wpf,图片灰化处理

 private BitmapSource ToGray(BitmapSource source)
{
 FormatConvertedBitmap re = new FormatConvertedBitmap();
 re.BeginInit();
 re.Source = source;
 re.DestinationFormat = PixelFormats.Gray8;
 re.EndInit();
 return re;
 }

　　

<Image HorizontalAlignment="Center" Width="30" Height="30" VerticalAlignment="Center" Stretch="None" Margin="0">
								<Image.Source>
									<FormatConvertedBitmap DestinationFormat="Gray8">
										<FormatConvertedBitmap.Source>
											<BitmapImage UriSource="/课本.png" />
										</FormatConvertedBitmap.Source>
									</FormatConvertedBitmap>
								</Image.Source>
								<Image.OpacityMask>
									<ImageBrush>
										<ImageBrush.ImageSource>
											<BitmapImage UriSource="/课本.png" />
										</ImageBrush.ImageSource>
									</ImageBrush>
								</Image.OpacityMask>
							</Image>

　　

xmlns:ee="http://schemas.microsoft.com/expression/2010/effects" 

        <Image Margin="0,0,0,49" Source="page2.png" Stretch="None">
            <Image.Effect>
                <ee:MonochromeEffect/>
            </Image.Effect>
        </Image>