Run the SpatialFilterCommandBitmapEffect on an image and apply a Prewitt edge detection filter.

Visual Basic

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Public Sub SpatialFilterCommandBitmapEffectExample(ByVal element As FrameworkElement)    Dim effect As SpatialFilterCommandBitmapEffect = New SpatialFilterCommandBitmapEffect()    effect.Divisor = 1    effect.Bias = 0    effect.Matrix = New Integer() {-1, -1, -1, -1, 8, -1, -1, -1, -1}    element.BitmapEffect = effect    Dim storyboard As Storyboard = New Storyboard()    Dim animation1 As Int32Animation = New Int32Animation()    animation1.From = 1    animation1.To = 16    animation1.Duration = New Duration(TimeSpan.Parse("0:0:2"))    animation1.RepeatBehavior = RepeatBehavior.Forever    animation1.AutoReverse = True    storyboard.SetTargetName(animation1, "AnimatedBitmapEffect")    storyboard.SetTargetProperty(animation1, New PropertyPath(SpatialFilterCommandBitmapEffect.BiasProperty))    element.RegisterName("AnimatedBitmapEffect", effect)    storyboard.Children.Add(animation1)    Dim animation2 As Int32Animation = New Int32Animation()    animation2.From = 2    animation2.To = 32    animation2.Duration = New Duration(TimeSpan.Parse("0:0:2"))    animation2.RepeatBehavior = RepeatBehavior.Forever    animation2.AutoReverse = True    storyboard.SetTargetName(animation2, "AnimatedBitmapEffect")    storyboard.SetTargetProperty(animation2, New PropertyPath(SpatialFilterCommandBitmapEffect.DivisorProperty))    element.RegisterName("AnimatedBitmapEffect", effect)    storyboard.Children.Add(animation2)    storyboard.Begin(element) End Sub

C#

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public void SpatialFilterCommandBitmapEffectExample(FrameworkElement element)  {     SpatialFilterCommandBitmapEffect effect = new SpatialFilterCommandBitmapEffect();     effect.Divisor = 1;     effect.Bias = 0;     effect.Matrix = new int[] { -1, -1, -1, -1, 8, -1, -1, -1, -1 };     element.BitmapEffect = effect;       Storyboard storyboard = new Storyboard();       Int32Animation animation1 = new Int32Animation();     animation1.From = 1;     animation1.To = 16;     animation1.Duration = new Duration(TimeSpan.Parse("0:0:2"));     animation1.RepeatBehavior = RepeatBehavior.Forever;     animation1.AutoReverse = true;       Storyboard.SetTargetName(animation1, "AnimatedBitmapEffect");     Storyboard.SetTargetProperty(animation1, new PropertyPath(SpatialFilterCommandBitmapEffect.BiasProperty));     element.RegisterName("AnimatedBitmapEffect", effect);     storyboard.Children.Add(animation1);       Int32Animation animation2 = new Int32Animation();     animation2.From = 2;     animation2.To = 32;     animation2.Duration = new Duration(TimeSpan.Parse("0:0:2"));     animation2.RepeatBehavior = RepeatBehavior.Forever;     animation2.AutoReverse = true;       Storyboard.SetTargetName(animation2, "AnimatedBitmapEffect");     Storyboard.SetTargetProperty(animation2, new PropertyPath(SpatialFilterCommandBitmapEffect.DivisorProperty));     element.RegisterName("AnimatedBitmapEffect", effect);     storyboard.Children.Add(animation2);       storyboard.Begin(element);  }

XAML

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<!-- Broken.  Not sure on this yet. -->  <Page Title="CSAnimateEffect" Height="391" Width="300" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:lteffects="clr-namespace:Leadtools.Windows.Media.Effects.Effects;assembly=Leadtools.Windows.Media.Effects">    <Grid>      <Image Margin="10,10,10,10" HorizontalAlignment="Center" VerticalAlignment="Center" Source="C:\Program Files\LEAD Technologies, Inc\LEADTOOLS 16\Images\slave.jpg">        <Image.BitmapEffect>          <lteffects:SpatialFilterCommandBitmapEffect x:Name="AnimatedBitmapEffect" />        </Image.BitmapEffect>        <Image.Triggers>          <EventTrigger RoutedEvent="Image.Loaded">            <BeginStoryboard>              <Storyboard>                <Int32Animation Storyboard.TargetName="AnimatedBitmapEffect" Storyboard.TargetProperty="Bias" From="0" To="255" Duration="0:0:5" RepeatBehavior="Forever" AutoReverse="true" />                <Int32Animation Storyboard.TargetName="AnimatedBitmapEffect" Storyboard.TargetProperty="Divisor" From="1" To="255" Duration="0:0:5" RepeatBehavior="Forever" AutoReverse="true" />              </Storyboard>            </BeginStoryboard>          </EventTrigger>        </Image.Triggers>      </Image>    </Grid>  </Page>

• A spatial filter recomputes the brightness of each pixel in an image by using a weighted averaging technique that considers the surrounding pixels. Spatial filters are used for operations such as sharpening an image or detecting edges within the image.
• The SpatialFilterCommandBitmapEffect works best with 24-bit, 16-bit, or grayscale images. If the image uses a color palette, this command matches the new brightness value of each pixel to the nearest color in the existing palette.
• It is beyond the scope of this documentation to explain how applying various weighting factors affects an image. For such information, refer to a textbook on image processing like Digital Image Processing: Principles and Applications, by Gregory A. Baxes.

System.Object
   System.Windows.Threading.DispatcherObject
      System.Windows.DependencyObject
         System.Windows.Freezable
            System.Windows.Media.Animation.Animatable
               System.Windows.Media.Effects.BitmapEffect
                  Leadtools.Windows.Media.Effects.RasterCommandBitmapEffect
                     Leadtools.Windows.Media.Effects.Effects.SpatialFilterCommandBitmapEffect

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Vista, Windows Server 2003 family, Windows Server 2008 family

Reference