Post subject: Information on ROMs on this site
Skilled player (1889)
Joined: 4/20/2005
Posts: 2160
Location: Norrköping, Sweden
Before making a TAS you need to decide what ROMS you are to use. For a lot of games the choise is simple, you use the english version of the ROM, such as Mega Man 4 (U).nes. If the ROM has a [!] in the name, that's just good since that means that it is a "Verified Good Dump". My question is if it would be a good idea to have a page on this site that gives information on what all the symbols in a ROM-name means and what symbols that are recommened that the ROM you use for a TAS have. For someone who is about to make their first TAS, it sometimes happens that they pick a bad ROM dump. This new info on all the symbols in ROM-name could be applied to the page http://tasvideos.org/Rules.html#the_rom_must_be_good_ or perhaps even get a page on its own. I think that a lot of people that are thinking about making a TAS don't know, for example, what PRG0 in the ROM-name means (I know I don't know what PRG means). Another thing that is quite confusing is whether you should use the 1.0 or 1.1 version of the ROM. Is there a way a way to tell the difference between these ROM-dumps? I think that it would be a good idea to have information about these things on the site, so that people know for sure what ROM that it's recommended that they use (such as PRG-version 1.X - version). What do all of you think about this? Bisqwit: If you don't think that this thread suits "Off topic" you are free to move it. I thought about where to post this thread and decided to post it here, but perhaps you think it's better to put it somewhere else.
Post subject: Re: Information on ROMs on this site
Editor, Active player (296)
Joined: 3/8/2004
Posts: 7469
Location: Arzareth
This is a gray area and my policy is "no". Reason: The naming system of the ROMs you speak of is not an official one, but one devised by ROM piraters. I do not wish to make the site look like we support it. At most, we can link to a document that explains those symbols in the ROM names. Someone can do that (I don't remember where those documents were).
Skilled player (1889)
Joined: 4/20/2005
Posts: 2160
Location: Norrköping, Sweden
Bisqwit wrote:
This is a gray area and my policy is "no". Reason: The naming system of the ROMs you speak of is not an official one, but one devised by ROM piraters. I do not wish to make the site look like we support it.
Allright then, it's probably better to leave it then. I didn't know that it was devised by ROM piraters. Biqwit wrote:
At most, we can link to a document that explains those symbols in the ROM names. Someone can do that (I don't remember where those documents were).
I know of such a page. Here is the text: Standard Codes: [a] - Alternate - Bad Dump [BF] - Bung Fix [c] - Cracked [f] - Other Fix [h] - Hack [o] - Overdump [p] - Pirate [t] - Trained [T] - Translation (Unl) - Unlicensed [x] - Bad Checksum ZZZ_ - Unclassified [!] - Verified Good Dump (???k) - ROM Size Special Codes: [C] - Color GameBoy [S] - Super GameBoy (M#) - Multilanguage (# of Languages) [M] - Mono Only (NeoGeo Pocket) (PC10) - PlayChoice 10 (NES) (1) - Japan (Genesis) (4) - USA (Genesis) (5) - NTSC Only (Genesis) (8) - PAL Only (Genesis) (BS) - BS ROMS (SNES) (ST) - Sufami Turbo (SNES) (NP) - Nintendo Power (SNES) (Adam) - ADAM Version (Coleco) (PAL) - PAL Video Country Codes: (A) - Australian (C) - Chinese (E) - Europe (F) - French (FN) - Finland (G) - German (GR) - Greece (HK) - Hong Kong (I) - Italian (J) - Japan (K) - Korean (NL) - Dutch (PD) - Public Domain (S) - Spanish (SW) - Sweden (U) - USA (UK) - England (Unk) - Unknown Country (-) - Unknown Country
ventuz
He/Him
Player (123)
Joined: 10/4/2004
Posts: 940
you shouldnt be linking to that... maybe rather than linking to that, copy and paste those thing here?
Player (71)
Joined: 8/24/2004
Posts: 2562
Location: Sweden
What I thought was more interesting to know is what differs a rom of the same game from another? Like a PRG0 and PRG1 version etc. What was changed in the game and so forth. Perhaps someone could investigate further and make a super-huge DB about it? =)
Editor, Active player (296)
Joined: 3/8/2004
Posts: 7469
Location: Arzareth
Highness wrote:
Like a PRG0 and PRG1 version etc. What was changed in the game and so forth.
