Forum: UltraISO
Topic: Compression ISZ
started by: MrChris

Posted by MrChris on Jul. 01 2006,02:19
If I have a full 700MB Compressed ISZ file and I burn it to a CD then what happens to the compressed data after it is put on the media? Is it uncompressed? If so how does it still fit on the CD if it was 700MB Compressed?

Thanks,

MrChris



Posted by MrChris on Jul. 01 2006,02:45
And does it matter if the data is "Optimized" like when using/creating a All-In-One Windows'XP CD/DVD/ISZ/ISO?
Posted by xoben on Jul. 01 2006,05:46
QUOTE
And does it matter if the data is "Optimized" like when using/creating a All-In-One Windows'XP CD/DVD/ISZ/ISO?

'Optimize' works with ISZ format properly.

QUOTE
If I have a full 700MB Compressed ISZ file and I burn it to a CD then what happens to the compressed data after it is put on the media? Is it uncompressed? If so how does it still fit on the CD if it was 700MB Compressed?

An ISZ file is data file simillar to RAR and ZIP. If you put it on a CD, Windows see it as a plain file.

Posted by MrChris on Jul. 01 2006,13:19
I am referring to burning the ISZ image file to the CD so that all the content inside the ISZ file is visible on the CD after its burned. What happened then?

Im not referring to simply copying the ISZ FILE to the CD.

MrChris

Posted by xoben on Jul. 01 2006,21:14
QUOTE
I am referring to burning the ISZ image file to the CD so that all the content inside the ISZ file is visible on the CD after its burned. What happened then?

At present, you can use UltraISO to burn an ISZ file, the final CD will be the same as burning from a standard ISO.

Posted by MrChris on Jul. 02 2006,03:58
OK I did some testing. And what I was after/thinking does not seem to work, as I didn't think it would. Without having some type of new/special CDFS.

I have a single 713MB Bootable 9in1 XP ISO that fits on a single CD just fine. I took that and added about 75MB of more data and saved it as a ISZ file and after it was compressed my ISZ file was then 705MB which is smaller than that of the uncompressed ISO.

I tried to then burn the ISZ file to a CDRW and UltraISO said there was not enough blocks on the media.

So my guess is that based on what "xoben" said and I have found is that UltraISO must decompress the ISZ file when burning it to the CD/Media.

So then the ISZ file is really no more than just another type of ZIP or RAR file for example. The only difference is that you can Mount an ISZ file as a drive letter, maybe.

What other benefits are there to having your data inside a compressed ISZ over a ISO file?

Regards,

MrChris

Posted by xoben on Jul. 02 2006,05:00
Thank you MrChris for your detailed information.

QUOTE
What other benefits are there to having your data inside a compressed ISZ over a ISO file?

1) Password protection - you can protect your ISOs with AES256 encryption under shared environment, for example, transfer private ISO via internet
2) Spanned CDs&DVDs - you can split large ISOs to several small volumes, for example, spilt a DVD ISO to several CD-R size files, so you can burn them to CDs. Backup whole disk or a very large files is also benifited from this format.
3) Compression - in fact, you can backup your 703M ISZ as a single file to your CD-RW device and use it later.