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specdiff

Finds the positive difference values between consecutive spectral frames.

⚠ Deprecated

This opcode belongs to the deprecated constant-Q spectral family that uses w signals. Csound keeps it for compatibility and does not name a direct replacement.

Syntax

wsig = specdiff(wsigin)

wsig specdiff wsigin

Performance

wsig -- the output spectrum.

wsigin -- the input spectra.

Finds the positive difference values between consecutive spectral frames. At each new frame of wsigin, each magnitude value is compared with its predecessor, and the positive changes written to the output spectrum. This unit is useful as an energy onset detector.

Examples

  wsig2    specdiff    wsig1         ; sense onsets 
  wsig3    specfilt    wsig2, 2      ; absorb slowly
           specdisp    wsig2, 0.1    ; & display both spectra
           specdisp    wsig3, 0.1

See also

specaddm, specfilt, spechist, specscal