Defines a decoder for Graphics Interchange Format (GIF) encoded images.
(in PresentationCore.dll)
Visual Basic (Declaration)
Public NotInheritable Class GifBitmapDecoder _
Inherits BitmapDecoder
Dim instance As GifBitmapDecoder
public sealed class GifBitmapDecoder : BitmapDecoder
public ref class GifBitmapDecoder sealed : public BitmapDecoder
public final class GifBitmapDecoder extends BitmapDecoder
You cannot directly create an instance of this class in XAML.
The following examples show how to decode and encode a Graphics Interchange Format (GIF) image using the specific GifBitmapDecoder and GifBitmapEncoder objects. For the complete sample, see GIF Encoder and Decoder Sample
This example demonstrates how to decode a GIF image using a GifBitmapDecoder from a FileStream.
' Open a Stream and decode a GIF image
Dim imageStreamSource As New FileStream("tulipfarm.gif", FileMode.Open, FileAccess.Read, FileShare.Read)
Dim decoder As New GifBitmapDecoder(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default)
Dim bitmapSource As BitmapSource = decoder.Frames(0)
' Draw the Image
Dim myImage As New Image()
myImage.Source = bitmapSource
myImage.Stretch = Stretch.None
myImage.Margin = New Thickness(20)
// Open a Stream and decode a GIF image
Stream imageStreamSource = new FileStream("tulipfarm.gif", FileMode.Open, FileAccess.Read, FileShare.Read);
GifBitmapDecoder decoder = new GifBitmapDecoder(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
BitmapSource bitmapSource = decoder.Frames[0];
// Draw the Image
Image myImage = new Image();
myImage.Source = bitmapSource;
myImage.Stretch = Stretch.None;
myImage.Margin = new Thickness(20);
// Open a Stream and decode a GIF image
Stream^ imageStreamSource = gcnew FileStream("tulipfarm.gif", FileMode::Open, FileAccess::Read, FileShare::Read);
GifBitmapDecoder^ decoder = gcnew GifBitmapDecoder(imageStreamSource, BitmapCreateOptions::PreservePixelFormat, BitmapCacheOption::Default);
BitmapSource^ bitmapSource = decoder->Frames[0];
// Draw the Image
Image^ myImage = gcnew Image();
myImage->Source = bitmapSource;
myImage->Stretch = Stretch::None;
myImage->Margin = System::Windows::Thickness(20);
This example demonstrates how to encode a BitmapSource into a GIF image using a GifBitmapEncoder.
Dim width As Integer = 128
Dim height As Integer = width
Dim stride As Integer = CType(width / 8, Integer)
Dim pixels(height * stride) As Byte
' Define the image palette
Dim myPalette As BitmapPalette = BitmapPalettes.WebPalette
' 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("new.gif", FileMode.Create)
Dim encoder As New GifBitmapEncoder()
Dim myTextBlock As New TextBlock()
myTextBlock.Text = "Codec Author is: " + encoder.CodecInfo.Author.ToString()
encoder.Frames.Add(BitmapFrame.Create(image))
encoder.Save(stream)
int width = 128;
int height = width;
int stride = width / 8;
byte[] pixels = new byte[height * stride];
// Define the image palette
BitmapPalette myPalette = BitmapPalettes.WebPalette;
// 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("new.gif", FileMode.Create);
GifBitmapEncoder encoder = new GifBitmapEncoder();
TextBlock myTextBlock = new TextBlock();
myTextBlock.Text = "Codec Author is: " + encoder.CodecInfo.Author.ToString();
encoder.Frames.Add(BitmapFrame.Create(image));
encoder.Save(stream);
int width = 128;
int height = width;
int stride = width / 8;
array<System::Byte>^ pixels = gcnew array<System::Byte>(height * stride);
// Define the image palette
BitmapPalette^ myPalette = BitmapPalettes::WebPalette;
// 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 = gcnew FileStream("new.gif", FileMode::Create);
GifBitmapEncoder^ encoder = gcnew GifBitmapEncoder();
TextBlock^ myTextBlock = gcnew TextBlock();
myTextBlock->Text = "Codec Author is: " + encoder->CodecInfo->Author->ToString();
encoder->Frames->Add(BitmapFrame::Create(image));
encoder->Save(stream);
System..::.Object
System.Windows.Threading..::.DispatcherObject
System.Windows.Media.Imaging..::.BitmapDecoder
System.Windows.Media.Imaging..::.GifBitmapDecoder
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0
Reference
Other Resources