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BitmapEncoder.Palette Property

  • Reference

Definition

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

Gets or sets a value that represents the BitmapPalette of an encoded bitmap.

public:
 virtual property System::Windows::Media::Imaging::BitmapPalette ^ Palette { System::Windows::Media::Imaging::BitmapPalette ^ get(); void set(System::Windows::Media::Imaging::BitmapPalette ^ value); };
public virtual System.Windows.Media.Imaging.BitmapPalette Palette { get; set; }
member this.Palette : System.Windows.Media.Imaging.BitmapPalette with get, set
Public Overridable Property Palette As BitmapPalette

Property Value

BitmapPalette

An instance of BitmapPalette.

Exceptions

ArgumentNullException

The BitmapPalette value that is passed to the encoder is null.

Examples

The following example demonstrates how to apply a custom palette to a Tagged Image File Format (TIFF) image and subsequently encode it.

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)

Remarks

Only Tagged Image File Format (TIFF) and Graphics Interchange Format (GIF) images (and some older, non-standard bitmap (BMP) images) support palettes.

Applies to

See also