.00002, float _claheClip = 14 ); |
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void calc( InputArray I0, InputArray I1, InputOutputArray flow ); |
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void collectGarbage(); |
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private: |
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void findSparseFeatures( UMat &from, UMat &to, std::vector<Point2f> &features, |
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std::vector<Point2f> &predictedFeatures ) const; |
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void removeOcclusions( UMat &from, UMat &to, std::vector<Point2f> &features, |
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std::vector<Point2f> &predictedFeatures ) const; |
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void getSystem( OutputArray AOut, OutputArray b1Out, OutputArray b2Out, const std::vector<Point2f> &features, |
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const std::vector<Point2f> &predictedFeatures, const Size size ); |
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void getSystem( OutputArray A1Out, OutputArray A2Out, OutputArray b1Out, OutputArray b2Out, |
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const std::vector<Point2f> &features, const std::vector<Point2f> &predictedFeatures, |
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const Size size ); |
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OpticalFlowPCAFlow& operator=( const OpticalFlowPCAFlow& ); // make it non-assignable
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}; |
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CV_EXPORTS_W Ptr<DenseOpticalFlow> createOptFlow_PCAFlow(); |
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} |
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} |
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#endif |
@ -0,0 +1,184 @@ |
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/*
|
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By downloading, copying, installing or using the software you agree to this |
||||
license. If you do not agree to this license, do not download, install, |
||||
copy or use the software. |
||||
|
||||
|
||||
License Agreement |
||||
For Open Source Computer Vision Library |
||||
(3-clause BSD License) |
||||
|
||||
Copyright (C) 2016, OpenCV Foundation, all rights reserved. |
||||
Third party copyrights are property of their respective owners. |
||||
|
||||
Redistribution and use in source and binary forms, with or without modification, |
||||
are permitted provided that the following conditions are met: |
||||
|
||||
* Redistributions of source code must retain the above copyright notice, |
||||
this list of conditions and the following disclaimer. |
||||
|
||||
* Redistributions in binary form must reproduce the above copyright notice, |
||||
this list of conditions and the following disclaimer in the documentation |
||||
and/or other materials provided with the distribution. |
||||
|
||||
* Neither the names of the copyright holders nor the names of the contributors |
||||
may be used to endorse or promote products derived from this software |
||||
without specific prior written permission. |
||||
|
||||
This software is provided by the copyright holders and contributors "as is" and |
||||
any express or implied warranties, including, but not limited to, the implied |
||||
warranties of merchantability and fitness for a particular purpose are |
||||
disclaimed. In no event shall copyright holders or contributors be liable for |
||||
any direct, indirect, incidental, special, exemplary, or consequential damages |
||||
(including, but not limited to, procurement of substitute goods or services; |
||||
loss of use, data, or profits; or business interruption) however caused |
||||
and on any theory of liability, whether in contract, strict liability, |
||||
or tort (including negligence or otherwise) arising in any way out of |
||||
the use of this software, even if advised of the possibility of such damage. |
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*/ |
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|
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/*
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Implementation of the Global Patch Collider algorithm from the following paper: |
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http://research.microsoft.com/en-us/um/people/pkohli/papers/wfrik_cvpr2016.pdf
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@InProceedings{Wang_2016_CVPR, |
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author = {Wang, Shenlong and Ryan Fanello, Sean and Rhemann, Christoph and Izadi, Shahram and Kohli, Pushmeet}, |
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title = {The Global Patch Collider}, |
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booktitle = {The IEEE Conference on Computer Vision and Pattern Recognition (CVPR)}, |
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month = {June}, |
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year = {2016} |
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} |
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*/ |
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#ifndef __OPENCV_OPTFLOW_SPARSE_MATCHING_GPC_HPP__ |
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#define __OPENCV_OPTFLOW_SPARSE_MATCHING_GPC_HPP__ |
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#include "opencv2/core.hpp" |
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namespace cv |
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{ |
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namespace optflow |
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{ |
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struct CV_EXPORTS_W GPCPatchDescriptor |
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{ |
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static const unsigned nFeatures = 18; // number of features in a patch descriptor
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Vec< double, nFeatures > feature; |
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GPCPatchDescriptor( const Mat *imgCh, int i, int j ); |
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}; |
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typedef std::pair< GPCPatchDescriptor, GPCPatchDescriptor > GPCPatchSample; |
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typedef std::vector< GPCPatchSample > GPCSamplesVector; |
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/** @brief Class encapsulating training samples.
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*/ |
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class CV_EXPORTS_W GPCTrainingSamples |
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{ |
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private: |
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GPCSamplesVector samples; |
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public: |
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/** @brief This function can be used to extract samples from a pair of images and a ground truth flow.
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* Sizes of all the provided vectors must be equal. |
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*/ |
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static Ptr< GPCTrainingSamples > create( const std::vector< String > &imagesFrom, const std::vector< String > &imagesTo, |
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const std::vector< String > > ); |
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size_t size() const { return samples.size(); } |
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operator GPCSamplesVector() const { return samples; } |
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operator GPCSamplesVector &() { return samples; } |
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}; |
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class CV_EXPORTS_W GPCTree : public Algorithm |
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{ |
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public: |
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struct Node |
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{ |
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Vec< double, GPCPatchDescriptor::nFeatures > coef; // hyperplane coefficients
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double rhs; |
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unsigned left; |
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unsigned right; |
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bool operator==( const Node &n ) const { return coef == n.coef && rhs == n.rhs && left == n.left && right == n.right; } |
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}; |
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private: |
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typedef GPCSamplesVector::iterator SIter; |
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std::vector< Node > nodes; |
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bool trainNode( size_t nodeId, SIter begin, SIter end, unsigned depth ); |
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public: |
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void train( GPCSamplesVector &samples ); |
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void write( FileStorage &fs ) const; |
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void read( const FileNode &fn ); |
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static Ptr< GPCTree > create() { return makePtr< GPCTree >(); } |
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bool operator==( const GPCTree &t ) const { return nodes == t.nodes; } |
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}; |
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template < int T > class CV_EXPORTS_W GPCForest : public Algorithm |
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{ |
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private: |
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GPCTree tree[T]; |
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public: |
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/** @brief Train the forest using one sample set for every tree.
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* Please, consider using the next method instead of this one for better quality. |
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*/ |
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void train( GPCSamplesVector &samples ) |
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{ |
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for ( int i = 0; i < T; ++i ) |
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tree[i].train( samples ); |
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} |
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/** @brief Train the forest using individual samples for each tree.
