AdaptiveImage.cs

if (source.HiResSource != null)
{
    this.ProgressIndicator.IsActive = true;
    this.LayoutRoot.Children.Add(this.ProgressIndicator);

    var hiResSource = new BitmapImage();

    hiResSource.ImageOpened += this.ImageOpened;
    hiResSource.ImageFailed += this.ImageFailed;

    hiResSource.UriSource = new Uri(source.HiResSource);

    this.HiResImage = new Image { Source = hiResSource };

    this.LayoutRoot.Children.Add(this.HiResImage);

    this.HiResImage.Visibility = Visibility.Collapsed;
}