ID3 Info code that actually works

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Aug 30th, 2002, 06:46 AM
Arc

ID3 Info code that actually works

Hi all. I have this ID3 code that gets the Khz, Kbps, and Stereo/Mono among other info. But it almost always returns incorrect info. I really dont know where it gets these numbers from(just makes them up i think).

Does anyone have any ID3 code that really works?

Thanks!;) :D :)
Aug 30th, 2002, 11:05 PM
Arc

Anyone know?
Aug 31st, 2002, 03:50 AM
mr_metal_hed

The mp3 information you are after isn't stored in the id3 tag. You have to get information from the mpeg frame and calculate some of it. I think variable bitrates may be causing some calculations to come out wrong, or at least appear wrong. I *had* a module that would get what you are after. I'll see if I can locate it.
Aug 31st, 2002, 03:59 AM
mr_metal_hed

1 Attachment(s)

Here's the one I use. I hope it's not the same as the one you are using. :D Good luck.
Aug 31st, 2002, 12:13 PM
Arc

Actually it's not the same bas. But it does give the exact same inccorect bitrate and Freq info. :(

Anyone have code that actually works?
Aug 31st, 2002, 12:45 PM
mr_metal_hed

Are these variable bitrate mp3's? Or do you get bad results for all of your files?
Aug 31st, 2002, 09:42 PM
Arc

I have no idea if they are variable bitrate.

All i know is, the mp3's i am testing the code on are mp3's that i made and recorded and converted. So i know exactly what the bitrate and Freq is. I then test it in Winamp to make double sure. Winamp always returns the correct info.... These Bas's almost never do.

For instance, i have one mp3 that was converted to mp3 at 32kbps/32000Khz and the Bas returns 256Kbps/64000Khz...
Aug 31st, 2002, 10:06 PM
Mc Brain

The BitRate depends on a table. If you have the table information wrong... then, it will always answer a wrong bitrate.

VB Code:

'BitRate
            '           MPEG-1,     MPEG-1,     MPEG-1,     MPEG-2,     MPEG-2,     MPEG-2,
            'Value      layer I     layer II    layer III   layer I     layer II    Layer III
            '0 0 0 0
            '0 0 0 1    32          32          32          32          32          8
            '0 0 1 0    64          48          40          64          48          16
            '0 0 1 1    96          56          48          96          56          24
            '0 1 0 0    128         64          56          128         64          32
            '0 1 0 1    160         80          64          160         80          64
            '0 1 1 0    192         96          80          192         96          80
            '0 1 1 1    224         112         96          224         112         56
            '1 0 0 0    256         128         112         256         128         64
            '1 0 0 1    288         160         128         288         160         128
            '1 0 1 0    320         192         160         320         192         160
            '1 0 1 1    352         224         192         352         224         112
            '1 1 0 0    384         256         224         384         256         128
            '1 1 0 1    416         320         256         416         320         256
            '1 1 1 0    448         384         320         448         384         320
            '1 1 1 1

Aug 31st, 2002, 10:58 PM
Arc

yah, this bas has the right tables... it has all those values, but for some reason its picking the wrong ones..
Aug 31st, 2002, 11:06 PM
Mc Brain

I can't test it now because I don't have any MP3 on this machine.
Aug 31st, 2002, 11:08 PM
Mc Brain

Anyway... I've got it working already. Have a look at this:

http://www.vbforums.com/showthread.p...hlight=bitrate
Aug 31st, 2002, 11:39 PM
DiGiTaIErRoR

You forget. Some mp3s don't even have ID tags.
Aug 31st, 2002, 11:46 PM
Mc Brain

Quote:

Originally posted by DiGiTaIErRoR
You forget. Some mp3s don't even have ID tags.

it doesn't mind at all.... the header is not saved in the ID tags.
Sep 1st, 2002, 10:25 AM
Arc

Cool Mcbrain. I could see form the Final Pic in that thread that you figured it out. But you never gave the final code you used to make it work.

Any chance i could snag that from you :)?

Would really appreciate it :D Thanks.
Sep 1st, 2002, 04:26 PM
Mc Brain

Quote:

Originally posted by Arc
Cool Mcbrain. I could see form the Final Pic in that thread that you figured it out. But you never gave the final code you used to make it work.