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* It is generally better to use this instead of the first method. |
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*/ |
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void train( const std::vector< String > &imagesFrom, const std::vector< String > &imagesTo, const std::vector< String > > ) |
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{ |
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for ( int i = 0; i < T; ++i ) |
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{ |
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Ptr< GPCTrainingSamples > samples = GPCTrainingSamples::create( imagesFrom, imagesTo, gt ); // Create training set for the tree
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tree[i].train( *samples ); |
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} |
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} |
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void write( FileStorage &fs ) const |
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{ |
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fs << "ntrees" << T << "trees" |
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<< "["; |
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for ( int i = 0; i < T; ++i ) |
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{ |
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fs << "{"; |
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tree[i].write( fs ); |
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fs << "}"; |
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} |
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fs << "]"; |
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} |
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void read( const FileNode &fn ) |
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{ |
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CV_Assert( T == (int)fn["ntrees"] ); |
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FileNodeIterator it = fn["trees"].begin(); |
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for ( int i = 0; i < T; ++i, ++it ) |
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tree[i].read( *it ); |
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} |
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static Ptr< GPCForest > create() { return makePtr< GPCForest >(); } |
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}; |
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} |
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CV_EXPORTS void write( FileStorage &fs, const String &name, const optflow::GPCTree::Node &node ); |
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CV_EXPORTS void read( const FileNode &fn, optflow::GPCTree::Node &node, optflow::GPCTree::Node ); |
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} |
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#endif |
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#include "opencv2/optflow.hpp" |
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#include <iostream> |
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const int nTrees = 5; |
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int main( int argc, const char **argv ) |
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{ |
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int nSequences = argc - 1; |
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if ( nSequences <= 0 || nSequences % 3 != 0 ) |
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{ |
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std::cerr << "Usage: " << argv[0] << " ImageFrom1 ImageTo1 GroundTruth1 ... ImageFromN ImageToN GroundTruthN" << std::endl; |
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return 1; |
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} |
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nSequences /= 3; |
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std::vector< cv::String > img1, img2, gt; |
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for ( int i = 0; i < nSequences; ++i ) |
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{ |
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img1.push_back( argv[1 + i * 3] ); |
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img2.push_back( argv[1 + i * 3 + 1] ); |
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gt.push_back( argv[1 + i * 3 + 2] ); |
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} |
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cv::Ptr< cv::optflow::GPCForest< nTrees > > forest = cv::optflow::GPCForest< nTrees >::create(); |
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forest->train( img1, img2, gt ); |
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forest->save( "forest.dump" ); |
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return 0; |
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} |
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#!/usr/bin/env python |
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import os |
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import sys |
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import numpy as np |
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import cv2 |
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import struct |
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import argparse |
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from math import sqrt |
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argparser = argparse.ArgumentParser( |
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description='''Use this script to generate prior for using with PCAFlow. |
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Basis size here must match corresponding parameter in the PCAFlow. |
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Gamma should be selected experimentally.''') |
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argparser.add_argument('-f', |
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'--files', |
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nargs='+', |
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help='List of optical flow .flo files for learning. You can pass a directory here and it will be scanned recursively for .flo files.', |
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required=True) |
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argparser.add_argument('-o', |
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'--output', |
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help='Output file for prior', |
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required=True) |
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argparser.add_argument('--width', |
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type=int, |
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help='Size of the basis first dimension', |
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required=True, |
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default=18) |
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argparser.add_argument('--height', |
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type=int, |
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help='Size of the basis second dimension', |
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required=True, |
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default=14) |
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argparser.add_argument( |
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'-g', |
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'--gamma', |
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type=float, |
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help='Amount of regularization. The greater this parameter, the bigger will be an impact of the regularization.', |
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required=True) |
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args = argparser.parse_args() |
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basis_size = (args.height, args.width) |
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gamma = args.gamma |
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def find_flo(pp): |
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f = [] |
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for p in pp: |
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if os.path.isfile(p): |
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f.append(p) |
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else: |
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for root, subdirs, files in os.walk(p): |
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f += map(lambda x: os.path.join(root, x), |
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filter(lambda x: x.split('.')[-1] == 'flo', files)) |
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return list(set(f)) |
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|
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def load_flo(flo): |
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with open(flo, 'rb') as f: |
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magic = np.fromfile(f, np.float32, count=1)[0] |
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if 202021.25 != magic: |
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print('Magic number incorrect. Invalid .flo file') |
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else: |
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w = np.fromfile(f, np.int32, count=1)[0] |
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h = np.fromfile(f, np.int32, count=1)[0] |
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print('Reading %dx%d flo file %s' % (w, h, flo)) |
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data = np.fromfile(f, np.float32, count=2 * w * h) |
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# Reshape data into 3D array (columns, rows, bands) |
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flow = np.reshape(data, (h, w, 2)) |
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return flow[:, :, 0], flow[:, :, 1] |
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|
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|
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def get_w(m): |
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s = m.shape |
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w = cv2.dct(m) |
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w *= 2.0 / sqrt(s[0] * s[1]) |
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#w[0,0] *= 0.5 |
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w[:, 0] *= sqrt(0.5) |
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w[0, :] *= sqrt(0.5) |
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w = w[0:basis_size[0], 0:basis_size[1]].transpose().flatten() |
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return w |
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|
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|
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w1 = [] |
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w2 = [] |
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|
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for flo in find_flo(args.files): |
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x, y = load_flo(flo) |
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w1.append(get_w(x)) |
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w2.append(get_w(y)) |
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w1mean = sum(w1) / len(w1) |
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w2mean = sum(w2) / len(w2) |
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|
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for i in xrange(len(w1)): |
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w1[i] -= w1mean |
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for i in xrange(len(w2)): |
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w2[i] -= w2mean |
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|
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Q1 = sum([w1[i].reshape(-1, 1).dot(w1[i].reshape(1, -1)) |
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for i in xrange(len(w1))]) / len(w1) |
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Q2 = sum([w2[i].reshape(-1, 1).dot(w2[i].reshape(1, -1)) |
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for i in xrange(len(w2))]) / len(w2) |
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Q1 = np.matrix(Q1) |
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Q2 = np.matrix(Q2) |
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|
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if len(w1) > 1: |
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while True: |
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try: |
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L1 = np.linalg.cholesky(Q1) |
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break |
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except np.linalg.linalg.LinAlgError: |
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mev = min(np.linalg.eig(Q1)[0]).real |
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assert (mev < 0) |
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print('Q1', mev) |
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if -mev < 1e-6: |
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mev = -1e-6 |
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Q1 += (-mev * 1.000001) * np.identity(Q1.shape[0]) |
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|
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while True: |
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try: |
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L2 = np.linalg.cholesky(Q2) |
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break |
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except np.linalg.linalg.LinAlgError: |
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mev = min(np.linalg.eig(Q2)[0]).real |
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assert (mev < 0) |
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print('Q2', mev) |
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if -mev < 1e-6: |
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mev = -1e-6 |
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Q2 += (-mev * 1.000001) * np.identity(Q2.shape[0]) |
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else: |
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L1 = np.identity(Q1.shape[0]) |
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L2 = np.identity(Q2.shape[0]) |
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|
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L1 = np.linalg.inv(L1) * gamma |
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L2 = np.linalg.inv(L2) * gamma |
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|
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assert (L1.shape == L2.shape) |
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assert (L1.shape[0] == L1.shape[1]) |
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|
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f = open(args.output, 'wb') |
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|
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f.write(struct.pack('I', L1.shape[0])) |
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f.write(struct.pack('I', L1.shape[1])) |
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|
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for i in xrange(L1.shape[0]): |
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for j in xrange(L1.shape[1]): |
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f.write(struct.pack('f', L1[i, j])) |
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|
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for i in xrange(L2.shape[0]): |
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for j in xrange(L2.shape[1]): |
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f.write(struct.pack('f', L2[i, j])) |
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|
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b1 = L1.dot(w1mean.reshape(-1, 1)) |
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b2 = L2.dot(w2mean.reshape(-1, 1)) |
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|
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assert (L1.shape[0] == b1.shape[0]) |
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|
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for i in xrange(b1.shape[0]): |
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f.write(struct.pack('f', b1[i, 0])) |
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|
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for i in xrange(b2.shape[0]): |
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f.write(struct.pack('f', b2[i, 0])) |
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|
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f.close() |
@ -0,0 +1,526 @@ |
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/*M///////////////////////////////////////////////////////////////////////////////////////
|
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//
|
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// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
|
||||
//
|
||||
// By downloading, copying, installing or using the software you agree to this license.
