1. A process for extracting pitch information from a digitized speech signal comprising the steps of: selecting a plurality of values .tau..sub.i, each value representative of a frequency within the speech spectrum and logarithmically spaced within said spectrum; segmenting the digitized signal into frames of predetermined length; generating, for each frame and each value of pitch period .tau..sub.i, a score W.sub.t (i) representative of the cost of the cheapest sequence of pitch values ending with .tau..sub.i at time t; generating for each frame an array P.sub.t (i) representative of the index of the immediately preceeding pitch period in said cheapest sequence, and selecting for the current frame that .tau..sub.i for which W.sub.t (i) is minimum.