Accurip detects Corrupted Files, but they play Fine...

[kd4cht]

I am using PerfectTUNES on macOS 10.15.4. I used the Accurip feature and it found 24 FLAC files that are stored on my NAS as corrupt. I tried play a few of these files in VLC and the 3 that I tried play just fine. I tried the same files in AudioStation on my Synology NAS and they played fine there as well. What could cause this?

[schmidj]

Re: Accurip detects Corrupted Files, but they play Fine...

Inaccurate may not mean "corrupt". The files might have been modified by one of the DSP processes. Did you trim silence from the beginning and or end of rips? That makes the checksum different, therefore it will report it as inaccurate. You presumably wanted to remove the silence, so it sounds fine, just without the silence you didn't want to hear. But it no longer matches the unmodified checksum, it is "inaccurate". Applying volume adjustment (not just tagging the track with a playback volume adjustment, but actually "applying" it also changes the checksum.

Beyond that, you could have tracks with a few bad frames. They will show up as inaccurate. One frame is 1/75th of a second. And only a few bits of the frame might be bad. You are unlikely to hear such an error. You should use the results of the Perfectunes accuraterip list to tell you which tracks you might want to listen to, so you can decide which ones to ditch (because they are bad enough that you don't want to listen to them) and which ones have no audible impairment or the impairment is slight enough that you don't mind hearing it. There are plenty of things I hear in recordings that could be a human error in performance or production (or an effect the producer wanted) or they could be a reproduction error.

Most of us of any age listened to records with pops, clicks, hiss, even skips and just accepted that as part of listening. Now people obsess over finding two bad bits out of the entire performance. "Oh, it's not bit perfect" They need to get over it.

This doesn't mean that the Accuraterip process isn't worthwhile, either when ripping or after the fact to check your files, I'd certainly like to know if a track starts to skip in the middle when I'm ripping it while I can try cleaning it, or ripping in a different drive, or wow, buying another copy on EBay, or even borrowing it from the library to rip their copy. And if all else fails, I can simply erase the file if it is bad enough I don't want to hear it again. And I'd like to know if suddenly several tracks on my hard drive won't play because of data errors (You do keep a backup, don't you?)

So, yes, 24 tracks out of how many? Were they ever "bit perfect"? If they sound OK, just keep a note of which ones, so when you check them again, you'll know those were already not "bit perfect". If they are bad enough, you have to figure out whether to replace them or ditch them.

And yes, there can be files that are "corrupt" Many won't play at all, but there can be corruption that messes up the metadata, not the audio, so the accuraterip check can't determine what the file is, and can't look it up in the database, yet the actual audio plays "bit perfect"

[kd4cht]

Re: Accurip detects Corrupted Files, but they play Fine...

That makes sense. I seem to recall that the few I have checked so far dBpoweramp had to re-rip some frames. So, that may be the issue.

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

This is of recent interest to me. I've been trying to clean up my collection with the help of PerfectTUNES. My collection is in good shape but there are exceptions. I've even gone as far as buying downloads of some corrupted songs from Quboz. In general, this solves the corruption problem. However, on a couple, even the new downloads show as corrupted. This seems unlikely. I've experiment with a couple scans: keep the download unedited (metadata and album art), edit the download by changing the filename (to match the naming standard of the other songs in the album) and editing the metadata and adding album art. The unedited song scans without error; however, the edited song file scans with a corruption error. Again, only changing the file name (not extension) and editing the metadata. It's not a huge issue but does make me wonder what's going on.

[Spoon]

Re: Accurip detects Corrupted Files, but they play Fine...

How are you editing the metadata? What are the files? FLAC?

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

Using dbpoweramp to edit the metadata (access through the windows shell). All the files are FLAC. Oh ya, I have cleared the cache and not in PerfectTUNES. Makes no difference. Also tried deleting the txt file that exists in the album folder from the original dbpoweramp CD rip.

[Spoon]

Re: Accurip detects Corrupted Files, but they play Fine...

One of the 'corrupted files' it is reported as corrupted how? a miss match with AccurateRip (in accurate), or the file is reported as broken (corrupted)?

If the latter, try right clicking on the FLAC file >> Convert To >>

choose the encoder as 'Test Conversion' are any errors shown?

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

The specific error in the report log is Track InAccurate. I tried encoding using Test Encoder and don&*8217;t get any error: no result is reported. I&*8217;m not sure what&*8217;s supposed to or might happen with this encoder selected. I also tried in on a track I know for sure is inaccurate and get no result either.

[Spoon]

Re: Accurip detects Corrupted Files, but they play Fine...

What metadata changes are you making?

[garym]

Re: Accurip detects Corrupted Files, but they play Fine...

not clear if this was ever answered, but if you are simply getting "inaccurate" messages, this is not a corrupt file. Inaccurate simply means that the file does not match the information in the AccurateRip database. There could be lots of reasons for that. You have a different CD pressing, etc.

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

What metadata changes are you making?

In the case of both files that show inaccurate, I changed album titles from The Chemical Brothers to Chemical Brothers, The and The Crusaders to Crusaders, The. Also, I changed the Genre tags to match my system. That’s it.

[Spoon]

Re: Accurip detects Corrupted Files, but they play Fine...

That is because the album name is used to look up the disc in AccurateRip (at least to group the files together)

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

Interesting. So, if I changed all the other files to The Chemical Brothers, only the new, downloaded, one would test accurate?

[Spoon]

Re: Accurip detects Corrupted Files, but they play Fine...

You cannot have 2 tracks the same, so if replacing with a downloaded one:

move the ripped track somewhere PerfectTUNES is not looking
change the metadata (album and album artist) to match the orginal.

[Dale Johnson]

Re: Accurip detects Corrupted Files, but they play Fine...

Sorry to belabor this, I don't have 2 tracks the same. I replaced the original, inaccurate track, with the downloaded track, then changed the metadata of the downloaded track to match the remaining ripped tracks. I deleted the original, inaccurate, ripped track.