Greaseweazel/SCP and IPF conversion questions
 

Brand new owner of a Greaseweazel v4 and attempting to preserve a handful of NTSC titles that to the best of my knowledge don't appear _anywhere_ (SPS/CAPS or TOSEC).

One of them is The Killing Game Show NTSC. In trying to dump this, I've come across something rather strange. If I dump to SCP with defaults, the dump doesn't work (in the latest WinUAE) - it reads from tracks 2 to 6, then loops back and does it again to infinity. Booting the physical floppy from WinUAE works fine, so it seems pretty obvious that it's likely a weak-bits protection method.

Here's the strange thing - the default for gw is revs=3. This dump attempt does _not_ work:

gw.exe read --drive=B KillingGameShow_NTSC_Disk1.scp

but this one *does*, _consistently_:

gw.exe read --drive=B --revs=3 KillingGameShow_NTSC_Disc1.scp

even though they should be the same dump method (and indeed, the resulting file sizes are very close to the same). What's up with that?

Next, conversion to IPF format...I'm aware that the CAPS library has very limited weak-bits support (which is as I understand it the reason why even KGS PAL doesn't appear in IPF). Is there any means at all of doing so manually? I ask because my target supports IPF but not SCP unfortunately.

Sorry for the newbie dumper questions...my intentions are good! =) (I also acquired Dragon's Lair NTSC for preservation but sadly disk 1 appears to be damaged, or at least neither dumps nor direct floppy boot work after the initial stage, and multiple dump attempts resulted in vastly different numbers of flux readings initially that prevented boot at all, so I think the disk is screwed.)

If I can ever figure all this out, more will follow and be happy shared for long-term preservation, obviously.

5 revs is recommended for an archive quality image.

Keir Frasers' Disk Utilities pack on Github converts SCP to IPF for the set list of titles it has - not all are covered yet. There is a thread here "Creating your own IPF's" where a pre-compiled Disk Utilities is regularly updated by "ACD2000" - one note to this is apparently only Kyroflux software can make a writable IPF on all titles atm. Keir seems to be focusing on emulation use so not all outputs are suitable for disk use.

You could clean and re-write your dragon's lair disk(s) from images :
http://ftp2.grandis.nu/turran/FTP/Th...onsLairNTSC%20[Unofficial%20IPFs%20of%20Dragon's%20Lair%20NTSC%20for%20Demoniac].7z

Killing Game show is not using any weak bits protection. It uses a longtrack as copy protection plus a custom special encoding scheme with very long tracks.

Your dump is simply faulty.

Your disks possibly need to be cleaned before being dumped.

Please dump in kryoflux mode with your Greasleweasle, and send me the dumps.

Make the folder KGSx_NTSC beforehand then type :

GW read KGS1_NTSC\Track.raw --revs=5 --tracks=c=00-83

@All

Thank you so much for all the help (and education)!

Now that I better know what I'm actually doing (particularly with disc-analyze - I've compiled from git with IPF support), things are working very well!

I have two copies of KGS NTSC, and one of the discs does indeed appear to be faulty.

I've done 5-rev dumps and IPF conversions (with logging) that I'd be happy to share with the community - how can I go about doing so?

@dlfrsilver - my confusion stemmed around why the SCP dumps work differently if you specify revs=3 explicitly versus not specifying at all. Both should end up with the same dump, because they should both be 3 revs, but the one using default settings (i.e. revs is implicit) *NEVER* boots properly, and the one with 3 revs set explicitly *always* boots properly. That's why I assumed it was a weak bits issue...now I honestly have no idea. It was purely a matter of intellectual interest, the 'real' preservation dumps are proper and well understood.

KGS NTSC IPFs in the Zone, will add raw SCP dumps tomorrow

This is indeed very strange.
If it happened *not* consistently, it could be caused by bad reads sometimes, but since you always have non-working images with the first line and working images with the second one, maybe it's a gw.exe bug... :nervous

It's better to do KF RAW dumps, if possible (more reliable format than SCP).
Could you produce one? (5 revs, tracks 0..83, 168 resulting files)

All set, full KF raw track dumps with IPF and analysis in the zone (note disk 1 from set 2 looks bad)

Your dumps are all good. They load with no problem.

My advice : install them under winuae with whdload. The rawdic slave will tell you if any track is wrong.

Sorry - 'bad' in the sense that it doesn't match the expectation of the CAPS/SPS definition. It could be an alternate, but I don't know what changed.

Killing game show is unsupported by the SPS tool, due to the protection used.

Sorry - I really meant disk-analyse, which I thought was a descendent of the SPS tool (but I could be entirely wrong on that!).

One more interesting datapoint - my dump of the same disk with DrawBridge won't even boot, so I think there really is something (slightly) wrong with the disk that Greaseweazel could deal with. Granted, DrawBridge can only do 1 rev, maybe that contributes.

i don't know Drawbridge, but clearly, Killing game show use a very specific format that is not MFM, with a bigger storage capacity.

Use Greasleweasle or Kryoflux to dump such disks.