True FLAC or fake one |
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True FLAC or fake one |
  Apr 9 2006, 00:46
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#1
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Group: Members Posts: 2 Joined: 9-April 06 Member No.: 29303  |
Hi there,
Does anyone know of a program that can verify the integrity of a flac? How can I tell if it is a real FLAC or an mp3 file that has been converted into a FLAC? Is there a program out there that will do this? Thanks 
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Apr 9 2006, 07:45
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#2
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 Group: Members Posts: 913 Joined: 10-January 05 Member No.: 18979 |
A FLAC file who's source was originally an mp3 file is still, technically, a "real" FLAC file. So it's not really the integrity of the FLAC file that you want to check (in technical terms), it's the audio data contained within.
There is only one program that I know of that can make a reasonably educated guess at whether music has been transcoded from a lossy source like mp3. Tau_Analyzer. But if I recall correctly, you probably can't scan FLAC files directly with it. Most of the time it's pretty easy to tell if an audio sample has originated from a lossy/mp3 source, just by looking at a the frequency spectrum. Lossy file compression like mp3 usually employs lowpass filtering at a frequency well below that of true CD audio. And the effect of such lowpass filtering remains apparent even after it has been transcoded. See: http://www.audiohub.org/get/fa/fa.htm + http://www.audiohub.org/get/fa/sa.htm . |
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Apr 9 2006, 08:44
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#3
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A/V Moderator Group: Members Posts: 858 Joined: 12-May 03 From: Finland Member No.: 6557 |
QUOTE (Cosmo @ Apr 9 2006, 09:45 AM)  Most of the time it's pretty easy to tell if an audio sample has originated from a lossy/mp3 source, just by looking at a the frequency spectrum. Lossy file compression like mp3 usually employs lowpass filtering at a frequency well below that of true CD audio. And the effect of such lowpass filtering remains apparent even after it has been transcoded. See: http://www.audiohub.org/get/fa/fa.htm + http://www.audiohub.org/get/fa/sa.htm . That isn't very reliable method. For some reason there are original cds come with a 16 kHz lowpass and according to cd specs the band between 20 kHz and 22.05 kHz should contain no meaningful information. |
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Apr 9 2006, 12:56
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#4
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Group: Members Posts: 407 Joined: 12-April 05 Member No.: 21399 |
QUOTE (Cosmo @ Apr 9 2006, 07:45 AM) There is only one program that I know of that can make a reasonably educated guess at whether music has been transcoded from a lossy source like mp3. Tau_Analyzer. But if I recall correctly, you probably can't scan FLAC files directly with it. True enough, but the simple way to get around this is to burn the FLAC to an ISO file, then mount it with something like Daemon Tools. I'm pretty sure that works fine. |
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Apr 9 2006, 13:31
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#5
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 Group: Members Posts: 2525 Joined: 25-July 02 From: South Korea Member No.: 2782 |
Eh? Why not just decode to .wav? If you're smart enough to burn an ISO, you're smart enough to use the command-line, IMHO.
flac -d input.flac -------------------- http://blacksun.ivyro.net/vorbis/vorbisfaq.htm
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Apr 9 2006, 13:48
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#6
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 Group: Members Posts: 526 Joined: 15-January 02 From: Warwickshire -- England Member No.: 1036 |
Because it only reads from a CD, therefore you have to either burn them to an actual disc, or mount them as a virtual drive.
Kristian //edit refering to Tau Analyzer of course This post has been edited by kritip: Apr 9 2006, 13:49 |
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Apr 9 2006, 14:06
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#7
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 Group: Members Posts: 1193 Joined: 3-September 03 From: Bergen, Norway Member No.: 8667 |
QUOTE (kritip @ Apr 9 2006, 04:48 AM) Because it only reads from a CD, therefore you have to either burn them to an actual disc, or mount them as a virtual drive. Kristian //edit refering to Tau Analyzer of course auCDtect works directly on wav files. -------------------- "ONLY THOSE WHO ATTEMPT THE IMPOSSIBLE WILL ACHIEVE THE ABSURD"
- Oceania Association of Autonomous Astronauts |
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Apr 9 2006, 14:06
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#8
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Group: Members Posts: 126 Joined: 9-March 06 From: NRW, Germany Member No.: 28371 |
Take aucdtect then.