Any chance i could snag that from you :)?

Would really appreciate it :D Thanks.

Yes, I did.. it's all in there. Just read the thread. All you have to do is copy the code, and Bazza's suggestion.

This is the code:

http://www.vbforums.com/showthread.p...450#post994450

And you have to change the line: Get #fn, 11 + Len(Tag2), sHeader taking into account Bazza's code:

VB Code:

For lCount = 1 To 5000
        Get #1, lCount, bHead(0)
        If bHead(0) = 255 Then
            Get #1, lCount + 1, bHead(1)
            If bHead(1) = 250 Or bHead(1) = 251 Then
                FirstFrame = lCount
                Exit For
            End If
        End If
    Next lCount

Ok, i am trying to follow you here. I see the 2 peices of code but i am not sure how to innertwine them. Since i didnt write the code and havent done much research into decoding MP3 headers i'm not sure exactly what is going on.

But if i had to guess i would say that where you have the
VB Code:
Get #fn, 11 + Len(Tag2), sHeader
 
 
I would put
 
For lCount = 1 To 5000
        Get #1, lCount, sHeader(0)
        If sHeader(0) = 255 Then
            Get #1, lCount + 1, sHeader(1)
            If sHeader(1) = 250 Or sHeader(1) = 251 Then
                FirstFrame = lCount
                Exit For
            End If
        End If
    Next lCount
Usualy i am real good at interpretting other peoples code.. but in this case i'm a bit lost.....:(

Sep 1st, 2002, 09:49 PM
Arc

Hmm then i was thinking it was that the Bhead() array was trhe Bitrate array, but your Bitrate array id multi dimentional so that can't be it....

Here are the changes:

VB Code:

Dim bHead(1) As String * 1
        Dim lCount As Integer
        For lCount = 1 To 5000
            Get #fn, lCount, bHead(0)
            If Asc(bHead(0)) = 255 Then
                Get #fn, lCount + 1, bHead(1)
                If Asc(bHead(1)) = 250 Or Asc(bHead(1)) = 251 Then
                    lngHeaderPosition = lCount
                    Exit For
                End If
            End If
        Next lCount
 
        Get #fn, lngHeaderPosition, sHeader

I'm sorry man, but those are the chnages to what? That code wasnt in your original code... and i have know idea where that is suppost to go. Do i take out all the Bitrate() Array code? Do i sqeeze it in the middle there somewhere? At the beggining? At the end? I have no idea where that is supposed to go.

I've tried it several ways and i've gotten several different results...none of which have been accurate..

This is what i currently have...

VB Code:

Public Type MP3Header
    MP3Length As Long
    Position As Long
    Duration As Integer
    ID As String
    Layer As String
    SampleRate As String
    Mode As String
    Emphasis As String
    Padding As Boolean
    FrameSize As Long
    FrameCount As Long
    CopyRighted As Boolean
    Original As Boolean
    BitRate As String
    CRC As Boolean
End Type
 
 
Public Version As Byte
 
Public Sub ReadFile(strFilename As String, mHeader As MP3Header)
 
    Static BitRate(11 To 23, 1 To 14) As String
    Dim bHead(1) As String * 1
    Dim lCount As Integer
    Dim fn As Integer
    Dim lngHeaderPosition As Long
    Dim lngFilesize As Long
    Dim BitLine As Integer
    Dim i As Byte
    
    Dim Tag2 As String
    Dim TagSize As String * 4
    Dim ID3Tag As String * 3
    Dim sHeader As String * 4
    
