Wednesday, June 23, 2004

Get the Compression Method of a TIFF in VB.NET (Visual Basic.NET)

This really bugged me. I found code all over the web for how to convert a TIFF from one compression format to another and how to convert a TIFF to every other kind of file format that .NET supports, but nowhere could I find a code snippet showing me how to know what compression method a TIFF is currently using except for a lone post on Google Groups.

So I am posting the code for knowing what the compression method of a TIFF is in VB.NET.

Private Function GetTiffCompressionType(ByVal FilePath As String) As Int32

Dim img As Bitmap
Dim c As Int32

img = img.FromFile(FilePath)
c = Int32.Parse(img.GetPropertyItem(259).Value(0))
Catch ex As Exception
c = -1
End Try

'Return value:
'1 = ???
'2 = CCIT 3 (modified)
'3 = CCIT 3
'4 = CCIT 4
'5 = PackBits
'That's all I've discovered so far.
Return c

End Function