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Transient detection +/-


I’m wondering if the transient detection function in OM-SuperVp handles the segmentation type on spectral differencing -/+ ?

Is it a mixed process ?

I’ve checked the supervp -ht (help) in the terminal and compared the list of flags in the lisp code of the transient-detection function (OMsuperVP)…

(transient-params (format nil “-OT -td_thresh ~D -td_G 2.5 -td_band ~D,~D -td_nument 10.0 -td_minoff ~Ds” treshold minfreq maxfreq minoffset))

Well, FIRST there is no sign of the -td_minren :

minimum relative energy difference an attack has to produce to be detected as an attack. The relative energy difference is calculated as the energy difference between the transient bins after the attack and before the attack normalized by the total energy difference.

Which nearly corresponds to the A.S. online doc :

Positive and Negative Differencing

Positive spectral differencing detects a quick increase of energy, as in the case of an attack for instance.

Negative spectral differencing detects a quick decrease of energy, as in the case of the end of a note.

THEN in the output sdiff file from the process with the transient-detection function (.omp file attached) there’s a reference to :

1TYP { 1MTD XTRD {rel_energy_diff, rel_maxamp} 1FTD 1MRK { XTRD transient_descriptor; } }

Thank you