Re: estimate zlib compression ratio?


<tim.weiler@xxxxxxxxx> skrev i en meddelelse
news:1177427280.359990.242480@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Is there a fast way to estimate the zlib compression ratio for a file
(or any stream) without actually doing the compression?

For example, I need to send files over a socket, and some files are
jpegs, which don't compress that well, but other files are large text
documents with good compression ratios. I'd like to selectively
compress the files based on an estimated compression ratio.

A funny idea - you could compress a small part of the the file with QuickLZ
first (so fast that it has negligible CPU usage) and multiply that
compression ratio by some constant to estimate that of zlib.

Lasse Reinhold


.

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