[vorbis-dev] ogg pic format (again).. here's why

Marshall Eubanks tme at 21rst-century.com
Fri Jan 26 21:09:50 PST 2001

Hello Tarkinauts;

Does anyone know how much a 3 or 4 D LOSSLESS compression could be
pushed ?
I have a feeling with video you could do a LOT better than Huffman encoding.

I remember that with Voyager, first pixel of each row was sent 16 bit (I
think), and then
each subsequent pixel was sent as a delta (from the previous pixel),
then runs were encoded, then
everything was formated  in blocks with error correction, 
with an average bit/pixel of like 3 or 4 or so, even over
landscapes (this was adopted originally as, for a pictures of moon
against black space,
long runs of black background could be in very few bits). (I may not
remember the steps in the
right order; it's been a long time.)

This is a 1-D lossless compression, with no fourier transforms or
wavelengths involved. 
I suspect that a factor of 10 would be easy,
and a factor of 100 possible, with lossless compression, if you went all

This, of course, would have some real attractions.... 

                                   Marshall Eubanks

   Multicast Technologies, Inc.
   10301 Democracy Lane, Suite 201
   Fairfax, Virginia 22030
   Phone : 703-293-9624          Fax     : 703-293-9609     
   e-mail : tme at on-the-i.com     http://www.on-the-i.com

Olaf van der Spek wrote:
> ----- Original Message -----
> From: <rillian at telus.net>
> To: "Gerry" <gerry at c64.org>
> Cc: <vorbis-dev at xiph.org>
> Sent: Friday, January 26, 2001 11:13 PM
> Subject: Re: [vorbis-dev] ogg pic format (again).. here's why
> > > The ogg video-format [...]needs a way to compress its
> > > frames. Are you going to use MNG for that ? :) ..
> >
> > No. The advantage of MNG is that it offers lossless compression if you
> want
> > it. Tarkin will be a (very) lossy encoder specifically for video; the
> design
> > requirements there are quite different and are best implemented as a
> separate
> > format.
> >
> > MNG can be used as a high quality "source" format for video such as one
> needs
> > for editing and effects work. Tarkin would be the final output format for
> electronic
> > distribution.
> >
> > It was also my proposal that we use MNG for overlays on top of tarkin
> video,
> > a la DVD subtitles. With text and other annotations the lossless nature
> and
> > support of limited color palettes is a real win. And because of jng,
> there's
> > support for lossy continuous-tone images as well. (think "pop-up-video")
> AFAIK MNG doesn't support paletized images.

--- >8 ----
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