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Re: Using various kinds of frequencies

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Mok-Kong Shen <mok-kong.shen@t-online.de> wrote:

(snip)
>>> If one in the space of, say, 8 bits, optimally allocate a part to the
>>> most freqeunt words, a part to the most frequent digraphs and finally
>>> a part to the single characters, couldn't that eventually be better
>>> than a common Huffman coding based on frequencies of single characters
>>> alone? If that has already be tried out, could someone give reference
>>> informations? Thanks.

(snip)
> I mean the following: An 8-bit byte has a coding space of 256. One could
> allocate a part of it to code some high frequency words, another part
> to code some high frequency digraphs and the rest to code the
> alphabetical characters. I assume also that these frequencies are
> known (averages of natural language texts). I like to know whether
> that would result in some compression that is not too bad as compared
> to, say, Huffman applied to single characters as usual.

If you only know byte (character) frequencies, but not digraph
or higher, then single character Huffman is the best you can do.

If you know more, then you can use that information.

You could just Huffman code byte pairs, which would automatically
code digraphs (some directly, some as the first or last character
of another pair), and code single characters about as well as
single character Huffman.

-- glen

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Thread

Using various kinds of frequencies Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-09-22 11:17 +0200
  Re: Using various kinds of frequencies Thomas Richter <thor@math.tu-berlin.de> - 2012-09-24 11:01 +0200
    Re: Using various kinds of frequencies Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-09-24 23:13 +0200
      Re: Using various kinds of frequencies Willem <willem@turtle.stack.nl> - 2012-09-24 21:25 +0000
      Re: Using various kinds of frequencies glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-09-24 22:20 +0000
      Re: Using various kinds of frequencies "George Johnson" <matrix29@charter.net> - 2012-09-24 20:57 -0400
      Re: Using various kinds of frequencies Thomas Richter <thor@math.tu-berlin.de> - 2012-09-25 10:50 +0200

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