JPH06351095A - Method for generating reverberation - Google Patents

Abstract

PURPOSE:To provide an excellent reverberation generating method capable of generating natural reverberation whose frequency characteristic is changed along with the lapse of time without being influenced by both the characteristics of a measuring system and noise at the time of measurement. CONSTITUTION:This reverberation generating method is provided with a pulse train generating means 3 for generating a pulse train to become a source for the coefficient of a FIR filter from an impulse response 2 including either the characteristics of a measured measuring system or noise, a band dividing means 4 for dividing the pulse train into the time sequential data of plural frequency bands, a band-sorted attenuation compensating means 6 for compensating the attenuation of a waveform at every band, based on the attenuation coefficients of the respective frequency bands obtained from a reverberation time frequency characteric 5 and a band-sorted waveform resynthesizing means 7 for resynthesizing respective band waveforms after compensation of the attenuation as a waveform in the whose band and characterized by convolving an output 8 from the means 7 with musical sound data from a sound source 9 and outputting reverberation sound 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverberation sound generating method for reverberation variable or improving a sound field in a music hall, a theater or the like.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show the configuration of a conventional reverberation sound generating apparatus using an FIR filter (non-recursive filter).

In FIG. 3, 31 is a sound source, 32 is a convolution device using an FIR filter, and 33 is its FI.
The reverberation sound 34 is generated by convolving the impulse response data measured in an actual music hall or the like, which is set as a coefficient in the R filter, and the sound source 31 and the impulse response data 33.

In FIG. 4, 41 is a sound source, 42 is a convolution device using an FIR filter, and 43 is its FI.
Pulse train data set as a coefficient in the R filter,
Reference numeral 44 is a frequency characteristic correction circuit, and a reverberation sound 45 is generated by convolving the sound source 41 and the pulse train data 43.

[0005]

However, in the reverberation sound generation method by the conventional reverberation sound generation device, for example, as shown in FIG. 3, when the measured impulse response is used as the coefficient of the FIR filter, a speaker or a microphone is used. There is a problem in that it is affected by the characteristics of the measurement system such as the above and noise such as background noise. Further, as shown in FIG. 4, when a pulse train is used as a coefficient, the characteristics of the measurement system and the influence of noise are eliminated, but there is no information on the frequency characteristic, and the sound quality is particularly hard due to the influence of the high frequency range. Therefore, the frequency characteristic is corrected by applying a low-pass filter with an equalizer or the like, but this correction is only the final stage correction, and there is a problem that a natural reverberation sound whose frequency characteristic changes with time cannot be generated. It was

The present invention solves the above-mentioned conventional problems, and it is possible to generate a natural reverberation sound whose frequency characteristic changes with time without being affected by the characteristics of the measuring system and noise during measurement. The present invention provides an excellent reverberation sound generation method.

[0007]

In order to achieve the above object, the present invention provides a reverberation sound generating method for convolving musical tone data obtained from a predetermined sound source and measured impulse response to convolve and output a reverberation sound. Therefore, from the measured characteristics of the measurement system and the impulse response containing noise, the FIR
A pulse train generation unit that generates a pulse train that is a basis of a filter coefficient, a band division unit that divides the pulse train into time series data of a plurality of frequency bands, and an attenuation coefficient of each frequency band obtained from reverberation time frequency characteristics In addition, there are band-by-band attenuation correction means for performing attenuation correction on the waveforms for each band, and band-by-band waveform recombining means for again synthesizing each band waveform after this attenuation correction as a waveform of all bands, It is characterized in that the output of the different waveform resynthesizing means and the musical tone data are convolved and integrated to output a reverberant sound.

[0008]

Therefore, according to the present invention, from the measured characteristics of the measurement system and the impulse response containing noise,
After performing attenuation correction based on the attenuation coefficient of each frequency band obtained from the reverberation time frequency characteristic for each band of the pulse train, by combining these, by performing musical sound and convolution reproduction,
A natural reverberation sound can be reproduced.

