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warkbt
31st March 2009, 02:13 PM
Hi, I am trying to compress some .bin that are part of disk images. They are nearly 750mb. However no matter the compression tool I use I can only reduce it 5mb. For example:



$ lrzip cd1.bin
Output filename is: cd1.bin.lrz
53%
99%
The cd1.bin - compression ratio 1.002
Total time: 0h 25m 2.769s

Crap, 25 minutes wasted. I have already test it with lrzip, tar via bzip2, p7zip and no one work as I want. Is there a tip to get a better compression ration like put all the .bin together or extracting the files?:confused:

Any help would be appreciated:)

sideways
31st March 2009, 03:34 PM
Not really, the bin is probably already compressed by a packer utility (like upx)

Some files can't be compressed much further, in fact, theoretically, for any given compression algorithm there exists an infinite number of files which can not be compressed at all, and in some cases the compressor will actually expand the size of the file!

JohnVV
31st March 2009, 06:22 PM
and in some cases the compressor will actually expand the size of the file!
just try and zip,bz2,... a photo.png file the archive WILL be bigger that the photo

warkbt
31st March 2009, 06:33 PM
Well thanks for answering, but it doesn't help me too much...

JohnVV
31st March 2009, 06:35 PM
for a bunch of files there is sometimes no way to compress them farther . That is Life , live with it .