[game_preservation] Kotaku: Videogame History Museum Kickstarter short on funds

[Christian Bartsch]

Henry, thanks for the read! I saw some familiar names there that I already got in touch with over KryoFlux. ;)

On page 52 in the second paragraph ("Copyright") I found this: "This is typically done by creating an image of the original media; that is, making an exact, bit-for-bit replica of the disk that can then be mounted from the hard drive or burned to a fresh disk (e.g. an ISO or IMG file)" and I would have to object.

While I agree that a bit for bit replica of the disk (or disc) is what one would want, both image formats named - ISO and IMG - are unable to carry the information that might be present on the source. To my understanding e.g. an ISO can not hold the protection data used by e.g. SecuROM or CD Cops. The same applies for IMG files, which are sector dumps only. You can only store decoded data in them, thus eliminating everything that does not fit the structure of the IMG (=everything that is non-standard, like copy protection).

I think we really have to demo this with a forensic dump of some game sooner or later. I know hundreds of games that use something that won't fit into any standard container, e.g. a recording density based Rob Northen Copylock. The only chance you'd have for such data present in an IMG (or ADF if we'd be speaking about an Amiga game) would be the removal of the protection, thus cracking it. Since many of the later games on Amiga and Atari with Copylock use a trace vector decoder (http://en.wikipedia.org/wiki/Trace_vector_decoder) - basically a hardware assisted way to decrypt the current instruction in memory only and leave the rest obfuscated - this would need a pretty skilled person. Taking into account that many games we prepared to fool crackers and had additional checks that would see if the Copylock is still in place, this is a demanding task.

The only alternative is reading and preserving disks at the bit-level, taking note of everything, describing (scripting) it and making sure it will be interpreted correctly. The only way to achieve this is to preserve mastering data, data that describes how a disk should be written, not how it was read. This is why we spent ten years on IPF (Interchangeable Preservation Format), which already supports Amiga, Atari ST, IBM PC, Spectrum and Amstrad CPC. Other platforms, like C64, are in development, but we needed to develop a 5.25" drive (to be precise a modification) first that can read disks the way they were produced - in one single pass, with a drive that physically can access track -8, to access track 0 on the flip side (where all tracks are shifted by -8 tracks).

Having said that we are eager to exchange information and help getting more titles preserved the right way...

--
Christian Bartsch
The Software Preservation Society
http://www.softpres.org

On 23 Aug 2011, at 18:30, Henry Lowood wrote:


> Just a reminder: The Preserving Virtual Worlds final report goes into some of the issues that have been discussed here.  I think we came out in pretty good shape on transfer, ingest, metadata control, etc.  Not so far on capture, imaging and access, and the Second Life case and machinima conference told us plenty about the difficulties introduced by "soft" issues such as privacy concerns, legal environments, etc.

> https://www.ideals.illinois.edu/handle/2142/17097

> 

> Henry

> 


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