Redump.org

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:Most other projects encourage you to backup your discs in such a way that data is lost. Our methods of preservation try to backup every bit of data contained on the disc. In this way your dump should be as close to a 1:1 copy as possible. More information about our methods is covered in the '''Technical''' section below.
:Most other projects encourage you to backup your discs in such a way that data is lost. Our methods of preservation try to backup every bit of data contained on the disc. In this way your dump should be as close to a 1:1 copy as possible. More information about our methods is covered in the '''Technical''' section below.
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'''Why are "verifications" necessary and/or helpful to the project? Isn't one dump good enough?'''
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:Verifications are vital in verifying that the information in the database is accurate, and that a dump is reproduceable by another person using the same tools and methods.  An existing dump could be erroneous due to a variety of factors, including user error, hardware and software issues, and more.  Furthermore, even when someone is doing everything correctly and has adequate software and hardware, there is a chance that their dump could be incorrect, due to the way data sectors on a disc are read and validated (especially Compact Discs). In most cases, the data will be read and verified successfully, but the process of reading data is not infallible, so there are times when a second dump of the same disc could provide differing information.  Verifications help to identify and correct some of these issues.
==Technical Questions==
==Technical Questions==

Latest revision as of 01:19, 8 May 2023

Please read the Redump.org disclaimer.

Contents

Overview

What is Redump.org and what is your goal?

Redump.org is a disc preservation database and internet community dedicated to collecting precise and accurate information about every video game ever released on optical media of any system. The goal is to make blueprints of the data on console and computer game discs. Redump.org also provides guides to ensure the dumps are correctly done. Users of the website who follow the guides correctly are encouraged to share their results to help build the database. Multiple dumps of games with the same serial number by different people are collected to ensure the same results are gathered, which help correct any incorrect dumps in the database as well as to help recognize alternate versions of the same game.

Why is it called Redump?

A "dump" is a slang term, used as a noun, to describe the resulting data obtained in the backup process. The term can also be used as a verb, as in: "I'm going to dump this game." Many groups in the past have attempted to preserve video game data with varying degrees of success. We believe that our methods of preservation are more accurate at preserving all the information contained on a disc than previous attempts made by other groups. The name "Redump" is a way of saying we need to dump again or redump games that have been dumped by others. The name "Redump" can also refer to the way in which our database is setup. A second dump or redump is required to confirm the accuracy of an unverified dump in the database.

Isn't dumping games illegal?

Redump.org does not provide copyrighted material nor do we condone software piracy. Please read the Redump.org disclaimer. You will need to consult your country's laws to confirm whether or not backing up the data on your discs is legal. However, "sharing" copyrighted material is definitely a crime and will not be tolerated here. If you want a game; buy it. Video game developers deserve money for their hard work.

What do you provide on this site?

Our database contains information about copyrighted data such as titles, version numbers and checksums, such as CRC32/MD5/SHA1, but not the actual data contained on the discs. We also provide links to tools and guides to assist you in dumping your discs as personal backups. We don't provide games so please don't ask where to download them. We encourage you to join our community and share information about the backups you create. The Contributing section below will provide you with more information on how to do this.

What's the purpose of this information?

You can use this information in the database so that you can compare a backup you've made to a backup someone else has made of the same disc, even with different PC configurations and drives. This comparison will verify that you've dumped your disc accurately and it's not faulty. The backup you've created can then be archived in case your disc is damaged in the future. We give you information you can use to preserve your games and any information you give us helps others to preserve their games as well. Giving back to Redump.org is covered in more detail in the Contributing section below.

Why preserve game discs?

Nothing lasts forever. Optical media is especially susceptible to damage in the form of scratches, cracks, heat, sunlight, etc. Preserving these discs now will ensure that future generations aren't deprived of our video game history.

What sets Redump.org apart from other projects that have similar goals?

Most other projects encourage you to backup your discs in such a way that data is lost. Our methods of preservation try to backup every bit of data contained on the disc. In this way your dump should be as close to a 1:1 copy as possible. More information about our methods is covered in the Technical section below.

