【opencv练习07 - 滤波器（锐化）】

void Sharpen(const Mat& myImage, Mat& Result){    CV_Assert( myImage.depth() != sizeof(uchar));    Result.create(myImage.size(), myImage.type());    const int nChannels = myImage.channels();    for(int j = 1; j < myImage.rows -1 ; ++j)    {        const uchar* previous = myImage.ptr<uchar>(j-1);            const uchar* current  = myImage.ptr<uchar>(j);        const uchar* next     = myImage.ptr<uchar>(j+1);        uchar* output = Result.ptr<uchar>(j);                       for(int i = nChannels; i < nChannels * (myImage.cols -1); ++i)        {            *output++ = saturate_cast<uchar>(5 * current[i] - current[ i- nChannels] - current[i + nChannels] - previous[i] - next[i]);        }    }    Result.row(0).setTo(Scalar(0));    Result.row(Result.rows -1).setTo(Scalar(0));    Result.col(0).setTo(Scalar(0));    Result.col(Result.cols -1).setTo(Scalar(0));}void main1(void){    Mat image;    Mat out_image;    Mat out_image_filter2D;    double t[2];    image = imread("YY01.jpg",CV_LOAD_IMAGE_COLOR);             t[0] = (double)getTickCount();    Sharpen(image,out_image);    t[0] = ((double)getTickCount() - t[0])/getTickFrequency();    imshow("Disp YY",image);                        imshow("Disp Sharpen_YY",out_image);                Mat kern = (Mat_<char>(3,3)<<0,-1, 0,                                 -1, 5,-1,                                  0,-1, 0);    t[1] = (double)getTickCount();    filter2D(image,out_image_filter2D,image.depth(), kern);    t[1] = ((double)getTickCount() - t[1])/getTickFrequency();    imshow("Disp filter2D_YY",out_image);           //show    cout<<"方法 【手工滤波器】—— Times passed in Second: "<<t[0]<<endl;    cout<<"方法 【filter2D 滤波器】—— Times passed in Second: "<<t[1]<<endl;    waitKey(0);}

经过OpenCV优化的滤波器速度，明显提高了一个数量级！

滤波器功能： 图像锐化