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/*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 "precomp.hpp"
using namespace cv;
using namespace cv::cuda;
#if !defined HAVE_CUDA || defined(CUDA_DISABLER)
Ptr<cuda::BackgroundSubtractorMOG2> cv::cuda::createBackgroundSubtractorMOG2(int, double, bool) { throw_no_cuda(); return Ptr<cuda::BackgroundSubtractorMOG2>(); }
#else
namespace cv { namespace cuda { namespace device
{
namespace mog2
{
void loadConstants(int nmixtures, float Tb, float TB, float Tg, float varInit, float varMin, float varMax, float tau, unsigned char shadowVal);
void mog2_gpu(PtrStepSzb frame, int cn, PtrStepSzb fgmask, PtrStepSzb modesUsed, PtrStepSzf weight, PtrStepSzf variance, PtrStepSzb mean, float alphaT, float prune, bool detectShadows, cudaStream_t stream);
void getBackgroundImage2_gpu(int cn, PtrStepSzb modesUsed, PtrStepSzf weight, PtrStepSzb mean, PtrStepSzb dst, cudaStream_t stream);
}
}}}
namespace
{
// default parameters of gaussian background detection algorithm
const int defaultHistory = 500; // Learning rate; alpha = 1/defaultHistory2
const float defaultVarThreshold = 4.0f * 4.0f;
const int defaultNMixtures = 5; // maximal number of Gaussians in mixture
const float defaultBackgroundRatio = 0.9f; // threshold sum of weights for background test
const float defaultVarThresholdGen = 3.0f * 3.0f;
const float defaultVarInit = 15.0f; // initial variance for new components
const float defaultVarMax = 5.0f * defaultVarInit;
const float defaultVarMin = 4.0f;
// additional parameters
const float defaultCT = 0.05f; // complexity reduction prior constant 0 - no reduction of number of components
const unsigned char defaultShadowValue = 127; // value to use in the segmentation mask for shadows, set 0 not to do shadow detection
const float defaultShadowThreshold = 0.5f; // Tau - shadow threshold, see the paper for explanation
class MOG2Impl : public cuda::BackgroundSubtractorMOG2
{
public:
MOG2Impl(int history, double varThreshold, bool detectShadows);
void apply(InputArray image, OutputArray fgmask, double learningRate=-1);
void apply(InputArray image, OutputArray fgmask, double learningRate, Stream& stream);
void getBackgroundImage(OutputArray backgroundImage) const;
void getBackgroundImage(OutputArray backgroundImage, Stream& stream) const;
int getHistory() const { return history_; }
void setHistory(int history) { history_ = history; }
int getNMixtures() const { return nmixtures_; }
void setNMixtures(int nmixtures) { nmixtures_ = nmixtures; }
double getBackgroundRatio() const { return backgroundRatio_; }
void setBackgroundRatio(double ratio) { backgroundRatio_ = (float) ratio; }
double getVarThreshold() const { return varThreshold_; }
void setVarThreshold(double varThreshold) { varThreshold_ = (float) varThreshold; }
double getVarThresholdGen() const { return varThresholdGen_; }
void setVarThresholdGen(double varThresholdGen) { varThresholdGen_ = (float) varThresholdGen; }
double getVarInit() const { return varInit_; }
void setVarInit(double varInit) { varInit_ = (float) varInit; }
double getVarMin() const { return varMin_; }
void setVarMin(double varMin) { varMin_ = (float) varMin; }
double getVarMax() const { return varMax_; }
void setVarMax(double varMax) { varMax_ = (float) varMax; }
double getComplexityReductionThreshold() const { return ct_; }
void setComplexityReductionThreshold(double ct) { ct_ = (float) ct; }
bool getDetectShadows() const { return detectShadows_; }
void setDetectShadows(bool detectShadows) { detectShadows_ = detectShadows; }
int getShadowValue() const { return shadowValue_; }
void setShadowValue(int value) { shadowValue_ = (uchar) value; }
double getShadowThreshold() const { return shadowThreshold_; }
