Notes

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using AForge.Imaging.Filters;


namespace first
{
public partial class Form1 : Form
{
Bitmap originalImage;

public Form1()
{
InitializeComponent();
}


private void openToolStripMenuItem_Click(object sender, EventArgs e)
{
OpenFileDialog openDialog = new OpenFileDialog();
if (openDialog.ShowDialog() == DialogResult.OK)
{
originalImage = new Bitmap(openDialog.FileName); // take a file convert it into image, bitmap is a class
pictureBox1.Image = originalImage;
}

}

private void button1_Click(object sender, EventArgs e)
{
//convert the image into gray scale
Bitmap grayImage = Grayscale.CommonAlgorithms.BT709.Apply(originalImage);
Threshold bwObject = new Threshold();
Bitmap bwImage = bwObject.Apply(grayImage);
pictureBox2.Image = bwImage;

}

private void button2_Click(object sender, EventArgs e)
{
//convert to edged image
Bitmap eImage = Grayscale.CommonAlgorithms.BT709.Apply(originalImage);
HomogenityEdgeDetector edgeImg = new HomogenityEdgeDetector();
Bitmap edImg = edgeImg.Apply(eImage);
pictureBox2.Image = edImg;
}

private void button3_Click(object sender, EventArgs e)
{
Bitmap img = Grayscale.CommonAlgorithms.BT709.Apply(originalImage);
pictureBox2.Image = img;
}

bool isSkin(Color c)
{
return (c.R > 95 && c.G > 40 && c.B > 20) &&
(Math.Max(c.R, Math.Max(c.G, c.R)) -
Math.Min(c.R, Math.Min(c.G, c.B)))>15 &&
(Math.Abs(c.R - c.G) > 15 && c.R > c.G && c.R > c.G);
}

private void button4_Click(object sender, EventArgs e)
{
Bitmap copiedImage = (Bitmap)originalImage.Clone();
// to get the colour of the pixel passed as parameter
for(int x=0;x< originalImage.Width; x++)
{
for(int y = 0; y < originalImage.Height; y++)
{
if (!isSkin(copiedImage.GetPixel(x, y)))
{
copiedImage.SetPixel(x, y, Color.Black);
}
}
}
copiedImage = Grayscale.CommonAlgorithms.BT709.Apply(copiedImage);
Threshold bwObj = new Threshold(50);
copiedImage = bwObj.Apply(copiedImage);
pictureBox2.Image = copiedImage;

}
}
}