bg_sub.cpp

//opencv
#include "opencv2/imgcodecs.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/videoio.hpp"
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/video/video.hpp>
#include <opencv2/core/types_c.h>

//C
#include <stdio.h>
//C++
#include <iostream>
#include <sstream>

using namespace cv;
using namespace std;

// Global variables
Mat frame; //current frame
Mat fgMaskMOG2; //fg mask fg mask generated by MOG2 method
Ptr<BackgroundSubtractorMOG2> pMOG2; //MOG2 Background subtractor
int keyboard; //input from keyboard


/** Function Headers */
void help();
void processVideo(char* videoFilename);


void help()
{
    cout
    << "--------------------------------------------------------------------------" << endl
    << "Usage:"                                                                     << endl
    << "BGSubtract.exe -vid <video filename>"                                       << endl
    << "--------------------------------------------------------------------------" << endl
    << endl;
}

void morph(Mat &frame){
	Mat erodeMat = getStructuringElement(MORPH_ELLIPSE, Size(4, 4));
	Mat dilateMat = getStructuringElement(MORPH_ELLIPSE, Size(8, 8));

	erode(frame, frame, erodeMat);
	erode(frame, frame, erodeMat);
	dilate(frame, frame, dilateMat);
	dilate(frame, frame, dilateMat);
}

void MyCallbackForShadowValue(int iValueForShadowValue, void*)
{
	pMOG2->setShadowValue(iValueForShadowValue);
}

void MyCallbackForNMixtures(int iValueForNMixtures, void*)
{
	pMOG2->setNMixtures(iValueForNMixtures);
}

void MyCallbackForHistory(int iValueForHistory, void*)
{
	pMOG2->setHistory(iValueForHistory);
}

void MyCallbackForShadowThreshold(int iValueForShadowThreshold, void*)
{
	double iShadowThreshold = (iValueForShadowThreshold / (double)100);
	pMOG2->setShadowThreshold(iShadowThreshold);
}

void MyCallbackForVarThreshold(int iValueForVarThreshold, void*)
{
	pMOG2->setVarThreshold(iValueForVarThreshold);
}

void MyCallbackForBackgroundRatio(int iValueForBackgroundRatio, void*)
{
	double iBackgroundRatio = (iValueForBackgroundRatio / (double)100);
	pMOG2->setBackgroundRatio(iBackgroundRatio);
}

void MyCallbackForVarThresholdGen(int iValueForVarThresholdGen, void*)
{
	pMOG2->setVarThresholdGen(iValueForVarThresholdGen);
}

void MyCallbackForBlur(int iValueForBlur, void *userdata)
{
	if (iValueForBlur <= 0) {
		return;
	}
	Mat img = *((Mat*)userdata);
	blur(img, img, Size(iValueForBlur, iValueForBlur)); // Blur the image
	imshow("Frame", img);
}

/**
 * @function processVideo
 */
void processVideo(char* videoFilename) {
    //create the capture object
    VideoCapture capture(videoFilename);
    if(!capture.isOpened()){
        //error in opening the video input
        cerr << "Unable to open video file: " << videoFilename << endl;
        exit(EXIT_FAILURE);
    }

	// Default params for trackbar (Same as initial params setup in Main)
	int iValueForShadowValue = 0;
	int iValueForNMixtures = 3;
	int iValueForHistory = 200;
	int iValueForShadowThreshold = 10;
	int iValueForVarThreshold = 400;
	int iValueForBackgroundRatio = 60;
	int iValueForVarThresholdGen = 2;

	int iValueForBlur = 5;


    //read input data. ESC or 'q' for quitting
    while( (char)keyboard != 'q' && (char)keyboard != 27 ){
        //read the current frame
        if(!capture.read(frame)) {
            cerr << "Unable to read next frame." << endl;
            cerr << "Exiting..." << endl;
            exit(EXIT_FAILURE);
        }

		
		//cvtColor(frame, frame, CV_BGR2GRAY);// Convert the image to grayscale
		createTrackbar("Blur", "Frame", &iValueForBlur, 20, MyCallbackForBlur, (void*)(&frame));
		MyCallbackForBlur(iValueForBlur, &frame);

		pMOG2->apply(frame, fgMaskMOG2, -.1); // (original, new mat, learing rate)

		//Create trackbars to change backgroundsubtractorMOG2 parameters
		createTrackbar("ShadowValue", "FG Mask MOG 2", &iValueForShadowValue, 254, MyCallbackForShadowValue);
		createTrackbar("NMixtures", "FG Mask MOG 2", &iValueForNMixtures, 7, MyCallbackForNMixtures);
		createTrackbar("History", "FG Mask MOG 2", &iValueForHistory, 500, MyCallbackForHistory);
		createTrackbar("ShadowThreshold", "FG Mask MOG 2", &iValueForShadowThreshold, 100, MyCallbackForShadowThreshold);
		createTrackbar("VarThreshold", "FG Mask MOG 2", &iValueForVarThreshold, 500, MyCallbackForVarThreshold);
		createTrackbar("BGRatio", "FG Mask MOG 2", &iValueForBackgroundRatio, 100, MyCallbackForBackgroundRatio);
		createTrackbar("ThresholdGen", "FG Mask MOG 2", &iValueForVarThresholdGen, 5, MyCallbackForVarThresholdGen);
		imshow("FG Mask MOG 2", fgMaskMOG2);

		//medianBlur(fgMaskMOG2, fgMaskMOG2,9); // Too slow

		morph(fgMaskMOG2);
		imshow("Morph", fgMaskMOG2);

        //get the input from the keyboard
        keyboard = waitKey( 30 );

    }
    //delete capture object
    capture.release();
}


/** Main */
int main(int argc, char* argv[])
{
	//print help information
	help();

	//check for the input parameter correctness
	if (argc != 3) {
		cerr << "Incorret input list" << endl;
		cerr << "exiting..." << endl;
		return EXIT_FAILURE;
	}

	//create GUI windows
	namedWindow("Frame");
	namedWindow("FG Mask MOG 2", 1);
	namedWindow("Morph");


	//create Background Subtractor objects
	pMOG2 = createBackgroundSubtractorMOG2(200, 16, true); //MOG2 approach
	pMOG2->setDetectShadows(true);
	pMOG2->setShadowValue(0); // Sets the showdow color (0-black, 255-white)
	pMOG2->setShadowThreshold(.5); //Originally ftau?
	pMOG2->setVarThreshold(400); //Double
	pMOG2->setNMixtures(3); // Int
	pMOG2->setBackgroundRatio(0.6); //Double
	pMOG2->setVarThresholdGen(2);

	if (strcmp(argv[1], "-vid") == 0) {
		//input data coming from a video
		processVideo(argv[2]);
	}
	else {
		//error in reading input parameters
		cerr << "Please, check the input parameters." << endl;
		cerr << "Exiting..." << endl;
		return EXIT_FAILURE;
	}
	//destroy GUI windows
	destroyAllWindows();
	return EXIT_SUCCESS;
}