How to convert Image to ImageSource

Question

I don't know if I'm even asking the right question; so apologies in advance. I am writing some PNGs to a canvas and I also want to simultaneously copy the PNGs to a bitmap. I want the PNGs to appear in the same locations on the bitmap as they do on the canvas.

This is the code snippet:

WorkingBMP = new RenderTargetBitmap(BOARD_WIDTH, BOARD_HEIGHT, 96, 96, PixelFormats.Pbgra32);

TreeFile = "pack://application:,,,/Images/" + TreeFile;

var image = new Image
{
    Source = new BitmapImage(new Uri(TreeFile))
};
image.Width = 10;
image.Height = 10;

Canvas.SetLeft(image, x );
Canvas.SetTop(image, y );

DrawingVisual drawingVisual = new DrawingVisual();
DrawingContext drawingContext = drawingVisual.RenderOpen();
drawingContext.DrawImage(image, new Rect(x, y, image.Width, image.Height));
drawingContext.Close();

WorkingBMP.Render(drawingVisual);

MainCanvas.Children.Add(image);

HOWEVER, it throws the error "cannot convert from 'System.Windows.Controls.Image' to 'System.Windows.Media.ImageSource' on this line:

drawingContext.DrawImage(image,
                  new Rect(x, y, image.Width, image.Height));

Will this error be solved if I can somehow convert image to to an ImageSource or am I going about this all wrong?

Thanks!

In the code above, you _create_ a [`BitmapImage`](https://msdn.microsoft.com/en-us/library/system.windows.media.imaging.bitmapimage(v=vs.110).aspx) object, which _is_ an `ImageSource` (standard OOP/Liskov substitution/etc.). Why don't you just use that object? Why are you trying to convert a WPF UI element to something it's not? — Peter Duniho, Mar 03 '17 at 17:16

Arsen Mkrtchyan · Accepted Answer · 2017-03-03T16:28:54.523

1

If BitmapImage drawn directly, it should work

var source = new BitmapImage(new Uri(TreeFile))

drawingContext.DrawImage(source,
                  new Rect(x, y, image.Width, image.Height));

edited Mar 03 '17 at 16:28

answered Mar 03 '17 at 16:21

Arsen Mkrtchyan

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Thanks! Much appreciated! – zetar Mar 03 '17 at 17:16

score 0 · Answer 2 · answered Mar 03 '17 at 16:20

Image is the control on the window. Image.Source is the actual bitmap Image retrieves to render. It may not be apparent, but your code does kind of hint at this because you are setting Source to your BitmapImage.

You need to use the source property in order to get your actual BitmapImage you instantiated.

You may need to cast, but this should work:

drawingContext.DrawImage(image.Source,
                  new Rect(x, y, image.Width, image.Height));

score -1 · Answer 3 · edited Mar 03 '17 at 16:40

Here Try this

WorkingBMP = new RenderTargetBitmap(BOARD_WIDTH, BOARD_HEIGHT, 96, 96, PixelFormats.Pbgra32);

TreeFile = "pack://application:,,,/Images/" + TreeFile;

var image = new Image
{
    Source = new BitmapImage(new Uri(TreeFile))
};
image.Width = 10;
image.Height = 10;

Canvas.SetLeft(image, x );
Canvas.SetTop(image, y );

DrawingVisual drawingVisual = new DrawingVisual();
DrawingContext drawingContext = drawingVisual.RenderOpen();
drawingContext.DrawImage(new BitmapImage(new Uri(TreeFile)), new Rect(x, y, image.Width, image.Height));
drawingContext.Close();

WorkingBMP.Render(drawingVisual);

MainCanvas.Children.Add(image);

How to convert Image to ImageSource

3 Answers3