As many of you will already know, for some time now our own superg has been developing a new dumping tool by the name of "redumper." This is designed to be a portable, byte-perfect CD dumper which supports a range of advanced functionality while being simple to pick up and use for new users.

Over the course of the past year, while testing redumper, we have identified a range of cases where it solves many long-standing problems with the way certain technical aspects of Audio CD as a format are represented and preserved, and we believe it represents a major step forward for the project.

On that basis, following lengthy discussion among staff, we have decided that as of 01 March 2023 00:00 UTC, redumper will become the only eligible dumping tool for submitting Audio CDs to the Redump project. We have provided a grace period for submission of DIC dumps as we are aware that many dumpers will already be partway through their workflow and in some cases may no longer have access to the physical item, but note that after the above date no DIC dumps of Audio CDs will be accepted.

We appreciate that this represents a major change, and it is not a decision that has been made lightly. We are doing this because we genuinely believe that redumper represents the way forward when it comes to proper preservation of Audio CDs.

**Please note that for the moment this change relates only to Audio CDs - all other formats including Enhanced CDs may continue to use existing dumping methods**


Where do I download redumper?
The latest stable build of redumper can always be found at

How do I use redumper?
For the moment, redumper is command-line only but very simple to use. The most basic command to start off with is:

redumper cd --verbose --retries=20 --image-path=<output_directory> --image-name=<image_filename_prefix>

Some additional values you may want to provide:
--drive=X - point redumper to a specific drive, otherwise it will automatically find and use the first drive with a disc present
--speed=X - specify a dumping speed, otherwise redumper will default to the fastest speed the drive is capable of

A full guide to advanced use of redumper can be found at and at

Any questions you have about redumper can also be asked in the VGPC Discord (, which has a dedicated redumper channel.

What do I need to submit a redumper dump?

As with DIC, you will need to provide the relevant log files so that moderators can check your dump is good. In the case of redumper this consists only of the .log file for most dumps, although occasionally moderators may ask for you to provide other files to check complex cases. As the .log file is relatively small, the contents can either be pasted directly into the "Comments" section of the New Disc form or provided in a separate code block as part of a forum submission. If you do upload the log file to an external filehoster, there is no need to compress it.

Why are we making this change?
The present method of dumping Audio CDs using DIC in some cases leads to imperfect results, including:
* Failure to capture data in the lead-in and lead-out
* Occasional imperfect track splits
* Audio CDs with different write offsets being treated as (Alt) releases
redumper correctly solves these issues in a way which allows extra data to be captured in all situations. For some discs, one true disc write offset can be detected. For the discs where there is data in lead-in/lead-out, such data will be moved out only if it fits into the usual range (e.g. the data spillover is a result if disc write offset). Lastly, if nothing else could be done, the disc will be dumped with offset 0 and lead-in and/or lead-out data will be stored as separate tracks.

redumper can also generate a Universal Hash which can be used to correctly match Audio CDs with different write offsets.

A full technical explanation and discussion can be found at

Does this mean all my old dumps are considered bad?
No, many redumper dumps accurately match those made using DIC and, while redumper does provide some additional information such as unique hash, we are not considering all Audio CD dumps previously done with DIC to be bad.

However, given that there is a small but significant minority of discs which are affected, we would welcome those who have already contributed Audio CD dumps redumping their discs with redumper - the additional information generated can be posted as fixes on the Redump forum.

What about verifications made prior to this change?
Any Audio CD verifications made using DIC prior to the date of this announcement will be processed as usual, and we expect that the vast majority of them will be accepted. There may be a few rare cases where a more accurate redumper dump has been made since the verification was submitted (meaning that the DIC hashes are now known to be incorrect). In these cases we will ask dumpers to submit new logs using redumper.

Does this affect Enhanced CDs?
No, Enhanced CDs offset is detected using a data track and these are not affected by the new dumping method

Should I use redumper for all CDs with audio tracks?
No, for the moment the main use case for redumper for Redump purposes is to correctly dump Audio CDs. In time we expect to expand support to other systems, and if you would like to do a redumper dump in addition to a DIC one, that will be helpful in catching any edge cases where one tool may be doing something incorrect and help both developers to improve their tools.

The moderation team may from time to time ask dumpers to retry a dump with redumper if we have reason to suspect that there are issues with a DIC dump.

Do I still have to use plextor / compatible drives as listed in the wiki?
YES, for now!  While we hope to expand compatible hardware for use in all disc types eventually, for now, this announcement and the acceptance of redumper dumps, does not change in any way the rules for required hardware for dumping CD-ROMs.

Do you know if MPF will add Redumper support in the future?

Lugamo wrote:

Do you know if MPF will add Redumper support in the future?

Yes, it's currently being built.

superg wrote:
Lugamo wrote:

Do you know if MPF will add Redumper support in the future?

Yes, it's currently being built.

Nice, thanks.