Method and apparatus for speech generation from phonetic codes
First Claim
1. The method of generating speech comprising the steps of:
- storing a plurality of digitized waveforms representing phonemes of voiced and fricative types;
assigning an articulation type to each phoneme;
inputting a series of phonetic codes representing speech wherein the series of phonetic codes identify a succession of phonemes;
for each phonetic code, generating an allophone by selecting at least one stored digitized center waveform corresponding to such phonetic code, selecting a stored digitized initial waveform according to the articulation type of the preceding phoneme in the succession, selecting a stored digitized final waveform according to the articulation type of the following phoneme in the succession, and serially combining the selected initial, center, and final waveforms; and
concatenating a series of allophones corresponding to the series of phonetic codes for producing a digital representation of the speech; and
producing audible speech from the digital representation of speech.
1 Assignment
0 Petitions
Accused Products
Abstract
Speech generation from phonetic code is carried out by a microcomputer based system which stores digitized waveform segments and appropriately joins the segments and outputs them to a digital to analog converter and then to a speaker. An allophone is generated for each phoneme designated by the phonetic codes according to the articulation type of each adjacent phoneme. Each phoneme is classified as neutral, labial, glottal, or medial according to its effect on the articulation of adjacent phonemes. Each phoneme is characterized by at least one center waveform dependent on the phonetic code, and an initial waveform and a final waveform, each of which depend on the phonetic code and the articulation type of the neighboring phoneme. Tables of waveform pointers are accessed according to phonetic code and articulation type, and other tables provide articulation types, times of each waveform portion, transition rate, fricative state, and pitch for each phonetic code. Adjacent waveforms are gradually blended together. Continuously varying center waveforms are afforded by indexing through successive waveform pointers at a given rate during the center phoneme period, the rate and the period being retrieved from the tables.
40 Citations
29 Claims
-
1. The method of generating speech comprising the steps of:
-
storing a plurality of digitized waveforms representing phonemes of voiced and fricative types; assigning an articulation type to each phoneme; inputting a series of phonetic codes representing speech wherein the series of phonetic codes identify a succession of phonemes; for each phonetic code, generating an allophone by selecting at least one stored digitized center waveform corresponding to such phonetic code, selecting a stored digitized initial waveform according to the articulation type of the preceding phoneme in the succession, selecting a stored digitized final waveform according to the articulation type of the following phoneme in the succession, and serially combining the selected initial, center, and final waveforms; and concatenating a series of allophones corresponding to the series of phonetic codes for producing a digital representation of the speech; and producing audible speech from the digital representation of speech. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. In a speech generation apparatus having a memory containing tables of waveform pointers and tables of phoneme parameters, the method of generating speech comprising the steps of:
-
storing in the memory digitized waveforms for use as initial, center and final waveforms; inputting a phonetic code sequence representing speech; repetitively and sequentially executing an input routine and an output routine for progressively processing phonetic codes; on successive passes through the input routine entering branches for selecting from the tables waveform pointers, the waveform pointers identifying initial, center and final waveforms for a current phoneme; and on successive passes through the output routine, retrieving stored digitized waveforms in accordance with the selected waveform pointers, and generating a digital representation of speech corresponding to the phonetic code sequence by combining the retrieved waveforms. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. Apparatus for generating speech in response to input codes including:
-
a memory for storing phoneme waveforms and phoneme articulation types; input means for receiving a string of phonetic codes representing speech; context sensitive means for generating allophones for respective received phonetic codes including means for selecting center waveforms as dictated by corresponding phonetic codes and for selecting initial and final waveforms for each allophone according to the respective articulation types of preceding and subsequent phonemes; waveform transition means for blending selected adjacent waveforms of each allophone and consecutive allophones; and output means responsive to the blended waveforms for producing audible speech corresponding to the input string. - View Dependent Claims (24, 25, 26)
-
-
27. Apparatus for generating speech in response to input codes comprising a microcomputer based apparatus including:
-
a buffer for holding a string of phonetic codes representing a succession of phonemes for at least a portion of desired speech; a read only memory (ROM) containing operating code, a plurality of digitized waveforms, a table of articulation types for each phonetic code and addressable by the phonetic code, and tables of waveform pointers addressed by the phonetic codes and articulation types; pointer means for successively designating each phonetic code, in turn, as a current phonetic code and for each current phonetic code designating a center phoneme, a preceding phoneme and a following phoneme; means for looking up in the table of articulation types the types of the preceding and the following phonemes; means for looking up the waveform pointers for the initial, center, and final waveforms for each current phonetic code, in turn using the articulation types and the phonetic code to define a succession of waveforms; and means for retrieving waveforms identified by the waveform pointers and joining the retrieved waveforms for each phonetic code to generate a string of context sensitive allophones representing the desired speech. - View Dependent Claims (28, 29)
-
Specification