On 7/6/2010 12:14 AM, Paul Gilmartin wrote:
And that doesn't help.
Yes, it does. There will still be cases where any compression produces larger output, but it is more likely that when one method fails, another will show improvement.
Just consider PKZIP in its entierty as a complex compression algorithm with several subroutines. The formal proof applies to PKZIP regardless of its internal complexity.
While your statement sounds plausible, it's not compelling. Neglecting special and degenerate cases, a compression method will shorten 50% of the input, and lengthen the rest. Taking a different compression method, it also will compress 50% if the cases, but not the same 50% (by my definition of "different"). While there will be overlap, the total number of compressible data have now increased to more than 50%.
Gerhard Postpischil Bradford, VT ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
