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Topic: is it possible to detect mp3 sourced CDs? (Read 25667 times) previous topic - next topic

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  • sony666
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is it possible to detect mp3 sourced CDs?
Reply #25
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The frequency analysis is also an accurate way of telling if a CD is mp3 sourced: any original disc always reaches fully 22050Hz without cutting the 20+Khz area.

That's absolutely not true, I have a couple of original CDs from the early 80's that are lowpassed at 18KHz, for example (Dio - Holy Diver and The Last in Line)

Nevertheless, on most mp3 based files you might note a clear line at 16KHz, and not a lot of content above it.
  • Last Edit: 14 October, 2003, 01:30:43 AM by sony666

  • Jojo
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is it possible to detect mp3 sourced CDs?
Reply #26
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Nevertheless, on most mp3 based files you might note a clear line at 16KHz, and not a lot of content above it.

This is not exactly true, though. I have original CD's that have no frequencies higher than 16 kHz…for instance, some songs of the "Bloodhound Gang", but also newer peaces!
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  • MuMart
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  • Banned
is it possible to detect mp3 sourced CDs?
Reply #27
A good realtime spectrascope is an easy way to tell (baudline is good on linux,
there are probably plenty of winamp vis plugins for this).

MP3 has a very "steppy" frequency response due to freq-domain quantization,
and it is very easy to tell visually when PCM has been through an mp3 encoder.

Cheers,
Martin

  • Cyaneyes
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is it possible to detect mp3 sourced CDs?
Reply #28
Another thing to consider: if a show was recorded with a DAT at 32khz, the frequencies will cut off at 16.  So a cut at 16khz isn't always a 100% reliable clue.

  • cd-rw.org
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is it possible to detect mp3 sourced CDs?
Reply #29
Sorry to bounce an ancient thread, but...

Is just my imagination, or was the some time ago (perhaps a year or so?) a software introduced on this site which was used to analyze audio/cd content and "guess" if the audio has been lossly compressed at some point of production?

I have this feeling that I saw this kind of program some time ago, but I am now unable to find it. The search terms just don't cut it:" mp3, lossy, compression, etc.".

Anyone recall this one? I want to wipe clean my CD-R collection of lossy stuff.

  • M
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is it possible to detect mp3 sourced CDs?
Reply #30
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Sorry to bounce an ancient thread, but...

Is just my imagination, or was the some time ago (perhaps a year or so?) a software introduced on this site which was used to analyze audio/cd content and "guess" if the audio has been lossly compressed at some point of production?

I have this feeling that I saw this kind of program some time ago, but I am now unable to find it. The search terms just don't cut it:" mp3, lossy, compression, etc.".

Anyone recall this one? I want to wipe clean my CD-R collection of lossy stuff.
[{POST_SNAPBACK}][/a]

Sure. It's [a href="http://www.true-audio.com/]auCDtect (command line, freeware)/Tau Analyzer (shareware, GUI-based)[/url].

    - M.
  • Last Edit: 09 February, 2005, 01:55:34 AM by M

  • esa372
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is it possible to detect mp3 sourced CDs?
Reply #31
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I want to wipe clean my CD-R collection of lossy stuff.
Sure. It's auCDtect (command line, freeware)/Tau Analyzer (shareware, GUI-based).
auCDtect seems to be a great program, but (just so you know) I found three factory-pressed CDs that auCDtect reported as possibly being MPEG.  So be careful; it's not 100% accurate.

Here's the link to my findings:
http://www.hydrogenaudio.org/forums/index....ndpost&p=269169
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