|
||||
// If you do not agree to this license, do not download, install,
|
||||
// copy or use the software.
|
||||
//
|
||||
//
|
||||
// License Agreement
|
||||
// For Open Source Computer Vision Library
|
||||
//
|
||||
// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
|
||||
// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
|
||||
// Third party copyrights are property of their respective owners.
|
||||
//
|
||||
// Redistribution and use in source and binary forms, with or without modification,
|
||||
// are permitted provided that the following conditions are met:
|
||||
//
|
||||
// * Redistribution's of source code must retain the above copyright notice,
|
||||
// this list of conditions and the following disclaimer.
|
||||
//
|
||||
// * Redistribution's in binary form must reproduce the above copyright notice,
|
||||
// this list of conditions and the following disclaimer in the documentation
|
||||
// and/or other materials provided with the distribution.
|
||||
//
|
||||
// * The name of the copyright holders may not be used to endorse or promote products
|
||||
// derived from this software without specific prior written permission.
|
||||
//
|
||||
// This software is provided by the copyright holders and contributors "as is" and
|
||||
// any express or implied warranties, including, but not limited to, the implied
|
||||
// warranties of merchantability and fitness for a particular purpose are disclaimed.
|
||||
// In no event shall the Intel Corporation or contributors be liable for any direct,
|
||||
// indirect, incidental, special, exemplary, or consequential damages
|
||||
// (including, but not limited to, procurement of substitute goods or services;
|
||||
// loss of use, data, or profits; or business interruption) however caused
|
||||
// and on any theory of liability, whether in contract, strict liability,
|
||||
// or tort (including negligence or otherwise) arising in any way out of
|
||||
// the use of this software, even if advised of the possibility of such damage.
|
||||
//
|
||||
//M*/
|
||||
|
||||
#include "opencv2/ximgproc/edge_filter.hpp" |
||||
#include "precomp.hpp" |
||||
|
||||
/* Disable "from double to float" and "from size_t to int" warnings.
|
||||
* Fixing these would make the code look ugly by introducing explicit cast all around. |
||||
* Here these warning are pointless anyway. |
||||
*/ |
||||
#ifdef _MSC_VER |
||||
#pragma warning( disable : 4305 4244 4267 4838 ) |
||||
#endif |
||||
#ifdef __clang__ |
||||
#pragma clang diagnostic ignored "-Wshorten-64-to-32" |
||||
#endif |
||||
|
||||
namespace cv |
||||
{ |
||||
namespace optflow |
||||
{ |
||||
namespace |
||||
{ |
||||
|
||||
#ifndef M_SQRT2 |
||||
const float M_SQRT2 = 1.41421356237309504880; |
||||
#endif |
||||
|
||||
template <typename T> inline int mathSign( T val ) { return ( T( 0 ) < val ) - ( val < T( 0 ) ); } |
||||
|
||||
/* Stable symmetric Householder reflection that gives c and s such that
|
||||
* [ c s ][a] = [d], |
||||
* [ s -c ][b] [0] |
||||
* |
||||
* Output: |
||||
* c -- cosine(theta), where theta is the implicit angle of rotation |
||||
* (counter-clockwise) in a plane-rotation |
||||
* s -- sine(theta) |
||||
* r -- two-norm of [a; b] |
||||
*/ |
||||
inline void symOrtho( double a, double b, double &c, double &s, double &r ) |
||||
{ |
||||
if ( b == 0 ) |
||||
{ |
||||
c = mathSign( a ); |
||||
s = 0; |
||||
r = std::abs( a ); |
||||
} |
||||
else if ( a == 0 ) |
||||
{ |
||||
c = 0; |
||||
s = mathSign( b ); |
||||
r = std::abs( b ); |
||||
} |
||||
else if ( std::abs( b ) > std::abs( a ) ) |
||||
{ |
||||
const double tau = a / b; |
||||
s = mathSign( b ) / std::sqrt( 1 + tau * tau ); |
||||
c = s * tau; |
||||
r = b / s; |
||||
} |
||||
else |
||||
{ |
||||
const double tau = b / a; |
||||
c = mathSign( a ) / std::sqrt( 1 + tau * tau ); |
||||
s = c * tau; |
||||
r = a / c; |
||||
} |
||||
} |
||||
|
||||
/* Iterative LSQR algorithm for solving least squares problems.