Why are "verifications" necessary and/or helpful to the project? Isn't one dump good enough?

Verifications are vital in verifying that the information in the database is accurate, and that a dump is reproduceable by another person using the same tools and methods. An existing dump could be erroneous due to a variety of factors, including user error, hardware and software issues, and more. Furthermore, even when someone is doing everything correctly and has adequate software and hardware, there is a chance that their dump could be incorrect, due to the way data sectors on a disc are read and validated (especially Compact Discs). In most cases, the data will be read and verified successfully, but the process of reading data is not infallible, so there are times when a second dump of the same disc could provide differing information. Verifications help to identify and correct some of these issues.

Technical Questions

What is optical media?

CDs, DVDs, GDs, NODs, UMDs, Blu-ray discs, etc. If it spins, is read by a laser and has digital game data on it; we want to preserve it.

Why do I need special hardware to dump [x] media for redump?

Discs, particularly CD-ROMs, are somewhat complicated and have data on them that can't be read by just any drive or software, including data that is required for certain games to function properly (e.g. copy protected games). The drives we recommend are capable of reading more information than most standard drives, which helps us to preserve a more complete digital image of the media, for posterity. Additionally, the drives we've listed as compatible, have undergone significant testing by hundreds of contributors, over many years, with tens of thousands of discs, enabling us to provide reliable hashes and in many cases, verified hashes, which fulfills the main purpose of this project.

What is a pressed disc?

"Pressed" discs are stamped out in a plastics-molding stamper. The data patterns, represented as a series of pits and lands, is permanently molded into the plastic during the stamping process. Basically, its the same process that was used to make vinyl records (and CD's, for that matter), just ramped up a few orders of magnitude in precision. After the plastic has been stamped, it then gets coated (via vacuum deposition) with a few-atoms-thick layer of reflective metal, and another layer of plastic is bonded onto the top. During playback, the laser's reflection angle is subtly altered depending on whether there's a pit or a land in front of the beam, which causes the reflection to hit or miss the detector. These hits and misses become a binary data pattern.

Why you split the tracks?

wip

What is offset and why is it important?

wip

Why dump at 2352 bytes per sector and not 2048 bytes?

wip

Why don't you dump subchannels?

wip

Is it true that some data on a disc can't be accurately copied?

As of this moment, yes, that is true for some types of optical media. The subchannel data of a compact disc is especially difficult to retrieve with perfect accuracy. Certain copy protections can prove difficult to backup as well, but we are working on these issues.

Contributing Questions

I want to contribute, but where do I start?

Thank you for your enthusiasm and desire to help us preserve our video game heritage. Where you start depends on what you'd like to do. There are more ways to contribute than just what is written here, but the following should give you some ideas. You can post answers to questions in the forum or IRC channel. You can add or modify information in the wiki. You can program useful tools to assist the community. You can dump optical media and submit the information about those dumps to our database. However, contributing to the database requires more reading and preparation. Please see the Forum and Dumping Guides for how to contribute in this way.

What discs are accepted?

Pressed optical media discs that contain video game data or video game related materials or multimedia, are accepted into the Redump database:
  • All console and computer-based video games.
  • All video game Demos, Betas, Unlicensed, Promos and Press discs.
  • Bonus discs in Limited/Collector's editions, and Bundled discs (discs bundled with video games, magazines, etc.):
    • Standard movies are not accepted, but if the bundled movie is based on an IP that's predominantly video game based, it may be accepted. Non-movie content is generally acceptable but mod discretion will be used in any case deemed too out of scope for the project.
  • Additionally, other optical media discs for certain video game or multimedia systems no longer in production (such as CD-i and FM Towns), are also accepted into the Redump database.

For the following systems we only accept video games and video game related content:

  • IBM PC Compatible
  • Mac Compatible
  • Audio CDs
  • DVD-Video
  • BD-Video
  • HD DVD-Video
  • Video CDs (non CD-i)
  • Universal Media Discs (UMDs)
Burned recordable discs (CD-Rs, DVD-Rs, etc) are accepted as well when they contain prerelease content or if they were released in this form by their publisher. These still must be video game related in their content.
If you have any questions about whether your disc is eligible, please post your question in the forum.

