卷積
模糊影象，影象邊緣，增強影象

常見卷積運算元：
Robert、sobel、拉普拉斯運算元

程式碼：

#include <opencv2/opencv.hpp>
#include <iostream>
#include <math.h>

using namespace cv;

int main(int argc,char ** argv)
{
    Mat src,dst;
    Mat kernel;

    char outwindow1[] = "out1";
    char outwindow2[] = "out2";
    char
 
 outwindow3[] = "out3";
    char outwindow4[] = "out4";
    char outwindow5[] = "out5";
    char outwindow6[] = "out6";
    src = imread("1.jpg");
    namedWindow("input window",CV_WINDOW_AUTOSIZE);
    imshow("input window",src);

    namedWindow(outwindow1,CV_WINDOW_AUTOSIZE);
    namedWindow(outwindow2,CV_WINDOW_AUTOSIZE);
    namedWindow(outwindow3,CV_WINDOW_AUTOSIZE);
    namedWindow(outwindow4,CV_WINDOW_AUTOSIZE);
    namedWindow(outwindow5,CV_WINDOW_AUTOSIZE);
    namedWindow(outwindow6,CV_WINDOW_AUTOSIZE);
    Mat kernel_x = (Mat_<int
 
>(2,2)<<1,0,0,-1);
    filter2D(src,dst,-1,kernel_x,Point(-1,-1),0.0);
    imshow(outwindow1,dst);
    Mat kernel_y = (Mat_<int>(2,2)<<0,1,-1,0);
    filter2D(src,dst,-1,kernel_y,Point(-1,-1),0.0);
    imshow(outwindow2,dst);
    //左右的差異
    Mat kernel2_x = (Mat_<int>(3,3)<<-1
 
,0,1,-2,0,2,-1,0,1);
    filter2D(src,dst,-1,kernel2_x,Point(-1,-1),0.0);
    imshow(outwindow3,dst);
    //上下差異
    Mat kernel2_y = (Mat_<int>(3,3)<<-1,-2,1,0,0,0,1,2,1);
    filter2D(src,dst,-1,kernel2_y,Point(-1,-1),0.0);
    imshow(outwindow4,dst);

    //拉普拉斯運算元
    Mat kernel3 = (Mat_<int>(3,3)<<0,-1,0,-1,4,-1,0,-1,0);
    filter2D(src,dst,-1,kernel3,Point(-1,-1),0.0);
    imshow(outwindow5,dst);

    int ksize = 0;
    int c = 0;
    int index = 0;
    while(true)
    {
        c = waitKey(500);
        if((char)c == 27)
        {
            break;
        }
        ksize = 4 + (index % 8) * 2 + 1;
        Mat kernel_auto = Mat::ones(Size(ksize,ksize),CV_32F)/float(ksize*ksize);
        filter2D(src,dst,-1,kernel_auto,Point(-1,-1),0.0);
        index ++;
        imshow(outwindow6,dst);
    }

    return 0;
}

效果：