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Gewusst wie: Anwenden einer Transformation auf ein Bitmapbild

In diesem Beispiel wird das Anwenden einer Transform auf ein BitmapImage veranschaulicht.

Beispiel

'/// Create a BitmapImage and set it's DecodePixelWidth to 200. Use  /////
'/// this BitmapImage as a source for other BitmapSource objects.    /////
Dim myBitmapImage As New BitmapImage()

' BitmapSource objects like BitmapImage can only have their properties
' changed within a BeginInit/EndInit block.
myBitmapImage.BeginInit()
myBitmapImage.UriSource = New Uri("C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water Lilies.jpg")

' To save significant application memory, set the DecodePixelWidth or  
' DecodePixelHeight of the BitmapImage value of the image source to the desired 
' height or width of the rendered image. If you don't do this, the application will 
' cache the image as though it were rendered as its normal size rather then just 
' the size that is displayed.
' Note: In order to preserve aspect ratio, set DecodePixelWidth
' or DecodePixelHeight but not both.
myBitmapImage.DecodePixelWidth = 200
myBitmapImage.EndInit()

'///////////////// Create a BitmapSource that Rotates the image //////////////////////
' Use the BitmapImage created above as the source for a new BitmapSource object
' that will be scaled to a different size. Create a new BitmapSource by   
' scaling the original one.                                               
' Note: New BitmapSource does not cache. It is always pulled when required.
' Create the new BitmapSource that will be used to scale the size of the source.
Dim myRotatedBitmapSource As New TransformedBitmap()

' BitmapSource objects like TransformedBitmap can only have their properties
' changed within a BeginInit/EndInit block.
myRotatedBitmapSource.BeginInit()

' Use the BitmapSource object defined above as the source for this BitmapSource.
' This creates a "chain" of BitmapSource objects which essentially inherit from each other.
myRotatedBitmapSource.Source = myBitmapImage

' Flip the source 90 degrees.
myRotatedBitmapSource.Transform = New RotateTransform(90)
myRotatedBitmapSource.EndInit()
///// Create a BitmapImage and set it's DecodePixelWidth to 200. Use  /////
///// this BitmapImage as a source for other BitmapSource objects.    /////

BitmapImage myBitmapImage = new BitmapImage();

// BitmapSource objects like BitmapImage can only have their properties
// changed within a BeginInit/EndInit block.
myBitmapImage.BeginInit();
myBitmapImage.UriSource = new Uri(@"C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water Lilies.jpg");

// To save significant application memory, set the DecodePixelWidth or  
// DecodePixelHeight of the BitmapImage value of the image source to the desired 
// height or width of the rendered image. If you don't do this, the application will 
// cache the image as though it were rendered as its normal size rather then just 
// the size that is displayed.
// Note: In order to preserve aspect ratio, set DecodePixelWidth
// or DecodePixelHeight but not both.
myBitmapImage.DecodePixelWidth = 200;
myBitmapImage.EndInit();

/////////////////// Create a BitmapSource that Rotates the image //////////////////////
// Use the BitmapImage created above as the source for a new BitmapSource object
// that will be scaled to a different size. Create a new BitmapSource by   
// scaling the original one.                                               
// Note: New BitmapSource does not cache. It is always pulled when required.

// Create the new BitmapSource that will be used to scale the size of the source.
TransformedBitmap myRotatedBitmapSource = new TransformedBitmap();

// BitmapSource objects like TransformedBitmap can only have their properties
// changed within a BeginInit/EndInit block.
myRotatedBitmapSource.BeginInit();

// Use the BitmapSource object defined above as the source for this BitmapSource.
// This creates a "chain" of BitmapSource objects which essentially inherit from each other.
myRotatedBitmapSource.Source = myBitmapImage;

// Flip the source 90 degrees.
myRotatedBitmapSource.Transform = new RotateTransform(90);
myRotatedBitmapSource.EndInit();

Siehe auch

Aufgaben

Gewusst wie: Drehen eines Bilds

Referenz

BitmapSource

Konzepte

Übersicht über die Bildverarbeitung