ROM image
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A ROM image, or simply ROM, is a computer file which contains a copy of the data from a read-only memory chip, often from a video game cartridge, a computer's firmware, or from an arcade game's main board. The term is frequently used in the context of emulation, whereby older games or computer firmware are copied to ROM files on modern computers and can, using a piece of software known as an emulator, be run on the newer computer.
ROM images are also used when developing for embedded computers. Software which is being developed for embedded computers is often written to ROM files for testing on a standard computer before it is written to a ROM chip for use in the embedded system. At present, this article deals mainly with the use of ROM in relation to emulation.
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[edit] Usage of ROMs
[edit] Changing meaning
ROM chips, while still in use, have been replaced in many instances by optical media such as CD-ROMs and DVD-ROMs, magnetic media such as hard disks and magnetic tapes and, more recently, Flash Memory chips. However, the term ROM is commonly misused to cover many of these newer media so, for instance, a computer game copied from a magnetic tape may also be referred to as a ROM. Images copied from optical media are also called ISO images, after the standard file system for optical media, ISO 9660. Many ROMs used by emulators, of particular note, console emulators are not true images of the ROM chips present on the Cartridge PCBs. They are often modified to allow easier functionality in emulators through methods such as combining the images from multiple ROM chips, or adding header information.
[edit] Dumping ROMs
ROMs can be copied from the read-only memory chips found in cartridge-based games and many arcade machines using a dedicated device in a process known as dumping. For most common home video game systems, these devices are widely available. Dumping ROMs from arcade machines, which in fact are highly customized PCB's, often requires individual setups for each machine along with a large amount of expertise.
Creating ROMs from other media is often considerably easier and can often be performed with off-the-shelf hardware. For example, the creation of ROMs from games stored on magnetic tapes (from, for example, the Sinclair ZX80 computer) generally involves simply playing the magnetic tape using a standard audio tape player connected to the line-in of a PC sound card. This is then recorded to an audio file and transformed into a ROM file using a simple program. Likewise, many CD and DVD games may be copied using a standard PC CD/DVD drive.
[edit] Copy prevention mechanisms
While ROM images are often used as a means of preserving the history of computer games, they are also often used to facilitate the unauthorised copying of modern games which are still commercially viable. Seeing this as potentially reducing sales of their products, many game distributors have incorporated features into newer games which are designed to prevent copying, while still allowing the original game to be played. For instance, the Nintendo GameCube used a non-standard 8 cm DVD-like optical media which for a long time prevented games from being copied to PCs. It was not until a security hole was found in Phantasy Star Online Episode I & II that GameCube games could be successfully copied to a PC.
[edit] ROMs and preservation
The lifespan of digital media is rarely great. While black-and-white photographs may survive for a century or more, many digital media can become unreadable after only a decade. This is beginning to become a problem as early computer systems may be, at the time of writing, fifty or sixty years old while early home video consoles may be nearing thirty years old. Due to this aging, there is a significant threat that many early computer and video games may not survive without being transferred to new media. So, those with an interest in preservation are actively seeking older arcade and video games and attempting to dump them to ROMs. When stored on standardised media such as CD-ROMs and DVD-ROMs, they can be copied to future media with significantly reduced effort.
The trend towards mass digital distribution of ROMs, while potentially damaging to copyright holders, may also have a positive effect on preservation. While over time many original copies of older games may deteriorate, be broken or thrown away, a copy in ROM form may be distributed throughout the world, allowing games which would otherwise have been lost a greater chance of survival.
[edit] Collecting ROMs
Like many other items such as stamps and coins, ROMs are also collected by many people. The motives for doing this vary from a desire to preserve the history of computer and video games to obsessive collectors. Those who desire to collect all ROMs have been derided by the team behind the MAME emulator as PokéROMs, in a reference to the Pokémon fad. PokeROM can also refer to "Pocket ROMs" as Pokemon refers to "Pocket Monsters"; since with the advent of the GP2X and SecureDigital cards, people can now have an entire library of old games in their "pocket".
Given this desire by many people to collect ROMs, there are many projects on the internet which dump ROMs, catalogue them or provide tools to verify the correctness and completeness of ROM collections. For instance, the TOSEC and Good Tools projects produce regularly-updated databases of games and other software for various old computers and video games consoles.