|
||||
* |
||||
* [1] Paige, C. C. and M. A. Saunders, |
||||
* LSQR: An Algorithm for Sparse Linear Equations And Sparse Least Squares |
||||
* ACM Trans. Math. Soft., Vol.8, 1982, pp. 43-71. |
||||
* |
||||
* Solves the following problem: |
||||
* argmin_x ||Ax - b|| + damp||x|| |
||||
* |
||||
* Output: |
||||
* x -- approximate solution |
||||
*/ |
||||
void solveLSQR( const Mat &A, const Mat &b, OutputArray xOut, const double damp = 0.0, const unsigned iter_lim = 10 ) |
||||
{ |
||||
const int n = A.size().width; |
||||
CV_Assert( A.size().height == b.size().height ); |
||||
CV_Assert( A.type() == CV_32F ); |
||||
CV_Assert( b.type() == CV_32F ); |
||||
xOut.create( n, 1, CV_32F ); |
||||
|
||||
Mat v( n, 1, CV_32F, 0.0f ); |
||||
Mat u = b; |
||||
Mat x = xOut.getMat(); |
||||
x = Mat::zeros( x.size(), x.type() ); |
||||
double alfa = 0; |
||||
double beta = cv::norm( u, NORM_L2 ); |
||||
Mat w( n, 1, CV_32F, 0.0f ); |
||||
const Mat AT = A.t(); |
||||
|
||||
if ( beta > 0 ) |
||||
{ |
||||
u *= 1 / beta; |
||||
v = AT * u; |
||||
alfa = cv::norm( v, NORM_L2 ); |
||||
} |
||||
|
||||
if ( alfa > 0 ) |
||||
{ |
||||
v *= 1 / alfa; |
||||
w = v.clone(); |
||||
} |
||||
|
||||
double rhobar = alfa; |
||||
double phibar = beta; |
||||
if ( alfa * beta == 0 ) |
||||
return; |
||||
|
||||
for ( unsigned itn = 0; itn < iter_lim; ++itn ) |
||||
{ |
||||
u *= -alfa; |
||||
u += A * v; |
||||
beta = cv::norm( u, NORM_L2 ); |
||||
|
||||
if ( beta > 0 ) |
||||
{ |
||||
u *= 1 / beta; |
||||
v *= -beta; |
||||
v += AT * u; |
||||
alfa = cv::norm( v, NORM_L2 ); |
||||
if ( alfa > 0 ) |
||||
v *= 1 / alfa; |
||||
} |
||||
|
||||
double rhobar1 = sqrt( rhobar * rhobar + damp * damp ); |
||||
double cs1 = rhobar / rhobar1; |
||||
phibar = cs1 * phibar; |
||||
|
||||
double cs, sn, rho; |
||||
symOrtho( rhobar1, beta, cs, sn, rho ); |
||||
|
||||
double theta = sn * alfa; |
||||
rhobar = -cs * alfa; |
||||
double phi = cs * phibar; |
||||
phibar = sn * phibar; |
||||
|
||||
double t1 = phi / rho; |
||||
double t2 = -theta / rho; |
||||
|
||||
x += t1 * w; |
||||
w *= t2; |
||||
w += v; |
||||
} |
||||
} |
||||
|
||||
inline void _cpu_fillDCTSampledPoints( float *row, const Point2f &p, const Size &basisSize, const Size &size ) |
||||
{ |
||||
for ( int n1 = 0; n1 < basisSize.width; ++n1 ) |
||||
for ( int n2 = 0; n2 < basisSize.height; ++n2 ) |
||||
row[n1 * basisSize.height + n2] = |
||||
cosf( ( n1 * CV_PI / size.width ) * ( p.x + 0.5 ) ) * cosf( ( n2 * CV_PI / size.height ) * ( p.y + 0.5 ) ); |
||||
} |
||||
|
||||
ocl::ProgramSource _ocl_fillDCTSampledPointsSource( |
||||
"__kernel void fillDCTSampledPoints(__global const uchar* features, int fstep, int foff, __global " |
||||
"uchar* A, int Astep, int Aoff, int fs, int bsw, int bsh, int sw, int sh) {" |
||||
"const int i = get_global_id(0);" |
||||
"const int n1 = get_global_id(1);" |
||||
"const int n2 = get_global_id(2);" |
||||
"if (i >= fs || n1 >= bsw || n2 >= bsh) return;" |
||||
"__global const float2* f = (__global const float2*)(features + (fstep * i + foff));" |
||||
"__global float* a = (__global float*)(A + (Astep * i + Aoff + (n1 * bsh + n2) * sizeof(float)));" |
||||
"const float2 p = f[0];" |
||||
"const float pi = 3.14159265358979323846;" |
||||
"a[0] = cos((n1 * pi / sw) * (p.x + 0.5)) * cos((n2 * pi / sh) * (p.y + 0.5));" |
||||
"}" ); |
||||
|
||||
void applyCLAHE( UMat &img, float claheClip ) |
||||
{ |
||||
Ptr<CLAHE> clahe = createCLAHE(); |
||||
clahe->setClipLimit( claheClip ); |
||||
clahe->apply( img, img ); |
||||
} |
||||
|
||||
void reduceToFlow( const Mat &w1, const Mat &w2, Mat &flow, const Size &basisSize ) |
||||
{ |
||||
const Size size = flow.size(); |
||||
Mat flowX( size, CV_32F, 0.0f ); |
||||
Mat flowY( size, CV_32F, 0.0f ); |
||||
|
||||
const float mult = sqrt( size.area() ) * 0.5; |
||||
|
||||
for ( int i = 0; i < basisSize.width; ++i ) |
||||
for ( int j = 0; j < basisSize.height; ++j ) |
||||
{ |
||||
flowX.at<float>( j, i ) = w1.at<float>( i * basisSize.height + j ) * mult; |
||||
flowY.at<float>( j, i ) = w2.at<float>( i * basisSize.height + j ) * mult; |
||||
} |
||||
for ( int i = 0; i < basisSize.height; ++i ) |
||||
{ |
||||
flowX.at<float>( i, 0 ) *= M_SQRT2; |
||||
flowY.at<float>( i, 0 ) *= M_SQRT2; |
||||
} |
||||
for ( int i = 0; i < basisSize.width; ++i ) |
||||
{ |
||||
flowX.at<float>( 0, i ) *= M_SQRT2; |
||||
flowY.at<float>( 0, i ) *= M_SQRT2; |
||||
} |
||||
|
||||
dct( flowX, flowX, DCT_INVERSE ); |
||||
dct( flowY, flowY, DCT_INVERSE ); |
||||
for ( int i = 0; i < size.height; ++i ) |
||||
for ( int j = 0; j < size.width; ++j ) |
||||
flow.at<Point2f>( i, j ) = Point2f( flowX.at<float>( i, j ), flowY.at<float>( i, j ) ); |
||||
} |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::findSparseFeatures( UMat &from, UMat &to, std::vector<Point2f> &features, |
||||
std::vector<Point2f> &predictedFeatures ) const |
||||
{ |
||||
Size size = from.size(); |
||||
const unsigned maxFeatures = size.area() * sparseRate; |
||||
goodFeaturesToTrack( from, features, maxFeatures * retainedCornersFraction, 0.005, 3 ); |
||||
|
||||
// Add points along the grid if not enough features
|
||||
if ( maxFeatures > features.size() ) |
||||
{ |
||||
const unsigned missingPoints = maxFeatures - features.size(); |
||||
const unsigned blockSize = sqrt( (float)size.area() / missingPoints ); |
||||
for ( int x = blockSize / 2; x < size.width; x += blockSize ) |
||||
for ( int y = blockSize / 2; y < size.height; y += blockSize ) |
||||
features.push_back( Point2f( x, y ) ); |
||||
} |
||||
std::vector<uchar> predictedStatus; |
||||
std::vector<float> predictedError; |
||||
calcOpticalFlowPyrLK( from, to, features, predictedFeatures, predictedStatus, predictedError ); |
||||
|
||||
size_t j = 0; |
||||
for ( size_t i = 0; i < features.size(); ++i ) |
