Getting good compression in WinRAR (or anything else)...

Richdog · 27 Jun 2009 at 10:02

I'm a bit confused... i'm trying to RAR a set of game files but the best compression I can seem to get using "Best" is 98%-99%... making it almost pointless. I get the same issue with other files too using WinRAR, I'm not too knowledgeable in this area but I thought compression was supposed to be able to almost half things in most cases, and that WinRAR was among the bes. Any tips guys? :confused:

smogsy · 27 Jun 2009 at 10:21

i have found streams/code files they don;t drop the size at all tbh they only seem to reduce size of pictures or media/documents

you could try 7zip it supposedly very very gd

flip · 27 Jun 2009 at 10:29

Some files are already compressed, so you cannot compress them again

Try compressing a large txt file, and you will get a huge compression ratio. but things like mp3 and jpg are already compressed files so cannot be compressed any further

fliP.

Richdog · 27 Jun 2009 at 10:35

AHhhh I see, that explains it I guess. Thanks guys.

bledd · 27 Jun 2009 at 11:36

many files have optimised filesizes, such as mp3, divx and in this case, your game files

zzzJonny · 27 Jun 2009 at 12:59

Yep, they've likely already pushed down the filesizes already, so you can't get much lower by compressing.

HangTime · 27 Jun 2009 at 19:30

OK first up WinRAR isn't really among the best if you are concerned about compression ratio. It is however very widely supported and has an excellent GUI interface coupled with decent speed.

Best "balanced" tool (i.e. user friendly, gui, freeware, compression/speed ratio, widespread usage) to use is 7zip Ultra LZMA with a large dictionary size. That will beat RAR comfortably.

NanoZip looks like a very promising up-and-coming archiver and could arguably become the 'new 7zip' if pushed hard enough. Only in alpha stage at the moment but already has a (basic) gui and beats 7z compression. I'll certainly be keeping an eye on this one.

If you want some really hardcore compression I haven't found anything better than PAQ8. I did some tests at work and it absolutely wipes the floor with mainstream formats like .rar and .7z in terms of file size. HOWEVER, as I mentioned it is a hardcore tool which has no GUI and is very much focussed on compression ratio over speed. We're talking hours and probably days to compress a DVD game here.

In terms of realworld practical use PAQ8 will never win many friends due to the above, however the geek in me just likes the fact that it creates the smallest archives