一杯清酒邀明月
天下本无事,庸人扰之而烦耳。

 

 1 #include "opencv2/highgui/highgui.hpp"
 2 #include "opencv2/imgproc/imgproc.hpp"
 3 #include <iostream>
 4 #include <stdio.h>
 5 
 6 using namespace std;
 7 using namespace cv;
 8 
 9 /** @函数 main */
10 int main( int argc, char** argv )
11 {
12   Mat src, dst;
13 
14  /// 装载图像
15  src = imread( argv[1], 1 );
16 
17  if( !src.data )
18    { return -1; }
19 
20  /// 分割成3个单通道图像 ( R, G 和 B )
21  vector<Mat> rgb_planes;
22  split( src, rgb_planes );
23 
24  /// 设定bin数目
25  int histSize = 255;
26 
27  /// 设定取值范围 ( R,G,B) )
28  float range[] = { 0, 255 } ;
29  const float* histRange = { range };
30 
31  bool uniform = true; bool accumulate = false;
32 
33  Mat r_hist, g_hist, b_hist;
34 
35  /// 计算直方图:
36  calcHist( &rgb_planes[0], 1, 0, Mat(), r_hist, 1, &histSize, &histRange, uniform, accumulate );
37  calcHist( &rgb_planes[1], 1, 0, Mat(), g_hist, 1, &histSize, &histRange, uniform, accumulate );
38  calcHist( &rgb_planes[2], 1, 0, Mat(), b_hist, 1, &histSize, &histRange, uniform, accumulate );
39 
40  // 创建直方图画布
41  int hist_w = 400; int hist_h = 400;
42  int bin_w = cvRound( (double) hist_w/histSize );
43 
44  Mat histImage( hist_w, hist_h, CV_8UC3, Scalar( 0,0,0) );
45 
46  /// 将直方图归一化到范围 [ 0, histImage.rows ]
47  normalize(r_hist, r_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
48  normalize(g_hist, g_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
49  normalize(b_hist, b_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
50 
51  /// 在直方图画布上画出直方图
52  for( int i = 1; i < histSize; i++ )
53    {
54      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(r_hist.at<float>(i-1)) ) ,
55                       Point( bin_w*(i), hist_h - cvRound(r_hist.at<float>(i)) ),
56                       Scalar( 0, 0, 255), 2, 8, 0  );
57      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(g_hist.at<float>(i-1)) ) ,
58                       Point( bin_w*(i), hist_h - cvRound(g_hist.at<float>(i)) ),
59                       Scalar( 0, 255, 0), 2, 8, 0  );
60      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(b_hist.at<float>(i-1)) ) ,
61                       Point( bin_w*(i), hist_h - cvRound(b_hist.at<float>(i)) ),
62                       Scalar( 255, 0, 0), 2, 8, 0  );
63     }
64 
65  /// 显示直方图
66  namedWindow("calcHist Demo", CV_WINDOW_AUTOSIZE );
67  imshow("calcHist Demo", histImage );
68 
69  waitKey(0);
70 
71  return 0;
72 
73 }
posted on 2020-01-09 13:22  一杯清酒邀明月  阅读(220)  评论(0编辑  收藏  举报