[LAU] Lossy audio to lossless format

[Tim Goetze]

[Egor Sanin]
>Now the question is whether it is possible to analyze an
>audio file encoded in a lossless format and
>determine if it existed as a lossy file in a
>previous life?

The lowpass/antialiasing filters used for most audio productions
usually operate very close to the Nyquist limit.  Those employed in
lossy audio data compression often (but not always) are set to a lower
cutoff frequency.  On a spectrogram, their effect is visible as a
total absence of energy above, say, 20kHz or lower.

Cheers, Tim