US 8,019,603 B2 · Apparatus and method for enhancing speech intelligibility in a mobile terminal

Abstract

An apparatus and a method for enhancing speech intelligibility in a mobile terminal. A complex spectrum calculator calculates complex spectra of one input frame of an input speech signal by Fourier transform, a speech level calculator calculates its instant levels, an average speech level calculator calculates an average speech level of the speech frame using the instant levels, if the input frame is a speech frame, a scaling factor calculator calculates scaling factors by comparing the average speech level with the instant levels, an HPF characteristic calculator calculates amplitude characteristics using the scaling factors, a HPF high-pass-filters the complex spectra using the amplitude characteristics, a synthesizer converts high-pass-filtered signals to time signals by inverse Fourier transform and synthesizes the time signals, and a combiner outputs an enhanced intelligibility speech signal by combining the synthesized time signal with the input frame.

Claims12

Dependent claims

An apparatus for enhancing speech intelligibility in a mobile terminal, comprising:

a complex spectrum calculator for calculating complex spectra of one input frame of an input speech signal by Fourier transform;
a speech level calculator for calculating instant levels of the input frame;
an average speech level calculator for, when the input frame is a speech frame, calculating an average speech level of the speech frame using the instant levels;
a scaling factor calculator for calculating scaling factors by comparing the average speech level with the instant levels;
a High Pass Filter (HPF) characteristic calculator for calculating amplitude characteristics for high-pass-filtering using the scaling factors;
a HPF for performing high-pass-filtering on the complex spectra based on the amplitude characteristics;
a synthesizer for converting high-pass-filtered signals to time signals by inverse Fourier transform and synthesizing the time signals;
and
a combiner for outputting an enhanced intelligibility speech signal by combining the synthesized time signals with the input frame.

6 more elements

A method for enhancing speech intelligibility in a mobile terminal, comprising:

calculating complex spectra of one input frame of an input speech signal by Fourier transform;
calculating instant levels of the input frame;
calculating, when the input frame is a speech frame, an average speech level of the speech frame using the instant levels;
calculating scaling factors by comparing the average speech level with the instant levels;
calculating amplitude characteristics for high-pass-filtering using the scaling factors;
performing high-pass-filtering on the complex spectra based on the amplitude characteristics;
converting high-pass-filtered signals to time signals by inverse Fourier transform and synthesizing the time signals;
and
outputting an enhanced intelligibility speech signal by combining the synthesized time signals with the input frame.

6 more elements

Dependencies are inferred from the claim text.

Apparatus and method for enhancing speech intelligibility in a mobile terminal

Life of this patent

Apparatus and method for enhancing speech intelligibility in a mobile terminal

Life of this patent

Abstract

Claims12