🚀 go-pugleaf

In article <1737@draken.nada.kth.se>, d88-jwa@nada.kth.se (Jon W{tte) writes:
> The solution is to "fake" a higher sample pitch, causing the CD to
> interpolate the samples between the actual samples. The waveform
> now looks like this: (4-fold oversampling)
. . .
> And requres much less steep filters (typically 30 dB/octave) which means
> no phase shifting. Good CD players use more bits in the output stage
> than is recorded on the CD (i.e. 18 or 20 instead of 16) to get better
> resolution in the oversampling if the variation between each sample is
> small (i.e. low output) so that they don't have to interpolate 47 -> 48
> as 47 47 47 48 48 but could use 47 47.25 47.5 47.75 48 and thus get a
> smoother, cleaner output.

	My DSP professor discussed CD oversampling and his explanation was
different from the above in the details.  Oversampling does not directly
interpolate the sample values to 47 47.25 47.5, etc.  Instead, 0's are
inserted as appropriate between samples.  The LPF takes care of recovering
the signal.  There is no distortion at all.

Dzung Hoang
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