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Image Processing for Dummies with C# and GDI+ Part 2 - Convolution Filters

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7 Nov 2005CPOL8 min read 1.6M   15.4K   331  
The second in a series of articles which will build an image processing library in C# and GDI+.
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace CSharpFilters
{
	/// <summary>
	/// Summary description for Form1.
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		private System.Drawing.Bitmap m_Bitmap;
		private System.Drawing.Bitmap m_Undo;
		private System.Windows.Forms.MainMenu mainMenu1;
		private System.Windows.Forms.MenuItem menuItem1;
		private System.Windows.Forms.MenuItem menuItem4;
		private System.Windows.Forms.MenuItem FileLoad;
		private System.Windows.Forms.MenuItem FileSave;
		private System.Windows.Forms.MenuItem FileExit;
		private System.Windows.Forms.MenuItem FilterInvert;
		private System.Windows.Forms.MenuItem FilterGrayScale;
		private System.Windows.Forms.MenuItem FilterBrightness;
		private System.Windows.Forms.MenuItem FilterContrast;
		private System.Windows.Forms.MenuItem FilterGamma;
		private System.Windows.Forms.MenuItem FilterColor;
		private System.Windows.Forms.MenuItem menuItem2;
		private System.Windows.Forms.MenuItem Zoom25;
		private double Zoom = 1.0;
		private System.Windows.Forms.MenuItem Zoom50;
		private System.Windows.Forms.MenuItem Zoom100;
		private System.Windows.Forms.MenuItem Zoom150;
		private System.Windows.Forms.MenuItem Zoom200;
		private System.Windows.Forms.MenuItem Zoom300;
		private System.Windows.Forms.MenuItem Zoom500;
		private System.Windows.Forms.MenuItem menuItem3;
		private System.Windows.Forms.MenuItem FilterSmooth;
		private System.Windows.Forms.MenuItem GaussianBlur;
		private System.Windows.Forms.MenuItem MeanRemoval;
		private System.Windows.Forms.MenuItem Sharpen;
		private System.Windows.Forms.MenuItem EmbossLaplacian;
		private System.Windows.Forms.MenuItem EdgeDetectQuick;
		private System.Windows.Forms.MenuItem menuItem5;
		private System.Windows.Forms.MenuItem Undo;
		private System.Windows.Forms.MenuItem FilterCustom;
		/// <summary>
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			InitializeComponent();

