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### background detection tutorial: error using MOG pointers

Hi everyone, I was trying to go through this background detection tutorial:

http://docs.opencv.org/trunk/doc/tutorials/video/background_subtraction/background_subtraction.html#background-subtraction

The MOG pointer is initialized as

Ptr<BackgroundSubtractor> pMOG; //MOG Background subtractor


and in main, it is used in the following manner:

pMOG = createBackgroundSubtractorMOG();


However, this yields the following error:

Error: Identifier "createBackgroundSubtractorMOG" is undefined

Also, when the background model is to be updated, the following command is used:

pMOG->apply(frame, fgMaskMOG);


Which in turn yields the following error:

Error: class "cv::BackgroundSubtractor" has no member "apply"