Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: AccurateRip understanding (Read 24377 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

AccurateRip understanding

I'm going through many posts and doing some tests in order to understand AccurateRip and how it works.
This is what I think I figured so far, so I would like someone to confirm my guesses:

1. Every time someone rips tracks and submits data to AccurateRip it stores results (including CD Id) into rawdata database.
When two or more results for individual track match, the data is moved into "confirmed" database (I don't know what should be name for it). Rawdata database is considered to contain mostly incorrect rip results i.e. rubbish.

When you get in a report:
Accurately Ripped (confidence 33)
That means that 33 other users ripped the same track from the same CD with the same result. Confidence of 3 or more is enough to consider having accurate rip.

Now, if there are 2 pressings of a same CD (same CD Id) and we call them CD A and CD B, although they both have the same CD title and Disc ID, e.g. Forever Blue by Chris Isaac Disc ID: 00127910-9b095e0d. Records in AccurateRip database are stored for each track individually. If we have 5 users ripping e.g. track 3 on CD A (and getting the same CRC A) and another 7 ripping track 3 on CD B (getting the same CRC B), there will be 1 record in "confirmed" database for track 3 with CRC A and another record in the same database with CRC B.

Now if new user rips correctly the track from CD A, he will get result Accurately Ripped (confidence 5)
If new user rips correctly the track from CD B, he will get result Accurately Ripped (confidence 7)

If new user rips from another pressing (e.g. CD C), what he'll get?
I suppose it will be **Rip not accurate** (confidence 7)

If new user rips and has an error in process, I suppose he'll get the same result
**Rip not accurate** (confidence 7).

Can someone confirm.

2. Currently, it's not possible to produce log file from AccurateRip. The only way is to manually do Copy-Paste from AccurateRip report window.

AccurateRip understanding

Reply #1 –
1 Correct
2 Depends on program used.

AccurateRip understanding

Reply #2 –
...and a confidence of *one* is all that is needed to consider your rip as being accurate, assuming of course you aren't comparing to your own submission.

Quote from: greynol on
Quote from: spoon on
If AccurateRip verifies your rip with a confidence of 2 or above then it is error free.
Why not with a confidence of just 1?
Quote from: spoon on
There is a chance that the guy submitted his result previously so the result is his

AccurateRip understanding

Reply #3 –
Quote from: greynol on
...and a confidence of *one* is all that is needed to consider your rip as being accurate, assuming of course you aren't comparing to your own submission.

Quote from: greynol on
Quote from: spoon on
If AccurateRip verifies your rip with a confidence of 2 or above then it is error free.
Why not with a confidence of just 1?
Quote from: spoon on
There is a chance that the guy submitted his result previously so the result is his



But, I think I read somewhere that AccurateRip also sends some kind of machine ID.
Why's that?
I thought it's for the purpose of preventing comparing to user's own submission.


Quote from: spoon on
1 Correct


BTW, what's the real name of "confirmed" database 

AccurateRip understanding

Reply #5 –
>But, I think I read somewhere that AccurateRip also sends some kind >of machine ID.
>Why's that?

So results from one machine can be tracked, but these ids do not make it to the final database. The ids are in the database so when a submission is made, if the drive offset is obviously wrong the results are not added to the database, the user is put on a 'no add list' and previous submissions are purged. It is possible to get a wrong offset (for a drive with no submissions, keying off a different pressing using 3 cds from a compliation), but quite rare.

>BTW, what's the real name of "confirmed" database

AccurateRip, the submissions are just that a jumble of numbers.

AccurateRip understanding

Reply #6 –
Quote from: Nik on
2. Currently, it's not possible to produce log file from AccurateRip. The only way is to manually do Copy-Paste from AccurateRip report window.


dbpoweramp's CD ripper will add AccurateRip Results to both the tags of the ripped songs (as well as accuraterip DiscID) and write the results to the log file.

AccurateRip understanding

Reply #7 –
Quote from: Eli on
Quote from: Nik on


2. Currently, it's not possible to produce log file from AccurateRip. The only way is to manually do Copy-Paste from AccurateRip report window.


dbpoweramp's CD ripper will add AccurateRip Results to both the tags of the ripped songs (as well as accuraterip DiscID) and write the results to the log file.


I thought that DiscID is not generated by AccurateRip but that's an ID that's issued by manufacturer.

AccurateRip understanding

Reply #8 –
Quote from: Nik on
Quote from: Eli on

Quote from: Nik on


2. Currently, it's not possible to produce log file from AccurateRip. The only way is to manually do Copy-Paste from AccurateRip report window.


dbpoweramp's CD ripper will add AccurateRip Results to both the tags of the ripped songs (as well as accuraterip DiscID) and write the results to the log file.


I thought that DiscID is not generated by AccurateRip but that's an ID that's issued by manufacturer.



No, the DiscID is generated by AccurateRip, at least thats my understanding. I'm not sure of the algorithm.

