OpenCv 029---快速的图像边缘滤波算法

1 前备知识

    高斯双边模糊与mean shift均值模糊两种边缘保留滤波算法，都因为计算量比较大，无法实时实现图像边缘保留滤波，限制了它们的使用场景，OpenCV中还实现了一种快速的边缘保留滤波算法。高斯双边与mean shift均值在计算时候使用五维向量是其计算量大速度慢的根本原因，该算法通过等价变换到低纬维度空间，实现了数据降维与快速计算。

2 所用到的主要OpenCv API

/** @brief Filtering is the fundamental operation in image and video processing. Edge-preserving smoothing
filters are used in many different applications @cite EM11 .

@param src Input 8-bit 3-channel image.
@param dst Output 8-bit 3-channel image.
@param flags Edge preserving filters:
-   **RECURS_FILTER** = 1
-   **NORMCONV_FILTER** = 2
@param sigma_s Range between 0 to 200.
@param sigma_r Range between 0 to 1.
 */
CV_EXPORTS_W void edgePreservingFilter(InputArray src, OutputArray dst, int flags = 1,
        float sigma_s = 60, float sigma_r = 0.4f);

3 程序代码

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

using namespace cv;
using namespace std;

int main(int artc, char** argv) {
    Mat src = imread("images/example.png");
    if (src.empty()) {
        printf("could not load image...\n");
        return -1;
    }
    namedWindow("input", CV_WINDOW_AUTOSIZE);
    imshow("input", src);

    Mat dst;
    double tt = getTickCount();
    edgePreservingFilter(src, dst, 1, 60, 0.44);
    double end = (getTickCount() - tt) / getTickFrequency();
    printf("time consume : %f\n ", end);
    imshow("result", dst);

    waitKey(0);
    return 0;
}

4 运行结果

5 扩展及注意事项

6*搬运工