BitmapDecoder Class

BitmapDecoder Class


Represents a container for bitmap frames. Each bitmap frame is a BitmapSource. This abstract class provides a base set of functionality for all derived decoder objects.

Namespace:   System.Windows.Media.Imaging
Assembly:  PresentationCore (in PresentationCore.dll)

public abstract class BitmapDecoder : DispatcherObject


Initializes a new instance of BitmapDecoder.


Gets information that describes this . GTMT


Gets a value that represents the color profile associated with a , if one is defined.GTMT


Gets the Dispatcher this DispatcherObject is associated with. (Inherited from DispatcherObject.)


Gets the content of an individual frame within a .GTMT


Gets a value that indicates if the decoder is currently downloading content.


Gets an instance of BitmapMetadata that represents the global metadata associated with this bitmap, if metadata is defined.


Gets the BitmapPalette associated with this decoder.


Gets a BitmapSource that represents the global preview of this , if one is defined.GTMT


Gets a BitmapSource that represents the thumbnail of the bitmap, if one is defined.


Determines whether the calling thread has access to this DispatcherObject.(Inherited from DispatcherObject.)

System_CAPS_pubmethodSystem_CAPS_staticCreate(Stream, BitmapCreateOptions, BitmapCacheOption)

Creates a BitmapDecoder from a Stream by using the specified BitmapCreateOptions and BitmapCacheOption.

System_CAPS_pubmethodSystem_CAPS_staticCreate(Uri, BitmapCreateOptions, BitmapCacheOption)

Creates a BitmapDecoder from a Uri by using the specified BitmapCreateOptions and BitmapCacheOption.

System_CAPS_pubmethodSystem_CAPS_staticCreate(Uri, BitmapCreateOptions, BitmapCacheOption, RequestCachePolicy)

Creates a BitmapDecoder from a Uri by using the specified BitmapCreateOptions, BitmapCacheOption and RequestCachePolicy.



Determines whether the specified object is equal to the current object.(Inherited from Object.)


Frees resources and performs other cleanup operations before the BitmapDecoder is reclaimed by garbage collection. (Overrides Object.Finalize().)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Creates a shallow copy of the current Object.(Inherited from Object.)


Converts the current value of a BitmapDecoder to a String.(Overrides Object.ToString().)


Enforces that the calling thread has access to this DispatcherObject.(Inherited from DispatcherObject.)


Occurs when a BitmapDecoder has finished downloading content.GTMT


Occurs when content failed to download.GTMT


Occurs when a BitmapDecoder has made progress downloading content.GTMT

BitmapDecoder is not a BitmapFrame itself; rather, it is a container for BitmapFrame objects. Each BitmapFrame in the container can potentially have different attributes, including different sizes, resolutions, or palettes.

Unless a specific codec is selected, Windows Presentation Foundation (WPF) uses automatic run-time discovery to identify the format of an image and match it with the appropriate codec. This discovery process allows a codec developed by an independent software vendor (ISV) to be automatically discoverable by the system. To select a specific codec, the derived BitmapDecoder or BitmapEncoder, such as the TiffBitmapDecoder class, should be used.

Tagged Image File Format (TIFF) and Graphics Interchange Format (GIF) are the only implemented image formats that support multiple frames.

The following example demonstrates how to use the Create(Uri, BitmapCreateOptions, BitmapCacheOption) method to create a decoder for a given image. The first BitmapFrame of the image is used as the source of an Image control.

Dim uriBitmap As BitmapDecoder = BitmapDecoder.Create(New Uri("sampleImages/waterlilies.jpg", UriKind.Relative), BitmapCreateOptions.None, BitmapCacheOption.Default)

' Create an image element;
Dim uriImage As New Image()
uriImage.Width = 200
' Set image source.
uriImage.Source = uriBitmap.Frames(0)

The following code example demonstrates how to use the built in TiffBitmapDecoder to open and decode a Tagged Image File Format (TIFF) bitmap. The resulting BitmapSource is used as the Source of an Image element.

' Open a Stream and decode a TIFF image
Dim imageStreamSource As New FileStream("tulipfarm.tif", FileMode.Open, FileAccess.Read, FileShare.Read)
Dim decoder As New TiffBitmapDecoder(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default)
Dim bitmapSource As BitmapSource = decoder.Frames(0)

' Draw the Image
Dim myImage1 As New Image()
myImage1.Source = bitmapSource
myImage1.Stretch = Stretch.None
myImage1.Margin = New Thickness(20)

.NET Framework
Available since 3.0

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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