[vorbis] reencoding OGG Vorbis

[Kristoff Bonne]

Greetings,

On Wed, 21 Feb 2001, Oddsock wrote:
>>>>As I heard, and I am pretty sure that it's true, MP3 files can be
>>>>decoded and reencoded unlimited times without further quality loss (of
>>>>course the same encoder with the same preferences has to be used all the
>>>>time). Is this also possible with .OGG?
>> Maybe I'm missing the point, but why on earth would you WANT to do
>> something like that?  I've heard of people (usually uninformed people)
>> decoding a song from one format and then trying to encode it in
another,
>> but just doing encode-decode cycles in the same format?  Even if you
>> could do such a thing without quality degradation, why do it in the
>> first place?

> I've done this for a few things...I've got a Memorex MP3 CD player which 
> only plays MP3s sampled at 44kHz...Much of my collection of Old Time Radio 
> shows are 32/22, and would not play on the player at all....by using LAME, 
> I could upsample them to 32/44...this goes through a decode/encode step to 
> do it...the resultant output was indistinguishable at that bitrate 
> (granted, not the highest quality)...Either way, there are  some uses for 
> reencoding into the same format....

Another possible application is a radio-station I know, who broadcasts to
the internet in mp3.

They get their music (usually mp3-files taken from the net) from all-kind
of different source, some encoded at 192 Kbps, some at 160 Kbps and still
other at 128 Kbps.

They have noticed that there are a lot of problems with mp3-players, when
(first) broadcasting at bitrate x and (later) at to bitrate y. Apparently,
a lot of mp3 players don't really like to change the bitrate in the middle
of a stream.

So, they decided to 're-rate' everything at 192 Kbps. (Althou I don't know
if they actually had to decode and re-encode they music to and from PCM).

Cheerio! Kr. Bonne.

-- 
KB905-RIPE                                       Belgacom  IP networking
(c=be,a=rtt,p=belgacomgroup,s=Bonne,g=Kristoff)  Internet, IP and IP/VPN
kristoff.bonne at skypro.be                         Faxbox :  +32 2 2435122

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.