If BitRate(11, 1) = "" Then
        BitRate(11, 1) = "32"
        BitRate(11, 2) = "64"
        BitRate(11, 3) = "96"
        BitRate(11, 4) = "128"
        BitRate(11, 5) = "160"
        BitRate(11, 6) = "192"
        BitRate(11, 7) = "224"
        BitRate(11, 8) = "256"
        BitRate(11, 9) = "288"
        BitRate(11, 10) = "320"
        BitRate(11, 11) = "352"
        BitRate(11, 12) = "384"
        BitRate(11, 13) = "416"
        BitRate(11, 14) = "448"
        BitRate(12, 1) = "32"
        BitRate(12, 2) = "48"
        BitRate(12, 3) = "56"
        BitRate(12, 4) = "64"
        BitRate(12, 5) = "80"
        BitRate(12, 6) = "96"
        BitRate(12, 7) = "112"
        BitRate(12, 8) = "128"
        BitRate(12, 9) = "160"
        BitRate(12, 10) = "192"
        BitRate(12, 11) = "224"
        BitRate(12, 12) = "256"
        BitRate(12, 13) = "320"
        BitRate(12, 14) = "384"
        BitRate(13, 1) = "32"
        BitRate(13, 2) = "40"
        BitRate(13, 3) = "48"
        BitRate(13, 4) = "56"
        BitRate(13, 5) = "64"
        BitRate(13, 6) = "80"
        BitRate(13, 7) = "96"
        BitRate(13, 8) = "112"
        BitRate(13, 9) = "128"
        BitRate(13, 10) = "160"
        BitRate(13, 11) = "192"
        BitRate(13, 12) = "224"
        BitRate(13, 13) = "256"
        BitRate(13, 14) = "320"
        BitRate(21, 1) = "32"
        BitRate(21, 2) = "64"
        BitRate(21, 3) = "96"
        BitRate(21, 4) = "128"
        BitRate(21, 5) = "160"
        BitRate(21, 6) = "192"
        BitRate(21, 7) = "224"
        BitRate(21, 8) = "256"
        BitRate(21, 9) = "288"
        BitRate(21, 10) = "320"
        BitRate(21, 11) = "352"
        BitRate(21, 12) = "384"
        BitRate(21, 13) = "416"
        BitRate(21, 14) = "448"
        BitRate(22, 1) = "32"
        BitRate(22, 2) = "48"
        BitRate(22, 3) = "56"
        BitRate(22, 4) = "64"
        BitRate(22, 5) = "80"
        BitRate(22, 6) = "96"
        BitRate(22, 7) = "112"
        BitRate(22, 8) = "128"
        BitRate(22, 9) = "160"
        BitRate(22, 10) = "192"
        BitRate(22, 11) = "224"
        BitRate(22, 12) = "256"
        BitRate(22, 13) = "320"
        BitRate(22, 14) = "384"
        BitRate(23, 1) = "8"
        BitRate(23, 2) = "16"
        BitRate(23, 3) = "24"
        BitRate(23, 4) = "32"
        BitRate(23, 5) = "64"
        BitRate(23, 6) = "80"
        BitRate(23, 7) = "56"
        BitRate(23, 8) = "64"
        BitRate(23, 9) = "128"
        BitRate(23, 10) = "160"
        BitRate(23, 11) = "112"
        BitRate(23, 12) = "128"
        BitRate(23, 13) = "256"
        BitRate(23, 14) = "320"
    End If
  
    
 
    fn = FreeFile
    Open strFilename For Binary As #1
    lngFilesize = LOF(fn)
          
    Get #fn, 1, ID3Tag
 
 
    If ID3Tag = "ID3" Then
        lngHeaderPosition = 1
        Dim R As Long
        Get #fn, 4, Version
        Get #fn, 7, TagSize
 
        R = CVL(TagSize, 128)
        If R > lngFilesize Or R > 2147483647 Then
            Exit Sub
        End If
        Tag2 = Space$(R)
        Get #fn, 11, Tag2
        lngHeaderPosition = R + 11
    End If
 
 
'#########################
'%%%%%%%%%%%%%%%%%%%
' I put the new code here
        For lCount = 1 To 5000
            Get #fn, lCount, bHead(0)
            If Asc(bHead(0)) = 255 Then
                Get #fn, lCount + 1, bHead(1)
                If Asc(bHead(1)) = 250 Or Asc(bHead(1)) = 251 Then
                    lngHeaderPosition = lCount
                    Exit For
                End If
            End If
        Next lCount
 
        Get #fn, lngHeaderPosition, sHeader
 
'#########################
'%%%%%%%%%%%%%%%%%%%
 
        
 
        
        With mHeader
            .MP3Length = FileLen(strFilename)
            .Position = 11 + Len(Tag2)
            
