三角波形扭曲：

void sinwave(cv::Mat& src,cv::Mat& dst)
{
    dst.create(src.rows, src.cols, CV_8UC3);
    dst.setTo(0);

    src.copyTo(dst);

    int PI = 3.1415;

    int RANGE = dst.cols/2;

    for (int i = 0; i < dst.rows; i++) {
        double temp = (dst.cols - RANGE) / 2 + (dst.cols - RANGE) * sin((2 * PI * i) / dst.rows + PI) / 2;
        for (int j = int(temp + 0.5); j < RANGE + temp; j++) {
            int m = (int)((j - temp) * (src.cols) / RANGE);
            if (m >= src.cols)
                m = src.cols - 1;
            if (m < 0)
                m = 0;
            dst.at<Vec3b>(i, j)[0] = src.at<Vec3b>(i, m)[0];
            dst.at<Vec3b>(i, j)[1] = src.at<Vec3b>(i, m)[1];
            dst.at<Vec3b>(i, j)[2] = src.at<Vec3b>(i, m)[2];
        }
    }
}

效果：

 

 

鱼眼扭曲：

void fisheye(cv::Mat& src,cv::Mat& dst)
{
    dst.create(src.rows, src.cols, CV_8UC3);
    dst.setTo(0);

    int PI = 3.1415;

    /* fish eye*/
    for (int id = 0; id < dst.rows; id++) {
        for (int jd = 0; jd < dst.cols; jd++) {
            double xd = jd * 2.0 / dst.cols - 1.0;
            double yd = id * 2.0 / dst.cols - 1.0;
            double rd = sqrt(xd * xd + yd * yd);
            double phid = atan2(yd, xd);
            double xs = asin(rd) * 2 / PI * cos(phid);
            double ys = asin(rd) * 2 / PI * sin(phid);
            int is = round((ys + 1.0) * dst.rows / 2.0);
            int js = round((xs + 1.0) * dst.cols / 2.0);
            if (is > dst.rows || is < 0 || js>dst.cols || js < 0){
                is = id;
                js = jd;
            }
            dst.at<Vec3b>(id, jd)[0] = src.at<Vec3b>(is, js)[0];
            dst.at<Vec3b>(id, jd)[1] = src.at<Vec3b>(is, js)[1];
            dst.at<Vec3b>(id, jd)[2] = src.at<Vec3b>(is, js)[2];
        }
    }
}

效果：