OpenCV求得圖像的最大連通域

直接貼代碼了。在寫的時候借鑒了網上的一些代碼，可是忘記保留鏈接了，所以此處向可能的貢獻者致謝。

1. #include <cv.h>
2. #include <highgui.h>
3. #include <vector>
4. #include <algorithm>
5. using namespace std;
7. #pragma comment( lib, "cv.lib" )
8. #pragma comment( lib, "cxcore.lib" )
9. #pragma comment( lib, "highgui.lib" )
11. int main()
12. {
13. IplImage *src = cvLoadImage("lena.jpg", CV_LOAD_IMAGE_COLOR);
14. cvNamedWindow("原始圖像");
15. cvShowImage("原始圖像", src);
17. IplImage* dst=cvCreateImage(cvSize(src->width,src->height),IPL_DEPTH_8U,1);
18. cvCvtColor(src,dst,CV_BGR2GRAY);
19. cvNamedWindow("灰度圖像");
20. cvShowImage("灰度圖像", src);
22. cvThreshold(dst, dst, 0.0, 255.0, CV_THRESH_BINARY | CV_THRESH_OTSU);//OTSU二值化
23. IplConvKernel *element = cvCreateStructuringElementEx(5, 5, 0, 0, CV_SHAPE_ELLIPSE);
24. cvMorphologyEx(dst, dst, NULL, element, CV_MOP_OPEN);//開運算，去除比結構元素小的點
25. cvReleaseStructuringElement(&element);
26. cvNamedWindow("二值圖像");
27. cvShowImage("二值圖像", dst);
29. int w,h;
30. CvSize sz = cvGetSize(dst);
32. int color = 254;//不對0計數，不可能為255，所以254
33. for (w=0; w<sz.width; w++)
34. {
35. for (h=0; h<sz.height; h++)
36. {
37. if (color > 0)
38. {
39. if (CV_IMAGE_ELEM(dst, unsigned char, h, w) == 255)
40. {
41. //把連通域標記上顏色
42. cvFloodFill(dst, cvPoint(w,h), CV_RGB( color,color,color));
43. color--;
44. }
45. }
46. }
47. }
48. cvNamedWindow("標記顏色後的圖像");
49. cvShowImage("標記顏色後的圖像", dst);
51. int colorsum[255] = {0};
52. for (w=0; w<sz.width; w++)
53. {
54. for (h=0; h<sz.height; h++)
55. {
56. if (CV_IMAGE_ELEM(dst, unsigned char, h, w) > 0)
57. {
58. colorsum[CV_IMAGE_ELEM(dst, unsigned char, h, w)]++;//統計每種顏色的數量
59. }
60. }
61. }
62. vector<int> v1(colorsum, colorsum+255);//用數組初始化vector
63. //求出最多數量的染色，注意max_element的使用方法
64. int maxcolorsum = max_element(v1.begin(), v1.end()) - v1.begin();
65. printf("%d\n",maxcolorsum);
67. for (w=0; w<sz.width; w++)
68. {
69. for (h=0; h<sz.height; h++)
70. {
71. if (CV_IMAGE_ELEM(dst, unsigned char, h, w) == maxcolorsum)
72. {
73. CV_IMAGE_ELEM(dst, unsigned char, h, w) = 255;
74. }
75. else
76. {
77. CV_IMAGE_ELEM(dst, unsigned char, h, w) = 0;
78. }
79. }
80. }
81. cvNamedWindow("最大連通域圖");
82. cvShowImage("最大連通域圖", dst);
84. cvWaitKey(0);
85. cvDestroyAllWindows();
86. cvReleaseImage(&src);
87. cvReleaseImage(&dst);
89. return 0;
90. }

測試圖像采用標准的Lena圖像，測試結果為：