//該程式碼實現白平衡演算法中的灰度世界法，能有效改善影象發紅發藍發綠的現象；
  
 #include <opencv2/opencv.hpp>
 using namespace cv;
 
 int main()
 {
      Mat g_srcImage,dstImage;
     vector<Mat> g_vChannels;
    g_srcImage = imread("C:/Users/Administrator/Desktop/區分高架定位/01.jpg");
     imshow("原圖",g_srcImage);
     //waitKey(0);
 
     //分離通道
     split(g_srcImage,g_vChannels);
     Mat imageBlueChannel = g_vChannels.at(0);
     Mat imageGreenChannel = g_vChannels.at(1);     
    Mat imageRedChannel = g_vChannels.at(2);
 
     double imageBlueChannelAvg=0;
     double imageGreenChannelAvg=0;
     double imageRedChannelAvg=0;
 
     //求各通道的平均值
     imageBlueChannelAvg = mean(imageBlueChannel)[0];
     imageGreenChannelAvg = mean(imageGreenChannel)[0];
     imageRedChannelAvg = mean(imageRedChannel)[0];
 
     //求出個通道所佔增益
     double K = (imageRedChannelAvg+imageGreenChannelAvg+imageRedChannelAvg)/3;
     double Kb = K/imageBlueChannelAvg;
     double Kg = K/imageGreenChannelAvg;
     double Kr = K/imageRedChannelAvg;
 
     //更新白平衡後的各通道BGR值
     addWeighted(imageBlueChannel,Kb,0,0,0,imageBlueChannel);
     addWeighted(imageGreenChannel,Kg,0,0,0,imageGreenChannel);
     addWeighted(imageRedChannel,Kr,0,0,0,imageRedChannel);
 
     merge(g_vChannels,dstImage);//影象各通道合併
     imshow("白平衡後圖",dstImage);
     waitKey(0);
    return 0;
 }