DEVICE FOR PREVENTING SPEECH QUALITY FROM DETERIORATING IN TEXT TO SPEECH SYSTEM, ESPECIALLY IN RELATION TO DIVIDING INPUT EXCITATION SIGNALS OF A SPEECH SYNTHESIS FILTER BY DISTINGUISHING VOICED SOUNDS FROM VOICELESS SOUNDS TO PREVENT SPEECH QUALITY OF THE VOICELESS SOUNDS FROM DETERIORATING

摘要

PURPOSE: A device for preventing a speech quality from deteriorating in a TTS(Text To Speech) system is provided to store residual signals of voiceless sounds in a DB, and to perform a voiceless sound synthesis to be identical with original signals by using the residual signals when controlling inputs of a speech synthesis filter according to voiced sound and voiceless sound information, thereby preventing speech quality deterioration. CONSTITUTION: A language processor(201) outputs a unit sequence for speech synthesis by processing an inputted sentence. A rhythm controller(202) synthesizes information of a synthetic unit string with speech signals, outputs the synthesized signals, and processes a rhythm on the unit string. A speech synthetic filter(203) receives the information on the synthetic unit string to synthesize with voiced sounds and voiceless sounds, and carries out a voiceless sound synthesis. A synthetic DB(204) supplies parameters for rhythm controlling and speech synthesizing. A voiced/voiceless sound control memory(205) supplies a signal for voiced sound/voiceless sound input controlling. A voiceless sound residual signal DB(206) supplies residual signals of the voiceless sounds for voiceless sound synthesizing.