batch convert mp3 to ogg

[James Wilkinson]

Robin Laing wrote:
> There is an interesting comment about oggenc will only work with wav files.
> 
> From the man page.
> "oggenc reads audio data in either raw, WAV, or AIFF format and  encodes 
> it  into  an  Ogg  Vorbis stream."
> 
> This would imply that to go from mp3 to ogg, you will have to convert 
> the file to a wav, raw or AIFF.  Then create the ogg file.  Again, each 
> process has the risk of creating more distortion.

Er: no.

Both FLAC and wav [1] are lossless compression formats. You can go from
one to the other to the raw data all day without losing anything[2] or
creating any distortion[3]. That's the point of FLAC: it stores
*everything* in a relatively small amount of disk-space.

You can also go from MP3 or ogg to wav without losing any more data.
(You lost some when you created the MP3 or ogg in the first place:
that's still gone, of course).

So (if you're using a fixed-width font...):
FLAC ------------> wav -----------> ogg
     no data loss       data loss

MP3 (some data   -----------------> wav ---------------> ogg
already lost)    no data loss here       more data loss

The data loss involved with going to ogg (or MP3) has to do with the
output format, not the input. 

James.

[1] Well, I seem to remember coming across some MP3s stored in a WAV
format. Apart from them...

[2] Apart from (possibly) some metadata like the name of the artists...

[3] Assuming that your computer's reliable...

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E-mail address: james | "I never really understood how there could be things
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