Redumper Warnings & Processes

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Latest revision as of 08:36, 13 September 2024

redumper Warnings and Processes

redumper logs can contain a range of warnings of interest to moderators. Some of these will always require further action, while others will help to inform moderators of areas of interest or potential concern.

Warnings requiring further action

"Show stoppers" requiring discard of submission

The following four warnings effectively mean that the drive being used does not support some fundamental feature required for redump purposes. Submissions with these warnings should be discarded and the dumper directed to the List of supported disc drives

1. warning: drive doesn't support reading of subchannel data
2. warning: drive doesn't support C2 Error pointers
3. warning: unsupported drive read method
4. warning: subchannel data is not available, generating TOC index 0 entries

Additional action required to check/process

warning: unable to read CD-TEXT, SCSI ({})

Drive failed to read CD-TEXT, questionable and this shouldn't pop up on compatible drives.

Not sure what the process is here

warning: descramble failed (LBA: {} .. {})

An indication of CD-ROM standard deviation and potential mastering issues, including, but not limited to, disc write offset shift

Not sure what the process is here

warning: TOC / QTOC mismatch

TOC and subchannel desync that might affect track split or CUE-sheet flags and track type, redump.org favors TOC based split.

For Audio CDs, these warnings can be safely ignored.

There may be a requirement for QTOC-based split for certain discs (CD-i, PC Engine?), but the decision has to be made which variant is preferable for a given disc

warning: incomplete dump detected, using available dump size

Dump is incomplete with regard to TOC lead-out entry, safe to ignore for dumps with TOC lead-out entry that spans beyond physical media size, such as unlicensed early [PS2] Datel discs, such discs can be dumped either with --stop-lba=<value> or Ctrl+C redumper interruption and split has to be performed with --iso9660-trim option, this is advanced use and will be covered later

Not sure what the process is here

warning: split is performed by QTOC

Indicates the use of --force-qtoc option which instructs redumper to perform a subchannel based track split

Process

1. If there has been prior agreement with the dumper to submit on the basis described above then
   • Process and add the dump according to usual rules, otherwise;
2. Discuss with the dumper and discard the submission if required

warning: lead-in starts with unavailable sector

For some discs, it is not always possible to capture all of the lead-in data present, resulting in this error.

Process

1. Confirm which drive was used to dump the disc. If this was an ASUS or Plextor 4824 model, request a dump with another Plextor model. If the dumper does not have another drive available then the disc can be added to the database as follows:
   1. If anything other than 0 offset, ask the dumper to redump/split with --force-offset=0
   2. Do not include Track 0 or Universal Hash information
   3. Add a note that lead-in data is present but could not be captured due to use of a 4824 drive, and that a redump with another drive is required
2. If the disc was dumped with any other compatible Plextor, then request the dumper to redump the disc with the commands --force-offset=0 and --plextor-leadin-skip

warning: lead-out ends with unavailable sector

We are usually able to get ~100 sectors of last session leadout with any good Plextor, including 4824. In some circumstances, we will get a submission where the non-zero leadout data exceeds these 100 sectors.

Process

Either:

1. Use RibShark's 3.10 ASUS drive firmware and dump with --overread-leadout option to get more leadout
2. Use a trap disc to get more leadout
3. If either solution above is unrealistic
   • If the offset is already at 0, add to the database as is without Track A/AA and Universal Hash, and with a note in the comments ("Lead-out contains nonzero data but could not be completely read")
   • If the offset is not 0, request the dumper to resplit or redump with --force-offset=0, add to the database without Track A/AA and Universal Hash and with a note in the comments ("Lead-out contains nonzero data but could not be completely read, used redumper option --force-offset=0"). Do not include Universal Hash in this case.

Informational warnings

The following warnings either indicate some useful information about the dump, or can be safely ignored.

warning: fake TOC detected, using default 74min disc size

Indicates invalid TOC entries, the only known disc that generates such a warning is [PSX] Breaker Pro NTSC PAL

warning: incomplete pre-gap (session: ..., unavailable: {}/{})

This is an indication that drive didn't manage to get full 2 seconds of pre-gap, at the time of writing, this is expected (in certain circumstances???) and can be ignored, unless either of the lead-in/out warnings above obtain.

warning: lead-in contains non-zero data (session: {}, sectors: {}/{})

Informational, guarantees that Track 0 will be generated

warning: lead-out contains non-zero data

Informational, guarantees that Track A/AA will be generated

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