According to some, the "Holy Grail" of ROM collecting is the NES Nintendo World Championship 1990 cartridge ROM image, of which there were only 127 original cartridges in the world. However, the game has since been dumped as a ROM Image and copies are much more widely available.
[edit] Internet distribution of ROMs
The trading of ROMs over the internet is extremely widespread. Many methods are used for such distribution, including:
- HTTP (hypertext transfer protocol) and FTP (File Transfer Protocol)
- BitTorrent
- Direct Connect hubs
- eMule
- IRC DCC
- Usenet binaries
Although the large size of games for recent consoles makes the distribution of more than one game at a time impractical, it is often the case for older consoles that many thousands of games can be distributed together as a collection. For example, the entire Good2600 set of 2,687 Atari 2600 games could be downloaded in around two minutes over a broadband connection.
[edit] ROM naming schemes
Most console ROMs will have some information about the ROM in the file name. The following are naming codes that are generally accepted around the Internet. Some of these tags can be used in conjunction with a number to denote that there's more than one version with the same code. Example: There may be two copies of a ROM that were overdumped, so they will be appended with [o1] and [o2] accordingly. This "GoodCodes" naming scheme[1] is usually accredited to the "GoodTools" created by Cowering and is subject to criticism due to its failure to preserve actual information printed on the ROM labels, assigned by the manufacturers. It is a naming scheme designed purely with gamers in mind.
[edit] Hacks and fan translations
Once games have been made available in ROM format, it is possible for users to make modifications to the games. This may take the form of modifying graphics, changing the levels, tweaking the difficulty factor, or even translating the game into a language in which it was not originally made available.
Hacks can often take the form of humorous modifications to games, as is the case with a hack of the NES version of Mario Brothers, entitled “Afro Mario Brothers” which featured the famous brothers wearing Afro haircuts. Also the mod Metroid Redesign is a Super Metroid ROM hack which totally revamps the game and also adds new objectives.
A large scene has developed to translate games. Many games receive a release in one part of the world but not in another. For example, many RPGs which are released in Japan go unreleased in the west. For games where there is an obvious demand in other countries, a group of fan translators will often translate the game themselves. For example, the game Tales of Phantasia (1995) was officially released only in Japan. However, the game's on-screen text was translated into English by the group DeJap Translations in 2001. Further to this, a project called Vocals of Phantasia was setup to go one step further and translate the actual speech from the game. An official English version was not released until March 2006, some five years after the fan translation was released.
see also Fan translation and Rom Hacking
[edit] Legal status of ROMs
ROMs themselves are not illegal per se. This section gives a general discussion of the legal status of ROMs as regards the various uses to which they may be put, though this should not be construed as legal advice.
[edit] Games owned by the user
In some countries, it is legal for an individual to personally make backup copies of a game they own. Individuals may make backup copies for various reasons, perhaps as insurance against losing the game or as redundancy in the event that the original game's medium becomes unreadable. See the section on ROMs and Preservation.
However, in the U.S. it has been illegal since 1983 for a user to create their own backups of video game ROMs. This was decided in the court case of Atari v. JS&A. JS&A manufactured a "game backup" device that allowed users to dump their Atari ROMs onto a blank cartridge. JS&A argued that the archival rule allowed for this. The court disagreed, noting that ROM media was not subject to the same volatility as magnetic media (for which the law was created). Thus, not being so relatively vulnerable, ROMs were not applicable under section 17 USC 117.
Some games companies, such as Nintendo, print warnings inside their game manuals that they do not allow users to make backup or archival copies. Whether or not these warnings in this specific form can be considered valid contracts is legally questionable. For an overview of relevant issues, see user agreement (EULA), shrink wrap contract, clickwrap, Fair Use, Fair Dealing and DMCA.
[edit] 24 hours claim
Some ROM websites claim it is legal to download and keep a ROM of a game one doesn't own for as long as 24 hours, after which it is one's responsibility to delete it. Even though it is widespread (most likely due to copycat reactions), this claim is completely false, as there has never been such a law.
