[vorbis] Ogg artifacts

[Jon Pomrenke]

I'm having some difficulty getting into Ogg. Being my first time encoding to
Ogg, I am left doubtful of the quality in reproduction. Hopefully, it is
merely something that I am doing.

My original intentions were to go through my CD collection and rip
everything out at 224kps VBR. I began with an album I was relatively
familiar with. I used FreeRip 2.53 initially, but found that I had
artifacts (clipping) in a couple places in a couple songs. Being suspicious
of the binaries being used, I switched over to tkcOggRipper and re-ripped
the album using the same settings (considerably faster rip for some
reason). Problem still existed, though less prominant. I now focused in on
one song.

What I got was a cleaner version of the file, but some artifacts still
existed (2 to be specific). I listened to the cd itself and found that
there was a hint of one of the artifacts in one position, but none that I
could hear in the other position. The CD I was ripping off of actually
happens to be a copy since my original CD became too scratched to use after
an unfortunate incident. Coincidentally, I do not know how good the
original CD was that this was taken from. Anyhow, I took that same song
again and ripped it using LAME 3.93.1 and EAC. EAC gives a track quality
report and on the track I kept trying to rip it reported 99.4% integrity,
however the end result is a perfectly encoded MP3 with no artifacts.

I used a different CD as a test platform, one that was near flawless, and I
have yet to detect any artifacts created. But being that ripping from
imperfect CDs is a fact of life, does this hinder Oggs application? Does
Ogg properly handle artifacts in the source, contrary to what I'm seeing? I
can understand clipping coming across when the source has difficulty
reading the song, but it is actually amplifying the artifact when LAME
doesn't even produce it. Is this normal to have artifacts compounded
through Ogg, but hidden through LAME? What does one do when they have an
imperfect CD that plays near perfectly but does not rip to Ogg near
perfectly?

-Jon
Ah, lamently, no. My gastronomic capacity knows no satiety.

<p><p>--- >8 ----
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