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bsnes v0.038 released 
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h4tred wrote:
Is it even worth the effort to preserve titles like Super Noah's Ark 3D?

How do you know for sure it isn't? Another example for artificial limiting, if you ask me... :o

byuu wrote:
It's a bit much.

Sure. I don't mind adding clutter (to programs and threads), which can always be ignored IMO, if it means more options. Seems I'm the most extreme one in that regard, which is fine. :wink:

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Wed Jan 07, 2009 3:53 am
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But wouldn't it make sense to archive those that are of at least some merit?

Sure, its artificial limiting, but really, is there a point to document all the ROMs that have no real historical value?


Wed Jan 07, 2009 4:19 am
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byuu wrote:
The longest code I can find on gamegenie.com is for FF6, four parts.

Try BSFree. :P Here's a code for Super Mario Kart with 5 codes...

Multi-Cam Mario Code:
1A3E-CDA4
5E38-4DD4
C4EB-CDA4
34EB-CDA4
E9EB-CDA4

Here's a code for Super Ghosts & Ghouls...

Infinite Armor/Invincibility & Armor Modifier:
C2EC-0F08
C22B-AFD9
C22E-AD09
622A-D460
C228-DFA5
##C8-A7D1
##2B-D461

7 codes, ouch. 8 may be a safe bet for a limit though, if not that then 6 will suffice.

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Wed Jan 07, 2009 5:12 am
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blargg wrote:

Nach wrote:
Maybe if you did that, you won't need gamma ramp any more.

Now that I've read more about gamma and video signals, I can be more authoritative.

You knew I was kidding, right?

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Wed Jan 07, 2009 5:51 am
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h4tred wrote:
But wouldn't it make sense to archive those that are of at least some merit?

Sure, its artificial limiting, but really, is there a point to document all the ROMs that have no real historical value?


The main problem is that a judgment of "historical value" is subjective. On top of that, this subjectivity can flip-flop to suit whatever era currently desires the judgment. Right now we don't see Super 3D Noah's Ark as anything important, but when we're deceased and there's a new, more archaeologist-perspective-oriented set of ROM collectors, they may see things differently.


Wed Jan 07, 2009 6:22 am
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blargg wrote:
The question for the SNES is what gamma it applies when encoding composite and s-video outputs (and perhaps RGB). If it uses none, then proper conversion to the linear RGB values of the light leaving the display's surface requires applying a 2.5 gamma. If the SNES uses 0.5, then conversion requires applying a 1.25 gamma.

After an informal test of displaying a gray ramp, it looks as though the SNES encodes the video signal linearly, thus resulting in a gamma applied to the raw RGB values by the display. So SNES images in an emulator should look more or less correct on a PC without the emulator doing any gamma correction. In retrospect, this is the only approach that makes sense. Like with the PC, you want the RGB values in the framebuffer to have gamma applied by the display device.

Quote:
3. SNES applies no gamma when encoding video. So we need to apply a 2.5*0.45 = 1.125 gamma.

This one.


Wed Jan 07, 2009 6:49 am
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DataPath wrote:
Am I doing something wrong?


You are comparing one of the modified versions (cannot tell which one) with the original, not with the other modified ROM.


Wed Jan 07, 2009 6:51 am
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h4tred wrote:
Quote:
Now.... if we can't even keep track of Neil Armstrong's first step, what chance does Super Noah's Ark 3D have?


My question is: Is it even worth the effort to preserve titles like Super Noah's Ark 3D? To me, even the name suggests its not worth saving. :?

Probably not.

It's only notable for being the only unlicensed SNES game known to exist.
Apparently it's just a graphics hack of Wolfenstein 3D, though no one knows if Wisdom Tree got the license or just pirated it.

It was just the first relatively obscure one that came up.




I know for a while, I couldn't prove Realm existed, despite having played the cartridge.
No one had heard of it, and it wasn't in the GoodSNES set, so... obviously I HAD to be crazy.
...
Realm isn't very good either.


Wed Jan 07, 2009 7:59 am
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Alright, you've made your case, ecst (though the motivator is still manufactured). What do you suggest we come up with to identify these files? Is there an existing hash method with which you wouldn't be able to do what you just did?

Quote:
The main problem is that a judgment of "historical value" is subjective. On top of that, this subjectivity can flip-flop to suit whatever era currently desires the judgment. Right now we don't see Super 3D Noah's Ark as anything important, but when we're deceased and there's a new, more archaeologist-perspective-oriented set of ROM collectors, they may see things differently.