            '*** Second Byte ***
            sHeader = Mid$(sHeader, 2)
            
            'MPEG Audio version ID
            '00 - MPEG Version 2.5
            '01 - reserved
            '10 - MPEG Version 2 (ISO/IEC 13818-3)
            '11 - MPEG Version 1 (ISO/IEC 11172-3)
            i = (Asc(sHeader) And 24) / 8
            .ID = IIf(i = 0, "MPEG-2.5", IIf(i = 1, "reserved", _
                 IIf(i = 2, "MPEG-2", "MPEG-1")))
            BitLine = IIf(i = 3, 10, 20)
            
            'Layer description
            '0 0 Not defined
            '0 1 Layer III
            '1 0 Layer II
            '1 1 Layer I
            i = (Asc(sHeader) And 6) / 2
            .Layer = IIf(i = 0, "Not defined", IIf(i = 1, "Layer 3", _
                 IIf(i = 2, "Layer 2", "Layer 1")))
            BitLine = BitLine + (4 - i)
            
            'CRC
            '0 = No
            '1 = Yes
            i = (Asc(sHeader) And 1)
            .CRC = Not (-i)
            
            ' *** Third Byte ***
            sHeader = Mid$(sHeader, 2)
            
             i = (Asc(sHeader) And 240) / 16
            On Error Resume Next
            .BitRate = "Not defined"
            .BitRate = BitRate(BitLine, i) & "kbit"
         
            
            'Frequency
            'value MPEG-1 MPEG-2
            '0 0 44100 Hz 22050 Hz
            '0 1 48000 Hz 24000 Hz
            '1 0 32000 Hz 16000 Hz
            '1 1
            i = (Asc(sHeader) And 12) / 4
            If .ID = "MPEG-1" Then
                .SampleRate = IIf(i = 0, "44100 Hz", _
                     IIf(i = 1, "48000 Hz", "32000 Hz"))
            Else
                .SampleRate = IIf(i = 0, "22050 Hz", _
                     IIf(i = 1, "24000 Hz", "16000 Hz"))
            End If
            
            'Padding Bit
            '0 - frame is not padded
            '1 - frame is padded with one extra slot
            i = (Asc(sHeader) And 2) / 2
            .Padding = i
            
            ' *** Forth Byte ***
            sHeader = Mid$(sHeader, 2)
            
            'Mode value mode
            '0 0 Stereo
            '0 1 Joint stereo
            '1 0 Dual channel
            '1 1 Mono
            i = (Asc(sHeader) And 192) / 64
            .Mode = IIf(i = 0, "Stereo", IIf(i = 1, "Joint Stereo", _
                 IIf(i = 2, "Dual channel", "Mono")))
 
            'Copyright
            '0 - Audio is not copyrighted
            '1 - Audio is copyrighted
            i = (Asc(sHeader) And 8) / 8
            .CopyRighted = i
            
            'Original
            '0 - Copy of original media
            '1 - Original media
            i = (Asc(sHeader) And 4) / 4
            .Original = i
            
            'Emphasis value Emphasis method
            '0 0 none
            '0 1 50/15ms
            '1 0
            '1 1 CCITT j.17
            i = (Asc(sHeader) And 3)
            .Emphasis = IIf(i = 0, "None", IIf(i = 1, "50/15ms", _
                 IIf(i = 2, "reserved", "CCITT j.17")))
            
            .FrameSize = IIf(.Layer = "Layer 1", _
               12 * Val(.BitRate) * 1000 \ Val(.SampleRate) - .Padding, _
               144 * Val(.BitRate) * 1000 \ Val(.SampleRate) - .Padding)
               
            .FrameCount = (.MP3Length - .Position - 4) \ .FrameSize
            .Duration = ((.MP3Length - .Position - 4) * 8 \ Val(.BitRate)) / 1000
        End With
        Close
End Sub
 
Public Function CVL(ByVal Cadena As String, Optional Valor As Integer = 256) _
  As Long
    Dim i As Integer
    CVL = 0
    
    For i = 3 To 0 Step -1
        CVL = CVL + (Valor ^ i) * Asc(Cadena)
        Cadena = Mid$(Cadena, 2)
    Next i
    
End Function

Thanks! For your help:D

Sep 1st, 2002, 11:47 PM
Mc Brain

That's exactly where it should be. What's the problem with the code as it is?
Sep 2nd, 2002, 12:03 AM
Arc

Well im not getting any errors, its just returning bogus info.

