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NewsArchive
10-05-2012, 01:13 AM
As a general rule of thumb, what is the compression factor with this
function? I know it is a ballpark factor but need a starting point.

Thanks


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Darrel (Dee) Witham
Professional Data Services, Inc

NewsArchive
10-05-2012, 01:13 AM
> As a general rule of thumb, what is the compression factor with this
> function? I know it is a ballpark factor but need a starting point.

You can't "calculate" the compression ratio (aka compression power). The
actual ratio depends on the type of the data being compressed. Files with a
repetitive data structure (i.e. images with large white areas) result in
smaller archive files than those of a more random nature.

It is possible to see compression ratios as high as 99.99%, yet it is also
possible to get very little or no compression at all. This depends on the
type of data being compressed. When compressing text files, e.g. Word
documents, ASCII text files, Excel or emails, the compression ratio will be
very high. When compressing binary files or files already compressed (.MP3,
..RAR, .7Z, .ZIP, .JPG), the compression ratio will be lower.

--
Friedrich Linder
Lindersoft
www.lindersoft.com
+1.954.252.3910

Helping You Build Better Installations
SetupBuilder "point. click. ship"
Official Comodo Code Signing and SSL Certificate Partner

NewsArchive
10-05-2012, 01:15 AM
Encrypted files don't compress much either.

e.g., compare a compressed TPS with a compressed encrypted identical
TPS.

>When compressing binary files or files already compressed (.MP3,
>..RAR, .7Z, .ZIP, .JPG), the compression ratio will be lower.

Jeff Slarve
www.jssoftware.com
www.twitter.com/jslarve
I'll search help files & Google for you.

NewsArchive
10-05-2012, 01:15 AM
> Encrypted files don't compress much either.
>
> e.g., compare a compressed TPS with a compressed encrypted identical
> TPS.

Yes, that is correct!!

Friedrich

NewsArchive
10-05-2012, 01:16 AM
In my experience, the compression ballpark figure is somewhere between
1% and 99% compression <g>. But it does always seem smaller.

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Russ Eggen
RADFusion International, LLC

NewsArchive
10-05-2012, 01:17 AM
Russ - thanks<VBG>

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Darrel (Dee) Witham
Professional Data Services, Inc