That's true, but the chief focus of any preservation effort is going to be on commercial released of licensed material. Everything else is infinitely creatable, my hands are full as is. I really don't draw a distinction between Super Noah's Ark and something some guy made in his basement. The only difference is one had the resources to put it on a cart and sell it (illegally) and one didn't. That said, it's true that Super Noah's Ark > Pit Fighter.


Last edited by FitzRoy on Wed Jan 07, 2009 8:06 am, edited 1 time in total.



Wed Jan 07, 2009 8:00 am
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FitzRoy wrote:
That's true, but the chief focus of any preservation effort is going to be on commercial released of licensed material. Everything else is infinitely creatable, my hands are full as is. I really don't draw a distinction between Super Noah's Ark and something some guy made in his basement. The only difference is one had the resources to put it on a cart and sell it (illegally) and one didn't.
Illegally?
You'd better cite what section of US law makes this illegal.

Don't go PATRIOT act on me, since it didn't exist in the early 90s.


Wed Jan 07, 2009 8:03 am
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It's legal to make and sell games for a system without obtaining licensure? Then why the hell did anybody bother to pay licensing fees?


Wed Jan 07, 2009 8:08 am
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FitzRoy wrote:
It's legal to make and sell games for a system without obtaining licensure? Then why the hell did anybody bother to pay licensing fees?
Because it's HARD, in most cases.

The Nintendo lockout chip was a bitch to crack.

And in the NES days, Nintendo blackmailed retailers.
If you carried unlicensed carts, you got a friendly letter about how you were damaging Nintendo's reputation for quality. And then your holiday shipments mysteriously got delayed.


EA produced unlicensed Genesis games at first too.
They expended the (minimal) effort to "crack" the Genesis. When Sega redesigned the Genesis hardware to fix that crack, they cut EA a deal to get them on a license. Among other things, it included a concession that let them use a non-standard cart shell.


GameBoy I've got no explanation for. It's as trivial to "defeat" as the first-run Genesis.

My best guess is momentum from the NES blackmail days has made retailers wary of unlicensed software.
NES had a whole slew of them, Genesis had 3, SNES had 1...

Could also just be that post-NES, hardware manufacturers have generally been more willing to work with developers instead of against them.
Having the backing of the hardware manufacturer for advertising and distribution makes life simpler.



It's legal, though. Or was.
DMCA(why did I say PATRIOT earlier?) may make it illegal, since the copy-protection and license-management techniques go hand-in-hand.


US copyright law makes no distinction between computers with publisher lockout and those without them. They're just computers.


Wed Jan 07, 2009 8:28 am
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FitzRoy wrote:
What do you suggest we come up with to identify these files? Is there an existing hash method with which you wouldn't be able to do what you just did?

Wait until SHA-3 comes out?

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Wed Jan 07, 2009 9:08 am
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SHA-256 would have to suffice for now.


Wed Jan 07, 2009 10:22 am
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Yeah Nintendo's "Iron-Grip" days where they blacklisted retailers. I remember one of their stunts to get back at Tengen was they went over to Russia and greased some commy palms to let them release Tetris, even though Tengen had already cut a deal. When Tengen tried to sue, the Russians, now with pockets stuffed with Nintendo dollars, basically said "snooze you lose".


Wed Jan 07, 2009 11:22 am
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Gil_Hamilton wrote:
(Snipped. summary: Everyone thinks it's illegal because Nintendo doesn't like it)


And just before anyone goes to ask, the legal case which set precedent for such a matter is Atari Vs. Activision. And such a case is why Nintendo never truly could get rid of Sachen (Various titles) or Gamemasters (Game Genie, Dizzy series) - these were able to circumvent Nintendo's lockouts in ways that did not infringe upon any copyrights (the idea of doing this, also, is what many consider to be the difference between indie/homebrew console devvers for Wii/Dreamcast/etc. and game pirates that would just hardmod the consoles.)

The fact that people seem to get the false idea that unlicensed games were by their very existence were illegal only goes to show even more that the games need better preservation - for the sake of improving our knowledge. Without the data, false assumptions arise, and thus generates a flawed research into the console's history - thus defeating the purpose of archival, which is to keep the truth known.

I'm able to sympathize with this because I myself am frustrated at the lack of preservation for games for "unpopular" systems. Obviously the Satellaview was brought up earlier - so little was known about that for a long time because only recently have Japanese been able/generous enough to display their most helpful information.
How's about that Sega Pico as well? Talk down about edutainment all you want, those are still Sega-licensed games. I'm rather saddened that even after a preliminary emulator was developed, there has not been a large-scale effort to dump it's Storybooks. And then there's the Beena, which is the -followup- to the Pico.
And not to mention how I've been looking at various websites for archiving info about gaming obscurities, and find fascinating and sometimes shocking things every day. Just last week I checked out the blog about the Phillips CD-i and I find myself thinking about that Golgo 13 game.