Edit: Ah, Mr_Rabid_Teddybear was slightly faster than I. This post has been edited by LaserSokrates: Apr 9 2006, 17:54 |
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Apr 9 2006, 14:29
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#9
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Group: Members Posts: 526 Joined: 15-January 02 From: Warwickshire -- England Member No.: 1036 |
QUOTE (Mr_Rabid_Teddybear @ Apr 9 2006, 02:06 PM) auCDtect works directly on wav files. Ah, i was aware of that, but for some reason thought it was not developed anymore, and Tau Analyzer had superceded it. Upon looking further it appears i was totally wrong about that, and it is what Tau Analyzer is based upon? Good news  and serves me right for not looking harder last time I looked into it.Cheers, Kristian |
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Apr 9 2006, 14:40
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#10
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Group: Members Posts: 40 Joined: 1-March 06 Member No.: 28164 |
Tell me, if I am mistaken, but if [url=http://www.accuraterip.comAccurateRip[/url] was applied, the
AccurateRip check results actuall are also able to reveal, if a flac, or file was sourced by an original-CD or by any other non-original-CD source. |
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Apr 9 2006, 15:15
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#11
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Group: Members (Donating) Posts: 698 Joined: 31-March 04 From: NYC Member No.: 13152 |
You would have to burn an Audio CD from those files first to use AccurateRip. Then if AccurateRip reports the results as accurate, the source was lossless. However, if your results don't match those in the AccurateRip database, it could mean anything from a different CD pressing to the wrong write offset to lossy source.
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Jun 30 2008, 06:02
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#12
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Group: Members Posts: 21 Joined: 21-October 06 Member No.: 36610 |
QUOTE (ladyred @ Apr 8 2006, 20:46) Hi there, Does anyone know of a program that can verify the integrity of a flac? How can I tell if it is a real FLAC or an mp3 file that has been converted into a FLAC? Is there a program out there that will do this? Thanks There's a GUI for Tauanalyzer that decodes to wav directly. Audiochecker Home. |
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Jul 1 2008, 09:18
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#13
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Group: Members Posts: 1 Joined: 1-July 08 Member No.: 55121 |
I am having trouble decoding a flac file and I can't get it to work with many programs
flac, cog, etc. I got an error message when I tried to decode it... flac 1.1.0, Copyright © 2000,2001,2002,2003 Josh Coalson flac comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. Type `flac' for details. Antonin DvorAÃɬ°k - Masterworks Disc 1.flac: *** Got error code 0:FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC Antonin DvorAÃɬ°k - Masterworks Disc 1.flac: ERROR while decoding metadata state = 4:FLAC__STREAM_DECODER_END_OF_STREAM can anyone tell me what this means? do i have a corrupted flac? or just some program that can't decode it? it looks russian....I think......or czech....as the last characters are not coming up properly....could this be the issue? anyway...thanks dj |
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Oct 8 2010, 14:18
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#14
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Group: Members Posts: 2 Joined: 8-October 10 Member No.: 84440 |
Ill show you how i detect fake FLAC
 Software: Spectro [FLAC is supported] Homepage: http://spectro.enpts.com/ FLAC vs MP3[320kbps]:  MP3[128kbps <lol>]:  After analyze fake flac you will see same specro like on source mp3. TIP: Not always you will have 22,1KHz but that don't means its fake. When i spectred full quality human sound solo, spectro is low xP On website are good news, author will add multiple scan option
This post has been edited by Jany: Oct 8 2010, 14:20 |
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Oct 8 2010, 14:43
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#15
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Group: Super Moderator Posts: 4329 Joined: 23-June 06 Member No.: 32180 |
Why is the x-axis scale reversed?
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Oct 8 2010, 15:29
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#16
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Group: Members Posts: 2 Joined: 8-October 10 Member No.: 84440 |
QUOTE (dv1989 @ Oct 8 2010, 14:43) Why is the x-axis scale reversed? I don't know. I don't created that program 
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Lo-Fi Version | Time is now: 18th May 2013 - 10:20 |
