[vorbis-dev] Re-encoding digital broadcast to Ogg?

[Daniel B. Miller]

...
> As the world progresses into digital broadcast, does this mean that we'll
> be lumbered with whatever the original compression method is?
>
most likely, yes.  However, note that _most_ digital transmission
standards (at least for audio) are higher datarate than Vorbis, and
presumably have near lossless quality.  I don't think re-encoding AC3 at
say 384 kbits/stereo, encoded professionally from a digital source, should
be as bad as say starting with a 128-kbit MP3 encoding done off the analog
output of someone's discman to their soundblaster.

In the worst case, I would think upping the datarate considerably would
resolve most problems.  If you're recording for your own use, local
storage allocated to audio is probably not your biggest budget item.

> Does this mean that some form of rudimentary copy protection can be implemented
> by encoding in a peculiar way so that if the audio is re-encoded it will
> result in a bad quality recording?

Studios & various tech. companies are working on this.  see for instance:

http://www.newsfactor.com/perl/story/12166.html

Recently I saw an example of a similar technology built into a set-top
box.  Unfortunately, the artifact was already clearly visible on a
television monitor.  I assume the intent was for an artifact to appear on
copies only.

 >
> Simon Wood
>
 ___  Dan Miller
(++,) CTO and founder, On2 Technologies

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