How to convert from type Image to type BitmapImage?

Bitmap      img   = (Bitmap) Image.FromStream(memStream);
BitmapImage bmImg = new BitmapImage();

using (MemoryStream memStream2 = new MemoryStream()) 
{
   img.Save(memStream2, System.Drawing.Imaging.ImageFormat.Png);
   memStream2.Position = 0;

   bmImg.BeginInit();
   bmImg.CacheOption = BitmapCacheOption.OnLoad;
   bmImg.UriSource = null;
   bmImg.StreamSource = memStream2;
   bmImg.EndInit();
}

From this post

public BitmapImage ImageFromBuffer(Byte[] bytes)
{
    MemoryStream stream = new MemoryStream(bytes);
    BitmapImage image = new BitmapImage();
    image.BeginInit();
    image.StreamSource = stream;
    image.EndInit();
    return image;
}