			m_Bitmap= new Bitmap(2, 2);
		}

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.mainMenu1 = new System.Windows.Forms.MainMenu();
			this.menuItem1 = new System.Windows.Forms.MenuItem();
			this.FileLoad = new System.Windows.Forms.MenuItem();
			this.FileSave = new System.Windows.Forms.MenuItem();
			this.FileExit = new System.Windows.Forms.MenuItem();
			this.menuItem5 = new System.Windows.Forms.MenuItem();
			this.Undo = new System.Windows.Forms.MenuItem();
			this.menuItem4 = new System.Windows.Forms.MenuItem();
			this.FilterInvert = new System.Windows.Forms.MenuItem();
			this.FilterGrayScale = new System.Windows.Forms.MenuItem();
			this.FilterBrightness = new System.Windows.Forms.MenuItem();
			this.FilterContrast = new System.Windows.Forms.MenuItem();
			this.FilterGamma = new System.Windows.Forms.MenuItem();
			this.FilterColor = new System.Windows.Forms.MenuItem();
			this.menuItem3 = new System.Windows.Forms.MenuItem();
			this.FilterSmooth = new System.Windows.Forms.MenuItem();
			this.GaussianBlur = new System.Windows.Forms.MenuItem();
			this.MeanRemoval = new System.Windows.Forms.MenuItem();
			this.Sharpen = new System.Windows.Forms.MenuItem();
			this.EmbossLaplacian = new System.Windows.Forms.MenuItem();
			this.EdgeDetectQuick = new System.Windows.Forms.MenuItem();
			this.menuItem2 = new System.Windows.Forms.MenuItem();
			this.Zoom25 = new System.Windows.Forms.MenuItem();
			this.Zoom50 = new System.Windows.Forms.MenuItem();
			this.Zoom100 = new System.Windows.Forms.MenuItem();
			this.Zoom150 = new System.Windows.Forms.MenuItem();
			this.Zoom200 = new System.Windows.Forms.MenuItem();
			this.Zoom300 = new System.Windows.Forms.MenuItem();
			this.Zoom500 = new System.Windows.Forms.MenuItem();
			this.FilterCustom = new System.Windows.Forms.MenuItem();
			// 
			// mainMenu1
			// 
			this.mainMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.menuItem1,
																					  this.menuItem5,
																					  this.menuItem4,
																					  this.menuItem3,
																					  this.menuItem2});
			// 
			// menuItem1
			// 
			this.menuItem1.Index = 0;
			this.menuItem1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.FileLoad,
																					  this.FileSave,
																					  this.FileExit});
			this.menuItem1.Text = "File";
			// 
			// FileLoad
			// 
			this.FileLoad.Index = 0;
			this.FileLoad.Shortcut = System.Windows.Forms.Shortcut.CtrlL;
			this.FileLoad.Text = "Load";
			this.FileLoad.Click += new System.EventHandler(this.File_Load);
			// 
			// FileSave
			// 
			this.FileSave.Index = 1;
			this.FileSave.Shortcut = System.Windows.Forms.Shortcut.CtrlS;
			this.FileSave.Text = "Save";
			this.FileSave.Click += new System.EventHandler(this.File_Save);
			// 
			// FileExit
			// 
			this.FileExit.Index = 2;
			this.FileExit.Text = "Exit";
			this.FileExit.Click += new System.EventHandler(this.File_Exit);
			// 
			// menuItem5
			// 
			this.menuItem5.Index = 1;
			this.menuItem5.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.Undo});
			this.menuItem5.Text = "Edit";
			// 
			// Undo
			// 
			this.Undo.Index = 0;
			this.Undo.Text = "Undo";
			this.Undo.Click += new System.EventHandler(this.OnUndo);
			// 
			// menuItem4
			// 
			this.menuItem4.Index = 2;
			this.menuItem4.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.FilterInvert,
																					  this.FilterGrayScale,
																					  this.FilterBrightness,
																					  this.FilterContrast,
																					  this.FilterGamma,
																					  this.FilterColor});
			this.menuItem4.Text = "Filter";
			// 
			// FilterInvert
			// 
			this.FilterInvert.Index = 0;
			this.FilterInvert.Text = "Invert";
			this.FilterInvert.Click += new System.EventHandler(this.Filter_Invert);
			// 
			// FilterGrayScale
			// 
			this.FilterGrayScale.Index = 1;
			this.FilterGrayScale.Text = "GrayScale";
			this.FilterGrayScale.Click += new System.EventHandler(this.Filter_GrayScale);
			// 
			// FilterBrightness
			// 
			this.FilterBrightness.Index = 2;
			this.FilterBrightness.Text = "Brightness";
			this.FilterBrightness.Click += new System.EventHandler(this.Filter_Brightness);
			// 
			// FilterContrast
			// 
			this.FilterContrast.Index = 3;
			this.FilterContrast.Text = "Contrast";
			this.FilterContrast.Click += new System.EventHandler(this.Filter_Contrast);
			// 
			// FilterGamma
			// 
			this.FilterGamma.Index = 4;
			this.FilterGamma.Text = "Gamma";
			this.FilterGamma.Click += new System.EventHandler(this.Filter_Gamma);
			// 
			// FilterColor
			// 
			this.FilterColor.Index = 5;
			this.FilterColor.Text = "Color";
			this.FilterColor.Click += new System.EventHandler(this.Filter_Color);
			// 
			// menuItem3
			// 
			this.menuItem3.Index = 3;
			this.menuItem3.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.FilterSmooth,
																					  this.GaussianBlur,
																					  this.MeanRemoval,
																					  this.Sharpen,
																					  this.EmbossLaplacian,
																					  this.EdgeDetectQuick,
																					  this.FilterCustom});
			this.menuItem3.Text = "Convolution";
			// 
			// FilterSmooth
			// 
			this.FilterSmooth.Index = 0;
			this.FilterSmooth.Text = "Smooth";
			this.FilterSmooth.Click += new System.EventHandler(this.OnFilterSmooth);
			// 
			// GaussianBlur
			// 
			this.GaussianBlur.Index = 1;
			this.GaussianBlur.Text = "Gaussian Blur";
			this.GaussianBlur.Click += new System.EventHandler(this.OnGaussianBlur);
			// 
			// MeanRemoval
			// 
			this.MeanRemoval.Index = 2;
			this.MeanRemoval.Text = "Mean Removal";
			this.MeanRemoval.Click += new System.EventHandler(this.OnMeanRemoval);
			// 
			// Sharpen
			// 
			this.Sharpen.Index = 3;
			this.Sharpen.Text = "Sharpen";
			this.Sharpen.Click += new System.EventHandler(this.OnSharpen);
			// 
			// EmbossLaplacian
			// 
			this.EmbossLaplacian.Index = 4;
			this.EmbossLaplacian.Text = "EmbossLaplacian";
			this.EmbossLaplacian.Click += new System.EventHandler(this.OnEmbossLaplacian);
			// 
			// EdgeDetectQuick
			// 
			this.EdgeDetectQuick.Index = 5;
			this.EdgeDetectQuick.Text = "EdgeDetectQuick";
			this.EdgeDetectQuick.Click += new System.EventHandler(this.OnEdgeDetectQuick);
			// 
			// menuItem2
			// 
			this.menuItem2.Index = 4;
			this.menuItem2.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.Zoom25,
																					  this.Zoom50,
																					  this.Zoom100,
																					  this.Zoom150,
																					  this.Zoom200,
																					  this.Zoom300,
																					  this.Zoom500});
			this.menuItem2.Text = "Zoom";
			// 
			// Zoom25
			// 
			this.Zoom25.Index = 0;
			this.Zoom25.Text = "25%";
			this.Zoom25.Click += new System.EventHandler(this.OnZoom25);
			// 
			// Zoom50
			// 
			this.Zoom50.Index = 1;
			this.Zoom50.Text = "50%";
			this.Zoom50.Click += new System.EventHandler(this.OnZoom50);
			// 
			// Zoom100
			// 
			this.Zoom100.Index = 2;
			this.Zoom100.Text = "100%";
			this.Zoom100.Click += new System.EventHandler(this.OnZoom100);
			// 
			// Zoom150
			// 
			this.Zoom150.Index = 3;
			this.Zoom150.Text = "150%";
			this.Zoom150.Click += new System.EventHandler(this.OnZoom150);
			// 
			// Zoom200
			// 
			this.Zoom200.Index = 4;
			this.Zoom200.Text = "200%";
			this.Zoom200.Click += new System.EventHandler(this.OnZoom200);
			// 
			// Zoom300
			// 
			this.Zoom300.Index = 5;
			this.Zoom300.Text = "300%";
			this.Zoom300.Click += new System.EventHandler(this.OnZoom300);
			// 
			// Zoom500
			// 
			this.Zoom500.Index = 6;
			this.Zoom500.Text = "500%";
			this.Zoom500.Click += new System.EventHandler(this.OnZoom500);
			// 
			// FilterCustom
			// 
			this.FilterCustom.Index = 6;
			this.FilterCustom.Text = "Custom";
			this.FilterCustom.Click += new System.EventHandler(this.OnFilterCustom);
			// 
			// Form1
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
			this.BackColor = System.Drawing.SystemColors.ControlLightLight;
			this.ClientSize = new System.Drawing.Size(488, 421);
			this.Menu = this.mainMenu1;
			this.Name = "Form1";
			this.Text = "Graphic Filters For Dummies";
			this.Load += new System.EventHandler(this.Form1_Load);

