JP3180714U - Stereo sound generator - Google Patents

Abstract

A three-dimensional sound generation apparatus capable of producing a three-dimensional sound field using a speaker or headphones.
A sound source phase modulation means for inputting a sound signal of an environmental sound and a sound effect of a left channel and a right channel of a stereo sound source and modulating the phase of the sound signal separately for the left and right channels and the phase of the sound signal Audio signal phase inverting means for inverting the channels separately, distance setting means for setting the sound source distance condition for performing the audio signal phase modulation operation and the audio signal phase inverting operation, and left and right according to the distance setting data by the distance setting means A volume adjustment unit that performs a change process of the volume for each channel.
[Selection] Figure 2

Description

  The present invention relates to a stereophonic sound generation device, and more particularly to a stereophonic sound generation device capable of generating stereophonic sound using a two-channel speaker.

  Conventionally, a technique for generating a three-dimensional sound field and providing a three-dimensional sound that is a more realistic sound to a listener has been developed. Conventionally, in order to generate stereophonic sound, a multi-channel speaker system such as 5.1ch (channel) is used to localize a sound source outside the two speakers (possibly behind the listener). Used to generate stereophonic sound. As a technique for generating stereophonic sound using such a multi-channel speaker system, there is one described in Patent Document 1, for example. This proposes an algorithm or a computer processing program for easily localizing a sound image at a horizontal position and a vertical position in a multi-channel speaker system.

JP 2011-139263 A

  However, as described above, in order to generate stereophonic sound such as localization of a sound source outside the two speakers (possibly behind the listener), a multi-channel speaker system such as 5.1ch must be used. Therefore, there is a problem that the system configuration becomes large and the cost becomes high.

  The present invention has been made by paying attention to the above-mentioned problems, and its purpose is to produce three-dimensional sound using two speakers (standard stereo system) or standard headphones, which has not been possible in the past. The object is to provide a stereophonic sound generation system that enables field production.

  In order to achieve the above object, the present invention inputs a sound signal of stereo sound source left channel and right channel environmental sound and sound effect sound, and modulates the phase of the sound signal separately for the left and right channels; A sound signal phase inversion means for inputting a sound signal of a left sound channel, a right channel environment sound, and a sound effect of a stereo sound source, and reversing the phase of the sound signal separately for the left and right channels; and the sound signal phase modulation operation and the sound signal A stereophonic sound generating device comprising: distance setting means for setting a sound source distance condition for performing a phase inversion operation; and a volume adjusting unit for performing volume change processing separately for the left and right channels according to distance setting data by the distance setting means provide.

  By using such a three-dimensional sound generation device, a pseudo-experience sound in a two-channel stereo environment is generated by arranging a narration, a musical instrument performance, and a sound effect recorded by a binaural method on a three-dimensional environment sound and sound effect. Is possible.

  The stereophonic sound generation apparatus may include reverberation simulation means for performing reverberation simulation processing for the left and right channels of the audio signal. Further, in the phase modulation process of the audio signal, a distance / angle setting process assuming the position (distance (n) and angle (left = x, right = y)) of each sound source from the listener is performed, You may set the delay of the timing sounded by the left and right speakers from the distance and angle.

  According to the present invention, it is possible to realize a three-dimensional sound reproduction excellent in a three-dimensional effect only by hearing with a standard stereo system having only two speakers or standard headphones, It is possible to experience a 3D sound sensation as if it had entered the content world.

It is a block diagram showing schematic structure of the stereophonic sound production | generation system shown as one embodiment of this invention. It is a block diagram which shows the structure of the environmental sound source processing part of the stereophonic sound production | generation system which concerns on this Embodiment. It is a flowchart explaining the stereophonic sound production | generation process operation | movement in this Embodiment. It is the schematic explaining the phase modulation process operation | movement of the audio | voice signal in this Embodiment. It is the schematic explaining the position of the sound source by the sound which came out of the speaker in this Embodiment. It is the schematic explaining the output state of the sound in the 2 channel stereo speaker by the recording and reproduction | regeneration technique of the conventional stereophonic sound generation system.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of a stereophonic sound generating system shown as an embodiment of the present invention. In FIG. 1, the three-dimensional sound generation system is connected to an environmental sound data storage unit 1 for storing environmental sounds necessary for forming a sound field, and an environmental sound output from the environmental sound data storage unit 1. The environmental sound data processing unit 2 that processes or modulates sound data into 3D surround sound data and performs sound source localization processing, and the environmental sound data storage unit 1 and the environmental sound data processing unit 2 are arranged in a parallel relationship. Connected to the binaural recording data storage unit 3 for storing binaurally recorded audio data separately from the environmental sound data, the environmental sound data processing unit 2 and the binaural recording data storage unit 3, and output from the environmental sound data processing unit 2 The 3D surround sound data and the binaural recording data output from the binaural recording data storage unit 3 are mixed (mixed) to mix the sound data with a speaker and Or comprising a sound data mixing section 4 to be output to the headphones.

