【练习6.7】设置cvCanny的不同参数处理图像，对比结果

题目要求：

通过设置cvCanny中好的低阈值和高阈值，使用三种不同的高低阈值比，分别为1.5：1 、2.75：1、4:1

a、设置高阈值小于50

b、设置50＜高阈值＜100

c、设置100＜高阈值＜150

e、设置200＜高阈值＜250

程序代码：

  1 // OpenCVExerciseTesting.cpp : 定义控制台应用程序的入口点。
  2 //
  3 //D:\\Work\\Work_Programming\\Source\\Image\\lena.jpg
  4
  5
  6 #include "stdafx.h"
  7 #include <cv.h>
  8 #include <highgui.h>
  9 #include <iostream>
 10
 11 #include <opencv2/legacy/legacy.hpp>
 12 //#pragma comment(lib, "opencv_legacy2411.lib")
 13
 14 using namespace cv;
 15 using namespace std;
 16
 17 //函数声明-->--->-->--->-->--->-->--->//
 18
 19
 20 //<--<--<--<--<--<--<--<--<--函数声明//
 21
 22 int _tmain(int argc, _TCHAR* argv[])
 23 {
 24     const char * soutceFile = "D:\\Work\\Work_Programming\\Source\\Image\\OpenCVExerciseImage\\第6章\\建筑.jpg";
 25     IplImage * image_Resource = cvLoadImage(soutceFile, CV_LOAD_IMAGE_GRAYSCALE);
 26     assert(image_Resource);
 27
 28     cvNamedWindow("原始图像", CV_WINDOW_NORMAL);
 29     cvNamedWindow("题目_a_1", CV_WINDOW_NORMAL);
 30     cvNamedWindow("题目_a_2", CV_WINDOW_NORMAL);
 31     cvNamedWindow("题目_a_3", CV_WINDOW_NORMAL);
 32     cvNamedWindow("题目_b_1", CV_WINDOW_NORMAL);
 33     cvNamedWindow("题目_b_2", CV_WINDOW_NORMAL);
 34     cvNamedWindow("题目_b_3", CV_WINDOW_NORMAL);
 35     cvNamedWindow("题目_c_1", CV_WINDOW_NORMAL);
 36     cvNamedWindow("题目_c_2", CV_WINDOW_NORMAL);
 37     cvNamedWindow("题目_c_3", CV_WINDOW_NORMAL);
 38     //cvNamedWindow("题目_d_1", CV_WINDOW_NORMAL);
 39     //cvNamedWindow("题目_d_2", CV_WINDOW_NORMAL);
 40     //cvNamedWindow("题目_d_3", CV_WINDOW_NORMAL);
 41     cvNamedWindow("题目_e_1", CV_WINDOW_NORMAL);
 42     cvNamedWindow("题目_e_2", CV_WINDOW_NORMAL);
 43     cvNamedWindow("题目_e_3", CV_WINDOW_NORMAL);
 44
 45     cvShowImage("原始图像", image_Resource);
 46
 47     //---------------------------a：开始--------------------------------//
 48
 49     IplImage * image_Result_a = cvCloneImage(image_Resource);
 50     cvZero(image_Result_a);
 51
 52     double highThresh = 10;
 53     double lowThresh = highThresh / 1.5;
 54
 55     cvCanny(image_Resource, image_Result_a, highThresh, lowThresh, 3);
 56     cvShowImage("题目_a_1", image_Result_a);
 57
 58     lowThresh = highThresh / 2.75;
 59     cvZero(image_Result_a);
 60
 61     cvCanny(image_Resource, image_Result_a, highThresh, lowThresh, 3);
 62     cvShowImage("题目_a_2", image_Result_a);
 63
 64     lowThresh = highThresh / 4.0;
 65     cvZero(image_Result_a);
 66
 67     cvCanny(image_Resource, image_Result_a, highThresh, lowThresh, 3);
 68     cvShowImage("题目_a_3", image_Result_a);
 69
 70     //---------------------------a：结束--------------------------------//
 71
 72     //---------------------------b：开始--------------------------------//
 73
 74     IplImage * image_Result_b = cvCloneImage(image_Resource);
 75     cvZero(image_Result_b);
 76
 77     highThresh = 80;
 78     lowThresh = highThresh / 1.5;
 79
 80     cvCanny(image_Resource, image_Result_b, highThresh, lowThresh, 3);
 81     cvShowImage("题目_b_1", image_Result_b);
 82
 83     lowThresh = highThresh / 2.75;
 84     cvZero(image_Result_b);
 85
 86     cvCanny(image_Resource, image_Result_b, highThresh, lowThresh, 3);
 87     cvShowImage("题目_b_2", image_Result_b);
 88
 89     lowThresh = highThresh / 4.0;
 90     cvZero(image_Result_b);
 91
 92     cvCanny(image_Resource, image_Result_b, highThresh, lowThresh, 3);
 93     cvShowImage("题目_b_3", image_Result_b);
 94
 95     //---------------------------b：结束--------------------------------//
 96
 97     //---------------------------c：开始--------------------------------//
 98
 99     IplImage * image_Result_c = cvCloneImage(image_Resource);
100     cvZero(image_Result_c);
101
102     highThresh = 130;
103     lowThresh = highThresh / 1.5;
104
105     cvCanny(image_Resource, image_Result_c, highThresh, lowThresh, 3);
106     cvShowImage("题目_c_1", image_Result_c);
107
108     lowThresh = highThresh / 2.75;
109     cvZero(image_Result_c);
110
111     cvCanny(image_Resource, image_Result_c, highThresh, lowThresh, 3);
112     cvShowImage("题目_c_2", image_Result_c);
113
114     lowThresh = highThresh / 4.0;
115     cvZero(image_Result_c);
116
117     cvCanny(image_Resource, image_Result_c, highThresh, lowThresh, 3);
118     cvShowImage("题目_c_3", image_Result_c);
119
120     //---------------------------c：结束--------------------------------//
121
122     //---------------------------e：开始--------------------------------//
123
124     IplImage * image_Result_e = cvCloneImage(image_Resource);
125     cvZero(image_Result_e);
126
127     highThresh = 245;
128     lowThresh = highThresh / 1.5;
129
130     cvCanny(image_Resource, image_Result_e, highThresh, lowThresh, 3);
131     cvShowImage("题目_e_1", image_Result_e);
132
133     lowThresh = highThresh / 2.75;
134     cvZero(image_Result_e);
135
136     cvCanny(image_Resource, image_Result_e, highThresh, lowThresh, 3);
137     cvShowImage("题目_e_2", image_Result_e);
138
139     lowThresh = highThresh / 4.0;
140     cvZero(image_Result_e);
141
142     cvCanny(image_Resource, image_Result_e, highThresh, lowThresh, 3);
143     cvShowImage("题目_e_3", image_Result_e);
144
145     //---------------------------e：结束--------------------------------//
146
147     cvWaitKey(0);
148
149     cvReleaseImage(&image_Resource);
150     cvReleaseImage(&image_Result_a);
151     cvReleaseImage(&image_Result_b);
152     cvReleaseImage(&image_Result_c);
153     cvReleaseImage(&image_Result_e);
154
155     cvDestroyAllWindows();
156
157     return 0;
158 }

结果图片：

要言妙道：

①Canny推荐的上下限阈值比为2:1到3:1之间