Help wanted clipping an image region and saving as new bitmap

Question

Can someone please help me.

What I what to do is display a picture (image) and drawer a clip region using the mouse on a selected area on the image, this could be a retangle, square or a freehand shape, I think this could be done using path geometries and clip.

I can get to the point of creating the clipped image as in this example.
http://msdn.microsoft.com/en-us/library/ms751808(VS.85).aspx

but what I now want to do is save the clipped image as a new image (bitmap).

but I am not sure how to do this.

does anyone have any sample code, or suggestions.

This can be in either vb.net or c#

Thanks

Peter Martin · Answer

Hi Thanks you for your reply. In the example below if I create a clipped region around an image what would I pass in as the rendered bitmap. The same if I created an image and added a pathgeometry to only show part of the image how to I passing only the clipped part of the image. // Sample 4 // Create the image to clip. Image myImage = new Image (); Uri imageUri = new Uri ( @C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water lilies.jpg  UriKind .Relative); myImage.Source = new BitmapImage (imageUri); myImage.Width = 200; myImage.Height = 150; myImage.HorizontalAlignment = HorizontalAlignment .Left; // Use an EllipseGeometry to define the clip region. EllipseGeometry myEllipseGeometry2 = new EllipseGeometry (); myEllipseGeometry2.Center = new Point (100 75); myEllipseGeometry2.RadiusX = 100; myEllipseGeometry2.RadiusY = 75; myImage.Clip = myEllipseGeometry2;

James Tomar · Answer

// Create a render bitmap and push the surface to it RenderTargetBitmap renderBitmap = new RenderTargetBitmap ( ( int )size.Width ( int )size.Height 96d 96d PixelFormats .Pbgra32); renderBitmap.Render(yourui); // Encode the image in the format selected System.Windows.Media.Imaging. BitmapEncoder encoder = default System.Windows.Media.Imaging. BitmapEncoder ); // Create a file stream for saving image using ( FileStream outStream = new FileStream (fileName FileMode .Create)) { switch (fileExtension.ToLower()) { case .jpg : case .jpeg : encoder = new System.Windows.Media.Imaging. JpegBitmapEncoder (); break ; case .png : encoder = new System.Windows.Media.Imaging. PngBitmapEncoder (); break ; case .gif : encoder = new System.Windows.Media.Imaging. GifBitmapEncoder (); break ; case .bmp : encoder = new System.Windows.Media.Imaging. BmpBitmapEncoder (); break ; case .tif : case .tiff : encoder = new System.Windows.Media.Imaging. TiffBitmapEncoder (); break ; } // push the rendered bitmap to it encoder.Frames.Add( BitmapFrame .Create(renderBitmap)); // save the data to the stream encoder.Save(outStream); }