<%
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\'::: BMP, GIF, JPG and PNG :::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\'::: :::
　　\'::: This function gets a specified number of bytes from any :::
　　\'::: file, starting at the offset (base 1) :::
　　\'::: :::
　　\'::: Passed: :::
　　\'::: flnm => Filespec of file to read :::
　　\'::: offset => Offset at which to start reading :::
　　\'::: bytes => How many bytes to read :::
　　\'::: :::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　function GetBytes(flnm, offset, bytes)
　　Dim objFSO
　　Dim objFTemp
　　Dim objTextStream
　　Dim lngSize
　　on error resume next
　　Set objFSO = CreateObject("Scripting.FileSystemObject")

\' First, we get the filesize
　　Set objFTemp = objFSO.GetFile(flnm)
　　lngSize = objFTemp.Size
　　set objFTemp = nothing
　　fsoForReading = 1
　　Set objTextStream = objFSO.OpenTextFile(flnm, fsoForReading)
　　if offset > 0 then
　　strBuff = objTextStream.Read(offset - 1)
　　end if
　　if bytes = -1 then \' Get All!
　　GetBytes = objTextStream.Read(lngSize) \'ReadAll
　　else
　　GetBytes = objTextStream.Read(bytes)
　　end if
　　objTextStream.Close
　　set objTextStream = nothing
　　set objFSO = nothing
　　end function

\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\'::: :::
　　\'::: Functions to convert two bytes to a numeric value (long) :::
　　\'::: (both little-endian and big-endian) :::
　　\'::: :::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　function lngConvert(strTemp)
　　lngConvert = clng(asc(left(strTemp, 1)) + ((asc(right(strTemp, 1)) * 256)))
　　end function
　　function lngConvert2(strTemp)
　　lngConvert2 = clng(asc(right(strTemp, 1)) + ((asc(left(strTemp, 1)) * 256)))
　　end function

\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\'::: :::
　　\'::: This function does most of the real work. It will attempt :::
　　\'::: to read any file, regardless of the extension, and will :::
　　\'::: identify if it is a graphical image. :::
　　\'::: :::
　　\'::: Passed: :::
　　\'::: flnm => Filespec of file to read :::
　　\'::: width => width of image :::
　　\'::: height => height of image :::
　　\'::: depth => color depth (in number of colors) :::
　　\'::: strImageType=> type of image (e.g. GIF, BMP, etc.) :::
　　\'::: :::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　function gfxSpex(flnm, width, height, depth, strImageType)
　　dim strPNG
　　dim strGIF
　　dim strBMP
　　dim strType
　　strType = ""
　　strImageType = "(unknown)"
　　gfxSpex = False
　　strPNG = chr(137) & chr(80) & chr(78)
　　strGIF = "GIF"
　　strBMP = chr(66) & chr(77)
　　strType = GetBytes(flnm, 0, 3)
　　if strType = strGIF then \' is GIF
　　strImageType = "GIF"
　　Width = lngConvert(GetBytes(flnm, 7, 2))
　　Height = lngConvert(GetBytes(flnm, 9, 2))
　　Depth = 2 ^ ((asc(GetBytes(flnm, 11, 1)) and 7) + 1)
　　gfxSpex = True
　　elseif left(strType, 2) = strBMP then \' is BMP
　　strImageType = "BMP"
　　Width = lngConvert(GetBytes(flnm, 19, 2))
　　Height = lngConvert(GetBytes(flnm, 23, 2))
　　Depth = 2 ^ (asc(GetBytes(flnm, 29, 1)))
　　gfxSpex = True
　　elseif strType = strPNG then \' Is PNG
　　strImageType = "PNG"
　　Width = lngConvert2(GetBytes(flnm, 19, 2))
　　Height = lngConvert2(GetBytes(flnm, 23, 2))
　　Depth = getBytes(flnm, 25, 2)
　　select case asc(right(Depth,1))
　　case 0
　　Depth = 2 ^ (asc(left(Depth, 1)))
　　gfxSpex = True
　　case 2
　　Depth = 2 ^ (asc(left(Depth, 1)) * 3)
　　gfxSpex = True
　　case 3
　　Depth = 2 ^ (asc(left(Depth, 1))) \'8
　　gfxSpex = True
　　case 4
　　Depth = 2 ^ (asc(left(Depth, 1)) * 2)
　　gfxSpex = True
　　case 6
　　Depth = 2 ^ (asc(left(Depth, 1)) * 4)
　　gfxSpex = True
　　case else
　　Depth = -1
　　end select

else
　　strBuff = GetBytes(flnm, 0, -1) \' Get all bytes from file
　　lngSize = len(strBuff)
　　flgFound = 0
　　strTarget = chr(255) & chr(216) & chr(255)
　　flgFound = instr(strBuff, strTarget)
　　if flgFound = 0 then
　　exit function
　　end if
　　strImageType = "JPG"
　　lngPos = flgFound + 2
　　ExitLoop = false
　　do while ExitLoop = False and lngPos < lngSize

do while asc(mid(strBuff, lngPos, 1)) = 255 and lngPos < lngSize
　　lngPos = lngPos + 1
　　loop
　　if asc(mid(strBuff, lngPos, 1)) < 192 or asc(mid(strBuff, lngPos, 1)) > 195 then
　　lngMarkerSize = lngConvert2(mid(strBuff, lngPos + 1, 2))
　　lngPos = lngPos + lngMarkerSize + 1
　　else
　　ExitLoop = True
　　end if
　　loop
　　\'
　　if ExitLoop = False then
　　Width = -1
　　Height = -1
　　Depth = -1
　　else
　　Height = lngConvert2(mid(strBuff, lngPos + 4, 2))
　　Width = lngConvert2(mid(strBuff, lngPos + 6, 2))
　　Depth = 2 ^ (asc(mid(strBuff, lngPos + 8, 1)) * 8)
　　gfxSpex = True
　　end if

end if
　　end function

\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
　　\'::: Test Harness :::
　　\':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

\' To test, we\'ll just try to show all files with a .GIF extension in the root of C:
　　Set objFSO = CreateObject("Scripting.FileSystemObject")
　　Set objF = objFSO.GetFolder("c:")
　　Set objFC = objF.Files
　　response.write "<table border=""0"" cellpadding=""5"">"
　　For Each f1 in objFC
　　if instr(ucase(f1.Name), ".GIF") then
　　response.write "<tr><td>" & f1.name & "</td><td>" & f1.DateCreated & "</td><td>" & f1.Size & "</td><td>"
　　if gfxSpex(f1.Path, w, h, c, strType) = true then
　　response.write w & " x " & h & " " & c & " colors"
　　else
　　response.write " "
　　end if
　　response.write "</td></tr>"
　　end if
　　Next
　　response.write "</table>"
　　set objFC = nothing
　　set objF = nothing
　　set objFSO = nothing
　　%>