Yeah, it depends on game. In Super Mario Bros for example, some levels were minorly tweaked. For instance, the death hole (shown in the image) in the swimming levels above the last pipe was removed, and the stairs in the beginning of 8-1 were somehow changed as well. (This animation does not demonstrate the death hole, but the swim of death.)
Skilled player (1889)
Joined: 4/20/2005
Posts: 2160
Location: Norrköping, Sweden
ventuz wrote:
you shouldnt be linking to that... maybe rather than linking to that, copy and paste those thing here?
Yes, you are right ventuz... I fixed it now though. Sorry about that.
Former player
Joined: 3/30/2004
Posts: 1354
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Highness wrote:
What I thought was more interesting to know is what differs a rom of the same game from another? Like a PRG0 and PRG1 version etc.
By definition, it's the location of the programming (rather than sprite data) in the ROM. PRG0 has the code as the first thing, PRG1 has it in the second thing. So there doesn't neccessarily have to be any visible changes in the game.
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Player (71)
Joined: 8/24/2004
Posts: 2562
Location: Sweden
Ok. So do you guys think my idea suck or is worthless?
Joined: 10/3/2004
Posts: 138
Rather than worrying about Good* names, we should worry about CRC32 checksums of ROMs. That way, even if you dumped your own carts, you would know that you have exactly the right one. Since I don't know of anyone else who seems to care about checksums, it wouldn't necessarily have the side-effect of 'promoting' illegal ROM distribution.
Skilled player (1889)
Joined: 4/20/2005
Posts: 2160
Location: Norrköping, Sweden
Yes, I too think that's a pretty good idea, LocalH. Perhaps there could be a column in the "authors comments" where you could write the ROM's checksum? I think that it's good to mention the checksum of the ROM that was used for the TAS, this way people know if they found the right ROM. At least I don't see any harm in doing it. Even if the authors submission does mention the ROM of the name, all ROMs of the same name aren't the same ROM. I don't see how this could promote illegal ROM distribution. But if it in any way does, it's probably a bad idea and should be skipped. By the way, is it only NES ROMs that have checksums or does all ROMs have it?
Emulator Coder, Skilled player (1301)
Joined: 12/21/2004
Posts: 2687
Randil wrote:
By the way, is it only NES ROMs that have checksums or does all ROMs have it?
You can calculate a checksum for anything, it doesn't even have to be a ROM. Although different ROM formats have different types of checksums that are used for them in practice.
Player (36)
Joined: 9/11/2004
Posts: 2624
However, don't the rerecording emulators we use automatically calculate and store the checksums in the movie files? I know FCEU, snes9x, and VBA do...
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Joined: 10/3/2004
Posts: 138
The only system I can think of off-hand that includes a checksum in the ROM is the Genesis - the two bytes directly following the product ID is the checksum (for example, Sonic 2 is D951 for the most common rev 01 version), and it's up to the game to checksum itself (many games don't bother - I recently hacked Wiz 'n' Liz to interlace mode 1 and didn't have to bypass any checksum verification). But this isn't a CRC32, so I don't think it would be so useful in this instance, since you need one system that works for all ROMs. Either use a CRC32 or an MD5 hash, I would think either one would suffice. If emulators already put the CRC32 in the movie files then it would probably be best to just go ahead and use that, then you could literally just extract the checksum from the movie file.
Emulator Coder, Skilled player (1301)
Joined: 12/21/2004
Posts: 2687
Most console systems include checksums in the ROMs, but yeah, the thing that would be most useful is actually the CRC32 which probably isn't in the ROM. VBA-rerecording, FCEU (pretty sure), and (only some) Snes9x movie files already have the CRC32 stored directly in them.
Joined: 10/3/2004
Posts: 138
I know for a fact that FCEU stores the CRC32, because it tells you if there is a discrepancy (for example, I used a hacked SMB1 ROM with SMB2j graphics and it showed my ROM's CRC32 in red).
Editor, Active player (296)
Joined: 3/8/2004
Posts: 7469
Location: Arzareth
LocalH wrote:
I know for a fact that FCEU stores the CRC32
In fact, it stores MD5-sum.
Joined: 10/3/2004
Posts: 138
Whoops, I'm not a checksum expert. Which checksum do the other emulators use? If they all use the same one then it would make this a lot easier. Either that or just settle on a single checksum for each system then just store it in your database as a raw hex string.