To correct an off-centre disc, one would need a time-stretch routine with the amount of stretch varying according to a sine wave law. The intensity, phase and frequency of the sine wave would have to be adjustable in real time so that the correction could be set by ear.
Yes and no. Eccentric wow is periodic but also variable in amplitude. The amplitude change depends on the pitch of the grooves, so may be predictable or may be a function of the music content. The frequency of the time variation is exactly one cycle per rotation. The phase is, as Don says, a parameter determined by ear.
Mike -- mrichter@xxxxxxx http://www.mrichter.com/