学习OpenCV：滤镜系列（2）扩张&挤压

【原文：http://blog.csdn.net/yangtrees/article/details/9095731】 ============================================== 小熊不去实验室CSDN博客 ============================================== 原理：凸透镜效果算法 [cpp] view plaincopyprint? #includem

【原文：http://blog.csdn.net/yangtrees/article/details/9095731】

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小熊不去实验室CSDN博客

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原理：凸透镜效果算法

[cpp] view plaincopyprint?

1. #include
2. #include
3. #include
5. using namespace cv;
6. using namespace std;
8. int main()
9. {
10. Mat src = imread("D:/img/face02.jpg",1);
11. int width = src.cols;
12. int heigh = src.rows;
13. Point center(width/2,heigh/2);
14. Mat img1(src.size(),CV_8UC3);
15. Mat img2(src.size(),CV_8UC3);
16. src.copyTo(img1);
17. src.copyTo(img2);
19. //【1】放大
20. int R1 = sqrtf(width*width+heigh*heigh)/2; //直接关系到放大的力度,与R1成正比;
22. for (int y=0; y
23. {
24. uchar *img1_p = img1.ptr(y);
25. for (int x=0; x
26. {
27. int dis = norm(Point(x,y)-center);
28. if (dis
29. {
30. int newX = (x-center.x)*dis/R1+center.x;
31. int newY = (y-center.y)*dis/R1+center.y;
33. img1_p[3*x]=src.at(newY,newX*3);
34. img1_p[3*x+1]=src.at(newY,newX*3+1);
35. img1_p[3*x+2]=src.at(newY,newX*3+2);
36. }
37. }
38. }
40. //【2】挤压
41. for (int y=0; y
42. {
43. uchar *img2_p = img2.ptr(y);
44. for (int x=0; x
45. {
46. double theta = atan2((double)(y-center.y),(double)(x-center.x));//使用atan出现问题~
49. int R2 = sqrtf(norm(Point(x,y)-center))*8; //直接关系到挤压的力度，与R2成反比;
51. int newX = center.x+(int)(R2*cos(theta));
53. int newY = center.y+(int)(R2*sin(theta));
55. if(newX<0) newX=0;
56. else if(newX>=width) newX=width-1;
57. if(newY<0) newY=0;
58. else if(newY>=heigh) newY=heigh-1;
61. img2_p[3*x]=src.at(newY,newX*3);
62. img2_p[3*x+1]=src.at(newY,newX*3+1);
63. img2_p[3*x+2]=src.at(newY,newX*3+2);
64. }
65. }
66. imshow("src",src);
67. imshow("img1",img1);
68. imshow("img2",img2);
69. waitKey();
70. imwrite("D:/img/扩张.jpg",img1);
71. imwrite("D:/img/挤压.jpg",img2);
72. }

原图：

扩张：

挤压：