BitmapDecoder class (Windows)

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Provides read access to bitmap container data as well as data from the first frame.

Syntax


var bitmapDecoder = Windows.Graphics.Imaging.BitmapDecoder;

Attributes

MarshalingBehaviorAttribute(Agile)
StaticAttribute(Windows.Graphics.Imaging.IBitmapDecoderStatics, NTDDI_WIN8)
VersionAttribute(NTDDI_WIN8)

Members

The BitmapDecoder class has these types of members:

Methods
Properties

Methods

The BitmapDecoder class has these methods. With C#, Visual Basic, and C++, it also inherits methods from the Object class.

Method	Description
CreateAsync(Guid, IRandomAccessStream)	Asynchronously creates a new BitmapDecoder using a specific bitmap codec and initializes it using a stream.
CreateAsync(IRandomAccessStream)	Asynchronously creates a new BitmapDecoder and initializes it using a stream.
GetDecoderInformationEnumerator	The bitmap decoders installed on the system and information about them.
GetFrameAsync	Asynchronously retrieves a frame from the image file.
GetPixelDataAsync()	Asynchronously requests the pixel data for the frame.
GetPixelDataAsync(BitmapPixelFormat, BitmapAlphaMode, BitmapTransform, ExifOrientationMode, ColorManagementMode)	Asynchronously requests the pixel data for the frame using the specified parameters.
GetPreviewAsync	Asynchronously returns a stream containing the preview image.
GetThumbnailAsync	Asynchronously returns a stream containing the thumbnail image.

Properties

The BitmapDecoder class has these properties.

Property	Access type	Description
BitmapAlphaMode	Read-only	The default alpha mode of the first frame.
BitmapContainerProperties	Read-only	Provides access to the container bitmap properties.
BitmapPixelFormat	Read-only	The pixel format that best fits the first frame.
BitmapProperties	Read-only	A read-only view of the metadata within the first frame.
BmpDecoderId	Read-only	The unique identifier of the BMP decoder.
DecoderInformation	Read-only	Information about the bitmap decoder.
DpiX	Read-only	The horizontal resolution of the first frame in dots per inch.
DpiY	Read-only	The vertical resolution of the first frame in dots per inch.
FrameCount	Read-only	The number of frames within the image file.
GifDecoderId	Read-only	The unique identifier of the GIF decoder.
IcoDecoderId	Read-only	The unique identifier of the ICO decoder.
JpegDecoderId	Read-only	The unique identifier of the JPEG decoder.
JpegXRDecoderId	Read-only	The unique identifier of the JPEG-XR decoder.
OrientedPixelHeight	Read-only	The height of the first frame in pixels, after any EXIF orientation has been applied to the bitmap.
OrientedPixelWidth	Read-only	The width of the first frame in pixels, after any EXIF orientation has been applied to the bitmap.
PixelHeight	Read-only	The height of the first frame in pixels.
PixelWidth	Read-only	The width of the first frame in pixels.
PngDecoderId	Read-only	The unique identifier of the PNG decoder.
TiffDecoderId	Read-only	The unique identifier of the TIFF decoder.

Remarks

The BitmapDecoder class implements IBitmapFrame. It provides access to container data as well as data from the first frame. This allows applications to accomplish most common scenarios without needing to retrieve a separate BitmapFrame.

Examples

Here's a partial example of creating a decoder object. This example assumes you selected a file with Windows.Storage.Pickers.FileOpenPicker. For full instructions on selecting a file, creating an decoder, and decoding an image see How to decode an image

JavaScript


file.openAsync(Windows.Storage.FileAccessMode.readWrite).then(function (_stream) {
        stream = _stream;

        var encoderId;
        switch (fileType) {
            case ".jpg":
                encoderId = Windows.Graphics.Imaging.BitmapEncoder.jpegEncoderId;
                break;
        }
        return Windows.Graphics.Imaging.BitmapEncoder.createAsync(encoderId, stream);
        }).then(function (encoder) {

														// Your code here.
	       }

Requirements

Minimum supported client	Windows 8 [Windows Store apps only]
Minimum supported server	Windows Server 2012 [Windows Store apps only]
Namespace	Windows.Graphics.Imaging Windows::Graphics::Imaging [C++]
Metadata	Windows.winmd

Build date: 12/4/2012

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