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BitmapSource Class

Definition

Represents a single, constant set of pixels at a certain size and resolution.

public ref class BitmapSource abstract : System::Windows::Media::ImageSource
[System.Windows.Localizability(System.Windows.LocalizationCategory.None, Readability=System.Windows.Readability.Unreadable)]
public abstract class BitmapSource : System.Windows.Media.ImageSource
[<System.Windows.Localizability(System.Windows.LocalizationCategory.None, Readability=System.Windows.Readability.Unreadable)>]
type BitmapSource = class
    inherit ImageSource
    interface DUCE.IResource
[<System.Windows.Localizability(System.Windows.LocalizationCategory.None, Readability=System.Windows.Readability.Unreadable)>]
type BitmapSource = class
    inherit ImageSource
Public MustInherit Class BitmapSource
Inherits ImageSource
Inheritance
Derived
Attributes

Examples

The following code example demonstrates how to create a BitmapSource and use it as the source of an Image control.

// Define parameters used to create the BitmapSource.
PixelFormat pf = PixelFormats.Bgr32;
int width = 200;
int height = 200;
int rawStride = (width * pf.BitsPerPixel + 7) / 8;
byte[] rawImage = new byte[rawStride * height];

// Initialize the image with data.
Random value = new Random();
value.NextBytes(rawImage);

// Create a BitmapSource.
BitmapSource bitmap = BitmapSource.Create(width, height,
    96, 96, pf, null,
    rawImage, rawStride);

// Create an image element;
Image myImage = new Image();
myImage.Width = 200;
// Set image source.
myImage.Source = bitmap;
' Define parameters used to create the BitmapSource.
Dim pf As PixelFormat = PixelFormats.Bgr32
Dim width As Integer = 200
Dim height As Integer = 200
Dim rawStride As Integer = CType((width * pf.BitsPerPixel + 7) / 8, Integer)
Dim rawImage(rawStride * height) As Byte

' Initialize the image with data.
Dim value As New Random()
value.NextBytes(rawImage)

' Create a BitmapSource.
Dim bitmap As BitmapSource = BitmapSource.Create(width, height, 96, 96, pf, Nothing, rawImage, rawStride)

' Create an image element;
Dim myImage As New Image()
myImage.Width = 200
' Set image source.
myImage.Source = bitmap

The following code example uses a BitmapSource derived class, BitmapImage, to create a bitmap from an image file and use it as the source of an Image control.

// Create the image element.
Image simpleImage = new Image();    
simpleImage.Width = 200;
simpleImage.Margin = new Thickness(5);

// Create source.
BitmapImage bi = new BitmapImage();
// BitmapImage.UriSource must be in a BeginInit/EndInit block.
bi.BeginInit();
bi.UriSource = new Uri(@"/sampleImages/cherries_larger.jpg",UriKind.RelativeOrAbsolute);
bi.EndInit();
// Set the image source.
simpleImage.Source = bi;
' Create the image element.
Dim simpleImage As New Image()
simpleImage.Width = 200
simpleImage.Margin = New Thickness(5)

' Create source.
Dim bi As New BitmapImage()
' BitmapImage.UriSource must be in a BeginInit/EndInit block.
bi.BeginInit()
bi.UriSource = New Uri("/sampleImages/cherries_larger.jpg", UriKind.RelativeOrAbsolute)
bi.EndInit()
' Set the image source.
simpleImage.Source = bi

Remarks

BitmapSource is the basic building block of the Windows Presentation Foundation (WPF) imaging pipeline, conceptually representing a single, constant set of pixels at a certain size and resolution. A BitmapSource could be a single frame in an image file that a decoder provides, or it could be the result of a transform that operates on a BitmapSource of its own. BitmapSource is not used to represent a multi-frame image or an animation.

Windows Presentation Foundation (WPF) natively supports compression and decompression of bitmap (BMP), Graphics Interchange Format (GIF), Joint Photographics Experts Group (JPEG), Portable Network Graphics (PNG), and Tagged Image File Format (TIFF) images.

