Kokusai Denshin Denwa Co., Ltd.

Kokusai Denshin Denwa Kabushiki Kaisha

Akira Kurematsu

Seishi Kitayama

Fumihiro Yato

Kazunori Konishi

Kazuo Hasuike

Junso Tamura

Hikoichi Ishigami

In a speech transmission or storage system using LPC parameters and a Baseband Signal derived from the prediction error signal, the synthesis excitation signal is formed from the baseband plus high-frequency regeneration, which is then spectrum-flattened for proper synthesis.

Voice encoding and decoding device

In a speech analysis-synthesis system for the narrow band transmission of a speech signal, speech is separated into a plurality of spectrum information (K.sub.i), average (V.sub.0) of linear prediction error signal, pitch period (L), voiced/unvoiced decision signal (V/UV), a pseudo exciting signal (I) which is a part of a linear prediction error signal or an impulse response of the same, and a frame information which determines the interval and the duration of the spectrum analyzation, then, in a receive side, the product of said pseudo excitation signal (I) and said pitch period (L), a white noise is switched according to said voiced/unvoiced decision signal (V/UV), and the output of the switch is applied to a synthesis filter which attaches correlation components to an input signal according to spectrum information (K.sub.i) to provide synthesized speech.

Speech analysis-synthesis system

In a message communication system and process, a character string with a plurality of characters is encoded into a compact code, which is transmitted to a reception side. At the reception side, the compact code is decoded to an original character string. Thus, the amount of information to be transmitted is fairly reduced as compared with the transmission in which each character is encoded. Preferably, a combination of a word and a `space` code following the word is encoded to a single compact code. The compact code may also encode a combination of a plurality of words. Some particular control codes are defined for converting a small character to a capital character, or vice versa, and designating special code like period '.', quotation mark '?', etc.

Reduction of message length in a communication system

A control system for a line scanning type output unit which is made capable of generating both facsimile and text by setting the scanning density in the sub scanning direction at a higher value, but within the allowable error range, to match both the scanning density of the facsimile and the pitch of the text, by providing two types of clocks for composing image signals, i.e. a fax clock which matches with the resolution in the main direction of the facsimile and a text clock which matches with the pitch of the main scanning direction of the text, so that the fax clock may be employed to compose an image signal which is fed to the output unit for facsimile output and the text clock may be employed to compose image signal which is fed to the output unit for text output.

Control system for a line scanning type output unit

A system for detecting the pitch of a voice signal, in which a plurality of pitch searching periods are determined so that pitch components of multiple relationship are not included in each of the pitch searching periods, and in which after detecting a pitch searching period including the pitch from the pitch searching periods, the pitch searching periods are adaptively shifted in a mannger to follow the change direction of the pitch predicted from the result of detection of the detected pitch.

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Yokohama, Japan

Akira Kurematsu