Curious about this compression method...

[gildedlink]

How is this compression done for knoppix? Are there special programs (preferably in windows) that can run this type of compression easily? I have an iso file that's larger than 700 mb and I have to fit it on a 700 mb cd-r (I tried burning it to DVD but Nero didn't allow me), would there be any easy way to try to compress that iso file using this technology?

[Harry Kuhman]

Compressing an iso file before burning it is pointless (unless you are just trying to keep a copy of an oversized iso). You can not make and iso, compress it, and expect to burn it as an iso image.

This would be like trying to fit lots more than 80 minutes of audio on an audio CD and trying to play it in a standard audio cd player by compressing the files before you did so (not talking about mp3 files here, just typical audio).

[gildedlink]

Well my general goal is simply to make the iso file fit on the disc overall, so that is done as the disc is being burned? I figured something was done to compress the disk image from 2GB worth of software in knoppix to an iso file of close to 700mb, but I wasn't quite clear on the details of it in the first place.

[Harry Kuhman]

Well my general goal is simply to make the iso file fit on the disc overall, so that is done as the disc is being burned? ......

No, an ISO that is too large cannot be made to fit on a CD "while burning" (not counting "overburning", which doesn't seem to be the issue here).

What is this ISO that you speak of? If you have remaster and created an ISO with more stuff on it, then it is likely that the ISO is too large and something will have to be removed to make the ISO smaller. This has been happening to Knoppix since I first saw it, every time something has been added to Knoppix, other things have had to be removed to make space for them. There were a lot more games on 3.1 than on the current Knoppix CD's. Some other things have been removed too.

On the other hand, at least one person has posted insisting that the Knoppix ISO he downloaded is too large, but he also insisted that the md5 checksum matched the published md5 sum. If the md5 file matched, then his ISO was certainly not too large and not as large as he was insisting it was. He never did post about the final resolution of the problem or what the confusion was though, as far as I know.

Compression is used to make one of the files in the iso. This results in a file on the CD that is less than 700 megs in size but holds about 1.8 gig of applications (based on their size before the compression). But the ISO (an image of all the files as they will be written to the CD) cannot be further compressed. Maybe someday someone will apply a differnt compression approach to the file that contains all of the applications and in doing so gain a little more space, but the current approach is pretty efficent and hard to improve upon.

[sunburnt]

I think gildedlink is talking about the fact that Knoppix advertizes that
up to 2 GB of stuff is put on the CD, and he wants to know how to do it.

The bulk of the stuff on the CD is compressed into a file called "Knoppix",
if you look on the CD you'll find it, and it's a little less than 700MB.

The compression format is called "cloop", it's part of the Debian packages.
Debian and Linux has tools for it of course... Win. I doubt it, maybe never.

Don't know much more, see my post: "how Knoppix works? ... boot & cloop".

[eadz]

I think you're looking for a program like WinZip ( or check out 7-Zip - free alternative ).
Zip up your files, then burn them onto a CD.

Knoppix's 2GB compressed to 700Meg is just that.. a compressed file. The ISO itself is not compressed.

[garyng]

There must be some Window apps that can do the same but I believe it needs $$$.

Under linux, just use squashfs or cloop. I believe squashfs is the way to go as it seems to be the next candidate to be in vanilla linux kernel.