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Re: New Compression Technique: What to Do?

From "D. Stussy" <spam+newsgroups@bde-arc.ampr.org>
Newsgroups comp.compression
Subject Re: New Compression Technique: What to Do?
Date 2011-12-19 14:10 -0800
Message-ID <jcocnu$39u$1@snarked.org> (permalink)
References <48a9a490-2d47-4f43-adf1-e67cabb8251c@e2g2000vbb.googlegroups.com>

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"Harry Potter" <rose.joseph12@yahoo.com> wrote in message
news:48a9a490-2d47-4f43-adf1-e67cabb8251c@e2g2000vbb.googlegroups.com...
> I recently discovered a new compression technique.  On its own, it
> seems to be okay.  It can even provide a good compression ratio for
> files already compresed.  However, with LZW, I lose some
> compressibility, resulting in poor results.  My first goal with file
> compression is to create a *better* compression technique, and I still
> have ideas.  I know of Huffman codes and arithmetic coding and would
> like information on other techniques.  Any feedback would be
> appreciated.

LZW is hardly new.  Its original form was published in 1978.

The idea of compression is to identify repeating patterns and represent
them using fewer bits while non-repeating values get more bits.  When there
are more repeating patterns than not, the reduction in bits used overall
decreases, thus causing the benefit.  With small input, there's not enough
repeating data to make this economical, and often the compression
transformation may increase the size of the data.

There is one difference from the published algorith that may help:  The
algorithm specifies that it should reset its transformation codebook once
it fills.  That prematurely resets the stream.  Delaying a reset until the
codebook overflows (i.e. one entry more) is more useful, as existing
repeating patterns in the data at the point of fill can be absorbed into
the existing compression segment (where otherise, they would start a new
segment at the cost of lost efficiency).  This modification is what the
early 1990's DOS program "LHARC.EXE" did.

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Thread

New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-19 08:03 -0800
  Re: New Compression Technique: What to Do? "D. Stussy" <spam+newsgroups@bde-arc.ampr.org> - 2011-12-19 14:10 -0800
    Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-20 06:09 -0800
      Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2011-12-20 08:37 -0800
        Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-20 09:02 -0800
          Re: New Compression Technique: What to Do? Willem <willem@toad.stack.nl> - 2011-12-20 17:12 +0000
            Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-20 10:16 -0800
              Re: New Compression Technique: What to Do? Willem <willem@toad.stack.nl> - 2011-12-20 19:11 +0000
              Re: New Compression Technique: What to Do? Jim Leonard <mobygamer@gmail.com> - 2011-12-21 09:19 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-21 10:35 -0800
                Re: New Compression Technique: What to Do? Jim Leonard <mobygamer@gmail.com> - 2011-12-22 12:21 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2011-12-23 06:01 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2011-12-30 10:05 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2012-01-01 04:30 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-01-02 09:08 -0800
                Re: New Compression Technique: What to Do? Ernst <Ernst_Berg@sbcglobal.net> - 2012-01-24 08:18 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-01-24 12:56 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2012-02-02 10:50 -0800
                Re: New Compression Technique: What to Do? Thomas Richter <thor@math.tu-berlin.de> - 2012-02-03 09:07 +0100
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-02-04 20:33 -0800
                Re: New Compression Technique: What to Do? "George Johnson" <matrix29@charter.net> - 2012-02-07 07:48 -0500
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-02-07 09:47 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2012-02-08 06:25 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-02-08 06:55 -0800
                Re: New Compression Technique: What to Do? Harry Potter <rose.joseph12@yahoo.com> - 2012-02-08 07:11 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2012-02-08 08:21 -0800
                Re: New Compression Technique: What to Do? Earl_Colby_Pottinger <earlcolby.pottinger@sympatico.ca> - 2011-12-21 14:15 -0800
          Re: New Compression Technique: What to Do? pfraser <pete_fraser@comcast.net> - 2011-12-20 10:07 -0800
  Re: New Compression Technique: What to Do? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-12-20 20:19 +0000

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