Recognizing and locating method for abnormal sound in public places

Abstract

The invention relates to a recognizing and locating method for abnormal sound in public places, which belongs to the technical field of audio signal processing. The method uses a double-threshold algorithm and a Welch method to estimate a power spectrum to judge whether the abnormal sound exists in the public places. Feature sequence signals of the abnormal sound are converted into a spectrogram of a time-frequency domain, and problems of feature extraction and classification recognizing of the abnormal sound are solved by using the sparse coding sound recognition technology sensed by hearing. In order to restrain effects of pulse noise in background noise on the abnormal sound locating, non-linear transformation is introduced, and cross-correlation function peak capacity of the abnormal sound is improved. A traditional harmonic balance (HB) weight function is modified, and weight changes caused by low signal-to-noise ration are lowered. Multi-frame data weight processing is introduced, a novel HB weight generalized cross correlation algorithm is suitable for capacity for processing abnormal sound locating in complex acoustic environments in the public places. Due to the fact thatthe method is combined with the sparse coding sound recognition technology based on hearing sense and the modified sound locating technology of time difference of arrival, sound information accompanied with abnormal events can be utilized better, and intelligent level of a monitoring system in the public places can be improved.

Description

technical field [0001] The invention belongs to the technical fields of audio signal processing, pattern recognition and array signal processing. Background technique [0002] Public places refer to various places where the public engages in social life. Various dangerous incidents, traffic incidents, criminal incidents, etc. that occur in people's daily production activities in public places are closely related to the safety of people's lives and property. At present, video surveillance platforms in public places with video surveillance as the core technology have been built to varying degrees in various places, which have played a positive role in reducing crime rates, improving the efficiency of solving crimes and scientific evidence collection. However, most of the existing video surveillance platforms implement manual surveillance plus video surveillance in important places and important time periods. In general places, video cameras are used for video surveillance. ...

AI Technical Summary

Problems solved by technology

Under the premise of satisfying the maximum likelihood criterion, this kind of method aligns the beam formed by the microphone array with the abnormal sound source by means of search, so as to obtain the maximum output power. When all searches are used, the calculation amount is very large. The iterative method is extremely sensitive to the selection of the initial value, and often fails to meet the expected requirements in practical applications

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