pvsfreeze — Freeze the amplitude and frequency time functions of a pv stream according to a control-rate trigger.
This opcodes 'freezes' the evolution of pvs stream by locking into steady amplitude and/or frequency values for each bin. The freezing is controlled, independently for amplitudes and frequencies, by a control-rate trigger, which switches the freezing 'on' if equal to or above 1 and 'off' if below 1.
fsig -- output pv stream
fsigin -- input pv stream.
kfreeza -- freezing switch for amplitudes. Freezing is on if above or equal to 1 and off if below 1.
kfcf -- freezing switch for frequencies. Freezing is on if above or equal to 1 and off if below 1.
Example 292. Example
asig in ; input ktrig oscil 1.5, 0.25, 1 ; trigger fin pvsanal asig1,1024,256,1024,0 ; pvoc analysis fout pvsfreeze fin, abs(ktrig), abs(ktrig) ; regular 'freeze' of spectra aout pvsynth fsigout ; pvoc synthesis
In the example above the input signal will be regularly 'frozen' for a short while, as the trigger rises above 1 about every two seconds.