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POConvert WPF Control to BitmapSource
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copied!<p>This is kind of a two part question- First, why doesn't this code work?</p> <pre><code>Canvas canvas = new Canvas { Width = 640, Height = 480 }; System.Windows.Size size = new System.Windows.Size( canvas.Width, canvas.Height); //Measure and arrange the surface canvas.Measure( size ); canvas.Arrange( new Rect( size ) ); canvas.Background = new SolidColorBrush( Colors.Purple ); RenderTargetBitmap bitmap = new RenderTargetBitmap( (int)canvas.Width, (int)canvas.Height, 96d, 96d, PixelFormats.Pbgra32 ); bitmap.Render( canvas ); BitmapEncoder encoder = new BmpBitmapEncoder(); encoder.Frames.Add( BitmapFrame.Create( bitmap ) ); using ( MemoryStream outStream = new MemoryStream() ) { encoder.Save( outStream ); outStream.Seek( 0, SeekOrigin.Begin ); BitmapImage bmp = new BitmapImage { CacheOption = BitmapCacheOption.OnLoad }; bmp.BeginInit(); bmp.StreamSource = outStream; bmp.EndInit(); } </code></pre> <p>When I write the image to disk, all I see is a black image- I've done this before and had no problems, but now something is escaping me... I've checked the width and height and the buffer data in the MemoryStream and everything look okay...</p> <p>This is just a test, the real goal would be to create a BitmapSource from the Canvas visual image. The Canvas is getting drawn on with Shapes (polylines etc) in code. I then need to pass this BitmapSource to an Image in xaml, at a rate of about 60 frames per second. I noticed that the Image.Source is using CachedBitmap if I create a mock BitmapSource, but it is rebinding to my BitmapImage everytime I update my (black) Bitmap.</p> <p>Suggestions on how to create a Canvas in memory at 60fps and create a BitmapSource from it that is seen by Image.Source as a CachedBitmap?</p>

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