Audio CD Moderation Guide

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Latest revision as of 08:13, 10 October 2024

General Audio CD notes

Description: "Audio CD" refers to the red book format of CD-ROMs to distribute music and other audio. This also includes the mixed format "Enhanced CD."

When deciding on titles for Audio CDs, the default assumption is that variants of the term "Soundtrack" (Original/Official/Game/Collector's Edition/etc. Soundtrack) should be added as a subtitle and separated from the main item title with a colon. So, "Example Game: Official Soundtrack" for example. There may be case by case exceptions to this rule. For example where the term is presented as part of the main title on the item itself, with no clear stylistic distinctions or line breaks etc. to separate it. See the example below, which would be properly rendered as "Fighting Vipers Original Soundtrack" for an example of this kind of case

Fighting Vipers Original Soundtrack

Languages do not get added unless the content is like an audiobook in nature (narration, drama CD) -- Needs discussion, community is not a fan of this.

Serial field is for serials present on the label of the disc, all other serials should be put in comments.

Track times taken from VGMDB may be incorrect, recommend taking times from foobar2000 or other tools, or leaving times blank entirely.

Ideally, the contents should be listed exactly as on the item, for accuracy. This isn't always done of course. If you've confirmed it was done, please add the following line to the comments verbatim:

Track layout, capitalization and spelling are as they appear on the item.

Universal Hash provided by redumper log should always be included in comments. Example: PixelJunk Monsters 2.

When redumper is unable to detect any other write offset for an Audio CD, it will use a fallback offset of 0 - this can be safely added as the offset value. For any entries made before redumper and discimagecreator supported detected CD Audio write offset, leave offset empty unless otherwise specified (do not set "0" as the value).

New Audio Disc Submissions

IMPORTANT:

Now that we are requiring Redumper to be used for new audio discs, there are some important differences we need to be aware of when processing new disc submissions:

• Please check for existing discs in the database, that have the same title, but different track hashes.
• If a Track 0/00 is generated and the dumper used a build PRIOR to redumper build 117, please ensure the dumper has dumped the disc twice. Due to a known Plextor firmware bug there is a possibility that the first attempt will return garbage data.
• Plextor 4824 model doesn't support reading lead-in, Plextor model 4012 gets very little amount of lead-in sectors. If dumper is using these two drive models and (Track 0/00) was generated, it might be incomplete. Although this is a rare situation, it's adviced to pay attention to redumper warnings as explained in Redumper. If such lead-in warnings exist, the disc should be redumped on another drive. Please review submissions for this.
• If the Universal Hash matches between the existing disc, and the new disc, that means the new disc you are processing should be added as a verification with a different offset.
• Some discs will have a genuine offset of 0 - to differentiate these from cases where a fallback 0 offset is applied, add the comment 'Ring #X Perfect Audio Offset: +0'
• redumper's refine functionality allows dumpers to "stitch" dumps from multiple copies of the same disc in order to fully refine errors and generate one good dump e.g. where the two copies used have errors in different areas of the disc. Such dumps *may* be accepted if we are confident that all other proper procedures have been followed, but should be added as blue regardless of how many discs were dumped to generate the final result

If you are unsure about how to handle a particular warning, please check redumper Warnings & Processes for more information.

Note: 'Universal Hash' and 'Ring non-zero start' should NOT be added for Enhanced CDs (or any type of Audio CD which has a data track).

Checking redumper submissions against the database

Note that because of the way redumper correctly handles offsets for audio CDs, there is a possibility that dumpers will submit what appears to be a new dump - one with track hashes which do not match the database - which is in fact a verification of an existing entry in the database, but with a slightly different offset/non-zero data start. There are some easy steps you can take to check for this scenario.