		}
		#endregion

		/// <summary>
		/// The main entry point for the application.
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new Form1());
		}

		protected override void OnPaint (PaintEventArgs e)
		{
			Graphics g = e.Graphics;

			g.DrawImage(m_Bitmap, new Rectangle(this.AutoScrollPosition.X, this.AutoScrollPosition.Y, (int)(m_Bitmap.Width*Zoom), (int)(m_Bitmap.Height * Zoom)));
		}

		private void Form1_Load(object sender, System.EventArgs e)
		{
		}

		private void File_Load(object sender, System.EventArgs e)
		{
			OpenFileDialog openFileDialog = new OpenFileDialog();

			openFileDialog.InitialDirectory = "c:\\" ;
			openFileDialog.Filter = "Bitmap files (*.bmp)|*.bmp|Jpeg files (*.jpg)|*.jpg|All valid files (*.bmp/*.jpg)|*.bmp/*.jpg";
			openFileDialog.FilterIndex = 2 ;
			openFileDialog.RestoreDirectory = true ;

			if(DialogResult.OK == openFileDialog.ShowDialog())
			{
				m_Bitmap = (Bitmap)Bitmap.FromFile(openFileDialog.FileName, false);
				this.AutoScroll = true;
				this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
				this.Invalidate();
			}
		}

		private void File_Save(object sender, System.EventArgs e)
		{
			SaveFileDialog saveFileDialog = new SaveFileDialog();

			saveFileDialog.InitialDirectory = "c:\\" ;
			saveFileDialog.Filter = "Bitmap files (*.bmp)|*.bmp|Jpeg files (*.jpg)|*.jpg|All valid files (*.bmp/*.jpg)|*.bmp/*.jpg" ;
			saveFileDialog.FilterIndex = 1 ;
			saveFileDialog.RestoreDirectory = true ;

			if(DialogResult.OK == saveFileDialog.ShowDialog())
			{
				m_Bitmap.Save(saveFileDialog.FileName);
			}
		}

		private void File_Exit(object sender, System.EventArgs e)
		{
			this.Close();
		}

		private void Filter_Invert(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.Invert(m_Bitmap))
				this.Invalidate();
		}

		private void Filter_GrayScale(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.GrayScale(m_Bitmap))
				this.Invalidate();
		}

