Multichannel zero-crossing-interval pitch estimation

A method for estimating the pitch of voiced speech is presented, based on the following operations: multichannel band-pass filtering; envelope extraction; low-frequency emphasis and DC-level removal; bin analysis of zero-crossing interval times of the yielded waveforms; smoothing of the resulting histogram to give the pitch-period estimator function for a single frame of speech. Since most of these steps are time-serial, a hybrid analog-digital realization suggests itself which makes real-time applications feasible.