Abstract: Fixed-format and coded control informations are received for generating announcements. The coded control informations select synthetic speech information items from a store. A speech generator under control of the control items forms a composite speech message. For a message containing both fixed items and variable items, fixed items are encoded in enriched phoneme notation. Variable items are encoded in straight phoneme notation. Items are provided in multiple versions. Each version has a respective different prosody pattern of pitch and/or rhythm of its phoneme sequence, and is selected by a multivalued context symbol adjoined or implicit to the associated control information element.

Abstract: A method and an apparatus for manipulating an input signal (e.g., an audio equivalent signal) having a specific length to form an output signal having a different length. A chain of successive overlapping time windows is positioned with respect to the input signal; segment signals are derived from the input signal and the segment signals; and the output signal is synthesized by chained superposition of a sequence of the segment signals. Each of the windows (except for the first window in the chain) is positioned by incrementing a position of the window from a corresponding position of a preceding window in the chain by a time interval. That time interval is substantially equal to a principal period of periodicity of a portion of the input signal with respect to which the window will be positioned. The sequence of segment signals is derived from the segment signals by performing at least one of repeating and suppressing one or more of the segment signals.

Abstract: Method and apparatus for manipulating an input signal (e.g. an audio (equivalent) signal) to obtain an output signal having a different pitch and/or duration. The method includes (a) positioning a chain of successive overlapping time windows with respect to the input signal; (b) deriving segments signals from the input signal and the windows; and (c) synthesizing the output signal by chained superposition of the segments signals. Each of the windows (except for the first window in the chain) is positioned by incrementing a position of the window from a corresponding position of a preceding window in the chain by a time interval. The time interval is substantially equal to a local pitch period for a portion of the input signal with respect to which the window is positioned. Accordingly, each of the windows of the chain (except for the first window) is positioned so that it begins at a predetermined time interval from a preceding window in the chain.

Abstract: LPC-synthesizing device, in which a modulation of the synthesized signal with a window signal is used to reduce the buzz which is characteristic for such devices. This window signal has an amplitude which initially increases gradually from substantially zero value to a constant value, and then decreases gradually from the constant value to substantially zero value. As a result of this modulation the signal in the transition between two segments of voiced speech is forced to zero thereby eliminating any transition discontinuities, the existence of which causes the buzz.

Abstract: In a formant speech analysis synthesis system, formant extraction to control a recursive digital all-pole filter encounters the problem that pole-pairs are not orderly arranged and that real poles may occur which are not representative of formants. The problem is solved by transforming the coefficients of the second-order sections of the filter to coefficients which can be easily ordered and by means of which it is simple to assign formants to the real poles.