[vorbis] just an idea about quality evaluation

[gtgbr at gmx.net]

Daniel Schregenberger wrote:
> > If you're not comparing how the codecs sound (which most people are
> > interested in), but what data they throw away, this test is very
> > valuable.
> So I was essentially right: it may be a help to choose a decent quality setting
> for converting mp3s to ogg. (I mean: I can't hear a difference between a
> 256k_mp3-->q10 and a 256k_mp3-->q9; maybe looking at how much data has been
> discarded helps me choose a quality)

Uh ... so you're telling that you make your MP3 files bigger by
converting them to .ogg @ -q 9 or 10 ??

That's the point of doing that again? Unless you stream in Ogg Vorbis at
such insane bitrates, which I find unlikely, you're just wasting space
and quality. Whatever little amount of percievable information Vorbis
throws away at -q 10, it's still that little info *plus* whatever MP3
threw away, compared to the original. I also don't know of any player
that supports .ogg but NOT .mp3, so why re-encode?

Rip again, from CD to .ogg, and you'll be happy with -q 6, 5 or 4, or
maybe even lower. There's no reason to listen to MP3 quality in .ogg
files.

And no, you're not right - everybody just said that this kind of
comparison is completely useless for quality considerations ... I gotta
know, I asked that question somewhen between 1 to 2 years ago on #vorbis
and got the same answer - even from Monty himself. :P

<p>Moritz
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