Draw PNG files from EMF files faster

Hello Experts, I use the code below to convert my EMF files to PNG files for many graphs at a time. Two of the steps are very slow: memoryGraphics.DrawImage and memoryBitmap.Save

I am asking for suggestions on how to speed these two steps up considerably, or an alternative faster way to generate the .png files from the EMF files.

'NewImage is the path to my EMF file        
Dim imgMeta As New Metafile(NewImage)
Dim myWidth As Integer
Dim myHeight As Integer
myWidth = imgMeta.Width
myHeight = imgMeta.Height
'  We want a high quality .png file.
'  Let's quadruple the height and width.
myWidth = myWidth * 4
myHeight = myHeight * 4
Dim memoryBitmap As Bitmap
memoryBitmap = New Bitmap(myWidth, myHeight) 'adds 4 seconds for 107 graphs (14 seconds to 18 seconds)
Dim memoryGraphics As Graphics
memoryGraphics = Graphics.FromImage(memoryBitmap)
' Draw the Metafile to memory
memoryGraphics.DrawImage(imgMeta, 0, 0, myWidth, myHeight) 'adds 20 seconds for 107 graphs (18 to 38)
memoryBitmap.Save(GloTempPath & "\pngversion.png", ImageFormat.Png) 'add 30 more seconds (38 to 68) 68 is total time
imgMeta.Dispose()