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BitmapEncoder.Palette Propriété

  • Référence

Définition

Espace de noms:
System.Windows.Media.Imaging
Assembly:
PresentationCore.dll

Obtient ou définit une valeur qui représente la BitmapPalette d’une bitmap encodée.

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

Valeur de propriété

BitmapPalette

Instance de BitmapPalette.

Exceptions

ArgumentNullException

La valeur de BitmapPalette passée à l’encodeur est null.

Exemples

L’exemple suivant montre comment appliquer une palette personnalisée à une image TIFF (Tagged Image File Format) et l’encoder ultérieurement.

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)

Remarques

Seules les images TIFF (Tagged Image File Format) et les images GIF (Graphics Interchange Format) (et certaines images bitmap non standard( BMP) anciennes prennent en charge les palettes.

S’applique à

Voir aussi