>>> Tim Hammerquist 15-Jun-05 19:59 >>>
>
> I don't have a 3.7 box handy to check this on, so if it works in 3.7,
> ignore this output:

That's the important part, isn't it?  file(1) gets updated from time
to time :)  The OP didn't specify which version of OpenBSD.


    carbon $ dmesg | head -2
    OpenBSD 3.7 (GENERIC) #50: Sun Mar 20 00:01:57 MST 2005
        [EMAIL PROTECTED]:/usr/src/sys/arch/i386/compile/GENERIC

    carbon $ mp3info ~/foo.mp3
    /home/tom/foo.mp3 does not have an ID3 1.x tag.

    carbon $ file ~/foo.mp3   
    /home/tom/foo.mp3: MP3, 128 kBits, 44.1 kHz, JStereo


A perusal of magic(5) shows that it's the beginning of the MP3 frame
info that is examined (the frame sync, the MPEG audio version ID, etc):

    # MPEG 1.0 Layer 3
    0       beshort&0xfffe  =0xfffa         \bMP3
    >2      byte&0xf0       =0x10           \b,  32 kBits
    >2      byte&0xf0       =0x20           \b,  40 kBits
    :
    :
    >2      byte&0xf0       =0xE0           \b, 320 kBits
    # freq
    >2      byte&0x0C       =0x00           \b, 44.1 kHz
    >2      byte&0x0C       =0x04           \b, 48 kHz
    >2      byte&0x0C       =0x08           \b, 32 kHz


Thanks

Tom

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