On Mon, Aug 02, 2004 at 05:13:07PM -0500, Joe Wreschnig wrote:
> This is why I drew a distinction between "creation" and "modification"
> before; the "created" form (huge uncompressed wavs) don't give you much,
> if any, more "editability" than Vorbis, in the sense that you can apply
> filters, cut, etc, Vorbis files just as well as wavs.
No you can't. Consider that many filters will change which part of the
audio are perceivable. Vorbis (attempts, at least) to not store the
non-perceivable data; so now you can no longer do that. Or, rather you
can try, but it'll sound horrible.
Even a few decode/encode cycle loses quality. As a quick test, I took a
copy of Brahm's German Requiem's "Denn Alles Fleisch" that I have in Ogg
Vorbis format, decoded it, and re-encoded it. Here are the file sizes,
in kilobytes:
150460 decoded (wav)
15648 original (ogg)
14424 re-encode (ogg)
Both ogg files were produced with the same encoder (oggenc). Same
version of that encoder (20020717). Same quality (-q5). Yet, the
re-encode is nearly 8% smaller.
I imagine another pass will lose another 8%. That's not useful source.
