---- Albert Cahalan skrev ----
> On 6/26/17, David Rowe <da...@rowetel.com> wrote:
>
> > I'm currently using a 2D DCT approach (bit like JPG) to code a version
> > of the spectrum. VQ could also be used.
This sounds a bit like cepstral analysis, which was invented partly to analyze
harmonics. Played around with it in my master's thesis.
> > We don't really need to reg-generate the upper 4kHz as it doesn't take
> > many bits to encode it faithfully (perhaps 20% more than the first
> > 4kHz). The log(f) response of the ear means there isn't much info there
> > we can actually perceive.
>
> You might try a non-linear scaling prior to the 2D DCT.
> Squish and stretch it as you would if making a log-normal graph.
> That is, so that your spectrum plot shows octaves with equal spacing,
> such that you could line it up with a musical keyboard.
Mel or Bark spacing may be more appropriate. Unfortunately harmonics won't line
up as nicely if you do either of those
/Tomas
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