title: WriteableBitmap in .NET Standard 2.0
body: <p>I have a working <code>ASP.NET WebAPI</code> which processes images, I'm trying to port the API over to <code>Azure Functions</code> (<code>.NET Standard 2.0</code>). I was able to migrate most of the functionality except one piece. I'm using <code>WriteableBitmap</code> to perform some manipulations on the image - it seems that the class is not available in .NET Standard 2.0. I get the following error message in Visual Studio 2017, but I can't add a reference to <code>PresentationCore</code> since it's not available at the references window. </p>
  
  <pre><code>The type 'WriteableBitmap' is defined in an assembly that is not referenced. You must add a reference to assembly 'PresentationCore, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'
  </code></pre>
  
  <p>Has anyone experienced a similar problem or can help me out here?</p>
  
  <p>//EDIT:
  Here is the code which I use to create the <code>WriteableBitmap</code></p>
  
  <pre><code>var width = array.Columns;
  var height = array.Rows;
  var rgbReverse = true;
  var format = PixelFormats.Bgr24;
  var channels = 3;
  var bitmap = new WriteableBitmap(width, height, dpiX, dpiY, format, null);
  </code></pre>