[0009]

FIG. 1 is a conceptual block diagram showing a reverberation sound generation system according to an embodiment of the present invention, and FIG. 2 is a signal waveform conceptual diagram showing the reverberation sound generation system of the present invention. In FIG. 1, 1 is an impulse response correction device and 10 is a convolution device. The impulse response correction device 1 includes a pulse train generation means 3 for extracting a pulse train from the measured impulse response 2, a band division means 4 for dividing the pulse train into waveforms for each band, and a reverberation time frequency characteristic 5 for each band. Further, it is composed of band-by-band attenuation correction means 6 for correcting the attenuation characteristic and waveform re-synthesis means 7 for re-synthesizing the corrected band waveforms.

That is, at the output of the waveform recombining means 7 of the impulse response correction device 1, the impulse response 8 which is attenuation-corrected for each band is obtained. By using the data as a coefficient of the convolution device 10 and performing convolution reproduction with the sound source 9, a natural reverberation sound 11 reflecting the reverberation time frequency characteristic can be reproduced.

The operation of the above configuration is shown in FIGS.
To explain. First, in FIG. 1, the impulse response 2 including the measured characteristics of the measurement system and noise is measured.
From FIG. 2 (a), the FI is generated by the pulse train generation means 3.
A pulse train (FIG. 2B) that is the basis of the R filter coefficient is generated. Next, this result is divided into time series data of a plurality of frequency bands by the band dividing means 4 (FIG. 2 (c)), and then the reverberation time frequency characteristic data 5 (FIG. 2 ( Based on the attenuation coefficient of each frequency band obtained from d)), attenuation correction is performed on the waveform of each band (FIG. 2 (d)). The waveform recombining means 7 recombines the waveforms of the respective bands after the attenuation correction into the waveforms of the entire band as the impulse response 8 which is attenuation-corrected for each band (see FIG. 2).
(E)), using the data as the coefficient of the convolution device 10,
By performing convolutional reproduction with the sound source 9, the natural reverberation sound 11 reflecting the reverberation time frequency characteristic can be reproduced.

[0012]

As is apparent from the above embodiments, the present invention uses the pulse train generation means to determine the pulse train which is the basis of the coefficient of the FIR filter from the measured impulse response including the characteristics of the measurement system and noise. After generating and dividing the result into time-series data of a plurality of frequency bands by the band dividing means, each band based on the attenuation coefficient of each frequency band obtained from the reverberation time frequency characteristic by the band-based attenuation correction means. Attenuation correction is performed on the waveform of No. 2, and each band waveform after the attenuation correction is synthesized again by the band-by-band waveform resynthesizing unit as a waveform of the entire band, and the data is used as a coefficient of the FIR filter to perform musical tone and convolution reproduction. As a result, it is possible to reproduce a natural reverberation sound that reflects the reverberation time frequency characteristic.

[Brief description of drawings]

FIG. 1 is a conceptual block diagram showing a reverberation sound generation method of the present invention.

FIG. 2 is a conceptual diagram of a signal waveform showing a reverberation sound generation method of the present invention.

FIG. 3 is a conceptual block diagram showing a conventional reverberation sound generation method using a measured impulse response.

FIG. 4 is a conceptual block diagram showing a conventional reverberation sound generation method using a pulse train.

[Explanation of symbols]

 1 Impulse Response Corrector 2 Measured Impulse Response 3 Pulse Train Generation Means 4 Band Dividing Means 5 Reverberation Time Frequency Characteristic Data 6 Bandwidth Attenuation Correcting Means 7 Waveform Resynthesizing Means 8 Impulse Corrected Impulse Responses 9 Sound Source 10 Convolutional Equipment 11 Reverberation

Claims (1)

[Claims] 1. A reverberation sound generation method for outputting reverberation sound by convolutionally integrating musical sound data obtained from a predetermined sound source and an actually measured impulse response, which includes measured characteristics of a measurement system and noise. Pulse train generating means for generating a pulse train that is a basis of the coefficient of the FIR filter from the impulse response, and band dividing means for dividing the pulse train into time series data of a plurality of frequency bands,
Attenuation correction means for each band that performs attenuation correction on the waveform for each band based on the attenuation coefficient of each frequency band obtained from the reverberation time frequency characteristic, and each band waveform after this attenuation correction is made again as a waveform of the entire band. A reverberation sound generation method comprising: a band-based waveform re-synthesis unit for synthesizing; and convolution-integrating the output of the band-based waveform re-synthesis unit and the musical sound data to output a reverberation sound.