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

using namespace std;
using namespace cv;

int minh,maxh,mins,maxs,minv,maxv;
void helptext()
{
    cout << "B——黑色\n";
    cout << "H——灰色\n";
    cout << "W——白色\n";
    cout << "R——紅色\n";
    cout << "O——橙色\n";
    cout << "Y——黃色\n";
    cout << "G——綠色\n";
    cout << "L——藍色\n";
    cout << "P——紫色\n";
    cout << "輸入要求識別的顏色對應的字母:" ;
}

//各種顏色HSV數值設定
void deal(char color)
{
        switch(color){
    case 'B':
        minh = 0;
        maxh = 180;
        mins = 0;
        maxs = 255;
        minv = 0;
        maxv = 46;
        break;
    case 'H':
        minh = 0;
        maxh = 180;
        mins = 0;
        maxs = 43;
        minv = 46;
        maxv = 220;
        break;
    case 'W':
        minh = 0;
        maxh = 180;
        mins = 0;
        maxs = 30;
        minv = 221;
        maxv = 255;
        break;
    case 'R':
        minh = 0;
        maxh = 10;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    case 'O':
        minh = 11;
        maxh = 25;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    case 'Y':
        minh = 26;
        maxh = 25;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    case 'G':
        minh = 35;
        maxh = 77;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    case 'L':
        minh = 100;
        maxh = 124;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    case 'P':
        minh = 125;
        maxh = 155;
        mins = 43;
        maxs = 255;
        minv = 46;
        maxv = 255;
        break;
    default:
        cout << "輸入錯誤" << endl;
        exit(0);
    }
}

int main(   )
{
    VideoCapture cap(1); //呼叫攝像頭，0為計算機攝像頭，1為外接USB攝像頭
	             
    Mat special;
	  
    helptext();

    char color;
    cin >> color;
    deal(color);


    while(true){
        	
	Mat frame;              //儲存每一幀的影象

        cap >> frame;        //讀取當前幀

        Mat fhsv;
        
		cvtColor(frame,fhsv,COLOR_BGR2HSV);   //將影象轉換為HSV模型
        
        inRange(fhsv,Scalar(minh,mins,minv),Scalar(maxh,maxs,maxv),special);          //找尋在要求區間內的顏色
           
		imshow("[pic]",special);
		 
        imshow("Original", frame); //show the original image    
    
		if(waitKey(30) >= 0)
			break;
    }
	
    return 0;
}
 

執行結果：

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