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Re: Interpolation schemes and SB Live!

Date1998-10-23 15:56
FromJ P Fitch
SubjectRe: Interpolation schemes and SB Live!
There was indeed a paper at ICMC on interpolation, which was why it got added
to mt to-do list.  The conclusion seemed to be that quadratic interpolation
was worthwhile, and cibic was better, but hardly worth the time.effort.
It seemed to suggest that 'proper' sinc/convolution stuff was not really
necessary.
  That is all from memory, so I may be wrong.  I had intended looking at
quadratic interpolation as an experiment to see what peopel thought.

There is a weekend coming up.....

Date1998-10-23 17:16
FromEli Brandt
SubjectRe: Interpolation schemes and SB Live!
J P Fitch wrote:
> There was indeed a paper at ICMC on interpolation, which was why it got added
> to mt to-do list.  

This would be Roger Dannenberg's "Interpolation Error In Waveform
Table Lookup", I'm guessing.  For those who don't have the procs,
the paper ought to be online some time next week.

> The conclusion seemed to be that quadratic interpolation
> was worthwhile, and cibic was better, but hardly worth the time.effort.

For the compiler and hardware used (Intel, so slow arithmetic),
there's a time/space tradeoff: for a desired SNR, higher-order
interpolation is slower but takes a smaller table.  The relationship
between table size and SNR depends heavily on the signal's brightness.

Only went up to quadratic -- I'm very curious to see how cubic
compares, actually.

BTW, I'm not sure this work applies directly to situations where the
same data is being resampled repeatedly, as in a waveguide.

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