MP3 Info

A class to get info from your mp3 files

Very simple, no need to rename any variable nor register any ActiveX.

Option Explicit
Class Mp3
	Private fso
	Private id3v1	'Buffer of 128 Bytes
	Private Header	'Buffer of 4 bytes starting the file
	Private LastFile

	Public Filename	'Path to the mp3 File

	Private Sub Class_Initialize   ' Initialize event.
		LastFile=""
		Set fso=WScript.CreateObject("Scripting.FileSystemObject")
	End Sub
	Private Sub Class_Terminate   ' Terminate event.
		Set fso=Nothing
	End Sub

	Private Function Test_Path
		Test_Path=False
		If fso.FileExists(FileName) Then
			Dim extension
			extension=UCase(fso.GetExtensionName(FileName))
			If extension="MP2" Or extension="MP3" Then Test_Path=True
		End If
	End Function

	Property Get FileSize
		If Not Test_Path Then Exit Property
		'If the file doesn't exist, an error is raised
		FileSize=fso.GetFile(FileName).Size
	End Property

	Sub Read_id3v1
		'Read the structure only if needed
		If LastFile<>FileName Then
			LastFile=FileName
			Dim f,Chaine
			' Read the Header
			'More info : http://www.id3.org/mp3frame.html
			Set f=fso.OpenTextFile(FileName,1,False,0)
			'Header=Asc(f.Read(1))*256+Asc(f.Read(1))+Asc(f.Read(1))*256*256+Asc(f.Read(1))*256*256*256
			Header=f.Read(4)
			If FileSize>128 Then
				f.skip(FileSize-128-4)
				id3v1=f.Read(128)
			End If
			f.Close
			Set f=Nothing
		End If
	End Sub
	Function sz2str(Chaine)
		Dim x
		x=Instr(chaine,chr(0))
		If x>0 Then Chaine=Left(Chaine,x-1)
		sz2str=Chaine
	End Function


	' --- Header ---
	'The header is followed by the audio data

	Property Get Sync	'4095 : 11 or 12 bits set
		If Not Test_Path Then Exit Property
		Read_id3v1
		Sync=Asc(Left(Header,1))+(Asc(Mid(Header,2,1))\16)*256
	End Property

	Property Get Layer
		If Not Test_Path Then Exit Property
		Read_id3v1
		Layer=Array("Not defined","Layer III","Layer II","Layer I")(Asc(Mid(Header,2,1))\2 Mod 4)
	End Property

	Property Get Prot
		If Not Test_Path Then Exit Property
		'If zero then header follwed by 16bits checksum
		Read_id3v1
		Prot=Asc(Mid(Header,2,1)) Mod 2
	End Property

	Property Get ID
		If Not Test_Path Then Exit Property
		Read_id3v1
		ID=Array("MPEG-2","MPEG-1")(Asc(Mid(Header,2,1))\8 Mod 2)
	End Property

	Property Get BitRate	'in kbits/s
		If Not Test_Path Then Exit Property
		Read_id3v1
		Select Case (Asc(Mid(Header,2,1))\2 Mod 4) 'Layer
		Case 3	'Layer 1
			BitRate=(Asc(Mid(Header,3,1))\16)*32	'Asc(Mid(Header,3,1))\16
		Case 2	'Layer 2
			BitRate=Array(0,32,48,56,64,80,96,112,128,160,192,224,256,320,384)(Asc(Mid(Header,3,1))\16)
		Case 1	'Layer 3
			If (Asc(Mid(Header,2,1))\8 Mod 2)=0 Then	'MPEG 2
				BitRate=Array(0,8,16,24,32,64,80,56,64,128,160,112,128,256,320)(Asc(Mid(Header,3,1))\16)
			Else	'MPEG 1
				BitRate=Array(0,32,40,48,56,64,80,96,112,128,160,192,224,256,320)(Asc(Mid(Header,3,1))\16)
			End If
		Case Else
			BitRate=0
		End Select
	End Property

	Property Get Frequency	'in Hz
		If Not Test_Path Then Exit Property
		If (Asc(Mid(Header,2,1))\8 Mod 2)=0 Then	'MPEG2
			Frequency=Array(22050,24000,16000)((Asc(Mid(Header,3,1)) Mod 16)\4)
		Else	'MPEG1
			Frequency=Array(44100,48000,32000)((Asc(Mid(Header,3,1)) Mod 16)\4)
		End If
	End Property

	Property Get Pad	'Frame padded with an extra byte
		If Not Test_Path Then Exit Property
		Pad=(Asc(Mid(Header,3,1)) Mod 4)\2
	End Property

	Property Get Priv	'Private
		If Not Test_Path Then Exit Property
		Priv=Asc(Mid(Header,3,1)) Mod 2
	End Property

	Property Get Mode
		If Not Test_Path Then Exit Property
		Mode=Array("Stereo","Joint Stereo","Dual Channel","Mono")(Asc(Right(Header,1))\64)
	End Property

	Property Get ModeExtension
		If Not Test_Path Then Exit Property
		ModeExtension=(Asc(Right(Header,1))\16) Mod 4
	End Property

	Property Get Copyright
		If Not Test_Path Then Exit Property
		'If value=1 then it's illegal to copy the contents
		CopyRight=(Asc(Right(Header,1))Mod 16)\8
	End Property

	Property Get Home
		If Not Test_Path Then Exit Property
		'If set to 1 then file located on its original media
		Home=(Asc(Right(Header,1))Mod 8)\4
	End Property