||||
{ |
||||
if ( predictedStatus[i] ) |
||||
{ |
||||
features[j] = features[i]; |
||||
predictedFeatures[j] = predictedFeatures[i]; |
||||
++j; |
||||
} |
||||
} |
||||
features.resize( j ); |
||||
predictedFeatures.resize( j ); |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::removeOcclusions( UMat &from, UMat &to, std::vector<Point2f> &features, |
||||
std::vector<Point2f> &predictedFeatures ) const |
||||
{ |
||||
std::vector<uchar> predictedStatus; |
||||
std::vector<float> predictedError; |
||||
std::vector<Point2f> backwardFeatures; |
||||
calcOpticalFlowPyrLK( to, from, predictedFeatures, backwardFeatures, predictedStatus, predictedError ); |
||||
|
||||
size_t j = 0; |
||||
const float threshold = occlusionsThreshold * sqrt( from.size().area() ); |
||||
for ( size_t i = 0; i < predictedFeatures.size(); ++i ) |
||||
{ |
||||
if ( predictedStatus[i] ) |
||||
{ |
||||
Point2f flowDiff = features[i] - backwardFeatures[i]; |
||||
if ( flowDiff.dot( flowDiff ) <= threshold ) |
||||
{ |
||||
features[j] = features[i]; |
||||
predictedFeatures[j] = predictedFeatures[i]; |
||||
++j; |
||||
} |
||||
} |
||||
} |
||||
features.resize( j ); |
||||
predictedFeatures.resize( j ); |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::getSystem( OutputArray AOut, OutputArray b1Out, OutputArray b2Out, |
||||
const std::vector<Point2f> &features, const std::vector<Point2f> &predictedFeatures, |
||||
const Size size ) |
||||
{ |
||||
AOut.create( features.size(), basisSize.area(), CV_32F ); |
||||
b1Out.create( features.size(), 1, CV_32F ); |
||||
b2Out.create( features.size(), 1, CV_32F ); |
||||
if ( useOpenCL ) |
||||
{ |
||||
UMat A = AOut.getUMat(); |
||||
Mat b1 = b1Out.getMat(); |
||||
Mat b2 = b2Out.getMat(); |
||||
|
||||
ocl::Kernel kernel( "fillDCTSampledPoints", _ocl_fillDCTSampledPointsSource ); |
||||
size_t globSize[] = {features.size(), basisSize.width, basisSize.height}; |
||||
kernel |
||||
.args( cv::ocl::KernelArg::ReadOnlyNoSize( Mat( features ).getUMat( ACCESS_READ ) ), |
||||
cv::ocl::KernelArg::WriteOnlyNoSize( A ), (int)features.size(), (int)basisSize.width, |
||||
(int)basisSize.height, (int)size.width, (int)size.height ) |
||||
.run( 3, globSize, 0, true ); |
||||
|
||||
for ( size_t i = 0; i < features.size(); ++i ) |
||||
{ |
||||
const Point2f flow = predictedFeatures[i] - features[i]; |
||||
b1.at<float>( i ) = flow.x; |
||||
b2.at<float>( i ) = flow.y; |
||||
} |
||||
} |
||||
else |
||||
{ |
||||
Mat A = AOut.getMat(); |
||||
Mat b1 = b1Out.getMat(); |
||||
Mat b2 = b2Out.getMat(); |
||||
|
||||
for ( size_t i = 0; i < features.size(); ++i ) |
||||
{ |
||||
_cpu_fillDCTSampledPoints( A.ptr<float>( i ), features[i], basisSize, size ); |
||||
const Point2f flow = predictedFeatures[i] - features[i]; |
||||
b1.at<float>( i ) = flow.x; |
||||
b2.at<float>( i ) = flow.y; |
||||
} |
||||
} |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::getSystem( OutputArray A1Out, OutputArray A2Out, OutputArray b1Out, OutputArray b2Out, |
||||
const std::vector<Point2f> &features, const std::vector<Point2f> &predictedFeatures, |
||||
const Size size ) |
||||
{ |
||||
CV_Assert( prior->getBasisSize() == basisSize.area() ); |
||||
|
||||
A1Out.create( features.size() + prior->getPadding(), basisSize.area(), CV_32F ); |
||||
A2Out.create( features.size() + prior->getPadding(), basisSize.area(), CV_32F ); |
||||
b1Out.create( features.size() + prior->getPadding(), 1, CV_32F ); |
||||
b2Out.create( features.size() + prior->getPadding(), 1, CV_32F ); |
||||
|
||||
if ( useOpenCL ) |
||||
{ |
||||
UMat A = A1Out.getUMat(); |
||||
Mat b1 = b1Out.getMat(); |
||||
Mat b2 = b2Out.getMat(); |
||||
|
||||
ocl::Kernel kernel( "fillDCTSampledPoints", _ocl_fillDCTSampledPointsSource ); |
||||
size_t globSize[] = {features.size(), basisSize.width, basisSize.height}; |
||||
kernel |
||||
.args( cv::ocl::KernelArg::ReadOnlyNoSize( Mat( features ).getUMat( ACCESS_READ ) ), |
||||
cv::ocl::KernelArg::WriteOnlyNoSize( A ), (int)features.size(), (int)basisSize.width, |
||||
(int)basisSize.height, (int)size.width, (int)size.height ) |
||||
.run( 3, globSize, 0, true ); |
||||
|
||||
for ( size_t i = 0; i < features.size(); ++i ) |
||||
{ |
||||
const Point2f flow = predictedFeatures[i] - features[i]; |
||||
b1.at<float>( i ) = flow.x; |
||||
b2.at<float>( i ) = flow.y; |
||||
} |
||||
} |
||||
else |
||||
{ |
||||
Mat A1 = A1Out.getMat(); |
||||
Mat b1 = b1Out.getMat(); |
||||
Mat b2 = b2Out.getMat(); |
||||
|
||||
for ( size_t i = 0; i < features.size(); ++i ) |
||||
{ |
||||
_cpu_fillDCTSampledPoints( A1.ptr<float>( i ), features[i], basisSize, size ); |
||||
const Point2f flow = predictedFeatures[i] - features[i]; |
||||
b1.at<float>( i ) = flow.x; |
||||
b2.at<float>( i ) = flow.y; |
||||
} |
||||
} |
||||
|
||||
Mat A1 = A1Out.getMat(); |
||||
Mat A2 = A2Out.getMat(); |
||||
Mat b1 = b1Out.getMat(); |
||||
Mat b2 = b2Out.getMat(); |
||||
|
||||
memcpy( A2.ptr<float>(), A1.ptr<float>(), features.size() * basisSize.area() * sizeof( float ) ); |
||||
prior->fillConstraints( A1.ptr<float>( features.size(), 0 ), A2.ptr<float>( features.size(), 0 ), |
||||
b1.ptr<float>( features.size(), 0 ), b2.ptr<float>( features.size(), 0 ) ); |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::calc( InputArray I0, InputArray I1, InputOutputArray flowOut ) |
||||
{ |
||||
const Size size = I0.size(); |
||||
CV_Assert( size == I1.size() ); |
||||
|
||||
UMat from, to; |
||||
if ( I0.channels() == 3 ) |
||||
{ |
||||
cvtColor( I0, from, COLOR_BGR2GRAY ); |
||||
from.convertTo( from, CV_8U ); |
||||
} |
||||
else |
||||
{ |
||||
I0.getMat().convertTo( from, CV_8U ); |
||||
} |
||||
if ( I1.channels() == 3 ) |
||||
{ |
||||
cvtColor( I1, to, COLOR_BGR2GRAY ); |
||||
to.convertTo( to, CV_8U ); |
||||
} |
||||
else |
||||
{ |
||||
