OpenCV_基于自适应背景更新的运动目标检测

转自/article/2271962.html

下面这段代码利用OpenCV实现了最为简单的基于自适应背景更新的运动目标检测算法。

即：

运动前景提取——背景减除

foreground = |frame - background| > threshold

更新背景模型——滑动平均滤波

background = background + (frame - background) * alpha = background * (1 - alpha) + frame * alpha

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//运动前景检测——基于自适应背景更新

//Author: www.icvpr.com

//Blog: http://blog.csdn.net/icvpr
#include <iostream>

#include <string>

#include <opencv2/opencv.hpp>

int main(int argc, char** argv)

{

std::string videoFileName = "../test.avi";

int threshold = 25 ; // 二值化阈值

float alpha = 0.01; // 更新速度 [0, 1]

cv::VideoCapture capture;

capture.open(videoFileName);

if (!capture.isOpened())

{

std::cout<<"cannot open video"<<std::endl;

return -1;

}

cv::Mat foregroundImg;

cv::Mat foregroundMat;

cv::Mat backgroundImg;

cv::Mat backgroundMat;

cv::Mat frame;

cv::Mat grayImg;

cv::Mat grayMat;

while (capture.read(frame))

{

cv::cvtColor(frame, grayImg, CV_BGR2GRAY);

grayImg.convertTo(grayMat, CV_32FC1);

if (backgroundMat.empty())

{

grayImg.copyTo(backgroundImg);

grayImg.convertTo(backgroundMat, CV_32FC1);

}

// 背景减除

cv::absdiff(grayMat, backgroundMat, foregroundMat);

// 自适应背景更新

cv::addWeighted(backgroundMat, alpha, foregroundMat, 1-alpha, 0, backgroundMat);

// 二值化，获取前景像素点

cv::threshold(foregroundMat, foregroundMat, threshold, 255, CV_THRESH_BINARY);

// 为了显示用，将CV_32FC1转换为CV_8U

cv::convertScaleAbs(foregroundMat, foregroundImg);

cv::convertScaleAbs(backgroundMat, backgroundImg);

cv::imshow("frame", frame);

cv::imshow("foreground", foregroundImg);

cv::imshow("background", backgroundImg);

if (cv::waitKey(25) > 0)

{

break;

}

}

return 0;

}