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CroppedBitmap Class

Crops a BitmapSource.

Namespace:  System.Windows.Media.Imaging
Assembly:  PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation

public sealed class CroppedBitmap : BitmapSource, 
	ISupportInitialize
<CroppedBitmap .../>

The CroppedBitmap type exposes the following members.

  NameDescription
Public methodCroppedBitmap()Initializes a new instance of the CroppedBitmap class.
Public methodCroppedBitmap(BitmapSource, Int32Rect)Initializes a new instance of the CroppedBitmap class that has the specified Source and SourceRect.
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  NameDescription
Public propertyCanFreezeGets a value that indicates whether the object can be made unmodifiable. (Inherited from Freezable.)
Public propertyDependencyObjectTypeGets the DependencyObjectType that wraps the CLR type of this instance.  (Inherited from DependencyObject.)
Public propertyDispatcherGets the Dispatcher this DispatcherObject is associated with. (Inherited from DispatcherObject.)
Public propertyDpiXGets the horizontal dots per inch (dpi) of the image.  (Inherited from BitmapSource.)
Public propertyDpiYGets the vertical dots per inch (dpi) of the image.  (Inherited from BitmapSource.)
Public propertyFormatGets the native PixelFormat of the bitmap data. (Inherited from BitmapSource.)
Public propertyHasAnimatedPropertiesGets a value that indicates whether one or more AnimationClock objects is associated with any of this object's dependency properties. (Inherited from Animatable.)
Public propertyHeightGets the height of the source bitmap in device-independent units (1/96th inch per unit).  (Inherited from BitmapSource.)
Public propertyIsDownloadingGets a value that indicates whether the BitmapSource content is currently downloading. (Inherited from BitmapSource.)
Public propertyIsFrozenGets a value that indicates whether the object is currently modifiable. (Inherited from Freezable.)
Public propertyIsSealedGets a value that indicates whether this instance is currently sealed (read-only). (Inherited from DependencyObject.)
Public propertyMetadataGets the metadata that is associated with this bitmap image. (Inherited from BitmapSource.)
Public propertyPaletteGets the color palette of the bitmap, if one is specified. (Inherited from BitmapSource.)
Public propertyPixelHeightGets the height of the bitmap in pixels. (Inherited from BitmapSource.)
Public propertyPixelWidthGets the width of the bitmap in pixels. (Inherited from BitmapSource.)
Public propertySourceGets or sets the source for the bitmap.
Public propertySourceRectGets or sets the rectangular area that the bitmap is cropped to.
Public propertyWidthGets the width of the bitmap in device-independent units (1/96th inch per unit).  (Inherited from BitmapSource.)
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  NameDescription
Public methodApplyAnimationClock(DependencyProperty, AnimationClock)Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the SnapshotAndReplace handoff behavior is used. (Inherited from Animatable.)
Public methodApplyAnimationClock(DependencyProperty, AnimationClock, HandoffBehavior)Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the specified HandoffBehavior is used. (Inherited from Animatable.)
Public methodBeginAnimation(DependencyProperty, AnimationTimeline)Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the SnapshotAndReplace handoff behavior is used. (Inherited from Animatable.)
Public methodBeginAnimation(DependencyProperty, AnimationTimeline, HandoffBehavior)Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the specified HandoffBehavior is used. (Inherited from Animatable.)
Public methodBeginInitSignals the start of the CroppedBitmap initialization.
Public methodCheckAccessDetermines whether the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
Public methodClearValue(DependencyProperty)Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier. (Inherited from DependencyObject.)
Public methodClearValue(DependencyPropertyKey)Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey. (Inherited from DependencyObject.)
Public methodCloneCreates a modifiable clone of this CroppedBitmap, making deep copies of this object's values. When copying dependency properties, this method copies resource references and data bindings (but they might no longer resolve) but not animations or their current values.
Public methodCloneCurrentValueCreates a modifiable clone of this CroppedBitmap object, making deep copies of this object's current values. Resource references, data bindings, and animations are not copied, but their current values are.
Public methodCoerceValueCoerces the value of the specified dependency property. This is accomplished by invoking any CoerceValueCallback function specified in property metadata for the dependency property as it exists on the calling DependencyObject. (Inherited from DependencyObject.)
Public methodCopyPixels(Array, Int32, Int32)Copies the bitmap pixel data into an array of pixels with the specified stride, starting at the specified offset. (Inherited from BitmapSource.)
Public methodCopyPixels(Int32Rect, Array, Int32, Int32)Copies the bitmap pixel data within the specified rectangle into an array of pixels that has the specified stride starting at the specified offset. (Inherited from BitmapSource.)
Public methodCopyPixels(Int32Rect, IntPtr, Int32, Int32)Copies the bitmap pixel data within the specified rectangle (Inherited from BitmapSource.)
Public methodEndInitSignals the end of the CroppedBitmap initialization.
Public methodEqualsDetermines whether a provided DependencyObject is equivalent to the current DependencyObject. (Inherited from DependencyObject.)
Public methodFreeze()Makes the current object unmodifiable and sets its IsFrozen property to true. (Inherited from Freezable.)
Public methodGetAnimationBaseValueReturns the non-animated value of the specified DependencyProperty. (Inherited from Animatable.)
Public methodGetAsFrozenCreates a frozen copy of the Freezable, using base (non-animated) property values. Because the copy is frozen, any frozen sub-objects are copied by reference. (Inherited from Freezable.)
Public methodGetCurrentValueAsFrozenCreates a frozen copy of the Freezable using current property values. Because the copy is frozen, any frozen sub-objects are copied by reference. (Inherited from Freezable.)
Public methodGetHashCodeGets a hash code for this DependencyObject. (Inherited from DependencyObject.)
Public methodGetLocalValueEnumeratorCreates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject. (Inherited from DependencyObject.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodGetValueReturns the current effective value of a dependency property on this instance of a DependencyObject. (Inherited from DependencyObject.)
Public methodInvalidatePropertyRe-evaluates the effective value for the specified dependency property (Inherited from DependencyObject.)
Public methodReadLocalValueReturns the local value of a dependency property, if it exists. (Inherited from DependencyObject.)
Public methodSetCurrentValueSets the value of a dependency property without changing its value source. (Inherited from DependencyObject.)
Public methodSetValue(DependencyProperty, Object)Sets the local value of a dependency property, specified by its dependency property identifier. (Inherited from DependencyObject.)
Public methodSetValue(DependencyPropertyKey, Object)Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property. (Inherited from DependencyObject.)
Protected methodShouldSerializePropertyReturns a value that indicates whether serialization processes should serialize the value for the provided dependency property. (Inherited from DependencyObject.)
Public methodToString() Creates a string representation of this object based on the current culture. (Inherited from ImageSource.)
Public methodToString(IFormatProvider)Creates a string representation of this object based on the IFormatProvider passed in. If the provider is null, the CurrentCulture is used. (Inherited from ImageSource.)
Public methodVerifyAccessEnforces that the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
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  NameDescription
Public eventChangedOccurs when the Freezable or an object it contains is modified. (Inherited from Freezable.)
Public eventDecodeFailedOccurs when the image fails to load, due to a corrupt image header. (Inherited from BitmapSource.)
Public eventDownloadCompletedOccurs when the bitmap content has been completely downloaded. (Inherited from BitmapSource.)
Public eventDownloadFailedOccurs when the bitmap content failed to download. (Inherited from BitmapSource.)
Public eventDownloadProgressOccurs when the download progress of the bitmap content has changed. (Inherited from BitmapSource.)
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  NameDescription
Public fieldStatic memberSourcePropertyIdentifies the Source dependency property.
Public fieldStatic memberSourceRectPropertyIdentifies the SourceRect dependency property.
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  NameDescription
Explicit interface implemetationPrivate methodIFormattable.ToStringFormats the value of the current instance using the specified format. (Inherited from ImageSource.)
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CroppedBitmap implements the ISupportInitialize interface to optimize initialization on multiple properties. Property changes can occur only during object initialization. Call BeginInit to signal that initialization has begun and EndInit to signal that initialization has completed. After initialization, property changes are ignored.

