Open Source Computer Vision Library https://opencv.org/
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Background Segmentation
=======================
.. highlight:: cpp
cuda::BackgroundSubtractorMOG
-----------------------------
Gaussian Mixture-based Background/Foreground Segmentation Algorithm.
.. ocv:class:: cuda::BackgroundSubtractorMOG : public cv::BackgroundSubtractorMOG
The class discriminates between foreground and background pixels by building and maintaining a model of the background. Any pixel which does not fit this model is then deemed to be foreground. The class implements algorithm described in [MOG2001]_.
.. seealso:: :ocv:class:`BackgroundSubtractorMOG`
.. note::
* An example on gaussian mixture based background/foreground segmantation can be found at opencv_source_code/samples/gpu/bgfg_segm.cpp
cuda::createBackgroundSubtractorMOG
-----------------------------------
Creates mixture-of-gaussian background subtractor
.. ocv:function:: Ptr<cuda::BackgroundSubtractorMOG> cuda::createBackgroundSubtractorMOG(int history=200, int nmixtures=5, double backgroundRatio=0.7, double noiseSigma=0)
:param history: Length of the history.
:param nmixtures: Number of Gaussian mixtures.
:param backgroundRatio: Background ratio.
:param noiseSigma: Noise strength (standard deviation of the brightness or each color channel). 0 means some automatic value.
cuda::BackgroundSubtractorMOG2
------------------------------
Gaussian Mixture-based Background/Foreground Segmentation Algorithm.
.. ocv:class:: cuda::BackgroundSubtractorMOG2 : public cv::BackgroundSubtractorMOG2
The class discriminates between foreground and background pixels by building and maintaining a model of the background. Any pixel which does not fit this model is then deemed to be foreground. The class implements algorithm described in [MOG2004]_.
.. seealso:: :ocv:class:`BackgroundSubtractorMOG2`
cuda::createBackgroundSubtractorMOG2
------------------------------------
Creates MOG2 Background Subtractor
.. ocv:function:: Ptr<cuda::BackgroundSubtractorMOG2> cuda::createBackgroundSubtractorMOG2( int history=500, double varThreshold=16, bool detectShadows=true )
:param history: Length of the history.
:param varThreshold: Threshold on the squared Mahalanobis distance between the pixel and the model to decide whether a pixel is well described by the background model. This parameter does not affect the background update.
:param detectShadows: If true, the algorithm will detect shadows and mark them. It decreases the speed a bit, so if you do not need this feature, set the parameter to false.
cuda::BackgroundSubtractorGMG
-----------------------------
Background/Foreground Segmentation Algorithm.
.. ocv:class:: cuda::BackgroundSubtractorGMG : public cv::BackgroundSubtractorGMG
The class discriminates between foreground and background pixels by building and maintaining a model of the background. Any pixel which does not fit this model is then deemed to be foreground. The class implements algorithm described in [GMG2012]_.
cuda::createBackgroundSubtractorGMG
-----------------------------------
Creates GMG Background Subtractor
.. ocv:function:: Ptr<cuda::BackgroundSubtractorGMG> cuda::createBackgroundSubtractorGMG(int initializationFrames = 120, double decisionThreshold = 0.8)
:param initializationFrames: Number of frames of video to use to initialize histograms.
:param decisionThreshold: Value above which pixel is determined to be FG.
cuda::BackgroundSubtractorFGD
-----------------------------
.. ocv:class:: cuda::BackgroundSubtractorFGD : public cv::BackgroundSubtractor
The class discriminates between foreground and background pixels by building and maintaining a model of the background. Any pixel which does not fit this model is then deemed to be foreground. The class implements algorithm described in [FGD2003]_. ::
class CV_EXPORTS BackgroundSubtractorFGD : public cv::BackgroundSubtractor
{
public:
virtual void getForegroundRegions(OutputArrayOfArrays foreground_regions) = 0;
};
.. seealso:: :ocv:class:`BackgroundSubtractor`
cuda::BackgroundSubtractorFGD::getForegroundRegions
---------------------------------------------------
Returns the output foreground regions calculated by :ocv:func:`findContours`.
.. ocv:function:: void cuda::BackgroundSubtractorFGD::getForegroundRegions(OutputArrayOfArrays foreground_regions)
:params foreground_regions: Output array (CPU memory).
cuda::createBackgroundSubtractorFGD
-----------------------------------
Creates FGD Background Subtractor
.. ocv:function:: Ptr<cuda::BackgroundSubtractorGMG> cuda::createBackgroundSubtractorFGD(const FGDParams& params = FGDParams())
:param params: Algorithm's parameters. See [FGD2003]_ for explanation.
.. [FGD2003] Liyuan Li, Weimin Huang, Irene Y.H. Gu, and Qi Tian. *Foreground Object Detection from Videos Containing Complex Background*. ACM MM2003 9p, 2003.
.. [MOG2001] P. KadewTraKuPong and R. Bowden. *An improved adaptive background mixture model for real-time tracking with shadow detection*. Proc. 2nd European Workshop on Advanced Video-Based Surveillance Systems, 2001
.. [MOG2004] Z. Zivkovic. *Improved adaptive Gausian mixture model for background subtraction*. International Conference Pattern Recognition, UK, August, 2004
.. [GMG2012] A. Godbehere, A. Matsukawa and K. Goldberg. *Visual Tracking of Human Visitors under Variable-Lighting Conditions for a Responsive Audio Art Installation*. American Control Conference, Montreal, June 2012