Speech information transmission method and system

Abstract

Speech information communicating method and apparatus for transmitting speech information through a transmission system having a low bit rate transmission capacity such as Telex to a receiver station for reproduction. The apparatus comprises at the side of transmitter station a speech recognition device for extracting by high data compression a character train corresponding to syllable units or phonetic symbol from an input speech and simultaneously determining accent types of words or phrases contained in a character train, and a code converter for encoding the extracted character train and the identified accent type in the form of Telex code, unoccupied Telex codes being allotted to the accent type codes and for producing an encoded speech information signal including a time series of character codes having the accent type identifying codes inserted therein. The receiver station includes a decoder for decoding the encoded speech information signal from a transmission channel into the character code train and the accent identifying code, a signal processing circuit for converting the derived character code train into a syllable-based time series signal while preparing accent type identifying signal from the accent identifying code, thereby to produce a speech synthesis control signal, a speech synthesizer for reading out voice waveform signals to be synthesized from a voice waveform storing memory in accordance with the speech synthesizing control signal, and converter for converting the readout voice waveform signal into a corresponding audible speech signal. The output from the encoding circuit of the transmitter can be once recorded on a Telex tape and transmitted to the receiver later on by an automatic Telex sender system. At the receiver station, the received speech code information can be recorded and reproduced later on by a speech decoding apparatus provided with a tape reader having a speech restoring function.