Working with mp3

Ok Here goes:

I have made a simple mp3 player with the Windows Media Player control. I would like to know

1. How to determine its bitrate, and

2. How to get its length in min/sec

I have done the second by loading it into the med player and getting the filename's duration, but it was very slow. Anyone know how to do either of these? Thanks

the www.vbweb.co.uk have a great mp3 tut.
u'll find their the answer to your question

regards

[steve(again)]

Hi, working on something myself,
as an example 128kbps 44100 divide filesize by 16000 time in seconds.

Sample Rate
44100
160kbps Stereo Mp1.0 L3 VBR frame261bytes
160kbps Mp1 L3 /20000
128kbps Stereo Mp1.0 L3 /16000 frame208*2
128kbps JS Mp1 /16000 frame208*2
112kbps JS Mp1.0 L3 /14000 frame182*2
96kbps JS Mp1.0 L3 /12000 frame156
32kbps Mono Mp1.0 L2 /4000
48000
32000
64kbps Mono Mp1.0 L3 /8000 frame144
22050
64kbps JS M2.0 L3 /8000
56kbps JS M2 L3 /
40kbps JS M2.0 L3 /5000 frame130
32kbps Mono M2.0 L3 /4000 frame104
24000
16000
24kbps JS M2.0 L3 /8000
11025
16kbps Mono M2.5 L3 /2000 frame104
12000
8000

trying to find another doc also

[Jop]

Here's a module I wrote some time ago...
it's not finished yet, do it yourself

Option Explicit
'MP3 info module made by Jop de Klein.

Public Type MP3Info
        'Header info
        Bitrate As String
        Layer As String
        MPEGv As String
        Emphasis As String
        Private As Boolean
        Original As Boolean
        CopyRighted As Boolean
        Protected As Boolean

        'ID3 Tag
        IsValidTag As Boolean
        Artist As String * 30
        Album As String * 30
        Title As String * 30
        Year As String * 4
        Comment As String * 30
        Genre As String * 1
End Type


Public Function GetMp3Info(f As String) As MP3Info
Dim fn%, tmp() As Byte, Bitrate&, Tag$, Title$, mp3 As MP3Info, nr&
fn = FreeFile  'sets a free file slot for the fileopening.
ReDim tmp(3) 'Redim the byte array (4 bytes = 32 bits) so we can put the header in it

Open f For Binary As #fn
    Get #fn, , tmp 'this is for the header, the first 4 bytes (32 bits)
Tag = Space(128) 'Fill the string with spaces so there's enough room to put the ID3Tag in.
    Get #fn, LOF(fn) - 127, Tag 'this is to get the id3 tag, the last 128 bytes.
Close #fn

With mp3
    'Get the mp3 information
    
'Ok let me explain you something, it MIGHT confuse you 
'to take bits out of a byte, we use AND & then 2 ^ n
'where n is the number of the bit
'so let's say we want the 20th bit
'we have 32 bits in the byte array (called tmp), so 3 * 8 = 24
'so we take the third byte, that's tmp(2), cause arrays start
'from 0.
'Remember we use AND to take the bits out, and we want the
'4th bit out of the third byte.
'We now do tmp(2) AND 2 ^ 4
'          ^byte          ^bit

'For speed and coolness improvement we use HEXIDECIMAL codes 
'Just to show how cool we are ok? 
'You don't need to know what's all this, read more about
'HEXIDECIMAL stuff on the internet
'When we want to take the 20th bit I would do
'tmp(2) AND 2 ^ 4, and with hex that would be
'tmp(2) AND &H10

'If you really need the Hex values try (IN VB)
'MSGBOX HEX(2 ^ n), where n = the number of the bit.
'Like MSGBOX HEX(2 ^ 4) would result 10
'so you would write in VB
'tmp(2) AND &H10, where H means hex, to notify VB it's
'not a decimal nr.


'These are booleans (from the header)
    .Original = CBool(tmp(3) And &H40) 'this is bit 30 (bit 6 of the 4th byte)
    .CopyRighted = CBool(tmp(3) And &H20) 'this is bit 29 (bit 5 of the 4th byte)
    .Private = CBool(tmp(2) And &H100) 'this is bit 24 (bit 8 of the 3th byte)
    .Protected = CBool(tmp(1) And &H100) 'this is bit 16 (bit 8 of the 2nd byte)
    
'Does not work yet (header info), I'll fix it later 
 '  .Bitrate = (tmp(2) \ &H10) 
    .Bitrate = (tmp(2) And &H1F0) \ 16) 'bit 20 - 23 (bit 4 to 8 from the 3nd byte)
    .Layer = (tmp(1) And &H180) \ 128 'bit 14 - 15 (7 and 8 from the 2nd byte)
    .MPEGv = (tmp(1) And &H10) 'bit 12 - 13
    .Emphasis = (tmp(0) And &H3) \ 1 'bit 1 - 2 from the first byte

'from now on, it works again 
'this is for the ID3tags
    .IsValidTag = (Trim(Mid(Tag, 1, 3) = "TAG")) 'sets a boolean to see if tag exists

If .IsValidTag Then 'only continue if the tag is valid, to avoid errors
     .Title = Trim(Mid(Tag, 4, 30))
      .Artist = Trim(Mid(Tag, 34, 30))
       .Album = Trim(Mid(Tag, 64, 30))
      .Year = Trim(Mid(Tag, 94, 4))
     .Comment = Trim(Mid(Tag, 98, 30))
    .Genre = asc(Trim(Mid(Tag, 128, 1)))
End If

End With
GetMp3Info = mp3
End Function

Well, the part from Bitrate to the Emphasis doesn't work yet (I have no time (well I don't wanna right now) to fix it, do so if you like)

the ID3 part is working so that'll get you started, also, the Genre has to be converted with a table too, haven't implemented it *yet*, do so if you need it.

here's how you would call the sub

Private Sub Form_Load()
Dim mp3 As Mp3Info
mp3 = GetMp3Info("MYMP3FILE")
MsgBox mp3.Album 'to display the album of the mp3file.
End Sub

Have Fun!

thanks eevryone, ill check it out