Run the HistogramContrastCommandBitmapEffect on an image and increase its contrast.

Visual Basic

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Public Sub HistogramContrastCommandBitmapEffectExample(ByVal element As FrameworkElement)    ' Initialize Effect    Dim effect As HistogramContrastCommandBitmapEffect = New HistogramContrastCommandBitmapEffect()    effect.Contrast = 250    element.BitmapEffect = effect    ' Initialize Animations    Dim animation1 As Int32Animation = New Int32Animation()    animation1.From = -1000    animation1.To = 1000    animation1.By = 1    animation1.Duration = New Duration(TimeSpan.FromSeconds(2.0))    animation1.AutoReverse = True    animation1.RepeatBehavior = RepeatBehavior.Forever    ' Initialize and run Storyboard    Dim storyboard As Storyboard = New Storyboard()    storyboard.SetTargetName(animation1, "AnimatedBitmapEffect")    storyboard.SetTargetProperty(animation1, New PropertyPath(HistogramContrastCommandBitmapEffect.ContrastProperty))    element.RegisterName("AnimatedBitmapEffect", effect)    storyboard.Children.Add(animation1)    storyboard.Begin(element) End Sub

C#

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public void HistogramContrastCommandBitmapEffectExample(FrameworkElement element)  {     // Initialize Effect     HistogramContrastCommandBitmapEffect effect = new HistogramContrastCommandBitmapEffect();     effect.Contrast = 250;     element.BitmapEffect = effect;       // Initialize Animations     Int32Animation animation1 = new Int32Animation();     animation1.From = -1000;     animation1.To = 1000;     animation1.By = 1;     animation1.Duration = new Duration(TimeSpan.FromSeconds(2.0));     animation1.AutoReverse = true;     animation1.RepeatBehavior = RepeatBehavior.Forever;       // Initialize and run Storyboard     Storyboard storyboard = new Storyboard();     Storyboard.SetTargetName(animation1, "AnimatedBitmapEffect");     Storyboard.SetTargetProperty(animation1, new PropertyPath(HistogramContrastCommandBitmapEffect.ContrastProperty));     element.RegisterName("AnimatedBitmapEffect", effect);     storyboard.Children.Add(animation1);       storyboard.Begin(element);  }

XAML

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<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.Color;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:HistogramContrastCommandBitmapEffect x:Name="MyBitmapEffect" />        </Image.BitmapEffect>        <Image.Triggers>          <EventTrigger RoutedEvent="Image.Loaded">            <BeginStoryboard>              <Storyboard>                <Int32Animation Storyboard.TargetName="MyBitmapEffect" Storyboard.TargetProperty="Contrast" From="-1000" To="1000" Duration="0:0:2" RepeatBehavior="Forever" AutoReverse="True" />              </Storyboard>            </BeginStoryboard>          </EventTrigger>        </Image.Triggers>      </Image>    </Grid>  </Page>

• This class finds the median brightness of the image, then brightens the pixels with values above the median and darkens the pixels with values below the median. This is more sophisticated (but slower) than the ChangeContrastCommandBitmapEffect, which uses the middle possible value (128) rather than finding the actual median.

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.Color.HistogramContrastCommandBitmapEffect

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

Reference