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BitmapFrame Class

Definition

Represents image data returned by a decoder and accepted by encoders.

public ref class BitmapFrame abstract : System::Windows::Media::Imaging::BitmapSource, System::Windows::Markup::IUriContext
public abstract class BitmapFrame : System.Windows.Media.Imaging.BitmapSource, System.Windows.Markup.IUriContext
type BitmapFrame = class
    inherit BitmapSource
    interface IUriContext
Public MustInherit Class BitmapFrame
Inherits BitmapSource
Implements IUriContext
Inheritance
Implements

Examples

The following code example demonstrates how to create a new BitmapSource by using a BitmapFrame.

int width = 128;
int height = width;
int stride = width/8;
byte[] pixels = new byte[height*stride];

// Try creating a new image with a custom palette.
List<System.Windows.Media.Color> colors = new List<System.Windows.Media.Color>();
colors.Add(System.Windows.Media.Colors.Red);
colors.Add(System.Windows.Media.Colors.Blue);
colors.Add(System.Windows.Media.Colors.Green);
BitmapPalette myPalette = new BitmapPalette(colors);

// Creates a new empty image with the pre-defined palette

BitmapSource image = BitmapSource.Create(
    width,
    height,
    96,
    96,
    PixelFormats.Indexed1,
    myPalette, 
    pixels, 
    stride);

FileStream stream = new FileStream("empty.tif", FileMode.Create);
TiffBitmapEncoder encoder = new TiffBitmapEncoder();
TextBlock myTextBlock = new TextBlock();
myTextBlock.Text = "Codec Author is: " + encoder.CodecInfo.Author.ToString();
encoder.Frames.Add(BitmapFrame.Create(image));
MessageBox.Show(myPalette.Colors.Count.ToString());
encoder.Save(stream);
Dim width As Integer = 128
Dim height As Integer = width
Dim stride As Integer = CType(width / 8, Integer)
Dim pixels(height * stride) As Byte

' Try creating a new image with a custom palette.
Dim colors As New List(Of System.Windows.Media.Color)()
colors.Add(System.Windows.Media.Colors.Red)
colors.Add(System.Windows.Media.Colors.Blue)
colors.Add(System.Windows.Media.Colors.Green)
Dim myPalette As New BitmapPalette(colors)

' Creates a new empty image with the pre-defined palette
Dim image As BitmapSource = System.Windows.Media.Imaging.BitmapSource.Create(width, height, 96, 96, PixelFormats.Indexed1, myPalette, pixels, stride)
Dim stream As New FileStream("empty.tif", FileMode.Create)
Dim encoder As New TiffBitmapEncoder()
Dim myTextBlock As New TextBlock()
myTextBlock.Text = "Codec Author is: " + encoder.CodecInfo.Author.ToString()
encoder.Frames.Add(BitmapFrame.Create(image))
MessageBox.Show(myPalette.Colors.Count.ToString())
encoder.Save(stream)

The following code example demonstrates how to use the BitmapFrame object to open a Portable Network Graphics (PNG) graphic and write metadata by using the CreateInPlaceBitmapMetadataWriter method.

Stream^ pngStream = gcnew FileStream("smiley.png", FileMode::Open, FileAccess::ReadWrite, FileShare::ReadWrite);
PngBitmapDecoder^ pngDecoder = gcnew PngBitmapDecoder(pngStream, BitmapCreateOptions::PreservePixelFormat, BitmapCacheOption::Default);
BitmapFrame^ pngFrame = pngDecoder->Frames[0];
InPlaceBitmapMetadataWriter^ pngInplace = pngFrame->CreateInPlaceBitmapMetadataWriter();
if (pngInplace->TrySave() == true)
{
   pngInplace->SetQuery("/Text/Description", "Have a nice day.");
}
pngStream->Close();
Stream pngStream = new System.IO.FileStream("smiley.png", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
PngBitmapDecoder pngDecoder = new PngBitmapDecoder(pngStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
BitmapFrame pngFrame = pngDecoder.Frames[0];
InPlaceBitmapMetadataWriter pngInplace = pngFrame.CreateInPlaceBitmapMetadataWriter();
if (pngInplace.TrySave() == true)
{ pngInplace.SetQuery("/Text/Description", "Have a nice day."); }
pngStream.Close();
Dim pngStream As New System.IO.FileStream("smiley.png", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite)
Dim pngDecoder As New PngBitmapDecoder(pngStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default)
Dim pngFrame As BitmapFrame = pngDecoder.Frames(0)
Dim pngInplace As InPlaceBitmapMetadataWriter = pngFrame.CreateInPlaceBitmapMetadataWriter()
If pngInplace.TrySave() = True Then
    pngInplace.SetQuery("/Text/Description", "Have a nice day.")
End If
pngStream.Close()

