C# OpenCvSharp 图片模糊检测（拉普拉斯算子）

目录

效果

项目

代码

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参考 

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效果

项目

VS2022

.net framework 4.8

OpenCvSharp 4.8

代码

//
// 摘要:
//     Calculates the Laplacian of an image
//
// 参数:
//   src:
//     Source image
//
//   dst:
//     Destination image; will have the same size and the same number of channels as
//     src
//
//   ddepth:
//     The desired depth of the destination image
//
//   ksize:
//     The aperture size used to compute the second-derivative filters
//
//   scale:
//     The optional scale factor for the computed Laplacian values (by default, no scaling
//     is applied
//
//   delta:
//     The optional delta value, added to the results prior to storing them in dst
//
//   borderType:
//     The pixel extrapolation method
public static void Laplacian(InputArray src, OutputArray dst, MatType ddepth, int ksize = 1, double scale = 1.0, double delta = 0.0, BorderTypes borderType = BorderTypes.Reflect101)

//
// 摘要:
//     computes mean value and standard deviation of all or selected array elements
//
// 参数:
//   src:
//     The source array; it should have 1 to 4 channels (so that the results can be
//     stored in Scalar's)
//
//   mean:
//     The output parameter: computed mean value
//
//   stddev:
//     The output parameter: computed standard deviation
//
//   mask:
//     The optional operation mask
public static void MeanStdDev(InputArray src, out Scalar mean, out Scalar stddev, InputArray? mask = null)

using OpenCvSharp;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Windows.Forms.VisualStyles;
using static System.Net.Mime.MediaTypeNames;
 
namespace OpenCvSharp_模糊检测_拉普拉斯算子_
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        string fileFilter = "*.*|*.bmp;*.jpg;*.jpeg;*.tiff;*.tiff;*.png";
        string image_path = "";
        Mat image = new Mat();
        Mat gray = new Mat();
        Mat laplacian = new Mat();
 
        double threshold = 100;
        double measure = 0;
 
        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Filter = fileFilter;
            if (ofd.ShowDialog() != DialogResult.OK) return;
            pictureBox1.Image = null;
            image_path = ofd.FileName;
            pictureBox1.Image = new Bitmap(image_path);
            textBox1.Text = "";
            image = new Mat(image_path);
        }
 
        private void button3_Click(object sender, EventArgs e)
        {
            if (image_path == "")
            {
                return;
            }
 
            Cv2.CvtColor(image, gray, ColorConversionCodes.BGR2GRAY);
 
            Cv2.Laplacian(gray, laplacian, gray.Type(), 3, 1, 0, BorderTypes.Default);
 
            Cv2.MeanStdDev(laplacian, out var mean, out var stddev);
 
            measure = stddev.Val0 * stddev.Val0;
 
            if (measure > threshold)
            {
                textBox1.Text = "不模糊，拉普拉斯算子方差： " + measure.ToString();
            }
            else
            {
                textBox1.Text = "模糊，拉普拉斯算子方差： " + measure.ToString();
            }
 
        }
    }
}

下载 

Demo下载

参考 

模糊度检测算法来自 ：https://pyimagesearch.com/2015/09/07/blur-detection-with-opencv/