DisplayMagician/DisplayMagician/ImageUtils.cs

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DisplayMagician
{
    public static class ImageUtils
    {
        public static Image RoundCorners(Image StartImage, int CornerRadius)
        {
            CornerRadius *= 2;
            Bitmap RoundedImage = new Bitmap(StartImage.Width, StartImage.Height);
            using (Graphics g = Graphics.FromImage(RoundedImage))
            {
                g.Clear(Color.Transparent);
                g.SmoothingMode = SmoothingMode.HighQuality;
                Brush brush = new TextureBrush(StartImage);
                GraphicsPath gp = new GraphicsPath();
                gp.AddArc(0, 0, CornerRadius, CornerRadius, 180, 90);
                gp.AddArc(0 + RoundedImage.Width - CornerRadius, 0, CornerRadius, CornerRadius, 270, 90);
                gp.AddArc(0 + RoundedImage.Width - CornerRadius, 0 + RoundedImage.Height - CornerRadius, CornerRadius, CornerRadius, 0, 90);
                gp.AddArc(0, 0 + RoundedImage.Height - CornerRadius, CornerRadius, CornerRadius, 90, 90);
                g.FillPath(brush, gp);
                return RoundedImage;
            }
        }

        public static void DrawRoundedRectangle(Graphics graphics, Pen pen, Rectangle bounds, int cornerRadius)
        {
            if (graphics == null)
                throw new ArgumentNullException("graphics");
            if (pen == null)
                throw new ArgumentNullException("pen");

            using (GraphicsPath path = RoundedRect(bounds, cornerRadius))
            {
                graphics.DrawPath(pen, path);
            }
        }

        public static void FillRoundedRectangle(Graphics graphics, Brush brush, Rectangle bounds, int cornerRadius)
        {
            if (graphics == null)
                throw new ArgumentNullException("graphics");
            if (brush == null)
                throw new ArgumentNullException("brush");

            using (GraphicsPath path = RoundedRect(bounds, cornerRadius))
            {
                graphics.FillPath(brush, path);
            }
        }

        public static GraphicsPath RoundedRect(Rectangle bounds, int radius)
        {
            int diameter = radius * 2;
            Size size = new Size(diameter, diameter);
            Rectangle arc = new Rectangle(bounds.Location, size);
            GraphicsPath path = new GraphicsPath();

            if (radius == 0)
            {
                path.AddRectangle(bounds);
                return path;
            }

            // top left arc  
            path.AddArc(arc, 180, 90);

            // top right arc  
            arc.X = bounds.Right - diameter;
            path.AddArc(arc, 270, 90);

            // bottom right arc  
            arc.Y = bounds.Bottom - diameter;
            path.AddArc(arc, 0, 90);

            // bottom left arc 
            arc.X = bounds.Left;
            path.AddArc(arc, 90, 90);

            path.CloseFigure();
            return path;
        }

        public static Image MakeGrayscale(Image original)
        {
            //create a blank bitmap the same size as original
            Image newBitmap = new Bitmap(original.Width, original.Height);

            //get a graphics object from the new image
            using (Graphics g = Graphics.FromImage(newBitmap))
            {

                //create the grayscale ColorMatrix
                ColorMatrix colorMatrix = new ColorMatrix(
                   new float[][]
                   {
             new float[] {.3f, .3f, .3f, 0, 0},
             new float[] {.59f, .59f, .59f, 0, 0},
             new float[] {.11f, .11f, .11f, 0, 0},
             new float[] {0, 0, 0, 1, 0},
             new float[] {0, 0, 0, 0, 1}
                   });

                //create some image attributes
                using (ImageAttributes attributes = new ImageAttributes())
                {

                    //set the color matrix attribute
                    attributes.SetColorMatrix(colorMatrix);

                    //draw the original image on the new image
                    //using the grayscale color matrix
                    g.DrawImage(original, new Rectangle(0, 0, original.Width, original.Height),
                                0, 0, original.Width, original.Height, GraphicsUnit.Pixel, attributes);
                }
            }
            return newBitmap;
        }
    }
}