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BitmapImage.DecodePixelWidth Property

  • Reference

Definition

Namespace:
System.Windows.Media.Imaging
Assembly:
PresentationCore.dll

Gets or sets the width, in pixels, that the image is decoded to.

public:
 property int DecodePixelWidth { int get(); void set(int value); };
public int DecodePixelWidth { get; set; }
member this.DecodePixelWidth : int with get, set
Public Property DecodePixelWidth As Integer

Property Value

Int32

The width, in pixels, that the image is decoded to. The default value is 0.

Examples

The following code example demonstrates how to set the DecodePixelWidth property by using code.

// Define a BitmapImage.
Image myImage = new Image();
BitmapImage bi = new BitmapImage();

// Begin initialization.
bi.BeginInit();

// Set properties.
bi.CacheOption = BitmapCacheOption.OnDemand;
bi.CreateOptions = BitmapCreateOptions.DelayCreation;
bi.DecodePixelHeight = 125;
bi.DecodePixelWidth = 125;
bi.Rotation = Rotation.Rotate90;
MessageBox.Show(bi.IsDownloading.ToString());
bi.UriSource = new Uri("smiley.png", UriKind.Relative);

// End initialization.
bi.EndInit();
myImage.Source = bi;
myImage.Stretch = Stretch.None;
myImage.Margin = new Thickness(5);

' Define a BitmapImage.
Dim myImage As New Image()
Dim bi As New BitmapImage()

' Begin initialization.
bi.BeginInit()

' Set properties.
bi.CacheOption = BitmapCacheOption.OnDemand
bi.CreateOptions = BitmapCreateOptions.DelayCreation
bi.DecodePixelHeight = 125
bi.DecodePixelWidth = 125
bi.Rotation = Rotation.Rotate90
MessageBox.Show(bi.IsDownloading.ToString())
bi.UriSource = New Uri("smiley.png", UriKind.Relative)

' End initialization.
bi.EndInit()
myImage.Source = bi
myImage.Stretch = Stretch.None
myImage.Margin = New Thickness(5)

Remarks

If DecodePixelHeight is also set, the aspect ratio of the bitmap is ignored. If DecodePixelHeight is not set, the aspect ratio remains the same.

The JPEG and Portable Network Graphics (PNG) codecs natively decode the image to the specified size; other codecs decode the image at its original size and scale the image to the desired size.

Dependency Property Information
Identifier field DecodePixelWidthProperty
Metadata properties set to true None

Applies to

See also