Is thee proper documentation of the CROSS2 opcode ???

It is mentioned in the manual, yes, but does not say what the arguments
mean...

The manual says :

asig	cross2	ain1, ain2, ilen, iovl, iwin, kbias

Cross synthesis between the two audio signals. (New in Csound 3.47)

I guess ain1,ain2 are the carrier and modulator waves...
- ilen = lenght ?
- iovl =  ? 
- iwin = ?
- kbias = ?

p.s. :   can someone briefly explain how basic (kraftwerk-ish) vocoding is
done ??
I think it is done by filtering out a few harmonic partials of a wave
(someone talking) and use them to
control the volume of the according harmonics of the signal to be vocoded .
wrong ? right ?

David.