How is AccurateRipDiscID calculated?

[Porcus]

Appears to me as the first three digits are the total number of audio tracks (why three?), last one or two is track number, second-to-last section is CDDB ID -- and actually correct CDDB ID, in contrast to the calculated for the [cddb_id] tag by dBpoweramp, right?

What are the rest? Only derived from TOC, or from the CRCs too?

Reason for asking: I have ripped a few thousand CDs, including a few duplicates and a few same-but-different-pressing -- but there are also a few almost-equals I would like to keep track of (like, a few hundred promos I haven't heard, some of which probably have this annoying voiceover).

[Spoon]

Re: How is AccurateRipDiscID calculated?

[cddb_id] is working correctly in R13.1 (current beta).

Disc ID is from the TOC entirely and nothing to do with CRCs of tracks (the other two are the track start addresses hashed in different ways).

[Porcus]

Re: How is AccurateRipDiscID calculated?

[cddb_id] is working correctly in R13.1 (current beta).

Disc ID is from the TOC entirely and nothing to do with CRCs of tracks (the other two are the track start addresses hashed in different ways).

Does it include information like fractions-of-seconds? The reason why I ask is that there are indeed a few duplicate TOCs when only integer second counts are considered.

And, since the cddb_id tag has been corrected and thus have been changed: has the AccurateRipDiscID tag been consistently calculated since ... the first R13 beta?

[Spoon]

Re: How is AccurateRipDiscID calculated?

It is frame based, rather than second based (1/74 of a second).

[Porcus]

Re: How is AccurateRipDiscID calculated?

Are both cddb_id and AccurateRipDiscID frames-based? (For the former, is there a definite standard on how to calculate?)

Will dBpoweramp's calculated [cddb_id] -- in its presumably correct 13.1 implementation -- always be that eight-char substring of the AccurateRipDiscID, even for "Playstation" type CDs and DbDs?

(I scanned AccurateRipDiscIDs of a few thousand CDs, and whenever the third 8-char block matched, so did the first two. Collisions appear scarcer than I feared.)

[Spoon]

Re: How is AccurateRipDiscID calculated?

Yes the IDs are always the same length no matter what the CD.

The AR disc ID is 3x the size of other IDs.

[Porcus]

Re: How is AccurateRipDiscID calculated?

I didn't ask about same "length", but same "value". The AccurateRipDiscID contains a track number and some ABCDEFGH-IJKLMNOP-QRSTUVWX. My question is, basically:

Will [cddb_id] -- as calculated by dBpoweramp -- always be QRSTUVWX?


Sorry for nagging details ...

[Spoon]

Re: How is AccurateRipDiscID calculated?

Yes I think so.