void setShadowThreshold(double threshold) { shadowThreshold_ = (float) threshold; }
private:
void initialize(Size frameSize, int frameType);
int history_;
int nmixtures_;
float backgroundRatio_;
float varThreshold_;
float varThresholdGen_;
float varInit_;
float varMin_;
float varMax_;
float ct_;
bool detectShadows_;
uchar shadowValue_;
float shadowThreshold_;
Size frameSize_;
int frameType_;
int nframes_;
GpuMat weight_;
GpuMat variance_;
GpuMat mean_;
//keep track of number of modes per pixel
GpuMat bgmodelUsedModes_;
};
MOG2Impl::MOG2Impl(int history, double varThreshold, bool detectShadows) :
frameSize_(0, 0), frameType_(0), nframes_(0)
{
history_ = history > 0 ? history : defaultHistory;
varThreshold_ = varThreshold > 0 ? (float) varThreshold : defaultVarThreshold;
detectShadows_ = detectShadows;
nmixtures_ = defaultNMixtures;
backgroundRatio_ = defaultBackgroundRatio;
varInit_ = defaultVarInit;
varMax_ = defaultVarMax;
varMin_ = defaultVarMin;
varThresholdGen_ = defaultVarThresholdGen;
ct_ = defaultCT;
shadowValue_ = defaultShadowValue;
shadowThreshold_ = defaultShadowThreshold;
}
void MOG2Impl::apply(InputArray image, OutputArray fgmask, double learningRate)
{
apply(image, fgmask, learningRate, Stream::Null());
}
void MOG2Impl::apply(InputArray _frame, OutputArray _fgmask, double learningRate, Stream& stream)
{
using namespace cv::cuda::device::mog2;
GpuMat frame = _frame.getGpuMat();
int ch = frame.channels();
int work_ch = ch;
if (nframes_ == 0 || learningRate >= 1.0 || frame.size() != frameSize_ || work_ch != mean_.channels())
initialize(frame.size(), frame.type());
_fgmask.create(frameSize_, CV_8UC1);
GpuMat fgmask = _fgmask.getGpuMat();
fgmask.setTo(Scalar::all(0), stream);
++nframes_;
learningRate = learningRate >= 0 && nframes_ > 1 ? learningRate : 1.0 / std::min(2 * nframes_, history_);
CV_Assert( learningRate >= 0 );
mog2_gpu(frame, frame.channels(), fgmask, bgmodelUsedModes_, weight_, variance_, mean_,
(float) learningRate, static_cast<float>(-learningRate * ct_), detectShadows_, StreamAccessor::getStream(stream));
}
void MOG2Impl::getBackgroundImage(OutputArray backgroundImage) const
{
getBackgroundImage(backgroundImage, Stream::Null());
}
void MOG2Impl::getBackgroundImage(OutputArray _backgroundImage, Stream& stream) const
{
using namespace cv::cuda::device::mog2;
_backgroundImage.create(frameSize_, frameType_);
GpuMat backgroundImage = _backgroundImage.getGpuMat();
getBackgroundImage2_gpu(backgroundImage.channels(), bgmodelUsedModes_, weight_, mean_, backgroundImage, StreamAccessor::getStream(stream));
}
void MOG2Impl::initialize(cv::Size frameSize, int frameType)
{
using namespace cv::cuda::device::mog2;
CV_Assert( frameType == CV_8UC1 || frameType == CV_8UC3 || frameType == CV_8UC4 );
frameSize_ = frameSize;
frameType_ = frameType;
nframes_ = 0;
int ch = CV_MAT_CN(frameType);
int work_ch = ch;
// for each gaussian mixture of each pixel bg model we store ...
// the mixture weight (w),
// the mean (nchannels values) and
// the covariance
weight_.create(frameSize.height * nmixtures_, frameSize_.width, CV_32FC1);
variance_.create(frameSize.height * nmixtures_, frameSize_.width, CV_32FC1);
mean_.create(frameSize.height * nmixtures_, frameSize_.width, CV_32FC(work_ch));
//make the array for keeping track of the used modes per pixel - all zeros at start
bgmodelUsedModes_.create(frameSize_, CV_8UC1);
bgmodelUsedModes_.setTo(Scalar::all(0));
loadConstants(nmixtures_, varThreshold_, backgroundRatio_, varThresholdGen_, varInit_, varMin_, varMax_, shadowThreshold_, shadowValue_);
}
}
Ptr<cuda::BackgroundSubtractorMOG2> cv::cuda::createBackgroundSubtractorMOG2(int history, double varThreshold, bool detectShadows)
{
return makePtr<MOG2Impl>(history, varThreshold, detectShadows);
}
#endif