    The environmental sound data storage unit 1 is composed of a recording medium such as a hard disk, a DVD, or a digital tape. Data (voice data) is recorded (stored) in the form of digital data. Environmental sound represents sound that represents the background in audio data by broadcasting or playback, for example, wind sound, water flowing sound, or plosive sound reminiscent of a serious situation. Since the audio data is recorded in stereo, it is stored as separate data, such as left channel audio data and right channel audio data (hereinafter simply referred to as “left audio data” and “right audio data”). ing. When an audio signal is output from the environmental sound data storage unit 1 to the environmental sound data processing unit 2, the left channel audio signal, the right channel audio signal (hereinafter simply referred to as “left audio signal”, “right audio signal”). ) And so on, are output as separate signals. The binaural recording data storage unit 3 is also composed of a recording medium such as a hard disk, a DVD, or a digital tape, and a person's conversation, musical instrument performance, singing, narration, etc. recorded by the binaural recording method are recorded in the form of digital data. Yes. The audio data mixing unit 4 arranges binaural recording data in the environmental sound subjected to sound source localization to create content by one audio.

    FIG. 2 is a block diagram showing a configuration of the environmental sound data processing unit 2 in the stereophonic sound generation system. In FIG. 2, reference numeral 11 denotes a left audio signal output from the environmental sound data storage unit 1 and an audio signal (left) phase modulation unit having a function of performing phase modulation processing of the left audio signal. Reference numeral 12 denotes an audio signal. (Left) An audio signal (left) phase inversion unit that receives the left audio signal from the phase modulation unit 11 and performs phase inversion processing on the left audio signal. Reference numeral 13 denotes an audio signal (left) amplification unit that receives the left audio signal from the audio signal (left) phase inverting unit 12 and performs amplification processing on the left audio signal. Reference numeral 14 denotes an audio signal (left) amplification. An audio signal (left) attenuation unit that receives the left audio signal from the unit 13 and performs attenuation processing on the left audio signal, and 16 is an audio signal (left) in parallel with the audio signal (left) amplification unit 13. ) An audio signal (left) reverberation simulation unit which is connected to the phase inversion unit 12 and receives the left audio signal from the phase inversion unit 12 and tracks the reverberation of the left audio signal. The audio signal (left) amplifying unit 13 and the audio signal (left) attenuating unit 14 each have a function of amplifying or attenuating the left audio signal, and the left volume adjusting unit 15 is configured by both members. Reference numeral 17 denotes an audio signal (right) phase modulator having a function of performing phase modulation processing of the right audio signal, which is input from the right audio signal output from the environmental sound data storage unit 1, and 18 denotes an audio signal ( Right) An audio signal (right) phase inversion unit that receives the right audio signal from the phase modulation unit 17 and performs phase inversion processing on the right audio signal. Reference numeral 19 denotes an audio signal (right) amplification unit that receives the right audio signal from the audio signal (right) phase inversion unit 18 and performs amplification processing on the right audio signal, and 20 denotes an audio signal (right) amplification. An audio signal (right) attenuation unit that receives the right audio signal from the unit 19 and performs attenuation processing on the right audio signal, 22 is an audio signal (left) in parallel with the audio signal (left) amplification unit 19 It is an audio signal (right) reverberation simulation unit that is connected to the phase inversion unit 18 and receives the right audio signal from the phase inversion unit 18 and tracks the reverberation of the right audio signal. The audio signal (right) amplifying unit 19 and the audio signal (right) attenuating unit 20 each have a function of amplifying or attenuating the right audio signal, and a right volume adjusting unit 21 is constituted by both members.

    The environmental sound data processing unit 2 further includes a control unit 23 for controlling the operation of each functional unit and an input unit 24 for inputting instruction commands and control data to the control unit 23. A CPU is used for the control unit, which includes a memory for storing various control programs, a timer for counter operation, and a distance / angle setting means (or program) for performing sound source localization, and processing environmental sound data Controls the operation of each functional part that composes part 2. In FIG. 2, a solid line indicates a signal line indicating transmission / reception of data such as voice, and a one-dot chain line indicates a control signal line for the control unit 23 to control each functional unit. A keyboard, mouse, and other data input devices are used for the input section.

