"ogg theora" is a "free" format, created in response to mp3, to be a
lossy format which isn't weighed down by patents, royalties and legal
issues.. which is why the hardcore open source advocates like to push
it.. and why it's so disappointing that so few devices and software
support it -- they don't have to pay royalties to use it, and the
libraries and code are all there for free. Ogg is just the container
format, but the compression engine (codec) used within it can vary.
Theora ("Ogg Theora") is the lossy mp3-like one, and FLAC ("Ogg FLAC")
is for audio with lossless compression.
So apart from the usual ogg audio codec (theora) there's also FLAC
which is a losslessly compressed format (usually does about 2:1
compression with zero loss of quality), so you can upload squeakily
perfect audio to Wikipedia too, if you can work out how to encapsulate
FLAC files within an OGG container.
The open source audio editor "Audacity" _does_ support import and
export to ogg (theora) natively, and is quite usable without a
computer science degree. Rather than choosing a bit rate for ogg,
you're just given a "quality" slider that goes from 0 to 10 when you
hit the options button during save (Ogg Theora seems to generally use
VBR). Audacity is available for Windows, OS X and Linux (all for free).
And it just exported a 96 kHz file to ogg and kept it 96k for me. I
recommend the latest beta version, which has an improved noise
reduction filter and better support for ogg out of the box. It exports
FLAC too, but I don't think it puts it into an OGG container (e.g. the
file extension is FLAC, not OGG like it should be. hmm.)
http://audacity.sourceforge.net/
The command line "OggEnc" gives you more control over min and max bir
rate, and plenty of useless options, and lets you set metadata when
you're encoding (artist, album, etc)
Also check out the vorbis web site. The "Windows" and "MAC OSX"
buttons give links to encoders as well as players.
http://www.vorbis.com/
Peter Halasz.
--- In "Bruce Wilson"
<> wrote:
>
> Forgot to add, max frequency is 48kHz, so if you want to make an ogg
file of
> your his-res recording, you can't with this app. Bit depth, is, of
course,
> limited to the quality of your lossy conversion, no more that 8-10, I
> believe.
>
> Bruce Wilson KF7K
> http://science.uvsc.edu/wilson
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