	Property Get Emphasis
		If Not Test_Path Then Exit Property
		Emphasis=Array("none","50/15ms","","CCITT j.17")(Asc(Right(Header,1))Mod 4)
	End Property

	Property Get FrameSize
		If Not Test_Path Then Exit Property
		FrameSize=Fix(144*BitRate*1000/Frequency)+Pad
	End Property


	'--- id3v1 ---
	' Not in all mp3 files. Check the ValidTag value

	Property Get ValidTag	'Return True if it contains an id3v1 Tag
		If Not Test_Path Then Exit Property
		Read_id3v1
		ValidTag=(Left(id3v1,3)="TAG")
	End Property
	Property Get Title
		If Not Test_Path Then Exit Property
		Read_id3v1
		Title=sz2str(Mid(id3v1,4,30))
	End Property
	Property Get Artist
		If Not Test_Path Then Exit Property
		Read_id3v1
		Artist=sz2str(Mid(id3v1,34,30))
	End Property
	Property Get Album
		If Not Test_Path Then Exit Property
		Read_id3v1
		Album=sz2str(Mid(id3v1,64,30))
	End Property
	Property Get Year
		If Not Test_Path Then Exit Property
		Read_id3v1
		Year=Mid(id3v1,94,4)
	End Property
	Property Get Comment
		If Not Test_Path Then Exit Property
		Read_id3v1
		Comment=sz2str(Mid(id3v1,98,30))
	End Property
	Property Get Track
		If Not Test_Path Then Exit Property
		Read_id3v1
		Track=asc(Mid(id3v1,127,1))
	End Property
	Property Get Genre
		Dim x
		If Not Test_Path Then Exit Property
		Read_id3v1
		x=Asc(Right(id3v1,1))
			Genre=Array("Blues","Classic Rock","Country","Dance","Disco","Funk","Grunge","Hip-Hop","Jazz","Metal", _
			"New Age","Oldies","Other","Pop","R&B","Rap","Reggae","Rock","Techno","Industrial","Alternative", _
			"Ska","Death Metal","Pranks","Soundtrack","Euro-Techno","Ambient","Trip-Hop","Vocal","Jazz+Funk", _
			"Fusion","Trance","Classical","Instrumental","Acid","House","Game","Sound Clip","Gospel","Noise", _
			"AlternRock","Bass","Soul","Punk","Space","Meditative","Instrumental Pop","Instrumental Rock","Ethnic", _
			"Gothic","Darkwave","Techno-Industrial","Electronic","Pop-Folk","Eurodance","Dream","Southern Rock", _
			"Comedy","Cult","Gangsta","Top 40","Christian Rap","Pop/Funk","Jungle","Native American","Cabaret", _
			"New Wave","Psychadelic","Rave","Showtunes","Trailer","Lo-Fi","Tribal","Acid Punk","Acid Jazz", _
			"Polka","Retro","Musical","Rock & Roll","Hard Rock","Folk","Folk/Rock","National Folk","Swing", _
			"Fast-Fusion","Bebob","Latin","Revival","Celtic","Blue Grass","Avantegarde","Gothic Rock", _
			"Progressive Rock","Psychedelic Rock","Symphonic Rock","Slow Rock","Big Band","Chorus","Easy Listening", _
			"Acoustic","Humour","Speech","Chanson","Opera","Chamber Music","Sonata","Symphony","Booty Bass", _
			"Primus","Porn Groove","Satire","Slow Jam","Club","Tango","Samba","Folklore","Ballad","power Ballad", _
			"Rhythmic Soul","Freestyle","Duet","Punk Rock","Drum Solo","A Capella","Euro-House","Dance Hall", _
			"Goa","Drum & Bass","Club-House","Hardcore","Terror","indie","Brit Pop","Negerpunk","Polsk Punk", _
			"Beat","Christian Gangsta Rap","Heavy Metal","Black Metal","Crossover","Comteporary Christian", _
			"Christian Rock","Merengue","Salsa","Trash Metal","Anime","JPop","Synth Pop")(x)
	End Property

	Property Get GenreNum
		If Not Test_Path Then Exit Property
		Read_id3v1
		GenreNum=Asc(Right(id3v1,1))
	End Property

	Property Let machin(truc)
	End Property
End Class


Dim x 
set x=new mp3
x.FileName="x:\yourfile.mp3"
wscript.echo "Sync=" & x.Sync & vbCrLf & "Layer=" & x.Layer & vbCrLf & "ID=" & x.id & vbCrLf _
	& "Prot=" & x.prot & vbCrLf & "BitRate=" & x.BitRate & vbCrLf & "frequency:" & x.Frequency & vbCrLf _
	& "Pad=" & x.pad & vbCrLf & "Priv=" & x.Priv & vbCrLf & "Mode=" & x.Mode & vbCrLf & "ModeExtension=" & x.ModeExtension & vbCrLF _
	& "copyRight=" & x.Copyright & vbCrLf & "Home=" & x.Home & vbCrLf & "Emphasis=" & x.Emphasis & vbCrLf & "FrameSize=" & x.FrameSize
If x.ValidTag Then
	WScript.Echo "Title=" & x.Title & vbCrLF & "artist:" & x.artist & vbCrLf & "album:" & x.album & vbCrLf _
	& "Year:" & x.year & vbCrLf & "Comment : " & x.comment & vbCrLf & "Track # : " & x.track & vbCrLf & "Genre:" & x.genre & vbCrLf & "Genre Number:" & x.GenreNum
Else
	WScript.Echo "No info (id3v1) in this file"
End If
Set x=Nothing