I1.getMat().convertTo( to, CV_8U ); |
||||
} |
||||
|
||||
CV_Assert( from.channels() == 1 ); |
||||
CV_Assert( to.channels() == 1 ); |
||||
|
||||
const Mat fromOrig = from.getMat( ACCESS_READ ).clone(); |
||||
useOpenCL = flowOut.isUMat() && ocl::useOpenCL(); |
||||
|
||||
applyCLAHE( from, claheClip ); |
||||
applyCLAHE( to, claheClip ); |
||||
|
||||
std::vector<Point2f> features, predictedFeatures; |
||||
findSparseFeatures( from, to, features, predictedFeatures ); |
||||
removeOcclusions( from, to, features, predictedFeatures ); |
||||
|
||||
flowOut.create( size, CV_32FC2 ); |
||||
Mat flow = flowOut.getMat(); |
||||
|
||||
Mat w1, w2; |
||||
if ( prior.get() ) |
||||
{ |
||||
Mat A1, A2, b1, b2; |
||||
getSystem( A1, A2, b1, b2, features, predictedFeatures, size ); |
||||
solveLSQR( A1, b1, w1, dampingFactor * size.area() ); |
||||
solveLSQR( A2, b2, w2, dampingFactor * size.area() ); |
||||
} |
||||
else |
||||
{ |
||||
Mat A, b1, b2; |
||||
getSystem( A, b1, b2, features, predictedFeatures, size ); |
||||
solveLSQR( A, b1, w1, dampingFactor * size.area() ); |
||||
solveLSQR( A, b2, w2, dampingFactor * size.area() ); |
||||
} |
||||
Mat flowSmall( ( size / 8 ) * 2, CV_32FC2 ); |
||||
reduceToFlow( w1, w2, flowSmall, basisSize ); |
||||
resize( flowSmall, flow, size, 0, 0, INTER_LINEAR ); |
||||
ximgproc::fastGlobalSmootherFilter( fromOrig, flow, flow, 500, 2 ); |
||||
} |
||||
|
||||
OpticalFlowPCAFlow::OpticalFlowPCAFlow( Ptr<const PCAPrior> _prior, const Size _basisSize, float _sparseRate, |
||||
float _retainedCornersFraction, float _occlusionsThreshold, |
||||
float _dampingFactor, float _claheClip ) |
||||
: prior( _prior ), basisSize( _basisSize ), sparseRate( _sparseRate ), |
||||
retainedCornersFraction( _retainedCornersFraction ), occlusionsThreshold( _occlusionsThreshold ), |
||||
dampingFactor( _dampingFactor ), claheClip( _claheClip ), useOpenCL( false ) |
||||
{ |
||||
CV_Assert( sparseRate > 0 && sparseRate <= 0.1 ); |
||||
CV_Assert( retainedCornersFraction >= 0 && retainedCornersFraction <= 1.0 ); |
||||
CV_Assert( occlusionsThreshold > 0 ); |
||||
} |
||||
|
||||
void OpticalFlowPCAFlow::collectGarbage() {} |
||||
|
||||
Ptr<DenseOpticalFlow> createOptFlow_PCAFlow() { return makePtr<OpticalFlowPCAFlow>(); } |
||||
|
||||
PCAPrior::PCAPrior( const char *pathToPrior ) |
||||
{ |
||||
FILE *f = fopen( pathToPrior, "rb" ); |
||||
CV_Assert( f ); |
||||
|
||||
unsigned n = 0, m = 0; |
||||
CV_Assert( fread( &n, sizeof( n ), 1, f ) == 1 ); |
||||
CV_Assert( fread( &m, sizeof( m ), 1, f ) == 1 ); |
||||
|
||||
L1.create( n, m, CV_32F ); |
||||
L2.create( n, m, CV_32F ); |
||||
c1.create( n, 1, CV_32F ); |
||||
c2.create( n, 1, CV_32F ); |
||||
|
||||
CV_Assert( fread( L1.ptr<float>(), n * m * sizeof( float ), 1, f ) == 1 ); |
||||
CV_Assert( fread( L2.ptr<float>(), n * m * sizeof( float ), 1, f ) == 1 ); |
||||
CV_Assert( fread( c1.ptr<float>(), n * sizeof( float ), 1, f ) == 1 ); |
||||
CV_Assert( fread( c2.ptr<float>(), n * sizeof( float ), 1, f ) == 1 ); |
||||
|
||||
fclose( f ); |
||||
} |
||||
|
||||
void PCAPrior::fillConstraints( float *A1, float *A2, float *b1, float *b2 ) const |
||||
{ |
||||
memcpy( A1, L1.ptr<float>(), L1.size().area() * sizeof( float ) ); |
||||
memcpy( A2, L2.ptr<float>(), L2.size().area() * sizeof( float ) ); |
||||
memcpy( b1, c1.ptr<float>(), c1.size().area() * sizeof( float ) ); |
||||
memcpy( b2, c2.ptr<float>(), c2.size().area() * sizeof( float ) ); |
||||
} |
||||
} |
||||
} |
@ -0,0 +1,333 @@ |
||||
/*M///////////////////////////////////////////////////////////////////////////////////////
|
||||
//
|
||||
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
|
||||
//
|
||||
// By downloading, copying, installing or using the software you agree to this license.
|
||||
// If you do not agree to this license, do not download, install,
|
||||
// copy or use the software.
|
||||
//
|
||||
//
|
||||
// License Agreement
|
||||
// For Open Source Computer Vision Library
|
||||
//
|
||||
// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
|
||||
// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
|
||||
// Third party copyrights are property of their respective owners.
|
||||
//
|
||||
// Redistribution and use in source and binary forms, with or without modification,
|
||||
// are permitted provided that the following conditions are met:
|
||||
//
|
||||
// * Redistribution's of source code must retain the above copyright notice,
|
||||
// this list of conditions and the following disclaimer.
|
||||
//
|
||||
// * Redistribution's in binary form must reproduce the above copyright notice,
|
||||
// this list of conditions and the following disclaimer in the documentation
|
||||
// and/or other materials provided with the distribution.
|
||||
//
|
||||
// * The name of the copyright holders may not be used to endorse or promote products
|
||||
// derived from this software without specific prior written permission.
|
||||
//
|
||||
// This software is provided by the copyright holders and contributors "as is" and
|
||||
// any express or implied warranties, including, but not limited to, the implied
|
||||
// warranties of merchantability and fitness for a particular purpose are disclaimed.
|
||||
// In no event shall the Intel Corporation or contributors be liable for any direct,
|
||||
// indirect, incidental, special, exemplary, or consequential damages
|
||||
// (including, but not limited to, procurement of substitute goods or services;
|
||||
// loss of use, data, or profits; or business interruption) however caused
|
||||
// and on any theory of liability, whether in contract, strict liability,
|
||||
// or tort (including negligence or otherwise) arising in any way out of
|
||||
// the use of this software, even if advised of the possibility of such damage.