For bitmap decoding scenarios, BitmapSource uses automatic codec discovery, based on the installed codecs on the user's system.

The maximum height and width of an image is 2^16 pixels at 32 bits per channel * 4 channels. The maximum size of a BitmapSource is 2^32 bytes (64 gigabytes) and the maximum image size is four gigapixels. The minimum image size is 1x1.

Constructors

BitmapSource()

Initializes a new instance of the BitmapSource class.

Properties

CanFreeze

Gets a value that indicates whether the object can be made unmodifiable.

(Inherited from Freezable)
DependencyObjectType

Gets the DependencyObjectType that wraps the CLR type of this instance.

(Inherited from DependencyObject)
Dispatcher

Gets the Dispatcher this DispatcherObject is associated with.

(Inherited from DispatcherObject)
DpiX

Gets the horizontal dots per inch (dpi) of the image.

DpiY

Gets the vertical dots per inch (dpi) of the image.

Format

Gets the native PixelFormat of the bitmap data.

HasAnimatedProperties

Gets a value that indicates whether one or more AnimationClock objects is associated with any of this object's dependency properties.

(Inherited from Animatable)
Height

Gets the height of the source bitmap in device-independent units (1/96th inch per unit).

IsDownloading

Gets a value that indicates whether the BitmapSource content is currently downloading.

IsFrozen

Gets a value that indicates whether the object is currently modifiable.

(Inherited from Freezable)
IsSealed

Gets a value that indicates whether this instance is currently sealed (read-only).

(Inherited from DependencyObject)
Metadata

Gets the metadata that is associated with this bitmap image.

Palette

Gets the color palette of the bitmap, if one is specified.

PixelHeight

Gets the height of the bitmap in pixels.

PixelWidth

Gets the width of the bitmap in pixels.

Width

Gets the width of the bitmap in device-independent units (1/96th inch per unit).

Methods

ApplyAnimationClock(DependencyProperty, AnimationClock, HandoffBehavior)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the specified HandoffBehavior is used.

(Inherited from Animatable)
ApplyAnimationClock(DependencyProperty, AnimationClock)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the SnapshotAndReplace handoff behavior is used.

(Inherited from Animatable)
BeginAnimation(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)
BeginAnimation(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)
CheckAccess()

Determines whether the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
CheckIfSiteOfOrigin()

Checks whether the bitmap source content is from a known site of origin. This method is used to make sure that pixel copying operations are safe.

ClearValue(DependencyProperty)

Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier.

(Inherited from DependencyObject)
ClearValue(DependencyPropertyKey)

Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey.

(Inherited from DependencyObject)
Clone()

Creates a modifiable clone of this BitmapSource, 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.

CloneCore(Freezable)

Makes this instance a deep copy of the specified BitmapSource. 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.

CloneCurrentValue()

Creates a modifiable clone of this BitmapSource object, making deep copies of this object's current values. Resource references, data bindings, and animations are not copied, but their current values are.

CloneCurrentValueCore(Freezable)

Makes this instance a modifiable deep copy of the specified BitmapSource using current property values. Resource references, data bindings, and animations are not copied, but their current values are.

CoerceValue(DependencyProperty)

Coerces 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)
CopyPixels(Array, Int32, Int32)

Copies the bitmap pixel data into an array of pixels with the specified stride, starting at the specified offset.

CopyPixels(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.

CopyPixels(Int32Rect, IntPtr, Int32, Int32)

Copies the bitmap pixel data within the specified rectangle.

Create(Int32, Int32, Double, Double, PixelFormat, BitmapPalette, Array, Int32)

Creates a new BitmapSource from an array of pixels.

Create(Int32, Int32, Double, Double, PixelFormat, BitmapPalette, IntPtr, Int32, Int32)

Creates a new BitmapSource from an array of pixels that are stored in unmanaged memory.

CreateInstance()

Initializes a new instance of the Freezable class.

(Inherited from Freezable)
CreateInstanceCore()

When implemented in a derived class, creates a new instance of the Freezable derived class.

