Calculate Height/Width Of Images
If you have a web site where users attach GIF/JPG files (like a company logo, for example) you can determine the height and width of the files with this bit of LotusScript code. Once you have the height and width, you can save that as part of the document with the attachment and then use that information when displaying the image. This will allow the browser to allocate the correct amount of space on the screen when generating the HTML, becuase the image always takes a bit longer to load than it takes the HTML to be rendered.

THIS CODE HAS BEEN CHANGED. It was discovered that JPG format wasn't as basic as the old version of the code made it out to be. After doing a lot of research on the internet, the code has been updated to (hopefully) handle JPG's correctly. It has passed several tests, but there are a few different standards for JPG's, so this may still need to "evolve" more in the future.

Function ImageSize(fileName As String) As Variant
' Given a source file name (path to the GIF or JPG on disk), return an array containing
' the width (1st element) and height (2nd element).
Dim retVal As Variant
Dim f As Integer
Dim wHi As Variant
Dim wLo As Variant
Dim hHi As Variant
Dim hLo As Variant
Dim w As Integer ' width of image
Dim h As Integer ' height of image
Dim foundMarker As Integer

Redim retVal(2) As Integer
Redim retVal(Lbound(retVal)+1)     ' Size it so there's 2 entries
retVal(Lbound(retVal)) = 0
retVal(Ubound(retVal)) = 0
f = Freefile()
On Error Resume Next
Open fileName For Input As #f
On Error Goto 0
If Err <> 0 Then
ImageSize = retVal  ' File name incorrect - return zero for both the height and width
Exit Function
End If
If Lcase(Right(fileName, 3)) = "gif" Then
' GIF's height and width stored in a fixed location
w = Asc(wHi) * 256 + Asc(wLo)
h = Asc(hHi) * 256 + Asc(hLo)
Elseif Lcase(Right(fileName, 3)) = "jpg" Then
' JPG's stored in a variable location. The code has been verified with JFIF
' file format (the most common format)
On Error Goto EndOfFile     ' In case we run over the file for some reason
foundMarker = False   ' Look for the marker that will contain the height and width
header = Input(2, f)    ' Grab the next marker
' Look for the marker (in hex) FF C0, FF C1, FF C2, or FF C3
If header = Chr\$(255) & Chr\$(192) Or header = Chr\$(255) & Chr\$(193) _
Or header = Chr\$(255) & Chr\$(194) Or header = Chr\$(255) & Chr\$(195) Then
' Next two bytes are the length, then a single byte that can be ignored.
' Next two bytes are the height of the image
h = hHi * 256 + hLo
' Next two bytes are the width of the image
w = wHi * 256 + wLo
foundMarker = True     ' Exit the while loop
Else   ' It's not one of the special markers - skip over it
header = Input(2, f)   ' Next two bytes are the marker length
w = wHi * 256 + wLo
header = Input(w-2, f) ' Skip over that many bytes (minus the 2 byte length already read)
w = 0   ' Clear the variable
End If
Wend   ' Continue until the marker is found
End If    ' Ends the check to see if the file starts with FF D8
EndOfFile:
If Err <> 0 Then
Err = 0
Resume AfterError
End If
End If   ' Ends the check to see if the format is GIF or JPG
AfterError:
retVal(Lbound(retVal)) = w
retVal(Ubound(retVal)) = h
Close #f
ImageSize = retVal
End Function