学习OpenCV：滤镜系列（2）——扩张&挤压

来源：互联网发布：java 剩余天数编辑：程序博客网时间：2024/04/28 10:04

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原理：凸透镜效果算法

#include <math.h>#include <opencv/cv.h>#include <opencv/highgui.h>using namespace cv;using namespace std;int main(){Mat src = imread("D:/img/face02.jpg",1);int width = src.cols;int heigh = src.rows;Point center(width/2,heigh/2);Mat img1(src.size(),CV_8UC3);Mat img2(src.size(),CV_8UC3);src.copyTo(img1);src.copyTo(img2);//【1】放大int R1 = sqrtf(width*width+heigh*heigh)/2; //直接关系到放大的力度,与R1成正比;for (int y=0; y<heigh; y++){uchar *img1_p = img1.ptr<uchar>(y);for (int x=0; x<width; x++){int dis = norm(Point(x,y)-center);if (dis<R1){int newX = (x-center.x)*dis/R1+center.x;int newY = (y-center.y)*dis/R1+center.y;img1_p[3*x]=src.at<uchar>(newY,newX*3);img1_p[3*x+1]=src.at<uchar>(newY,newX*3+1);img1_p[3*x+2]=src.at<uchar>(newY,newX*3+2);}}}//【2】挤压for (int y=0; y<heigh; y++){uchar *img2_p = img2.ptr<uchar>(y);for (int x=0; x<width; x++){double theta = atan2((double)(y-center.y),(double)(x-center.x));//使用atan出现问题~int R2 = sqrtf(norm(Point(x,y)-center))*8; //直接关系到挤压的力度，与R2成反比;int newX = center.x+(int)(R2*cos(theta));int newY = center.y+(int)(R2*sin(theta));if(newX<0) newX=0;else if(newX>=width) newX=width-1;if(newY<0) newY=0;else if(newY>=heigh) newY=heigh-1;img2_p[3*x]=src.at<uchar>(newY,newX*3);img2_p[3*x+1]=src.at<uchar>(newY,newX*3+1);img2_p[3*x+2]=src.at<uchar>(newY,newX*3+2);}}imshow("src",src);imshow("img1",img1);imshow("img2",img2);waitKey();imwrite("D:/img/扩张.jpg",img1);imwrite("D:/img/挤压.jpg",img2);}

原图：

扩张：

挤压：