AccurateRip understanding

Reply #9 –
AccurateRip has its own DiscID, it was designed to avoid collisions (unlike cdddb's DiscID)

AccurateRip understanding

Reply #10 –
Quote from: spoon on
AccurateRip has its own DiscID, it was designed to avoid collisions (unlike cdddb's DiscID)

But I believe that two pressings of the same CD title have same manufacturer disc ID.
I call manufacturer disc ID the one printed on the inner ring of a CD, and it seems that those IDs have various formats. I don't know the algorithm how they protect themselves from generating duplicates, but there must be some logic in it.
Do they also have a single AccurateRip disc ID, or each pressing gets different disc ID by AccurateRip, once AccurateRip figures out that they are different pressings.

AccurateRip understanding

Reply #11 –
Different pressings are all identical except the audio is shifted a few bytes, so the IDs are the same.

AccurateRip understanding

Reply #12 –
Quote from: spoon on
Different pressings are all identical except the audio is shifted a few bytes, so the IDs are the same.

... so manufacturers IDs and AccurateRip IDs have relationship 1:1.
There must be some reason why manufacturer's IDs are not used, but the new ones are implemented.
For some performance or similar reason I presume.
Thanks Spoon for your help on this topic.

AccurateRip understanding

Reply #13 –
Quote from: Eli on
Quote from: Nik on


2. Currently, it's not possible to produce log file from AccurateRip. The only way is to manually do Copy-Paste from AccurateRip report window.


dbpoweramp's CD ripper will add AccurateRip Results to both the tags of the ripped songs (as well as accuraterip DiscID) and write the results to the log file.


Is it possible to produce log files using EAC instead?

AccurateRip understanding

Reply #14 –
Quote from: Nik on
... so manufacturers IDs and AccurateRip IDs have relationship 1:1.
No, they don't.  Pressings that differ by only an offset will have the same ID in spoon's database but can have a different id on the inner ring of the disc itself.

Quote from: Nik on
Is it possible to produce log files using EAC instead?
Maybe with a third-party program, otherwise no.

AccurateRip understanding

Reply #15 –
Quote from: greynol on
Quote from: Nik on
... so manufacturers IDs and AccurateRip IDs have relationship 1:1.
No, they don't.  Pressings that differ by only an offset will have the same ID in spoon's database but can have a different id on the inner ring of the disc itself.

 
Got it finally!
Each pressing has different manufacturer's Disc ID in the inner ring, but AccurateRip detects them and gives them the same AccurateRip ID.
Now it all has sense.

AccurateRip understanding

Reply #16 –
One more question 
This is what I've got from AccurateRip for CD that seems to be of a different pressing then the one in it's database:

1. I asume that Disc ID is AccurateRip's DiscID we talked about and there's no easy way to connect it to manufacturer's ID's.
If this report I store and it gets displaced, it's difficult to figure out to which CD it belongs.
2. The first column after (confidence n) is CRC checksum calculated for each track for that CD and the second column is CRC checksum for the track for that CD (but different pressing) stored in AccurateRip's database.

AccurateRip understanding

Reply #17 –
My understanding is this screenshot just means you have a different pressing.

You want it to say Rip Not Accurate for ALL tracks. If it is accurate for some, but not others, then I would be concerned. It could mean something is not working with the ripper, or that the AccurateRip database contains some bad data for that particular CD.

AccurateRip understanding

Reply #18 –
Quote from: ShowsOn on
My understanding is this screenshot just means you have a different pressing.

You want it to say Rip Not Accurate for ALL tracks. If it is accurate for some, but not others, then I would be concerned. It could mean something is not working with the ripper, or that the AccurateRip database contains some bad data for that particular CD.


I agree.
I just wanted some expert to confirm my statements 1. and 2.    because I'm not 100% sure.

AccurateRip understanding

Reply #19 –
If I find that I have a different pressing of a CD, which doesn't exist in AccurateRip database, can I rip such CD in two different PCs with two different drives and compare AccurateRip CRCs.
If they match, can I consider those rips to be correct.
I asume, in that case, when results are submitted to AccurateRip, it will verify that they are coming from two different sources and they are matching, and will include them in its database.

AccurateRip understanding

Reply #20 –
If the CD has a flaw, and if both drives read the same incorrect data, then Accuraterip will tell you that they match. Of course, anyone else who rips the same pressing will be told that that track is inaccurate.

The real strength of Accuraterip is that it will compare different drives AND different copies of the CD.

AccurateRip understanding

Reply #22 –
Quote from: greynol on
Once you compare two different copies of a disc and get matching results, what drives are involved quickly becomes irrelevant.


Of course.
What I ment is that this way I can eliminate drive errors. But still there might be a disc error, because there is nothing to compare it to.

AccurateRip understanding

Reply #24 –
Quote from: greynol on
But getting the same result from the same disc using two different drives is still not a guarantee that your rip was accurate.


Anf that's where Accuraterip comes in, but only if someone else has already ripped the same pressing of that CD.