title: C# saving multiple png file from a MemoryStream
body: <p>I am getting multiple pngs from another process from its standard output as a stream. I want to take this memory stream and save it as multiple png files. I have looked at <code>PngBitmapEncoder/PngBitmapDecoder</code>, but I can't seem to get a multiple page out of it (whenever I create a decoder using <code>PngBitmapDecoder.Create</code>, <code>decoder.Frames.Count</code> is always 1. Here is how I create the decoder: </p>
  
  <pre><code>BitmapDecoder decoder = PngBitmapDecoder.Create(memStream,
                                                  BitmapCreateOptions.PreservePixelFormat,
                                                  BitmapCacheOption.Default);
  </code></pre>
  
  <p>Am I doing something wrong? </p>