SPEECH ENHANCING DEVICE, METHOD, PROGRAM, AND RECORDING MEDIUM OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a speech enhancing technique capable of reflecting the characteristic of an easily audible speech and improving clarity without requiring preliminary tuning of a control amount against noises having various characteristics.SOLUTION: A speech enhancing device calculates a power ratio of a speech spectrum to a noise average spectrum using the speech spectrum, a formant frequency, and the noise average spectrum, estimates a target power ratio which is a power ratio at which easy audibleness is achieved corresponding to a target clarity score in a formant greatly affecting the clarity in speech on the basis of a relationship between the previously acquired easy audibleness in speech and the power ratio, and includes a spectrum conversion part for converting the speech spectrum into a formant enhancement spectrum in the formant frequency on the basis of the target power ratio and the power ratio; and a speech synthesis part for synthesizing enhancement speech data s(t) on the basis of the formant enhancement spectrum.