Create PropertyItem() for image metadata (Tiff, geotiff, exif tags)

[cgritton]

I have seen this question posted alot and have never seen a solution posted. This method will create a property item to set on a newly created bitmap. I figured this out quite some time ago and thought I'd share this handy little method. Hope it will help somebody trying to learn how to use property items for storing data with an image.

VB.NET 2003, 2005, 2008

[CODE=vbnet]
'create a new property item for use with a new bitmap
'that does not have property items
Public Function CreatePropertyI tem() As System.Drawing. Imaging.Propert yItem

'create a new bitmap (only 10x10 to minimize memory usage)
Dim bmpProps As New Bitmap(10, 10)

'create a new memory stream for manipulating the new bitmap
Dim propMS As New IO.MemoryStream

'new image is saved to stream with tiff format to create property items
bmpProps.Save(p ropMS, System.Drawing. Imaging.ImageFo rmat.Tiff)

'set the stream back to the beginning so we can read it out
propMS.Position = 0

'recreate bitmap from stream so we
'should now have available property items
bmpProps = Bitmap.FromStre am(propMS)


If bmpProps.Proper tyItems.Length > 0 Then
Return bmpProps.Proper tyItems(0)
End If

'should check for null when using
'this function just in case something wierd happened
Return Nothing
End Function
[/CODE]