Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??
The first char is emitted as simply that, an 8 bit value. Following that point all codes are emitted in longer than 8 bit form (starting with 9 bits until the table grows to have 512 values, then to 10 bits etc.).
A historical side-note: Years back I was doing some patent analysis, and read the Unisys LZW patent carefully several times.

Expanding the table to increasing the output byte width is Welch's improvement to the Lempel-Ziv compression algorithm, and this is what Unisys obtained a patent on. If you crippled your compression such that the table never grew past 256 values, you weren't infringing (in my "Not A Lawyer" opinion). Unisys allowed some FUD to surround this issue, not correcting the impression that it was GIF they held a patent on. Not so.


In reply to Re: LZW Demystified by dws
in thread LZW Demystified by demerphq

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others exploiting the Monastery: (6)
    As of 2015-07-03 06:36 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









      Results (48 votes), past polls