< UserControl x:Class ="WritableBitmapBnW.MainPage" 

     xmlns ="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 

     xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml" 

     xmlns:d ="http://schemas.microsoft.com/expression/blend/2008" 

     xmlns:mc ="http://schemas.openxmlformats.org/markup-compatibility/2006" 

     mc:Ignorable ="d" 

     d:DesignHeight ="200" d:DesignWidth ="500" > 

     < Grid x:Name ="LayoutRoot" Background ="White" > 

         < Image Height ="65" HorizontalAlignment ="Left" Margin ="69,76,0,0" Name ="imgSource" Stretch ="Fill" VerticalAlignment ="Top" Width ="137" Source ="bzspark.png" /> 

         < Button Content ="转黑白图" Height ="28" HorizontalAlignment ="Left" Margin ="217,113,0,0" Name ="btnConvertBnW" VerticalAlignment ="Top" Width ="76" FontSize ="14" FontFamily = "微软正黑体" Click ="btnConvertBnW_Click" /> 

         < Image Height ="65" HorizontalAlignment ="Left" Margin ="307,76,0,0" Name ="imgTarget" Stretch ="Fill" VerticalAlignment ="Top" Width ="137" /> 

     </ Grid > 

  </ UserControl > 

  private void btnConvertBnW_Click( object sender, RoutedEventArgs e) 

 { 

             //读入欲转换的图片并转成为WritableBitmap 

             WriteableBitmap bitmap = new WriteableBitmap( this .imgSource, null ); 

             for ( int y = 0; y < bitmap.PixelHeight; y++) 

             { 

                 for ( int x = 0; x < bitmap.PixelWidth; x++) 

                 { 

                     //取得每一个pixel 

                     int pixelLocation = bitmap.PixelWidth * y + x; 

                     int pixel = bitmap.Pixels[pixelLocation]; 

                     byte [] pixBytes = BitConverter.GetBytes(pixel); 

                     //每一个都除3 

                     byte bnwPixel = ( byte )(.333 * pixBytes[2] 

                                         + .333 * pixBytes[1] 

                                         + .333 * pixBytes[0]); 

                     pixBytes[0] = bnwPixel; //b 

                     pixBytes[1] = bnwPixel; //g 

                     pixBytes[2] = bnwPixel; //r 

                     //位置3是alpha 

                     //排列真是诡异阿..><刚好反过来s 

                     //将处理后的pixel置回 

                     bitmap.Pixels[pixelLocation] = BitConverter.ToInt32(pixBytes, 0); 

                 } 

             } 

             //显示结果 

             this .imgTarget.Source = bitmap; 

 }