Method for generating sound masking signal based on time reversal

Abstract

The invention relates to a method for generating a sound masking signal based on time reversal. In the method, a corresponding sound masking signal is acquired according to a target sound source signal and has a long-time amplitude spectrum similar to that of the target sound source signal and extremely low speech intelligibility. The method comprises the following steps of: picking up the target sound source signal by using a microphone or a microphone array and performing preprocessing to acquire a clean target sound source signal; performing framing based on a specific time window length according to the acquired target sound source signal; and performing time reversal on a time domain of each frame of signal according to y(t)=x(-t) to acquire the sound masking signal corresponding to a target sound source, wherein x(t) represents a frame of signal, and the y(t) represents an output signal of the frame. The time reversal sound masking signal has the long-time amplitude spectrum similar to that of the target sound source signal; the method has advantages in energy masking; and the time reversal sound masking signal is completely unintelligible or is partially intelligible and cannot become a new interference sound source.

Description

technical field [0001] The invention relates to a method for generating a sound masking signal, in particular to a method for generating a sound masking signal based on time reversal. Background technique [0002] Studies have shown that speech is the most disturbing sound signal in the room, and the speech intelligibility of speech signals will reduce work efficiency. In some occasions, due to the high speech intelligibility, the privacy of personal calls cannot be guaranteed, and there is an urgent need for a method that can reduce the speech intelligibility and protect the privacy of personal calls. Sound masking refers to the method of adding a natural or artificially synthesized sound into the environment, covering the sound of the target sound source through auditory masking, and reducing the intelligibility of the target sound source signal. At present, acoustic masking technology based on acoustic masking signals is considered to be one of the necessary measures to ...

AI Technical Summary

Problems solved by technology

In the existing sound masking signal generation methods, their masking signal sources are generally noise signals, such as: white noise, pink noise, air-conditioning noise and various noises artificially generated, but the noise signal has no correlation with the target sound source signal. The masking efficiency is very low, which requires the noise energy at the receiving point to be much greater than the target sound source signal energy to reduce the speech intelligibility of the target sound source

The problem is, too much noise energy can add to the annoyance of the sound, making it unbearable

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