CroppedBitmap objects created by using the CroppedBitmap(BitmapSource, Int32Rect) constructor are automatically initialized, and properties cannot be changed.

Metadata tags related to image data must be updated if an image is saved to a file after a transform is applied.

Use the SourceRect property of this class to define the area of the bitmap that is to be cropped.

This example shows how to crop an image using CroppedBitmap.

CroppedBitmap is primarily used when encoding a cropped version of an image to save out to a file. To crop an image for display purposes see the How to: Create a Clip Region topic.

The following Extensible Application Markup Language (XAML) defines resources used within the samples below.

<Page.Resources>
   <!-- Define some image resources, for use as the image element source. -->
   <BitmapImage x:Key="masterImage" UriSource="/sampleImages/gecko.jpg" />
   <CroppedBitmap x:Key="croppedImage" 
      Source="{StaticResource masterImage}" SourceRect="30 20 105 50"/>
</Page.Resources>

The following example creates an image using a CroppedBitmap as its source.

<!-- Use the cropped image resource as the images source -->
<Image Width="200" Source="{StaticResource croppedImage}" 
   Margin="5" Grid.Column="0" Grid.Row="1" />
// Create an Image element.
Image croppedImage = new Image();
croppedImage.Width = 200;
croppedImage.Margin = new Thickness(5);

// Create a CroppedBitmap based off of a xaml defined resource.
CroppedBitmap cb = new CroppedBitmap(     
   (BitmapSource)this.Resources["masterImage"],
   new Int32Rect(30, 20, 105, 50));       //select region rect
croppedImage.Source = cb;                 //set image source to cropped

The CroppedBitmap can also be used as the source of another CroppedBitmap, chaining the cropping. Note that the SourceRect uses values that are relative to the source cropped bitmap and not the initial image.

<!-- Chain a cropped bitmap off a previosly defined cropped image -->
<Image Width="200" Grid.Column="0" Grid.Row="3" Margin="5">
   <Image.Source>
      <CroppedBitmap Source="{StaticResource croppedImage}" 
         SourceRect="30 0 75 50"/>
   </Image.Source>
</Image>
// Create an Image element.
Image chainImage = new Image();
chainImage.Width = 200;
chainImage.Margin = new Thickness(5);

// Create the cropped image based on previous CroppedBitmap.
CroppedBitmap chained = new CroppedBitmap(cb,
   new Int32Rect(30, 0, (int)cb.Width-30, (int)cb.Height)); 
// Set the image's source.
chainImage.Source = chained;

More Code

How to: Chain BitmapSource Objects TogetherThis example shows how you can apply a variety of effects to an image source by chaining multiple BitmapSource derived objects together.

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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