Remarks

BitmapFrame provides additional functionality not defined by BitmapSource by providing access to the Thumbnail associated with a particular frame of an image. BitmapFrame also supports the writing of metadata information by using the Metadata property or the CreateInPlaceBitmapMetadataWriter method.

Any BitmapFrame returned from a decoder is always frozen. If you require a modifiable copy, you must first create a copy of the BitmapFrame by using the Clone method.

Only Tagged Image File Format (TIFF) and Graphics Interchange Format (GIF) format images support multiple frames.

Constructors

BitmapFrame()

Initializes a new instance of the BitmapFrame class.

Properties

BaseUri

When overridden in a derived class, gets or sets a value that represents the base Uri of the current context.

CanFreeze

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

(Inherited from Freezable)
ColorContexts

When overridden in a derived class, gets a collection of ColorContext objects that are associated with this BitmapFrame.

Decoder

When overridden in a derived class, gets the decoder associated with this instance of BitmapFrame.

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.

(Inherited from BitmapSource)
DpiY

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

(Inherited from BitmapSource)
Format

Gets the native PixelFormat of the bitmap data.

(Inherited from BitmapSource)
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).

(Inherited from BitmapSource)
IsDownloading

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

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
Palette

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

(Inherited from BitmapSource)
PixelHeight

Gets the height of the bitmap in pixels.

(Inherited from BitmapSource)
PixelWidth

Gets the width of the bitmap in pixels.

(Inherited from BitmapSource)
Thumbnail

When overridden in a derived class, gets the thumbnail image associated with this BitmapFrame.

Width

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

(Inherited from BitmapSource)

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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
CopyPixels(Int32Rect, IntPtr, Int32, Int32)

Copies the bitmap pixel data within the specified rectangle.

(Inherited from BitmapSource)
Create(BitmapSource, BitmapSource, BitmapMetadata, ReadOnlyCollection<ColorContext>)

Creates a new BitmapFrame from a given BitmapSource with the specified thumbnail, BitmapMetadata, and ColorContext.

Create(BitmapSource, BitmapSource)

Creates a new BitmapFrame from a given BitmapSource with the specified thumbnail.

Create(BitmapSource)

Creates a new BitmapFrame from a given BitmapSource.

Create(Stream, BitmapCreateOptions, BitmapCacheOption)

Creates a new BitmapFrame from a given Stream with the specified BitmapCreateOptions and BitmapCacheOption.

Create(Stream)

Creates a new BitmapFrame from a given Stream.

Create(Uri, BitmapCreateOptions, BitmapCacheOption, RequestCachePolicy)

Creates a BitmapFrame from a given Uri with the specified BitmapCreateOptions, BitmapCacheOption, and RequestCachePolicy.

Create(Uri, BitmapCreateOptions, BitmapCacheOption)

Creates a BitmapFrame from a given Uri with the specified BitmapCreateOptions and BitmapCacheOption.

Create(Uri, RequestCachePolicy)

Creates a BitmapFrame from a given Uri with the specified RequestCachePolicy.

Create(Uri)

Creates a new BitmapFrame from a given Uri.

CreateInPlaceBitmapMetadataWriter()

When overridden in a derived class, creates an instance of InPlaceBitmapMetadataWriter, which can be used to associate metadata with a BitmapFrame.

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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
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.

(Inherited from BitmapSource)
DownloadCompleted

Occurs when the bitmap content has been completely downloaded.

(Inherited from BitmapSource)
DownloadFailed

Occurs when the bitmap content failed to download.

(Inherited from BitmapSource)
DownloadProgress

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

(Inherited from BitmapSource)

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