| 摘要 |
A method and apparatus for data processing by linear prediction. The second order prediction error filter (PEF) coefficients for the data are estimated in a PEF estimator (14) so as to approximate the pair of coefficients occurring in a binomial factor of the z transform of a sequence of higher order PEF coefficients of the data. The binomial coefficient pair is associated with a formant in the spectrum of the data. The PEF coefficients are utilized to control filters (11, 12, 13)so as to modify the spectrum of the data according to changes in the data. The estimator (14) and filter arrangement (11, 12, 13) are effectively a data adaptive filter. A process of successive approximation is used to isolate the main formant and also to attenuate it in a data stream which is transmitted to a further similar cascaded module in the apparatus whereby the same process is performed to isolate and remove a further formant. Buffers (17-20) thus contain PEF coefficient pairs associated with each formant in the input data. |