1. Search for discs which closely match the title of the new dump (e.g. "SaGa Frontier: Original Sound Track (Disc 2)") and see if any of the core details match up (mastering code, mastering SID, etc.)
2. If the disc has already had a redumper dump submitted, it will have a universal hash - check if this matches the submitted dump. A Universal Hash already noted in comments can be found by searching for the value minus the final character (i.e. if the hash is e7af93523dcf254b9e62496c924ca3f50e943f8e, use the following search string http://redump.org/discs/quicksearch/e7af93523dcf254b9e62496c924ca3f50e943f8/comments/only). Searching using the complete hash value will NOT work
   1. In most circumstances, a matching Universal Hash means that the disc is a verification and should be processed as such. However, before processing you should check that the disc size, track sizes and track splits match between the two discs. It is possible for two distinct releases to share the same data but to split the tracks in different ways - for Redump purposes we treat these as two separate entries. See http://redump.org/disc/97695/ and http://redump.org/disc/99553/ for a practical example of this
   2. If the disc is a true verification, pay close attention to the non-zero data start as it is possible that this will differ - see notes above under "New Audio Disc Submissions" on how to address this
3. If the disc has only been dumped with DiscImageCreator previously, and you strongly suspect that the redumper dump is a verification, ask the dumper to resplit using a forced offset of 0: redumper split --force-offset=0. You can then check these track hashes against the database to see if they match. If all hashes match, then this is a verification as well and it should be processed as such

In scenario 3 above, note that the previous DIC track hashes should be replaced with the hashes of the redumper dump which correctly identified an offset. If scenario 2 applies, refer to the guidance above regarding Universal Hash and discs with different non-zero data starts.

Matching Universal Hash / different cuesheet

Occasionally, it is possible to encounter discs which have matching universal hashes but differing track hashes purely due to cuesheet differences (see http://redump.org/disc/105344/ and http://redump.org/disc/112883/ for an example).

In this case, the entries should be kept separate and an appropriate datfile version applied (generally Alt), along with a note in comments in both entries stating "Universal Hash match with [matching entry] but differing track hashes due to cuesheet differences"

Merging entries which have the same Universal Hash

As legacy audio CD submissions are redumped using redumper, it is likely that we will encounter situations where previously separate entries (reprints, variants, etc.) are found to in fact have the same Universal Hash and to be offset variants of one another. In that case, these should all be merged into a single entry, with all ringcodes and offsets transferred and updated.

In this case, the following rules apply:

• If multiple variants of a CD are found to have identical universal hashes, the earliest entry in the database should be used as the reference entry into which others are merged
• UNLESS a case occurs where a particular variant has a true 0 offset, in which case this should become the reference entry
• Here is an example of an entry with multiple discs merged: Chrono Cross: Music Selection
• The first entry has a Write offset of 0, and the comment 'Ring #1 non-zero start: +42352' [from redumper log]. The second disc pulled the same Universal Hash, with the non-zero start as +42246, which is 106 'less' than the first entry. Therefore, the second ring is added with the offset -106. You can find the non-zero start value in the redumper log file from this string: "non-zero data sample range: [ +14917 .. +157387599]", in this case the non-zero start is +14917.
• PLEASE pay attention to the comments, as they may need to be adjusted over time, identifying which Ring # is being referred to. For example, if it so happens that you add a disc and the ordering of the Rings changes, we should update the comments to reflect the non-zero starts that apply to those specific Rings as listed in the redump entry.

Where possible, explanatory notes should be added to show which version/variant of a CD each ringcode and offset refers to - see http://redump.org/disc/94630/ for a good example of this

Other warnings and issues

Large offset / default split causes audible cutoff

In a few very rare cases where an Audio CD has a large offset, the default split may result in audio data being moved out of Track 01 and into a separate Track 00 file. Due to the way redump currently handles (or doesn't) lead-in/lead-out data, this may result in the dump having an audible cutoff at the start.

In these cases, and only through careful consultation between staff and the dumper to investigate all other potential methods of handling the problem, it may be acceptable to add the dump using a forced offset of 0.