|
||||
//
|
||||
//M*/
|
||||
|
||||
#include "opencv2/core/core_c.h" |
||||
#include "opencv2/highgui.hpp" |
||||
#include "precomp.hpp" |
||||
|
||||
namespace cv |
||||
{ |
||||
namespace optflow |
||||
{ |
||||
namespace |
||||
{ |
||||
|
||||
const int patchRadius = 10; |
||||
const double thresholdMagnitudeFrac = 0.6666666666; |
||||
const int globalIters = 3; |
||||
const int localIters = 500; |
||||
const int minNumberOfSamples = 2; |
||||
//const bool debugOutput = true;
|
||||
|
||||
struct Magnitude |
||||
{ |
||||
float val; |
||||
int i; |
||||
int j; |
||||
|
||||
Magnitude( float _val, int _i, int _j ) : val( _val ), i( _i ), j( _j ) {} |
||||
Magnitude() {} |
||||
|
||||
bool operator<( const Magnitude &m ) const { return val > m.val; } |
||||
}; |
||||
|
||||
struct PartitionPredicate1 |
||||
{ |
||||
Vec< double, GPCPatchDescriptor::nFeatures > coef; |
||||
double rhs; |
||||
|
||||
PartitionPredicate1( const Vec< double, GPCPatchDescriptor::nFeatures > &_coef, double _rhs ) : coef( _coef ), rhs( _rhs ) {} |
||||
|
||||
bool operator()( const GPCPatchSample &sample ) const |
||||
{ |
||||
const bool direction1 = ( coef.dot( sample.first.feature ) < rhs ); |
||||
const bool direction2 = ( coef.dot( sample.second.feature ) < rhs ); |
||||
return direction1 == false && direction1 == direction2; |
||||
} |
||||
}; |
||||
|
||||
struct PartitionPredicate2 |
||||
{ |
||||
Vec< double, GPCPatchDescriptor::nFeatures > coef; |
||||
double rhs; |
||||
|
||||
PartitionPredicate2( const Vec< double, GPCPatchDescriptor::nFeatures > &_coef, double _rhs ) : coef( _coef ), rhs( _rhs ) {} |
||||
|
||||
bool operator()( const GPCPatchSample &sample ) const |
||||
{ |
||||
const bool direction1 = ( coef.dot( sample.first.feature ) < rhs ); |
||||
const bool direction2 = ( coef.dot( sample.second.feature ) < rhs ); |
||||
return direction1 != direction2; |
||||
} |
||||
}; |
||||
|
||||
float normL2Sqr( const Vec2f &v ) { return v[0] * v[0] + v[1] * v[1]; } |
||||
|
||||
bool checkBounds( int i, int j, Size sz ) |
||||
{ |
||||
return i >= patchRadius && j >= patchRadius && i + patchRadius < sz.height && j + patchRadius < sz.width; |
||||
} |
||||
|
||||
void getTrainingSamples( const Mat &from, const Mat &to, const Mat >, GPCSamplesVector &samples ) |
||||
{ |
||||
const Size sz = gt.size(); |
||||
std::vector< Magnitude > mag; |
||||
|
||||
for ( int i = patchRadius; i + patchRadius < sz.height; ++i ) |
||||
for ( int j = patchRadius; j + patchRadius < sz.width; ++j ) |
||||
mag.push_back( Magnitude( normL2Sqr( gt.at< Vec2f >( i, j ) ), i, j ) ); |
||||
|
||||
size_t n = size_t(mag.size() * thresholdMagnitudeFrac); // As suggested in the paper, we discard part of the training samples
|
||||
// with a small displacement and train to better distinguish hard pairs.
|
||||
std::nth_element( mag.begin(), mag.begin() + n, mag.end() ); |
||||
mag.resize( n ); |
||||
std::random_shuffle( mag.begin(), mag.end() ); |
||||
n /= patchRadius; |
||||
mag.resize( n ); |
||||
|
||||
Mat fromCh[3], toCh[3]; |
||||
split( from, fromCh ); |
||||
split( to, toCh ); |
||||
|
||||
for ( size_t k = 0; k < n; ++k ) |
||||
{ |
||||
int i0 = mag[k].i; |
||||
int j0 = mag[k].j; |
||||
int i1 = i0 + cvRound( gt.at< Vec2f >( i0, j0 )[1] ); |
||||
int j1 = j0 + cvRound( gt.at< Vec2f >( i0, j0 )[0] ); |
||||
if ( checkBounds( i1, j1, sz ) ) |
||||
samples.push_back( std::make_pair( GPCPatchDescriptor( fromCh, i0, j0 ), GPCPatchDescriptor( toCh, i1, j1 ) ) ); |
||||
} |
||||
} |
||||
|
||||
/* Sample random number from Cauchy distribution. */ |
||||
double getRandomCauchyScalar() |
||||
{ |
||||
static RNG rng; |
||||
return tan( rng.uniform( -1.54, 1.54 ) ); // I intentionally used the value slightly less than PI/2 to enforce strictly
|
||||
// zero probability for large numbers. Resulting PDF for Cauchy has
|
||||
// truncated "tails".
|
||||
} |
||||
|
||||
/* Sample random vector from Cauchy distribution (pointwise, i.e. vector whose components are independent random
|
||||
* variables from Cauchy distribution) */ |
||||
void getRandomCauchyVector( Vec< double, GPCPatchDescriptor::nFeatures > &v ) |
||||
{ |
||||
for ( unsigned i = 0; i < GPCPatchDescriptor::nFeatures; ++i ) |
||||
v[i] = getRandomCauchyScalar(); |
||||
} |
||||
} |
||||
|
||||
GPCPatchDescriptor::GPCPatchDescriptor( const Mat *imgCh, int i, int j ) |
||||
{ |
||||
Rect roi( j - patchRadius, i - patchRadius, 2 * patchRadius, 2 * patchRadius ); |
||||
Mat freqDomain; |
||||
dct( imgCh[0]( roi ), freqDomain ); |
||||
|
||||
feature[0] = freqDomain.at< float >( 0, 0 ); |
||||
feature[1] = freqDomain.at< float >( 0, 1 ); |
||||
feature[2] = freqDomain.at< float >( 0, 2 ); |
||||
feature[3] = freqDomain.at< float >( 0, 3 ); |
||||
|
||||
feature[4] = freqDomain.at< float >( 1, 0 ); |
||||
feature[5] = freqDomain.at< float >( 1, 1 ); |
||||
feature[6] = freqDomain.at< float >( 1, 2 ); |
||||
feature[7] = freqDomain.at< float >( 1, 3 ); |
||||
|
||||
feature[8] = freqDomain.at< float >( 2, 0 ); |
||||
feature[9] = freqDomain.at< float >( 2, 1 ); |
||||
feature[10] = freqDomain.at< float >( 2, 2 ); |
||||
feature[11] = freqDomain.at< float >( 2, 3 ); |
||||
|
||||
feature[12] = freqDomain.at< float >( 3, 0 ); |
||||
feature[13] = freqDomain.at< float >( 3, 1 ); |
||||
feature[14] = freqDomain.at< float >( 3, 2 ); |
||||
feature[15] = freqDomain.at< float >( 3, 3 ); |
||||
|
||||
feature[16] = cv::sum( imgCh[1]( roi ) )[0] / ( 2 * patchRadius ); |
||||
feature[17] = cv::sum( imgCh[2]( roi ) )[0] / ( 2 * patchRadius ); |
