Compressing GBs to MB-size RAR files?

[a745]

I need to back up this game I have (Tales of Destiny 2 for the PS2), and I've extracted its ISO (my brother kept on licking the CD... Is that bad?). Problem is, after doing that and putting the 3GB ISO in my Hard drive, it left me with only 10 GB available hard disk space (this PC's ancient, I know). And then I remembered this one time where my friend gave me a RAR file she downloaded which contained a 4GB ISO, and miraculously, that RAR file was only 49MB or something! I've tried using WinRAR and other compressors, but it still won't compress into something that small.

So, does anyone know of a way I can archive this ISO into a RAR file that's very small? It'd be fine by me if it could compress it to as big as a plain CD's capacity (700MB), that way, I can just burn it and keep it safe somewhere...

Thanks in advance ^_^. I hope someone can help T_T.

[foxyshadis]

What you're asking for makes no more sense than asking how to zip a zip file to 1/6 of its size; both are already heavily compressed. That trick only works with log files and other very-compressible files. Your options are to spend a few days re-encoding everything to a much lower bitrate, keep just your favorites, burn them to a DVD, or pry a crowbar in your wallet and buy an external hard drive.

[a745]

What you're asking for makes no more sense than asking how to zip a zip file to 1/6 of its size; both are already heavily compressed. That trick only works with log files and other very-compressible files. Your options are to spend a few days re-encoding everything to a much lower bitrate, keep just your favorites, burn them to a DVD, or pry a crowbar in your wallet and buy an external hard drive.

Oh sorry, wrong info. I was talking about a game ISO.

And I HAVE seen files like that.

[Guest]

If you've tried compressing it without success, then it is not compressible.

[foxyshadis]

Heh, the original Tales of Destiny is an example where you could do that, it compresses to less than 30%. All games have different levels of compressibility though, whatever 7z and rar give you is the best you can get, or about 1-2% more for compressors that takes hundreds of times as long.

There are ways that you can edit the contents, removing high-res textures and speech, but you have to be very experienced at disassembly and reassembly. I don't know much about it, and this isn't really the forum where experts would gather.

[Dark Shikari]

Most games these days are 98% media... either already-compressed textures or video/sound that's already compressed.

Maybe old games were compressible, but today everything comes pre-compressed in most cases.

Even if its not compressed, textures rarely compress beyond 3-5x.

Of course, you can try a more efficient compressor, like PAQ8O, which blows the socks off RAR by a huge margin.*

*Compression program may require a few weeks to compress and decompress a multi-gigabyte file.

[Shinigami-Sama]

I remember hearing ACE was good for ISOs, I've seen 400-600meg ACEs become 1-2gig ISOs
was slow as hell though

[Dark Shikari]

I remember hearing ACE was good for ISOs, I've seen 400-600meg ACEs become 1-2gig ISOs
was slow as hell though
ACE is a pretty crappy compression algorithm; mildly better than ZIP but not even close to RAR, which in turn pales in comparison to the completely free and open-source 7zip.

The best practical compression algorithm is without a doubt 7zip's LZMA, which let me fit a stripped-down version of Supreme Commander (2.4GB) into under 700MB to distribute for playing at LAN parties.

The best ever compression algorithm is whatever the latest version of PAQ8 is.

[burfadel]

If you have a DVD burner you could burn the image file on to it (as an image file, not a copy of the disk)...

Alternatively, you can use 7zip/RAR and use the span option (CD size) and burn it over several CD's. You can then hide them somewhere where your brother doesn't lick them :D

[CWR03]

You could always put some of that stuff on the disk that people use to stop their nail-biting habits. I read a positive feedback on eBay from someone who'd bought it that read "Tastes like crap - thanks!"

[insomniak1981]

For compressing .iso's try poweriso to compress to .daa. It won't give the results you want, but it will give much better compression than .rar and in good time.

[St Devious]

Dude there's no way u can compress any game that much .

And the 49 MB rar file u were talking about was only one of the no. of rar files which contained total ISO file. The 4 GB ISO was split to 49 MB parts using Winrar . So u cant extract 4 GB out of one part . u need all the parts to get back the 4 GB ISO file . And maybe she doesn't know too much about winrar splitiing thought whole ISO was in one part .

[Dark Shikari]

For compressing .iso's try poweriso to compress to .daa. It won't give the results you want, but it will give much better compression than .rar and in good time.DAA is definitely not better than RAR; the reason it is used is because the DAA can be accessed on the fly, the RAR has to be extracted.

The main problem is that DAA is a completely proprietary format, and so nobody uses it.

[point_vector]

Hey, All these people are calling you crazy for seeing a file that small. I saw one just the other day that was a GAME. It is a .rar file. If you extract that, it is usually an .ace file broken up into something like 30 little cr1 -cr30 or something like that. If you extract the .ace file, you get either an .iso, or a .cue and a .bin, or a .mdf and a .mds file; depending on the copy protection of the game. ANYWAY, that is a lot of compression, but it can be done. The game I saw, by the way, if you analyze it with winrar, was compressed at 78%. It was almost a 5 gig game that was compressed down to the size of a cd. I'm sorry this isn't going to help you in your quest to do it yourself, but I wanted you to know that your not crazy. And don't worry, I rarely get help from these forums. When I write, I just see the same things posted here, all telling me the same things I've already tried or someone posting just to get their post numbers up. I am trying to find something myself and if I do I will contact you right away.
Laters

EDIT


You could compress it as much as you could, then use winrar to break it up into multiple smaller files that you could burn onto a couple of cd's

[Maccara]

Are you sure the small .rar file you saw was not a kind of maxi-image, which is used just to be able to play the game without needing the original dvd in the drive?

Those compress well, as they're mostly 0's.

[systemloc]

Ahhh, I remember what this guy is talking about. I saw quite a few releases of games that were compressed down to mere fractions of the originals. The Rainbow Six series was popular for this, but I'm sure there were others.

The trick was that whoever had released it had cracked the texture file format for the game, extracted the raw media, and used a lossy compression scheme to radically reduce the size. When you installed it using their installer, it would re-inflate the media for the game to use, but of course, the quality suffered pretty heavily, as the lossy compression lost so much of the detail.

This technique hasn't been done in a long time to my knowledge. It's purpose was to overcome dial-up connect speeds and small hard drives, neither of which are a problem any more. It was also labor intensive, as you had to hack the media storage mechanism of each individual game (or series).

a745: Couldn't you just burn the ISO and delete it off your hdd? Make 2-3 copies and keep the extras stored safely and don't use them. :)

[Guest]

The trick was that whoever had released it had cracked the texture file format for the game

I'm closing this thread as it is now in rule 6 territory.

systemloc, don't ever discuss cracks again on this board.