Wed Jan 07, 2009 5:10 pm
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Noah's super 3d ark and a half is as legal as pro action replays, seeing as it's not cracking any licensed lockout chip but uses the piggyback slot cart's.

Re: multiple cheats
... add a field for 'number of cheats'... and use a clicky +/- box thing to scroll through all of them. Too hard ?

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Wed Jan 07, 2009 8:12 pm
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ecst wrote:
DataPath wrote:
Am I doing something wrong?


You are comparing one of the modified versions (cannot tell which one) with the original, not with the other modified ROM.


I thought the objective was to make a fake that looks like a real, not a fake that looks like another fake.

Coming up with two files with matching hashes is a LOT easier than coming up with a file with a specific hash. What you did is called a birthday attack, which gives you a 75% chance of a 20-order-of-magnitude improvement in generating a collision - but that only works if you have control over BOTH inputs.

In other words, you used a shortcut that doesn't apply to the problem at hand.


Wed Jan 07, 2009 8:32 pm
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DataPath wrote:
I thought the objective was to make a fake that looks like a real, not a fake that looks like another fake.


The objective was to show that MD5 plus CRC32 is not any more secure than MD5. And I hate to quote myself, but:

ecst wrote:
As soon as an MD5 preimage attack becomes known (and I have little doubt that will happen in the next 5 or 10 years), the modified versions can just as easily be arranged to have the same MD5 hash as the original.


DataPath wrote:
Coming up with two files with matching hashes is a LOT easier than coming up with a file with a specific hash. What you did is called a birthday attack, which gives you a 75% chance of a 20-order-of-magnitude improvement in generating a collision - but that only works if you have control over BOTH inputs.


It is actually not a birthday attack, but another generic type of collision attack, which would also extend to preimage attacks, given one for MD5.

DataPath wrote:
In other words, you used a shortcut that doesn't apply to the problem at hand.


I only intended to practically verify the claims made by myself earlier.


Wed Jan 07, 2009 8:46 pm
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Gil_Hamilton wrote:
GameBoy I've got no explanation for. It's as trivial to "defeat" as the first-run Genesis.


GameBoy was their moment of legal brilliance, basically. The 'protection' in this case was a copyrighted and trademarked logo in bitmap form, so by having that fixed byte sequence in your ROM, you had to fight uphill against copyright law AND trademark law instead of just them basically going, "We didn't say they could, WAH!" like with the NES lockout chip.

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Wed Jan 07, 2009 9:30 pm
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FirebrandX wrote:
Yeah Nintendo's "Iron-Grip" days where they blacklisted retailers. I remember one of their stunts to get back at Tengen was they went over to Russia and greased some commy palms to let them release Tetris, even though Tengen had already cut a deal. When Tengen tried to sue, the Russians, now with pockets stuffed with Nintendo dollars, basically said "snooze you lose".

Actually, the Tetris licensing issue was a mess to start with.

Atari Games(and by extension TEngen got their license from a european guy that got a license from the russians to make PC versions.
Nintendo got a license from the russians to make console versions.

The stuff I've read makes it sound like the european guy was trying to screw everybody, and he never had console(or arcade) rights to start with. Atari Games got burned for assuming the guy was being honest.


They then created Klax, in an attempt to provide themselves with an in-house puzzle game they KNEW they could sell.
Which is actually a pretty neat game, but it lacks the simplicity of Tetris.


WolfWings wrote:
Gil_Hamilton wrote:
GameBoy I've got no explanation for. It's as trivial to "defeat" as the first-run Genesis.


GameBoy was their moment of legal brilliance, basically. The 'protection' in this case was a copyrighted and trademarked logo in bitmap form, so by having that fixed byte sequence in your ROM, you had to fight uphill against copyright law AND trademark law instead of just them basically going, "We didn't say they could, WAH!" like with the NES lockout chip.

Actually, since it's a mandatory requirement to get a game to run, it's exempted.

Sorta like how putting the ASCII codes for "SEGA" in a Genesis game's header is safe, albeit more extreme.
...
Actually, it's pretty much a direct copy of the Genesis scheme.


See Sega vs Accolade.
http://digital-law-online.info/cases/24PQ2D1561.htm

Sega lost, and the use and display of their trademark was found to be fair use, setting the precedent that would apply to unlicensed Gameboy software if any existed.

