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Topic: information theory?
Replies: 83   Last Post: Dec 22, 2011 5:14 AM

 Messages: [ Previous | Next ]
 Rich Delaney Posts: 392 Registered: 12/13/04
Re: information theory?
Posted: Dec 21, 2011 8:49 PM

On Nov 4, Martin Brown <|||newspam...@nezumi.demon.co.uk> wrote:
> > He estimated music contains 40 bits/second entropy.
> > How close is MP3 to that?

>
> >___________________________________
> >I doubt surprised Shannon said that, and if he did its
> >somewhere between meaningless and wrong.

>
> >CD quality mp3s are roughly equivalent to 178 kbps,
> >over 4,000 times his estimate. But then you can
> >encode a lot of sounds that most people would not
> >consider music. And it stereo, so you can halve it
> > if Shannon was talking about mono.

>
> Have you never seen sheet music? That is what
> Shannon was estimating - the bitrate for describing
> music in the abstract.
> There are a finite number of notes, durations and
> amplitudes in a classical composition.

I suspect that's the case.

> I suspect 40 bits/sec is still far too tight,
> but a midi stream using a high end reconstruction
> codec represents a pretty good
> example of what is possible by way of compression
> for *music* as opposed to voice or a random noise
> stream.
>

> > To get a smaller figure for music, you have to
> > define what subsets of sounds are music. Lots of luck.

Not so hard, if you analyze samples of what we label 'music'.

> I think that may have been his intention although
> I don't recall seeing the 40 bit/s number
> As I said if he did anything I think he was estimating
> the information content of music in the already
> concise form of an orchestral score.

That appears to be the case.

> I reckon at a bare minimum about 7 to the note, 8 to
> amplitude, 6 duration, 5 to the instrument - and it
> is already obvious that you cannot encode more than a
> single note per second at this bitrate.

You fail to account for the essential concept
of correlation.

> Can anyone provide a citation to this alleged paper
> on music bitrate?

I found the reference in John Pierce's book.
It's not attributed to Shannon. My boner.
He claims a humans can absorb information,
e.g. reading or music, at 40 bits/second.
He also cites a paper where it's claimed that
sheet music contains 2.5 bits entropy per note.
This supports the MIDI model, as opposed to
digitization of a recording. In that case,
what is the bit rate? Though the question of
chords arises, with much redundancy there.

It also raises the possibility that recorded
music might be adequately represented by a
MIDI stream.

--
Rich

--
Rich

Date Subject Author
10/31/11 Rich Delaney
11/1/11 Eric Jacobsen
11/1/11 Chris
11/1/11 Rich Delaney
11/1/11 jim
11/1/11 jim
11/1/11 Cindy
11/1/11 BJACOBY@teranews.com
11/2/11 jim
11/2/11 BJACOBY@teranews.com
11/2/11 jim
11/2/11 Cindy
11/2/11 jim
11/3/11 Cindy
11/1/11 BJACOBY@teranews.com
11/2/11 Les Cargill
11/3/11 Andrew Haley
11/3/11 gdewilde@gmail.com
11/2/11 Martin Brown
11/2/11 JohnF
11/2/11 Martin Brown
11/2/11 Martin Brown
11/2/11 Bernd Jendrissek
11/2/11 David Eather
11/2/11 Bill Unruh
11/24/11 J. Clarke
11/24/11 Martin Brown
11/25/11 Richard Outerbridge
11/25/11 Les Cargill
11/2/11 Rich Delaney
11/3/11 Martin Brown
11/2/11 Chris
11/2/11 robert bristow-johnson
11/2/11 Rich Delaney
11/2/11 VWWall
11/2/11 Richard Outerbridge
11/4/11 Frederick Williams
11/4/11 krw@att.bizzzzzzzzzzzz
11/4/11 jim
11/4/11 Jerry Avins
11/4/11 Greg Rose
11/5/11 Frederick Williams
11/5/11 Mike Terry
11/5/11 MrTallyman
11/5/11 R Kym Horsell
11/5/11 MrTallyman
11/5/11 unruh
11/5/11 krw@att.bizzzzzzzzzzzz
11/7/11 JW
11/7/11 krw@att.bizzzzzzzzzzzz
11/7/11 MrTallyman
11/7/11 krw@att.bizzzzzzzzzzzz
11/4/11 FigureItOut
11/6/11 jim
11/4/11 Rich Delaney
11/4/11 BJACOBY@teranews.com
11/4/11 Peter Webb
11/4/11 robertwessel2@yahoo.com
11/4/11 R Kym Horsell
11/4/11 Peter Webb
11/4/11 VWWall
11/4/11 jim
11/4/11 jim
11/4/11 Androcles
11/4/11 Martin Brown
11/4/11 Peter Webb
11/4/11 BJACOBY@teranews.com
11/4/11 Jerry Avins
12/21/11 Rich Delaney
12/21/11 Les Cargill
12/22/11 Richard Outerbridge
12/22/11 Martin Brown
12/22/11 Peter Webb
11/4/11 Androcles
11/4/11 Casper H.S. Dik
11/4/11 Bill Unruh
11/6/11 jim
11/7/11 jim
11/7/11 jim
11/8/11 jim
11/8/11 Michael A. Terrell
11/3/11 BJACOBY@teranews.com
11/3/11 Chris
11/3/11 Chris