title: PdfSharpCore image rendering issue
body: <p>Completely unable to render JPEG image to PDF using PdfSharpCore.</p>
  
  <p>Code is as simple as </p>
  
  <pre><code>public byte[] GetPdfContent()
  {
      ImageSource.ImageSourceImpl = new ImageSharpImageSource();
  
      var document = new PdfDocument();
      var logo = XImage.FromFile("logo.jpg");
  
      // this is test line, I'm saving XImage result and it is identical to the source file!
      File.WriteAllBytes("logo1.jpg", logo.AsJpeg().ToArray());
  
      var page = document.AddPage();
      var gfx = XGraphics.FromPdfPage(page);
      gfx.DrawImage(logo, 0, 0);
  
      using (var stream = new MemoryStream())
      {
           document.Save(stream, false);
           return stream.ToArray();
      }
  }
  </code></pre>
  
  <p>I know that <code>ImageSource.ImageSourceImpl</code> has to be set, and I've set it to the simplest <code>ImageSharp</code>-based implementation: <code>ImageSource.ImageSourceImpl = new ImageSharpImageSource()</code> which is indeed valid because XImage is being saved as <code>logo1.jpg</code> properly. </p>
  
  <p>But my PDF is visually blank. Binary content is there, and it seem that all format properties are OK, but binary data is somewhat different from the source.</p>
  
  <p>Here is how my ImageSharp implementation saves/loads the image:</p>
  
  <pre><code>public class ImageSharpImageSource : ImageSource
  {
      protected override IImageSource FromFileImpl(string path, int? quality = 75)
      {
          return new ImageSharpImageSourceImpl(path, () =&gt;
          {
              return Image.Load&lt;Rgb24&gt;(path, new JpegDecoder());
          }, (int)quality);
      }
  
      private class ImageSharpImageSourceImpl : IImageSource
      { 
          public void SaveAsJpeg(MemoryStream ms)
          {
              Image.SaveAsJpeg(ms, new JpegEncoder());
          }
      }
  }
  </code></pre>
  
  <p>Finally, PDF piece:</p>
  
  <pre><code>7 0 obj   % PdfSharpCore.Pdf.Advanced.PdfImage
  &lt;&lt;
    /BitsPerComponent 8
    /ColorSpace /DeviceRGB
    /Filter /DCTDecode
    /Height 340
    /Interpolate true
    /Length 16443
    /Subtype /Image
    /Type /XObject
    /Width 340
  &gt;&gt;
  stream &lt;&lt;BINARY DATA&gt;&gt;
  </code></pre>
  
  <p>Please help, I'm stuck for a few days! New to this stuff so probably missing something?..</p>
  
  <p>NOTE: <code>gfx.DrawString()</code> methods work properly, so I'm able to render text with the same setup.</p>