OpenCV 基于色彩的对象检测与跟踪

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u012841922/article/details/86481988

视频来源：https://www.youtube.com/watch?v=EvIwL0aSCZY

以下代码用OpenCV实现了视频中基于色彩的对象检测与跟踪，该方法受光照变化影响较大。

//
//  main.cpp
//  opencv-learning
//
//  Created by _R on 2019/1/9.
//  Copyright © 2019 _R. All rights reserved.
//

#include <iostream>
#include <opencv2/opencv.hpp>

using namespace std;
using namespace cv;

Rect roi;

void printAllContours(Mat &object, Mat &frame);

void trackObject(Mat &frame, Rect &roi);

int main(int argc, char* argv[])
{
    VideoCapture video = VideoCapture("/Users/_R/Desktop/Flying_disc_freestyle_640x360.mp4");
    if (!video.isOpened()) {
        cout << "could not load video file ..." << endl;
        return -1;
    }
    
    Mat frame, object, frame_contours;
    Mat kernel_open = getStructuringElement(MORPH_RECT, Size(3,3));
    Mat kernel_dilate = getStructuringElement(MORPH_RECT, Size(5,5));
    
    namedWindow("flying_disc", WINDOW_AUTOSIZE);
    namedWindow("flying_disc_contours", WINDOW_AUTOSIZE);
    namedWindow("object", WINDOW_AUTOSIZE);
    
    while (video.read(frame)) {
        frame.copyTo(frame_contours);
        inRange(frame, Scalar(0,120,30), Scalar(80,255,180), object);
        morphologyEx(object, object, MORPH_OPEN, kernel_open);
        dilate(object, object, kernel_dilate);
        
        trackObject(object, roi);
        rectangle(frame, roi, Scalar(0,0,255));
        printAllContours(object, frame_contours);
        
        imshow("flying_disc", frame);
        imshow("object", object);
        imshow("flying_disc_contours", frame_contours);
        
        char c = waitKey(50);
        if (c == 27) {
            break;
        }
    }
    waitKey(0);
    video.release();
    return 0;
}

void printAllContours(Mat &object, Mat& frame)
{
    vector<vector<Point>> contours;
    vector<Vec4i> hireachy;
    findContours(object, contours, hireachy, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE);
    if (contours.size() > 0) {
        for (size_t t=0; t < contours.size(); t++) {
            rectangle(frame, boundingRect(contours[static_cast<int>(t)]), Scalar(0,0,255));
        }
    }
}

void trackObject(Mat &frame, Rect &roi)
{
    vector<vector<Point>> contours;
    vector<Vec4i> hireachy;
    findContours(frame, contours, hireachy, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE);
    if (contours.size() > 0) {
        double maxArea = 0.0;
        for (size_t t=0; t < contours.size(); t++) {
            double area = contourArea(contours[static_cast<int>(t)]);
            if (area > maxArea) {
                maxArea = area;
                roi = boundingRect(contours[static_cast<int>(t)]);
            }
        }
    }
    else {
        roi.x = roi.y = roi.height = roi.width = 0;
    }
}

效果展示