||||
} |
||||
|
||||
bool GPCTree::trainNode( size_t nodeId, SIter begin, SIter end, unsigned depth ) |
||||
{ |
||||
if ( std::distance( begin, end ) < minNumberOfSamples ) |
||||
return false; |
||||
|
||||
if ( nodeId >= nodes.size() ) |
||||
nodes.resize( nodeId + 1 ); |
||||
|
||||
Node &node = nodes[nodeId]; |
||||
|
||||
// Select the best hyperplane
|
||||
unsigned globalBestScore = 0; |
||||
std::vector< double > values; |
||||
|
||||
for ( int j = 0; j < globalIters; ++j ) |
||||
{ // Global search step
|
||||
Vec< double, GPCPatchDescriptor::nFeatures > coef; |
||||
unsigned localBestScore = 0; |
||||
getRandomCauchyVector( coef ); |
||||
|
||||
for ( int i = 0; i < localIters; ++i ) |
||||
{ // Local search step
|
||||
double randomModification = getRandomCauchyScalar(); |
||||
const int pos = i % GPCPatchDescriptor::nFeatures; |
||||
std::swap( coef[pos], randomModification ); |
||||
values.clear(); |
||||
|
||||
for ( SIter iter = begin; iter != end; ++iter ) |
||||
{ |
||||
values.push_back( coef.dot( iter->first.feature ) ); |
||||
values.push_back( coef.dot( iter->second.feature ) ); |
||||
} |
||||
|
||||
std::nth_element( values.begin(), values.begin() + values.size() / 2, values.end() ); |
||||
const double median = values[values.size() / 2]; |
||||
unsigned correct = 0; |
||||
|
||||
for ( SIter iter = begin; iter != end; ++iter ) |
||||
{ |
||||
const bool direction = ( coef.dot( iter->first.feature ) < median ); |
||||
if ( direction == ( coef.dot( iter->second.feature ) < median ) ) |
||||
++correct; |
||||
} |
||||
|
||||
if ( correct > localBestScore ) |
||||
localBestScore = correct; |
||||
else |
||||
coef[pos] = randomModification; |
||||
|
||||
if ( correct > globalBestScore ) |
||||
{ |
||||
globalBestScore = correct; |
||||
node.coef = coef; |
||||
node.rhs = median; |
||||
|
||||
/*if ( debugOutput )
|
||||
{ |
||||
printf( "[%u] Updating weights: correct %.2f (%u/%ld)\n", depth, double( correct ) / std::distance( begin, end ), correct, |
||||
std::distance( begin, end ) ); |
||||
for ( unsigned k = 0; k < GPCPatchDescriptor::nFeatures; ++k ) |
||||
printf( "%.3f ", coef[k] ); |
||||
printf( "\n" ); |
||||
}*/ |
||||
} |
||||
} |
||||
} |
||||
// Partition vector with samples according to the hyperplane in QuickSort-like manner.
|
||||
// Unlike QuickSort, we need to partition it into 3 parts (left subtree samples; undefined samples; right subtree
|
||||
// samples), so we call it two times.
|
||||
SIter leftEnd = std::partition( begin, end, PartitionPredicate1( node.coef, node.rhs ) ); // Separate left subtree samples from others.
|
||||
SIter rightBegin = |
||||
std::partition( leftEnd, end, PartitionPredicate2( node.coef, node.rhs ) ); // Separate undefined samples from right subtree samples.
|
||||
|
||||
node.left = ( trainNode( nodeId * 2 + 1, begin, leftEnd, depth + 1 ) ) ? unsigned(nodeId * 2 + 1) : 0; |
||||
node.right = ( trainNode( nodeId * 2 + 2, rightBegin, end, depth + 1 ) ) ? unsigned(nodeId * 2 + 2) : 0; |
||||
|
||||
return true; |
||||
} |
||||
|
||||
void GPCTree::train( GPCSamplesVector &samples ) |
||||
{ |
||||
nodes.reserve( samples.size() * 2 - 1 ); // set upper bound for the possible number of nodes so all subsequent resize() will be no-op
|
||||
trainNode( 0, samples.begin(), samples.end(), 0 ); |
||||
} |
||||
|
||||
void GPCTree::write( FileStorage &fs ) const |
||||
{ |
||||
if ( nodes.empty() ) |
||||
CV_Error( CV_StsBadArg, "Tree have not been trained" ); |
||||
fs << "nodes" << nodes; |
||||
} |
||||
|
||||
void GPCTree::read( const FileNode &fn ) { fn["nodes"] >> nodes; } |
||||
|
||||
Ptr< GPCTrainingSamples > GPCTrainingSamples::create( const std::vector< String > &imagesFrom, const std::vector< String > &imagesTo, |
||||
const std::vector< String > > ) |
||||
{ |
||||
CV_Assert( imagesFrom.size() == imagesTo.size() ); |
||||
CV_Assert( imagesFrom.size() == gt.size() ); |
||||
|
||||
Ptr< GPCTrainingSamples > ts = makePtr< GPCTrainingSamples >(); |
||||
for ( size_t i = 0; i < imagesFrom.size(); ++i ) |
||||
{ |
||||
Mat from = imread( imagesFrom[i] ); |
||||
Mat to = imread( imagesTo[i] ); |
||||
Mat gtFlow = readOpticalFlow( gt[i] ); |
||||
|
||||
CV_Assert( from.size == to.size ); |
||||
CV_Assert( from.size == gtFlow.size ); |
||||
CV_Assert( from.channels() == 3 ); |
||||
CV_Assert( to.channels() == 3 ); |
||||
|
||||
from.convertTo( from, CV_32FC3 ); |
||||
to.convertTo( to, CV_32FC3 ); |
||||
cvtColor( from, from, COLOR_BGR2YCrCb ); |
||||
cvtColor( to, to, COLOR_BGR2YCrCb ); |
||||
|
||||
getTrainingSamples( from, to, gtFlow, ts->samples ); |
||||
} |
||||
|
||||
return ts; |
||||
} |
||||
|
||||
} // namespace optflow
|
||||
|
||||
void write( FileStorage &fs, const String &name, const optflow::GPCTree::Node &node ) |
||||
{ |
||||
cv::internal::WriteStructContext ws( fs, name, CV_NODE_SEQ + CV_NODE_FLOW ); |
||||
for ( unsigned i = 0; i < optflow::GPCPatchDescriptor::nFeatures; ++i ) |
||||
write( fs, node.coef[i] ); |
||||
write( fs, node.rhs ); |
||||
write( fs, (int)node.left ); |
||||
write( fs, (int)node.right ); |
||||
} |
||||
|
||||
void read( const FileNode &fn, optflow::GPCTree::Node &node, optflow::GPCTree::Node ) |
||||
{ |
||||
FileNodeIterator it = fn.begin(); |
||||
for ( unsigned i = 0; i < optflow::GPCPatchDescriptor::nFeatures; ++i ) |
||||
it >> node.coef[i]; |
||||
it >> node.rhs >> (int &)node.left >> (int &)node.right; |
||||
} |
||||
|
||||
} // namespace cv
|
Loading…
Reference in new issue