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Subject: Re: VBR Files Query
From: Chris Holt (amiga2k_at_cox.net)
Date: 2002-11-27


----- Original Message -----
From: <JJTye_at_aol.com>
To: <rockbox_at_cool.haxx.se>
Sent: Tuesday, November 26, 2002 4:31 PM
Subject: VBR Files Query

> Dear Rockbox
>
> Just a slight quibble, when playing some highly compressed VBR files the
time
> duration of the song is displayed incorrectly. Is this normal? Not a big
> issue since I only compress at 192kbs (pointless going above 192kbs). And
is
> there really a difference between codecs such as Lame, Blade, Fraunhofer
etc?
> After all, lets say we make a 192Kbs MP3 file of the same song using the 3
> codecs, no matter what codec is used its gonna contain the same number of
1's
> and 0's! (And therefore all 3 variants should sound the same)

There are various techniques for removing information from an audio file to
compress it. All encoders are NOT equal, not even close. There are
variations in quality, speed of encoding and capabilities among all the
encoders out there. There is ongoing discussion and debate all over the
internet about the quality and efficiency of various encoders.

This could explain the VBR issue, as there is seek information placed into
VBR files by some encoders that allows for accurate time display on players
that support it. I can't swear to this, as I have not fully researched VBR
seek information, but I'm sure someone here can help with that info.

> Would Archos be unhappy that we are no longer using their firmware since
the
> Rockbox firmware is light-years ahead? Just hope Archos don't threaten us
> with legal action........

Rockbox was reverse engineered AFAIK, no one has any legal grounds to go
after them, especially since they do not charge us for the privledge of
using rockbox. :)

> To that very nice man who suggested to me wire up a real swing-needle VU
> meter into the Archos, I can go one step further :-) Find a chip that can
> handle other codecs such as WMA, AAC etc, rip out the old Archos chip and
> solder in the new one! (Havent tried it but may do in the future :-)....
No,
> Ill go another step further. Ill get one of those colour LCDs used in mini
> TVs and digital camcorders so I can hook up a DVD player to the digital IN
on
> my Archos and rip DVDs to the hard drive! (That was a joke but we can all
> dream :-) )

I saw some mini neon tubing at WalMart today, with a step up transformer and
some really high capacity batteries, we could...

Nevermind. :)

> All the best Rockboxers
>
> JTCP.

Chris



Page was last modified "Jan 10 2012" The Rockbox Crew
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