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octdown, noctdft

   dsig  octdown   xsig, iocts, isamps[, idisprd]
   wsig  noctdft   dsig, iprd, ifrqs, iq[, ihann, idbout, idsines]


idisprd (optional) - if non-zero, display the output every idisprd seconds. The default value is 0 (no display).

ihann, idbout, idsines (optional) - if non-zero, then respectively: apply a hanning window to the input; convert the output magnitudes to dB; display the windowed sinusoids used in DFT filtering. The default values are 0,0,0 (rectangular window, magnitude output, no sinusoid display).


octdown - put signal asig or ksig through iocts successive applications of octave decimation and downsampling, and preserve isamps down-sampled values in each octave. Optionally display the composite buffer every idisprd seconds.

noctdft - generate a constant-Q, exponentially-spaced DFT across all octaves of the multiply-downsampled input dsig. Every iprd seconds, each octave of dsig is optionally windowed (ihann non-zero), filtered (using ifrqs parallel filters per octave, exponentially spaced, and with frequency/bandwidth Q of iq), and the output magnitudes optionally converted to dB (idbout non-zero). This unit produces a self-defining spectral datablock wsig, whose characteristics are readable by any units that receive it as input, and for which it becomes the template for output. The information used in producing this wsig (iprd, iocts, ifrqs) is passed via the data block to all derivative wsigs, and is thus available to subsequent spectral operators if needed.


 asig   in            ; get external audio
 dsamp  octdown  asig, 6, 180, 0     ; downsample in 6 octaves
 wsig1  noctdft  dsamp, .02, 12, 33, 0, 1, 1 ; and calc 72-point dft (dB)

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