C#

public static Image SetImgOpacity(Image imgPic, float imgOpac)
{  
   Bitmap bmpPic = new Bitmap(imgPic.Width, imgPic.Height);
   Graphics gfxPic = Graphics.FromImage(bmpPic);
   ColorMatrix cmxPic = new ColorMatrix();
            
   cmxPic.Matrix33 = imgOpac;
            
   ImageAttributes iaPic = new ImageAttributes();
   iaPic.SetColorMatrix(cmxPic, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
   gfxPic.DrawImage(imgPic, new Rectangle(0, 0, bmpPic.Width, bmpPic.Height), 0, 0, imgPic.Width, imgPic.Height, GraphicsUnit.Pixel, iaPic);
   gfxPic.Dispose();
  
   return bmpPic;
}

using (Image img = Image.FromFile(filename))
{
   Image img2 = ((Bitmap)img).Clone(new Rectangle(0, 0, img.Width, img.Height), PixelFormat.Format32bppArgb);
   img2 = SetImgOpacity(img2, 0.5f);
   img2.Save(filename2, ImageFormat.Png);
   img2.Dispose();
}

cmxPic.Matrix00 = 0.299f;
cmxPic.Matrix01 = 0.299f;
cmxPic.Matrix02 = 0.299f;

cmxPic.Matrix10 = 0.587f;
cmxPic.Matrix11 = 0.587f;
cmxPic.Matrix12 = 0.587f;

cmxPic.Matrix20 = 0.114f;
cmxPic.Matrix21 = 0.114f;
cmxPic.Matrix22 = 0.114f;

Sajjad Izadi wrote:

i have an image and i want to make it white and black. how can i do that?

SpellCheck checker = new SpellCheck();
            PhoenixText.Forms.MdiWindow win = (PhoenixText.Forms.MdiWindow)this.ActiveMdiChild;
            Char[] characters = win.TextBox.Text.ToCharArray();
            foreach (string word in win.KeyWords)
            {
                int firstIndex = win.TextBox.Text.IndexOf(word);
                int lastindex = word.Length;
               // MessageBox.Show(firstIndex.ToString() + "   " + lastindex.ToString());
                if (checker.CheckSpelling(word) == false)
                {
                    win.TextBox.Select(firstIndex, lastindex);
                    win.TextBox.SelectionFont = new Font(win.TextBox.Font, FontStyle.Underline);
                    win.TextBox.DeselectAll();
                    win.TextBox.Refresh();
                }
            }