FLAC Conversion Error

[bjast]

I'm getting the following conversion error when converting a 24/96 FLAC file to either 16/44 AIFF or 24/96 AIFF:

"Error converting to Aiff, 'Z:\Audio Downloaded\eClassical Downloads\October 18, 2012\Bach, J.S. - Early Cantatas, Vol. 3 - Bwv 21, 172... - 109 - Himmelskonig, sei willkommen, BWV 182 - Himmelskonig, sei willkommen Chorus.flac' to 'Z:\Audio Downloaded\eClassical Downloads\October 18, 2012\Bach, J.S. - Early Cantatas, Vol. 3 - Bwv 21, 172... - 109 - Himmelskonig, sei willkommen, BWV 182 - Himmelskonig, sei willkommen Chorus.aif'
md5 did not match decoded data, file is corrupt."

The net result is that either of the AIFF files will open and play, but only 1:32 of it exists, when the total playing time for the FLAC version is 3:25.

The original FLAC file plays just fine for the entire length of the track.

Please advise.

Thanks

[Spoon]

Re: FLAC Conversion Error

It means the flac file has errors.

[bjast]

Re: FLAC Conversion Error

Can you please elaborate, since the FLAC file plays fine as purchased from the website.

What kind of errors should I be mentioning the the website support people?

Thanks

[bjast]

Re: FLAC Conversion Error

Just realized this is not the first time I've gotten errors while converting purchased FLAC files with dbpoweramp. Here's one of several I got with other files just last week:

Encountered 'FLAC__STREAM_DECODER_READ_METADATA' in FLAC File 'Z:\Audio Downloaded\eClassical Downloads\May 15, 2011\Albinoni - Concerti a cinque, Op. 10 - 17 - Concerto a 5 in G minor, Op. 10, No. 8 - II. Largo.flac'

Most of these files played fine even though these errors appeared while converting them.

Does this help?

[bjast]

Re: FLAC Conversion Error

After even more testing I've found that I can successfully convert the original FLAC 24/96 file to 16/44 AIFF using a different conversion program than dbpoweramp. The length of this successfully converted track runs the full total length of the track without errors.

Again, I hope this helped.

Bill

[Spoon]

Re: FLAC Conversion Error

FLAC contains a md5 of the data which went into the file, without this, byte changes to the flac file could lead to corruption which you would not know about. These files are corrupted 100% (ie they are not the same as the encoded data). dBpoweramp lets you know about this, if you wish to ignore these errors:

dBpoweramp Configuration >> Codecs >> Advacned

FLAC Decoder and Corrupt FLAC File 'continue decoding on error'

[pablogm123]

Re: FLAC Conversion Error

For any reason, that file got corrupted. Perhaps, you downloaded already corrupted, or your system suffers from silence digital corruption.

If you hardware is OK and doesn't corrupt data (there are lots of stress testing programs to check you CPU, memory, hard disks...), the only plausible explanation for this case is you downloaded a corrupted file. eClassical seems to be a legal store to buy music, so that I would send them a message explaining this.

[bjast]

Re: FLAC Conversion Error

For any reason, that file got corrupted. Perhaps, you downloaded already corrupted, or your system suffers from silence digital corruption.

If you hardware is OK and doesn't corrupt data (there are lots of stress testing programs to check you CPU, memory, hard disks...), the only plausible explanation for this case is you downloaded a corrupted file. eClassical seems to be a legal store to buy music, so that I would send them a message explaining this.

1. If this is the case, why am I able to covert the FLAC file to AIFF with another conversion program, without it being shorter than the original downloaded file?

2. Does the error checking Spoon mentions above prevent the file from completely converted when it encounters the error he mentions?

[pablogm123]

Re: FLAC Conversion Error

You could ignore the error using an alternative app (for example, the official frontend for FLAC offers an option to ignore errors when decoding) or the setting suggested, of course. But the converted file will differs from the original data due to corrupted data. Perhaps there are silenced passages, missing pasages or clicks, because corrupted data will break the original waveform.

The official tool to test FLAC files and included in FLAC distribution, named FLACTester, can report where is the corrupted zone. For example, I have corruped a .flac file by changing bytes through a hex editor, and that tool reports: "ERROR_FRAME_CRC_MISMATCH @ 2m 41s"

If you paid for that music file, you should demand an error free and uncorrupted file.

[Fallsroad]

Re: FLAC Conversion Error

1. If this is the case, why am I able to covert the FLAC file to AIFF with another conversion program, without it being shorter than the original downloaded file?

2. Does the error checking Spoon mentions above prevent the file from completely converted when it encounters the error he mentions?

1. The other program you are using is ignoring the error and converting the entire file.

2. Yes. The converted file ends at the point where the corruption occurs, which is why they come up short in running time.

I have a few FLAC files DMC reported an error for, resulting in a converted file with a shorter running time. I noticed that if I listen to the original FLAC starting just before the time where the converted file ends, I can usually hear an artifact - a slight click, tick, pop or silence. For any of your files that fail to convert and throw an error, play the original back beginning a few seconds before where the converted file is truncated, and listen closely - you are likely to hear something other than just music in that space, however brief.

[bjast]

Re: FLAC Conversion Error

Thanks to all of you for your insights. I have contacted the vender I purchased the flac files from, and they issues me a full credit with an apology. Plus, I've gotten a good education from this forum about how these things work.