Because people often refer to cd based images as "iso" - probably because .iso was the first format that showd up.
packISO is just a set of tools designed to give better compression but still creating the same archive on any platform/pc.
You could do those steps manually, but packISO just creates the batch files for you and executes them. 
ECM only works for CD images (not DVD), and only for .bin/cdi/mds with a sector size of 2352 compared to .iso with 2048 sector size. (ISO file format does not store EDC and ECC data).
ECM checks this EDC and ECC data and removes it when it matches the calculation of that sector. (It is a bit more advanced, though)
For Wii DVD images you do not need that. You would just scrub the image with WiiScrubber (with creating a diff file) and then use 7zip 4.57 with the standard options to compress the image.
Well, so far what packiso did was just this:
use ECM on the first track, then just call 7za on the file: "7za a [...]"
If everyone uses the same 7zip version, it should be the same file for everyone.
The normal add operation uses a dictionary of d=16MB, means it needs 11.5*d+3.5 MB of memory to compress the file. Using ultra compression uses a larger dictionary, but this means, more memory for compression is needed. Computers with less than 1.5GB RAM won't be able to use ultra compression at all. (It might be possible on computers with 1GB, but this means that no other tasks must be running, that you have around 700MB free)
If everyone uses the same 7zip version, it should be the same file for everyone.
Actually No, it will not create same Archive on different PCs, if you look into your Packiso folder, there will be a file called RMDtrach.exe (or somewhat similar name), that exe it what make it possible to get same images on different PC.
now for wii, search this forum for packps2 and use that to compress DVD base image, it will create same archives on different PCs, just a note, packps2 has been only tested for PS2 images, so thou it should work ok for wii also, making a backup is highly recommended.
Sotho Tal Ker wrote:If everyone uses the same 7zip version, it should be the same file for everyone.
Actually No, it will not create same Archive on different PCs, if you look into your Packiso folder, there will be a file called RMDtrach.exe (or somewhat similar name), that exe it what make it possible to get same images on different PC.
Well, yes, i forgot rmdtrash. What is does is zeroing the created/modified/accessed times.
Still 7za will create exactly the same files on different machines with exactly (Which means file times are identical, too) the same source files.
6 2008-09-24 05:46:42 (edited by BadSector 2008-09-24 05:48:00)
BadSector wrote:Sotho Tal Ker wrote:If everyone uses the same 7zip version, it should be the same file for everyone.
Actually No, it will not create same Archive on different PCs, if you look into your Packiso folder, there will be a file called RMDtrach.exe (or somewhat similar name), that exe it what make it possible to get same images on different PC.
Well, yes, i forgot rmdtrash. What is does is zeroing the created/modified/accessed times.
Still 7za will create exactly the same files on different machines with exactly (Which means file times are identical, too) the same source files.
Oh thanks for this info, didn't knew that. So this mean that if i used the ultra setting instead of default in Packps2, it will still make the same Archives?
Are you sure about that Sotho Tal Ker? Even the slightest difference in floating-point calculations across CPU's/OS's can cause the archive to be completely different. Unless 7zip uses only integers values. Do you know if that's the case?
Here is the link to packps2
http://www.mediafire.com/?cxbvztebq44
the file extension should be iso for it to work. if you have more then one image, u can either put them in a single folder or in subfolders and it will compress them all.
Oh thanks for this info, didn't knew that. So this mean that if i used the ultra setting instead of default in Packps2, it will still make the same Archives?
It will make the same archives when you use the same settings. Compressing with 7z ultra leads of course to higher compression vs. the normal 7z compression (because of Increased dictionary size). But every computer has to have enough resources to use such a large dictionary, else compression outcome might differ (when there is extensive paging for example).
Also you could use other advanced settings to improve compression.
Are you sure about that Sotho Tal Ker? Even the slightest difference in floating-point calculations across CPU's/OS's can cause the archive to be completely different. Unless 7zip uses only integers values. Do you know if that's the case?