(Inherited from Freezable)
Equals(Object)

Determines whether a provided DependencyObject is equivalent to the current DependencyObject.

(Inherited from DependencyObject)
Freeze()

Makes the current object unmodifiable and sets its IsFrozen property to true.

(Inherited from Freezable)
FreezeCore(Boolean)

Makes an instance of BitmapSource or a derived class immutable.

GetAnimationBaseValue(DependencyProperty)

Returns the non-animated value of the specified DependencyProperty.

(Inherited from Animatable)
GetAsFrozen()

Creates 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)
GetAsFrozenCore(Freezable)

Makes this instance a clone of the specified BitmapSource object.

GetCurrentValueAsFrozen()

Creates 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)
GetCurrentValueAsFrozenCore(Freezable)

Makes this instance a frozen clone of the specified BitmapSource. Resource references, data bindings, and animations are not copied, but their current values are.

GetHashCode()

Gets a hash code for this DependencyObject.

(Inherited from DependencyObject)
GetLocalValueEnumerator()

Creates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject.

(Inherited from DependencyObject)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
GetValue(DependencyProperty)

Returns the current effective value of a dependency property on this instance of a DependencyObject.

(Inherited from DependencyObject)
InvalidateProperty(DependencyProperty)

Re-evaluates the effective value for the specified dependency property.

(Inherited from DependencyObject)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnChanged()

Called when the current Freezable object is modified.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject, DependencyProperty)

This member supports the Windows Presentation Foundation (WPF) infrastructure and is not intended to be used directly from your code.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject)

Ensures that appropriate context pointers are established for a DependencyObjectType data member that has just been set.

(Inherited from Freezable)
OnPropertyChanged(DependencyPropertyChangedEventArgs)

Overrides the DependencyObject implementation of OnPropertyChanged(DependencyPropertyChangedEventArgs) to also invoke any Changed handlers in response to a changing dependency property of type Freezable.

(Inherited from Freezable)
ReadLocalValue(DependencyProperty)

Returns the local value of a dependency property, if it exists.

(Inherited from DependencyObject)
ReadPreamble()

Ensures that the Freezable is being accessed from a valid thread. Inheritors of Freezable must call this method at the beginning of any API that reads data members that are not dependency properties.

(Inherited from Freezable)
SetCurrentValue(DependencyProperty, Object)

Sets the value of a dependency property without changing its value source.

(Inherited from DependencyObject)
SetValue(DependencyProperty, Object)

Sets the local value of a dependency property, specified by its dependency property identifier.

(Inherited from DependencyObject)
SetValue(DependencyPropertyKey, Object)

Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property.

(Inherited from DependencyObject)
ShouldSerializeProperty(DependencyProperty)

Returns a value that indicates whether serialization processes should serialize the value for the provided dependency property.

(Inherited from DependencyObject)
ToString()

Creates a string representation of this object based on the current culture.

(Inherited from ImageSource)
ToString(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)
VerifyAccess()

Enforces that the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
WritePostscript()

Raises the Changed event for the Freezable and invokes its OnChanged() method. Classes that derive from Freezable should call this method at the end of any API that modifies class members that are not stored as dependency properties.

(Inherited from Freezable)
WritePreamble()

Verifies that the Freezable is not frozen and that it is being accessed from a valid threading context. Freezable inheritors should call this method at the beginning of any API that writes to data members that are not dependency properties.

(Inherited from Freezable)

Events

Changed

Occurs when the Freezable or an object it contains is modified.

(Inherited from Freezable)
DecodeFailed

Occurs when the image fails to load, due to a corrupt image header.

DownloadCompleted

Occurs when the bitmap content has been completely downloaded.

DownloadFailed

Occurs when the bitmap content failed to download.

DownloadProgress

Occurs when the download progress of the bitmap content has changed.

Explicit Interface Implementations

IFormattable.ToString(String, IFormatProvider)

Formats the value of the current instance using the specified format.

(Inherited from ImageSource)

Applies to

See also