image width, height and size

ASPImage is anotyher very good component , used for this + a lot of other things
u shd get that one too from www.serverobjects.com

OR...

Sub getJPEGDimensions(ByVal filename, ByRef width, ByRef height)
     '// sets width and height to the values scooped from the JPEG referenced by filename
     '// Assumes filename supplies a full path (i.e. it has been MapPath'ed)

     Dim lBinPrefix
     Dim lLngStart
     Dim binaryData, objFS, objFile
     
     'filename = Server.MapPath(filename)
     Set objFS = Server.CreateObject("Scripting.FileSystemObject")
     
     Set objFile = objFS.OpenTextFile(filename)
     If Not objFile.AtEndOfStream Then
          binaryData = ChrB(Asc(objFile.Read(1)))
          While Not objFile.AtEndOfStream
                binaryData = binaryData & ChrB(Asc(objFile.Read(1)))
          Wend
     End If
     objFile.Close
     Set objFile = Nothing
     Set objFS = Nothing
     
     
     ' Prefix found before image dimensions          
     lBinPrefix = ChrB(&h00) & ChrB(&h11) & ChrB(&h08)
     
     ' Find the last prefix (so we don't confuse it with data)          
     lLngStart = 1
     Do
          If InStrB(lLngStart, binaryData, lBinPrefix) + 3 = 3 Then Exit Do
          lLngStart = InStrB(lLngStart, binaryData, lBinPrefix) + 3
     Loop
     ' If a prefix was found
     If Not lLngStart = 1 Then
          width = CLng("&h" & HexAt(lLngStart+2, binaryData) & HexAt(lLngStart+3, binaryData))
          height = CLng("&h" & HexAt(lLngStart, binaryData) & HexAt(lLngStart+1, binaryData))
     End If
End Sub


Function HexAt(ByRef pLngPosition, ByRef mStrBinaryData)
     If pLngPosition > LenB(mStrBinaryData) Or pLngPosition <= 0 Then Exit Function
     HexAt = Right("0" & Hex(AscB(MidB(mStrBinaryData, pLngPosition, 1))), 2)
End Function