Well, I am not completely sure (I did not look at the source of 7-zip), but so far packISO did work for many people on many different computers. Unless someone comes with an example that the file created is different, it stands as is (it's not a mathematical proof, but a natural ... it is right until someone disproves it). Of course everyone has to use the same 7-zip version.
10 2008-09-24 21:06:40 (edited by Sotho Tal Ker 2008-09-24 22:13:26)
Delete this post, since the server was misbehaving again :x
So, if 2 peole have the same dump and run it through packiso, they will get bit for bit identical output files no matter what computer/os they use? I'm a member of a well know retro gaming torrent tracker, and the 'masters' over their always pray that the only way for two people to get same checksums it to use torrentzip. Especially a 'torrent7zip' tool were called impossible due to 7zip not beeing able to produce identical files (and a too lousy source code to make it do so).
So far, files compressed with packiso have been identical for different people on different computers. Of course there is the possibility that there is an odd configuration where the result will be different, but this could happen with torrentzip aswell.
Those people should try it instead of praying. 
13 2008-09-25 05:34:34 (edited by ssjkakaroto 2008-09-25 05:45:05)
...but this could happen with torrentzip aswell
No, it couldn't 
Unless there was an error of course.
But seriously, from what I know of torrentzip, it was designed specifically to make identical results regardless of machine/OS (most probably by using integers only).
I thought the same could be done with 7zip, so when you said that PackISO got identical results on different machines I thought this was the case.
Compression algorithms are usually integer based.
So far same versions of 7zip used with the same options made identical results.
That is at least true for the Windows version of 7zip.
15 2008-09-29 13:41:08 (edited by topkat 2008-09-29 13:56:58)
But Winrar for instance gives me different results on different system. Tested with same settings, but once on a Turion Laptop with 2 Gig RAM and once with an old first gen. Pentium 4 with 512 MB. Torrentzip was specially developed with this aspect in mind, even an old Pentium 1 system should give you same results. I guess I will do some tests to proof 7zip.
If someday Daemon Tools will support compressed audio, this would be the perfect solution.
Those people should try it instead of praying.
It has been discussed several times, but sadly they are not so open minded for new ways....
16 2008-09-30 00:00:30 (edited by ssjkakaroto 2008-09-30 00:01:06)
I compiled p7zip 4.53 on a OpenBSD system (Pentium III 800MHz), used "touch -t 197912310900.00" on the file and compressed it with "7za a file.7z file.ecm"; then I used packiso on a WinXP SP3 system (AMD Sempron 3000+) on the same file.
Though the 7z size was the same on both machines, their md5 was different.
It's a shame that the guys who did torrentzip have no intention of doing a torrent7z...
Though the 7z size was the same on both machines, their md5 was different.
Can you do a binary compare to see how different those 2 files are? Maybe there is only a difference in the file header or the whole data stream is different.
I compiled p7zip 4.53 on a OpenBSD system (Pentium III 800MHz), used "touch -t 197912310900.00" on the file and compressed it with "7za a file.7z file.ecm"; then I used packiso on a WinXP SP3 system (AMD Sempron 3000+) on the same file.
Though the 7z size was the same on both machines, their md5 was different.It's a shame that the guys who did torrentzip have no intention of doing a torrent7z...
The problem probably is with time stamp and file atributes, as rmdtrasht.exe set the date to 1980/01/01 01:00.00 (i think it's (GMt) Greenwitch Mean Time) and removes all file atributes. Of course date must be set for: created, modified and accessed time stamps.
Sotho Tal Ker: The differences are only on the 2 first and 2 last offsets of the file
Probably touch is missing something that rmdtrash cleans.
Can the creater of PackPS2, edit the program to be made to compress things besides ISO? It just 7z the file right? Should work for anything? Hopefully someone can help me
i will add the remaining image format on Monday, i won't be going to office before that and the source code is on my office PC