Determine file type: text or binary

[michaelslamet]

How to check if a file is a text file or a binary file without see the file extension?

Binary example: doc, swf, exe, zip, rar, jpg, png, gif

Text example: txt, xml, ini, inf, log

Thanks

[KaFu]

http://mark0.net/code-tridlib-e.html

[michaelslamet]

http://mark0.net/code-tridlib-e.html

 

Looks promising, especially this library also used in SMF! thanks!

Unfortunetely, no matter what file I put to analyzed, it always display: "Unknown filetype!"

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; TrIDlib AutoIt Demo
; http://mark0.net/code-tridlib-e.html

#include "TrIDLib-const.au3"

$MyFile = "c:\temp\11.jpg" ; a random file to analyze
$Buf = "" ; allocate a string for the results

$Dll = DllOpen("TrIDLib.DLL") ; Open TrIDLib DLL

$Ret = DllCall($Dll, "int", "TrID_LoadDefsPack", "str", "") ; load the definitions
$Ret = DllCall($Dll, "int", "TrID_SubmitFileA", "str", $MyFile) ; submit the file
$Ret = DllCall($Dll, "int", "TrID_Analyze") ; perform the analysis

if @error = 1 then
    MsgBox(48, "TrID_Analyze", "Error(s) occurred!")
Else
    $Ret = DllCall($Dll, "int", "TrID_GetInfo", "int", $TRID_GET_RES_NUM, "int", 0, "str", $Buf)
    $ResNum = $Ret[0] ; get the results number
    $Out = ""
    if $ResNum = 0 Then
        $Out = "Unknown filetype!"
    Else
        For $ResId = 1 to $ResNUm ; cycle trough results
            $Ret = DllCall($Dll, "int", "TrID_GetInfo", "int", $TRID_GET_RES_FILETYPE, "int", $ResId, "str", $Buf)
            $Out = $Out & $ResId & ":" & Chr(9) &  $Ret[3] ; get the filetype description
            $Ret = DllCall($Dll, "int", "TrID_GetInfo", "int", $TRID_GET_RES_FILEEXT, "int", $ResId, "str", $Buf)
            $Out = $Out & " (" & $Ret[3] & ")" ; get the filetype extension
            $Ret = DllCall($Dll, "int", "TrID_GetInfo", "int", $TRID_GET_RES_POINTS, "int", $ResId, "str", $Buf)
            $Out = $Out & " - " & $Ret[0] ; get the matching points
            $Out = $Out & Chr(13)
        Next
    EndIf
    MsgBox(0, "TrIDLib demo", $Out)
EndIf

DllClose($Dll) ; cleanup

 

WinXP, AutoIT 3.8.8.1

What did I do wrong?

[KaFu]

I guess you did not download the TrIDDefs.TRD package from here: http://mark0.net/soft-trid.html]

Edited April 8, 2014 by KaFu

[michaelslamet]

I guess you did not download the TrIDDefs.TRD package from here: http://mark0.net/soft-trid.html

TrId.zip

 

Thank you again, KaFu. You're correct

Now it's working to .jpg and .exe files, but when it come to text file (.txt, .au3) why it always return "Unknown filetype!" ?

Test and see yourself

[KaFu]

In SMF I replaced "unkown" with "Indeterminable (e.g. text-file) / unknown filetype". There is nothing unique about a txt file, except from the extension it could also be an .au3 file, an .html file or a .py file... TrID is looking for file specific patterns / headers (jpg, zip, exe), but txt files just don't have these kind of patterns.

[michaelslamet]

In SMF I replaced "unkown" with "Indeterminable (e.g. text-file) / unknown filetype". There is nothing unique about a txt file, except from the extension it could also be an .au3 file, an .html file or a .py file... TrID is looking for file specific patterns / headers (jpg, zip, exe), but txt files just don't have these kind of patterns.

 

aha! understand now

So could I say if it is detected as "unknown", it's quite a big chance it's a text file? Not 100% for sure, but pretty big chance?

[KaFu]

Hmmm, yes, I would think so, not 100% for sure, but pretty big chance is a good summary ...

[michaelslamet]

Hmmm, yes, I would think so, not 100% for sure, but pretty big chance is a good summary ...

 

Ok, I'm going to do some experiment with it. Thanks, KaFu

[aVen9er]

Func FileIsBinary($nazwa_pliku)
    Local $iMaxLiczbaZnakow = 100
    If Not FileExists($nazwa_pliku) Then    Return -1

    Local $iFile = FileOpen($nazwa_pliku)
    Local $strZaw = FileRead($iFile, $iMaxLiczbaZnakow)
    FileClose($iFile)

    Return IsBinary($strZaw)
EndFunc