If this is done, a note should be added as follows: Used redumper option --force-offset=0 as default split audibly cuts off Track 01

Large offset / default split causes audibly incorrect track boundaries

Similar to the above, in some cases where a disc has an offset that is out of spec (greater than +21065), redumper's default split / movement of data into Track 00 may result in audibly incorrect track boundaries (start of track X heard at end of track X-1).

In this case a similar process to the above can be followed, and a noted added as follows: Used redumper option --force-offset=0 as default split results in audibly incorrect track boundaries

Enhanced CDs

Please note! (03-26-23): Currently, Universal Hash is not implemented well for multisession / enhanced CDs. If Universal Hash exists in a submission or entry, please remove it until this feature is fully implemented.

Enhanced CDs may have languages added

Multisession Enhanced CDs have a gap of 11400 sectors between sessions

How to calculate multisession range (MPF should do this automatically now):

• Open disc.txt in logs and go to TOC
• Session 1 range is LBA 0 to (last sector in session 1 minus 11400)
• Session 2 range is (first sector in session 2 to last sector of disc)

Example:

Audio Track  1, LBA        0 -    14887, Length    14888
Audio Track  2, LBA    14888 -    15484, Length      597
Audio Track  3, LBA    15485 -   226234, Length   210750
Audio Track  4, LBA   226235 -   226831, Length      597
Audio Track  5, LBA   226832 -   227278, Length      447
---
Session 1: 0-3487 -> (14887-11400)
Session 2: 14888-227278

Editions / Datfile versions

Where an audio CD is bundled as a bonus disc with a game, the edition and datfile version should always be set to "X Game Bundle".

If the disc is bundled with a release of the game for more than one system (see e.g. http://redump.org/disc/81769/), then the Edition field should represent each individual system (PS3 Game Bundle, PS4 Game Bundle), while the Datfile Version field should use the single term "Multisystem Game Bundle"

Please note that where an audio CD is bundled as a bonus disc with a book or magazine, the edition may be set as "Book Bundle" / "Magazine Bundle", but the datfile version should be left blank.

Pre-Order Bonus discs, First-Print Bonus discs, and other similar types of discs/editions that are not always bundled, do not get a datfile modifier. Additionally, if multiple editions of a disc exist, but not ALL of them are bundles, there is no datfile modifier. For example, if a disc has an Original release and a PC Game Bundle release, there is no datfile modifier unless one is required due to a collision.

The following standardised terms are used:

• 3DO Game Bundle (3DO)
• 3DS Game Bundle (3DS)
• CD-i Game Bundle (CD-i)
• DC Game Bundle (Dreamcast)
• FMT Game Bundle (FM Towns)
• GB Game Bundle (Game Boy)
• MCD Game Bundle (Mega CD / Sega CD)
• Multisystem Game Bundle (same disc verified as being bundled with the game for multiple systems)
• N64 Game Bundle (Nintendo 64)
• NDS Game Bundle (Nintendo DS)
• NSW Game Bundle (Nintendo Switch)
• PC Game Bundle (PC)
• PC-88 Game Bundle (PC-88)
• PC-98 Game Bundle (PC-98)
• PCE Game Bundle (PC Engine)
• PS2 Game Bundle (PlayStation 2)
• PS3 Game Bundle (PlayStation 3)
• PS4 Game Bundle (PlayStation 4)
• PS5 Game Bundle (PlayStation 5)
• PSP Game Bundle (PlayStation Portable)
• PSV Game Bundle (PlayStation Vita)
• PSX Game Bundle (PlayStation)
• QIS Game Bundle (Bandai Playdia Quick Interactive System)
• SFC Game Bundle (Super Famicom / SNES)
• SMD Game Bundle (Genesis / Mega Drive)
• SS Game Bundle (Saturn)
• Wii Game Bundle (Wii)
• Wii U Game Bundle (Wii U)
• Xbox Game Bundle (Xbox)
• Xbox 360 Game Bundle (Xbox 360)
• Xbox One Game Bundle (Xbox One)