OpenCV直方图计算，以及颜色迁移

本文的前两个代码主要是来自于书本《OPenCV计算机视觉编程攻略》最后一个代码是根据前两个代码做的一个颜色迁移

黑白图片的直方图计算

////  main.cpp//  TextureFusion2////  Created by coriander on 10/14/17.//  Copyright © 2017 xiaowoCorp. All rights reserved.//#include <iostream>#include <opencv2/core/core.hpp>#include <opencv2/highgui/highgui.hpp>#include <opencv2/opencv.hpp>////////////filename format//r11 r12 r13//r21 r22 r23//r31 r32 r33//t1 t2 t3/////////using namespace std;class Histogram1D{private:    int histSize[1];//直方图中箱子的数目    float hranges[2];    const float*ranges[1];    int channels[1];public:    Histogram1D(){        histSize[0]=256;        hranges[0]=0.0;        hranges[1]=256;        ranges[0]=hranges;        channels[0]=0;    }    cv::Mat getHistogram(const  cv::Mat& image){        cv::Mat hist;        cv::calcHist(&image, 1, channels, cv::Mat(), hist, 1, histSize, ranges);        return  hist;    }    cv::Mat getHistogramImage(const cv::Mat &image,int zoom=1){        cv::Mat hist=getHistogram(image);        return getImageOfHistogram(hist,zoom);    }    static cv::Mat getImageOfHistogram(const cv::Mat &hist,int zoom){        double maxVal=0;        double minVal=0;        cv::minMaxLoc(hist, &minVal, &maxVal,0,0);        int histSize=hist.rows;        cv::Mat histImg(histSize*zoom,histSize*zoom,CV_8U,cv::Scalar(255));        int hpt=static_cast<int>(0.9*histSize);        for(int h=0;h<histSize;h++){            float binVal=hist.at<float>(h);            if(binVal >0){                int intensity=static_cast<int >(binVal*hpt/maxVal);                cv::line(histImg, cv::Point(h*zoom,histSize*zoom), cv::Point(h*zoom,(histSize-intensity)*zoom), cv::Scalar(0),zoom);            }        }        return histImg;    }};int main(){    cv::Mat image1=cv::imread("Mesh0.jpg",0);    Histogram1D h;    cv::Mat histo=h.getHistogram(image1);    for(int i=0;i<256;i++)        cout<<"value"<<i<<"="<<histo.at<float>(i)<<endl;    cv::namedWindow("Histgram");    cv::imshow("Histgram", h.getHistogramImage(image1));    cv::waitKey();    return 0;}