Its saying this mp3 is at 256Kbps and 64Hz when in reality it is 40Kbps and 22Khz.
Sep 2nd, 2002, 12:11 AM
Mc Brain

Are all the rest values OK? It seems that the BitLine is 13, and the "i" = 13 when it should be 2. Can you debug it and see what's going on with the values....
Sep 2nd, 2002, 12:40 AM
Arc

Bitline=13
i =1

All the info that is being returned is way off. Its saying the Lenght is 24secs when its really 154secs. Its saying its mono when its stereo etc...

I'm not sure what else you need me to check.
Sep 2nd, 2002, 06:13 AM
Mc Brain

(13, 1) = 32 not 256. What's what you're getting??

Anyway... Most probable is that thhçe code is checking wherever but where it should. Check if the Header starts at the same position as it should.... if it's not, that's the cause.
Sep 2nd, 2002, 09:03 AM
Arc

Your code is saying Header found at 11 bytes..winamp is saying it was found at 0 bytes
Sep 2nd, 2002, 02:48 PM
Mc Brain

Check the value of the lngHeaderPosition variable.
Sep 2nd, 2002, 08:50 PM
Arc

lngHeaderPosition =3773

Ok... I've found that there are some differences with the actual code. Check what happens with this:

VB Code:

Dim bHead(1) As String * 1
        Dim lCount As Integer
        For lCount = 1 To 5000
            Get #fn, lCount, bHead(0)
            If Asc(bHead(0)) = 255 Then
                Get #fn, lCount + 1, bHead(1)
                If Asc(bHead(1)) = 250 Or Asc(bHead(1)) = 251 Then
                    lngHeaderPosition = lCount
                    Exit For
                End If
            End If
        Next lCount
 
        Get #fn, lngHeaderPosition, sHeader
        
        With mHeader
            .MP3Length = FileLen(strFilename)
            .Position = lngHeaderPosition - 1
            
            '*** Second Byte ***
            sHeader = Mid$(sHeader, 2)
            
            'MPEG Audio version ID
            '00 - MPEG Version 2.5
            '01 - reserved
            '10 - MPEG Version 2 (ISO/IEC 13818-3)
            '11 - MPEG Version 1 (ISO/IEC 11172-3)
            i = (Asc(sHeader) And 24) / 8
            .ID = IIf(i = 0, "MPEG-2.5", IIf(i = 1, "reserved", IIf(i = 2, "MPEG-2", "MPEG-1")))
            BitLine = IIf(i = 3, 10, 20)
            
            'Layer description
            '0 0 Not defined
            '0 1 Layer III
            '1 0 Layer II
            '1 1 Layer I
            i = (Asc(sHeader) And 6) / 2
            .Layer = IIf(i = 0, "Not defined", IIf(i = 1, "Layer 3", IIf(i = 2, "Layer 2", "Layer 1")))
            BitLine = BitLine + (4 - i)
            
            'CRC
            '0 = No
            '1 = Yes
            i = (Asc(sHeader) And 1)
            .CRC = Not (-i)
            
            ' *** Third Byte ***
            sHeader = Mid$(sHeader, 2)
            
            'BitRate
            '           MPEG-1,     MPEG-1,     MPEG-1,     MPEG-2,     MPEG-2,     MPEG-2,
            'Value      layer I     layer II    layer III   layer I     layer II    Layer III
            '0 0 0 0
            '0 0 0 1    32          32          32          32          32          8
            '0 0 1 0    64          48          40          64          48          16
            '0 0 1 1    96          56          48          96          56          24
            '0 1 0 0    128         64          56          128         64          32
            '0 1 0 1    160         80          64          160         80          64
            '0 1 1 0    192         96          80          192         96          80
            '0 1 1 1    224         112         96          224         112         56
            '1 0 0 0    256         128         112         256         128         64
            '1 0 0 1    288         160         128         288         160         128
            '1 0 1 0    320         192         160         320         192         160
            '1 0 1 1    352         224         192         352         224         112
            '1 1 0 0    384         256         224         384         256         128
            '1 1 0 1    416         320         256         416         320         256
            '1 1 1 0    448         384         320         448         384         320
            '1 1 1 1
            i = (Asc(sHeader) And 240) / 16
            On Error Resume Next
            .BitRate = "Not defined"
            .BitRate = BitRate(BitLine, i) & "kbit"
            On Error GoTo errorhandler
            