What do you mean by "video game related?"

This is difficult to define exactly. The core content of the item should be coverage of, material for, samples of video games, etc. Here are some good examples of directly video game related content:
  • (PC) Press Kit discs for video games, demos, promotional materials on discs, etc.
  • (DVD-Video) Promotional DVDs highlighting demos, trailers or gameplay for video games. DVD-Video Interactive games (dedicated games which can be played using only DVD-Video hardware).
  • (Audio CD) Video game soundtracks, compilations, etc.

Please note: movies and tv shows based on video games, drawing inspiration from them, or with video game "themes" are not eligible for redump. This includes but is not limited to movies like Pixels, Mario and Zelda cartoons, etc.

If you have a question about whether your item is eligible, please consult the forum.

Should I dump discs containing a computer application?

Maybe. It depends on the usage of the application. Is the application used in such a way that it relates to a certain game or a type of video games? For example, a level editor application for the game "Doom" on a disc could be added to the database. However, a disc containing programming tools like "Visual C++" would not be acceptable for the database. While both the level editor and the programming tools can both be used to create or modify game data, the programming tools are not specifically designed for that purpose. If you are unsure of the difference or think a particular disc should be an exception, please consult the forum.

Should I dump bootleg discs?

Maybe. It depends what you mean by "bootleg." The information added to the database should be from pressed optical media and not a disc that was burned in a computer. If you are unsure of the difference or think a particular disc should be an exception, please consult the forum.

Should I dump operating system discs?

Generally, no. We are not accepting information about operating system discs unless the disc is used in a system no longer in production, such as as FMT, PC-98, or X68000. For example: http://redump.org/disc/15004/ and http://redump.org/disc/12542/. See the above item about what discs are accepted for more detail. Operating system discs for IBM-PC / MAC, are specifically not accepted.

Should I dump ___ discs?

If you can't find the answer here for a particular type of disc, please consult the forum.

How do I know if my disc is already in the database?

If you have already dumped your disc:
  • The best way to find out if your disc is in the database, is to use the "Quick search" feature, which is in the upper-right portion of redump.org. Enter the MD5 or SHA-1 hash information in your search, and if the disc is in the database, it will populate that page.
If you have not yet dumped your disc:
  • You can check the missing lists on our wiki to see if your disc is listed. However, since the missing lists aren't always 100% up-to-date, we recommend always searching for your disc using the "Quick search" feature on redump.org. You can search by Title, Foreign title, or Disc Serial to see if the disc is listed. Please note: even if you get a result, it is always worth dumping your specific disc to see if it matches any or is a revision / new disc.

Contact

Forum

The forum is the heart of this community. Browsing the various sections and reading some of the posts will give you an idea of how this site works. The most up to date news, discussions, guides and dumps can be found on the forum. It can also be a great source for answers to questions not found in the Redump.org wiki.

How do I reply to a topic or create a new topic in the forum?

The first step is to register for a user name at the Redump.org forum. After you've completed the registration process you can login with the user name you've chosen. To reply to an existing topic, click the name of the topic in which you want to make your reply. Then click the "Post reply" link in the upper right corner. Type your message and click the "Submit reply" button. To create a new topic, click the name of a section in the forum in which you'd like your post to appear. Then click the "Post new topic" link in the upper right corner. Type your message and click the "Submit topic" button. The "Post reply" and "Post new topic" links will only appear when you've registered and logged in with your Redump.org user name.

How do I search the forum?

Before asking a question please make sure it hasn't been asked before. Use search located on the top of the page. Be sure to also read the stickies in each forum section.

IRC channel

More questions? Join the IRC channel.

Thanks

We are thankful to all people which helped build up this database that's always growing, gave us feedback, spread the word around, fixed errors, or in any way contributed to this ongoing project!

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