		private void Filter_Brightness(object sender, System.EventArgs e)
		{
			Parameter dlg = new Parameter();
			dlg.nValue = 0;

			if (DialogResult.OK == dlg.ShowDialog())
			{
				m_Undo = (Bitmap)m_Bitmap.Clone();
				if(BitmapFilter.Brightness(m_Bitmap, dlg.nValue))
					this.Invalidate();
			}
		}

		private void Filter_Contrast(object sender, System.EventArgs e)
		{
			Parameter dlg = new Parameter();
			dlg.nValue = 0;

			if (DialogResult.OK == dlg.ShowDialog())
			{
				m_Undo = (Bitmap)m_Bitmap.Clone();
				if(BitmapFilter.Contrast(m_Bitmap, (sbyte)dlg.nValue))
					this.Invalidate();
			}
		
		}

		private void Filter_Gamma(object sender, System.EventArgs e)
		{
			GammaInput dlg = new GammaInput();
			dlg.red = dlg.green = dlg.blue = 1;

			if (DialogResult.OK == dlg.ShowDialog())
			{
				m_Undo = (Bitmap)m_Bitmap.Clone();
				if(BitmapFilter.Gamma(m_Bitmap, dlg.red, dlg.green, dlg.blue))
					this.Invalidate();
			}
		}

		private void Filter_Color(object sender, System.EventArgs e)
		{
			ColorInput dlg = new ColorInput();
			dlg.red = dlg.green = dlg.blue = 0;

			if (DialogResult.OK == dlg.ShowDialog())
			{
				m_Undo = (Bitmap)m_Bitmap.Clone();
				if(BitmapFilter.Color(m_Bitmap, dlg.red, dlg.green, dlg.blue))
					this.Invalidate();
			}
		
		}

		private void OnZoom25(object sender, System.EventArgs e)
		{
			Zoom = .25;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom50(object sender, System.EventArgs e)
		{
			Zoom = .5;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom100(object sender, System.EventArgs e)
		{
			Zoom = 1.0;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom150(object sender, System.EventArgs e)
		{
			Zoom = 1.5;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom200(object sender, System.EventArgs e)
		{
			Zoom = 2.0;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom300(object sender, System.EventArgs e)
		{
			Zoom = 3.0;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnZoom500(object sender, System.EventArgs e)
		{
			Zoom = 5;
			this.AutoScrollMinSize = new Size ((int)(m_Bitmap.Width * Zoom), (int)(m_Bitmap.Height * Zoom));
			this.Invalidate();
		}

		private void OnFilterSmooth(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.Smooth(m_Bitmap, 1))
				this.Invalidate();
		}

		private void OnGaussianBlur(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.GaussianBlur(m_Bitmap, 4))
				this.Invalidate();
		}

		private void OnMeanRemoval(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.MeanRemoval(m_Bitmap, 9))
				this.Invalidate();
		}

		private void OnSharpen(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.Sharpen(m_Bitmap, 11))
				this.Invalidate();
		}

		private void OnEmbossLaplacian(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.EmbossLaplacian(m_Bitmap))
				this.Invalidate();
		}

		private void OnEdgeDetectQuick(object sender, System.EventArgs e)
		{
			m_Undo = (Bitmap)m_Bitmap.Clone();
			if(BitmapFilter.EdgeDetectQuick(m_Bitmap))
				this.Invalidate();
		}

		private void OnUndo(object sender, System.EventArgs e)
		{
			Bitmap temp = (Bitmap)m_Bitmap.Clone();
			m_Bitmap = (Bitmap)m_Undo.Clone();
			m_Undo = (Bitmap)temp.Clone();
			this.Invalidate();
		}

		private void OnFilterCustom(object sender, System.EventArgs e)
		{
			Convolution dlg = new Convolution();

			if (DialogResult.OK == dlg.ShowDialog())
			{
				m_Undo = (Bitmap)m_Bitmap.Clone();
				if(BitmapFilter.Conv3x3(m_Bitmap, dlg.Matrix))
					this.Invalidate();
			}
		
		}

	}
}

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This article is part of the series 'Image Processing for Dummies with C# and GDI+ View All

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer (Senior)
Australia Australia
Programming computers ( self taught ) since about 1984 when I bought my first Apple ][. Was working on a GUI library to interface Win32 to Python, and writing graphics filters in my spare time, and then building n-tiered apps using asp, atl and asp.net in my job at Dytech. After 4 years there, I've started working from home, at first for Code Project and now for a vet telemedicine company. I owned part of a company that sells client education software in the vet market, but we sold that and I worked for the owners for five years before leaving to get away from the travel, and spend more time with my family. I now work for a company here in Hobart, doing all sorts of Microsoft based stuff in C++ and C#, with a lot of T-SQL in the mix.

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