            'Frequency
            'value MPEG-1 MPEG-2
            '0 0 44100 Hz 22050 Hz
            '0 1 48000 Hz 24000 Hz
            '1 0 32000 Hz 16000 Hz
            '1 1
            i = (Asc(sHeader) And 12) / 4
            If .ID = "MPEG-1" Then
                .SampleRate = IIf(i = 0, "44100 Hz", IIf(i = 1, "48000 Hz", "32000 Hz"))
            Else
                .SampleRate = IIf(i = 0, "22050 Hz", IIf(i = 1, "24000 Hz", "16000 Hz"))
            End If
            
            'Padding Bit
            '0 - frame is not padded
            '1 - frame is padded with one extra slot
            i = (Asc(sHeader) And 2) / 2
            .Padding = i
            
            ' *** Forth Byte ***
            sHeader = Mid$(sHeader, 2)
            
            'Mode value mode
            '0 0 Stereo
            '0 1 Joint stereo
            '1 0 Dual channel
            '1 1 Mono
            i = (Asc(sHeader) And 192) / 64
            .Mode = IIf(i = 0, "Stereo", IIf(i = 1, "Joint Stereo", IIf(i = 2, "Dual channel", "Mono")))
 
            'Copyright
            '0 - Audio is not copyrighted
            '1 - Audio is copyrighted
            i = (Asc(sHeader) And 8) / 8
            .CopyRighted = i
            
            'Original
            '0 - Copy of original media
            '1 - Original media
            i = (Asc(sHeader) And 4) / 4
            .Original = i
            
            'Emphasis value Emphasis method
            '0 0 none
            '0 1 50/15ms
            '1 0
            '1 1 CCITT j.17
            i = (Asc(sHeader) And 3)
            .Emphasis = IIf(i = 0, "None", IIf(i = 1, "50/15ms", IIf(i = 2, "reserved", "CCITT j.17")))
            
            
            .FrameSize = IIf(.Layer = "Layer 1", _
               12 * Val(.BitRate) * 1000 \ Val(.SampleRate) - .Padding, _
               144 * Val(.BitRate) * 1000 \ Val(.SampleRate) - .Padding)
               
            .FrameCount = (.MP3Length - .Position - 4) \ .FrameSize
            .Duration = ((.MP3Length - .Position - 4) * 8 \ Val(.BitRate)) / 1000
        End With
        Close

Sep 4th, 2002, 12:06 AM
Arc

Thanks alot for the help man. But it's still returning the same incorrect info. Except now where it says Header position found at.. it says 3772 instead of 11.

The lngHeaderPosition=3773

The first time Bitline is accesed it returns 10 and i returns 3

The second time Bitline = 13 and i = 1

I would be glad to send you the MP3 i'm using to get these results if you think it would figure this out.

Thnaks! :)
Sep 4th, 2002, 12:12 AM
Mc Brain

Send it to [email protected]
Sep 4th, 2002, 06:51 AM
Mc Brain

***?? That MP3 is not MPEG1- Layer 3 as all the MP3s. Maybe that's the reason why it's not reading it properly. :(

BTW, my "working code" doesn't work either.
Sep 5th, 2002, 06:26 AM
Mc Brain

Ok... I found a solution, and not so quite. In this page: http://www.mp3-tech.org/programmer/frame_header.html we can see that the table that I got from another place is wrong.

Even if I force to start reading the header at 0, it says it's MPEG2-Layer 3 but it says it's 64KB instead of 40KB. This page shows that (if it's correct), the proper value if 40KB (because the byte we get if 5). I'd think that the correct value is this one because Winamp says that also. ;)

Anyway, I'm still wondering why we got an MPEG2 MP3.