" In the case before us, Accolade’s identification of the functional requirements for Genesis compatibility has led to an increase in the number of independently designed video game programs offered for use with the Genesis console. It is precisely this growth in creative expression, based on the dissemination of other creative works and the unprotected ideas contained in those works, that the Copyright Act was intended to promote."

and

"In any event, an attempt to monopolize the market by making it impossible for others to compete runs counter to the statutory purpose of promoting creative expression and cannot constitute a strong equitable basis for resisting the invocation of the fair use doctrine."

The opinion of the court is that copyright law is explicitly NOT intended to allow manufacturers to restrict availability of creative works.



"A product feature thus is functional “if it is essential to the use or purpose of the article or if it affects the cost or quality of the article.” The Lanham Act does not protect essentially functional or utilitarian product features because such protection would constitute a grant of a perpetual monopoly over features that could not be patented. Even when the allegedly functional product feature is a trademark, the trademark owner may not enjoy a monopoly over the functional use of the mark. "

And the Nintendo bitmap is fair game, despite being a trademark, because it is a functional part of Gameboy software. You can't make a Gameboy game without it.


Wed Jan 07, 2009 11:00 pm
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ecst wrote:
DataPath wrote:
In other words, you used a shortcut that doesn't apply to the problem at hand.


I only intended to practically verify the claims made by myself earlier.


Congratulations. You've verified that a problem exists in a situation different than the one under discussion.


Wed Jan 07, 2009 11:13 pm
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DataPath wrote:
Congratulations. You've verified that a problem exists in a situation different than the one under discussion.


How is this response helpful? I don't know how he could have made his point more clearly: combined collisions are possible by only modifying a few bytes. Eventually, it will be possible, nay trivial, to apply this attack to existing images as well.

That the emulation scene in general has no concept of the long-term is abundantly clear. We don't see eye to eye here, granted.

Logically, lossless compression of the source data is the only way we can 100% correctly identify a file with less bits than the original file itself. So should we just give up? Settle for SHA-2 and say good enough? Or keep looking? Surely, someone out there has to be working on the problem of long-term digital data validation.


Thu Jan 08, 2009 12:18 am
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byuu wrote:
DataPath wrote:
Congratulations. You've verified that a problem exists in a situation different than the one under discussion.


How is this response helpful? I don't know how he could have made his point more clearly: combined collisions are possible by only modifying a few bytes. Eventually, it will be possible, nay trivial, to apply this attack to existing images as well.


Helpful? Not really. Unnecessarily adversarial? Maybe a little.

But the point he made is unrelated to the current discussion. What he proved is that you can find an m and an n where f(m) = f(n) fairly trivially. In that situation, you basically shrink the key space from 2^n to 2^(n/2). He says what he did was not a birthday attack, but either way, it still mathematically reduces to the birthday problem.

Although, now that I think about it, in a way, the birthday problem DOES apply, because if someone wanted to pollute the pool, they don't necessarily have to find a two-dimensional collision for a specific ROM in the database - they can search for collisions for ANY ROM in the database. The larger the database is, the better the chances of a collision.

So if the goal of someone were to simply pollute the pool with as many bad ROMs as possible, playable or not, then they do have freedom to choose both m and n. It's not a 2^(n/2) improvement, but it's still an improvement.

I will concede that my conception of the problem was too narrow. A pre-imaging vulnerability isn't necessary since there are enough different hashes available in the database to make birthday-type attacks useful (at least with a keyspace as small as md5 - the sha2 family has a keyspace large enough that it would take an insanely large number of ROMs to provide a decent chance of a birthday-type collision).

One thing I've often wondered about - wouldn't a hash/filesize tuple be significantly more secure than just the hash? A hash collision with the same file size becomes extremely improbable, and the smaller the file, the more likely it is to be impossible.

for example, given MD5("a") = 0cc175b9c0f1b6a831c399e269772661, you can guaranteed find a collision. But to find a collision that is 1-byte long would be impossible.


Thu Jan 08, 2009 4:27 am
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Quote:
So should we just give up?


I don't see the futility of what we've done so far. There is no motivating factor in spoofing purely to deceive, which is exactly why everything I've dumped has, bit-for-bit, matched files being passed around against supposedly weak identification methods. This won't change in the long-term. There is no hope for the human species if someone takes the time to do this 50 years from now, let alone today.

Quote:
Settle for SHA-2 and say good enough?


Surely, filesize+SHA-2 is plenty secure for our uses, though I still refuse to migrate to it until a multi-system rom manager and database creator actually supports it. I was going to try and get one of my friends to make a better one (he's taking programming classes right now), but if you want to take a break from bsnes and do it, that's cool, too :wink:

I'm going to use photoshop to create a sort of graphical mockup, and then write about the behavior and formatting of the database files it loads/creates. Maybe you can look at it and tell me how hard it would be for someone to make?


Thu Jan 08, 2009 5:23 am
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