[edit] Officially licensed ROMs
It is, of course, legal to purchase a ROM image which has been licensed to you by the rights holder. For example, Atari made a number of their original arcade games available in ROM format which is compatible with the MAME emulator through the online ROM retailer Star ROMs. Star Roms stopped licensing roms in February 2006, though. Nintendo's next-generation console, the Wii, is backwards compatible with many games for older systems such as the NES, presumably through some (secure) ROM downloading process.
[edit] Freely licensed ROMs
The vast majority of computer & video games from the history of such games are no longer manufactured. As such, the copyright holders of some games have offered free licenses to those games, often on the condition that they be used only for non-commercial purposes. For example, two of the games emulated in MAME, Gridlee and Robby Roto, have been made available under such licenses. As such, they are made freely available from the MAME Home Page.
There are also homebrew ROMs available for many systems. These ROMs are unequivocally legal to distribute and run, per the creator's license.
[edit] Unlicensed ROMs
While some games which no longer make any profit fit into the category above, the vast majority are no longer available in any form. The legality of obtaining such games varies from country to country. Some countries have special exceptions in copyright laws or case law which permit (or discourage less) copying when an item is not available for legal purchase or when the copying is for non-commercial or research purposes, while other countries may make such practices firmly illegal. There is often a distinction drawn between distribution and downloading, with distribution being seen as the greater offence.
[edit] Abandonware
"Abandonware" is a fairly new copyright concept that attempts to bring in the theory of abandonment from trademark law into copyright law. Supporters of abandonware claim that, if a copyright owner no longer offers a particular piece of software to the public, it should be deemed "abandoned" and open to free copying and usage by users. Supporters believe that, while it has no basis in copyright law, it should be considered morally more acceptable to trade in so-called abandonware since copyright holders are, by definition, no longer profiting from the sale of the work in question.
However, the concept of abandonware conflicts directly with the fundamental copyright concept of awarding a copyright creator a finite term during which he/she may enjoy a monopoly on reproduction. Under copyright law, a copyright owner has the right to profit or not profit on their creation. The basis for this right in the United States is the Copyright Clause of the United States Constitution, which empowers the United States Congress:
- To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries
Because abandonware would conflict with the stated goal of granting "exclusive right" (irrespective of profit), it is not recognized in the United States or by signatories of the World Intellectual Property Organization (WIPO) Treaty. Currently, for copyrights to be abandoned, the owner must clearly release the copyright in a writing (which has been done).
In 2003, the United States Supreme Court made copyright law more conservative in deciding Eldred v. Ashcroft, 537 U.S. 186, which affirmed the legality of the Copyright Term Extension Act, an act that extended the current copyright terms by an extra 20 years. The decision noted that, so long as a copyright term is finite, it is permissible under the Constitution. Thus, a copyright in the United States is protected by the full strength of the law until it expires, between 70 and 120 years after initial creation.
[edit] Commercial distribution
Commercial distribution of copyrighted games without the consent of the copyright holder is generally illegal in almost all countries, with those who take part in that activity being liable for both criminal and civil penalties.
Online auction sites such as eBay have sometimes been used by sellers to sell unauthorised copies of games which are advertised as legitimate copies. Such sellers, in addition to violating copyright laws, may also be prosecuted for fraud and/or false advertising.
[edit] Enforcement
There have been few convictions and lawsuits related to ROM trading. Criminal convictions tend to be related to high-profile warez groups which trade combinations of recent films and computer games. In contrast, the ROM scene tends to concentrate mostly on older games. Given the lack of continuing profit from most older games, the grievances of games companies rarely exceed sending a cease and desist order which compels the recipient to stop distributing the copyrighted works in question. Many have argued that it would be irrational for a company to spend money prosecuting for games that they are no longer making profit from, as there would be no damages to speak of. Even so, this has not deterred Nintendo from pursuing a number of lawsuits against ROM distribution websites via non-profit subsidiaries. The reasoning for Nintendo's defense of its aging properties may be explained by its Wii store, which allows users to purchase these games for emulation on the Wii for a significant markup.
[edit] See also
[edit] References
- ^ PHWiki:GoodCodes, accessed December 1, 2006
