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Recursive Acronym
Advanced Member
Joined: 11 Dec 2006
Posts: 499
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 Posted: 28 Mar 2007 09:24:59 pm Post subject: |
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I was wondering how exactly data compression worked. I would like to make or use an existing data compression/decompression algorithm to be run on the Z80. I saw an algorithm for "Ion Compress" on WikiTI, but it says that it is untested.
Last edited by Guest on 30 Mar 2007 03:36:17 pm; edited 1 time in total |
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WikiGuru
ADOS (Attention deficit... Oh! Shiny!)
Elite
Joined: 15 Sep 2005
Posts: 923
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| Posted: 29 Mar 2007 04:03:11 pm Post subject: |
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| I'm not sure exactly how data compression exactly works, but I think there's an example in Sigma's learn asm in 28 days. |
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Liazon
title goes here
Bandwidth Hog
Joined: 01 Nov 2005
Posts: 2007
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| Posted: 29 Mar 2007 06:18:48 pm Post subject: |
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You could always try writing your own RLE Compression routine.
And iirc, in Day 9 of ASMin28, Sigma is just pointing out that if your max value for a piece of data is less than a byte, than you might as well use only the number of bits you need and squash another piece of data that's less than a byte next to it so you save some bits per data structure, which eventually add up to many bytes. |
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Recursive Acronym
Advanced Member
Joined: 11 Dec 2006
Posts: 499
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| Posted: 30 Mar 2007 06:57:01 am Post subject: |
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| I wanted to know how to compress 7-bit ASCII text, so I was thinking about representing each letter as well as 5 common characters with 5 bits, then using the only remaining combination combined with 7 more bits to represent the rest of the character set. RLE also looks possible, but not too promising. What do you think? |
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sgm
Calc Guru
Joined: 04 Sep 2003
Posts: 1265
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| Posted: 30 Mar 2007 04:39:20 pm Post subject: |
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| There are already Pucrunch and Apack compression/decompression methods (c/o Dwedit) you can use that are very effective at compressing text. |
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