    The operation of the stereophonic sound generation system having the above configuration will be described below. FIG. 3 is a flowchart for explaining the stereophonic sound generation processing operation in the present embodiment. In order to generate stereophonic sounds, as described above, environmental sounds, sound effects, and other sounds are recorded or produced by a normal stereo recording method or a monaural (2ch) recording method (step S1). This environmental sound is stored in advance in the environmental sound data storage unit 1. In addition to environmental sounds, content such as human conversation, musical instrument performance, singing, and narration is captured by binaural recording, and these data are stored in the binaural recording data storage unit 3 in advance. Depending on the installation status of the stereophonic sound generation system, the environmental sound and the content may be sent directly from the communication line to the stereophonic sound generation system without being recorded on the recording medium.

    Next, the environmental sound data stored in the environmental sound data storage unit 1 is sent to the environmental sound data processing unit 2. Since the environmental sound data is recorded in stereo, the left audio signal and the right audio signal are sent to the environmental sound data processing unit 2 respectively. The control unit 23 inputs each audio signal to the audio signal (left) phase modulation unit 11 and the audio signal (right) phase modulation unit 17 and causes the audio signal phase modulation units 11 and 17 to perform phase modulation processing. (Step S2). FIG. 4 is a schematic diagram for explaining the phase modulation processing. In FIG. 4, reference numerals 31, 32 and 33 represent sound sources assumed at respective positions, and 34 represents a listener. In the phase modulation process, distance / angle data assuming the position (distance (n) and angle (left = x, right = y)) of each sound source from the listener is input from the input unit 24, and the control unit 23 sets the distance (n) and angle (left = x, right = y) by the built-in distance / angle setting means. The audio signal phase modulators 11 and 17 set a delay in timing of sound generation to the left and right speakers from the distance and angle, and create a three-dimensional sound field by smoothly changing the delay. As shown in the waveform graph in FIG. 4, the delay amount is tx for the left audio signal and ty for the right audio signal. The delay amount (delay time) to be set is, for example, 0 to 80 samples ( When the sampling frequency is 48 kHz, it is 0 to 1600 μsec). When the sound modulated by the above-described phase modulation processing is output from the speaker, the listener 34 can image the sound source set at each position. FIG. 5 is a schematic diagram for explaining the position of the sound source by the sound coming out of the speaker. In FIG. 5, sound sources 35, 36, 37, and 38 indicate sound sources imaged at respective positions, and are the same as (or equivalent to) the sound sources 31, 32, and 33 in FIG. 4. Reference numeral 39 denotes a left channel stereo speaker that emits sound, and 40 denotes a right channel stereo speaker. In FIG. 5, an arrow with a reference numeral 41 is an explanation of the phase modulation process described above, and when the delay of the timing of sound generation by the stereo speakers 39 and 40 is set and the delay is smoothly changed, the sound source is the sound source 36. It represents a movement (or shift) from one position to another. Similarly, the arrow 42 represents that the sound source moves from the sound source 37 to another position.

  Next, the respective audio signals (modulated audio signals) output from the audio signal phase modulation units 11 and 17 are input to the audio signal (left) phase inverting unit 12 and the audio signal (right) phase inverting unit 18. The control unit 23 causes the audio signal phase inversion units 12 and 18 to perform phase inversion processing (step S3). The audio signal phase inversion units 12 and 18 perform audio signal phase inversion processing on the delayed channel of the two stereo channels in accordance with an instruction from the control unit 23. By this audio signal phase inversion process, the sound source goes around the listener. In FIG. 15, a sound source 35 and a sound source 38 indicate sound sources that wrap around to the back side of the listener.

  Further, depending on the quality of the sound source, it is possible to emphasize more by changing the pitch slightly (several cents). Furthermore, by the signal processing operation, it is possible to edit (variably adjust) the angle of the sound source without impairing the stereo feeling of the sound source itself of the stereo file. That is, when 360-degree editing is applied to the environmental sound, an effect as if the listener's head has been rotated is obtained.

  The audio signals output from the audio signal phase inversion units 12 and 18 are an audio signal (left) amplification unit 13, an audio signal (left) reverberation simulation unit 16, an audio signal (right) amplification unit 19, and an audio signal (right). ) Each input to the reverberation simulation unit 20. The audio signal input to the audio signal (left) amplification unit 13 is further sent to the audio signal (left) attenuation unit 14. The audio signal input to the audio signal (right) amplification unit 19 is further sent to the audio signal (right) attenuation unit 20. Since the audio signal (left) amplification unit 13 and the audio signal (left) attenuation unit 14 constitute a left volume adjustment unit 15, the left of the left volume adjustment unit 15 is controlled based on the distance setting control data in the control unit 23. By performing amplification processing or attenuation processing of the audio signal, it is possible to set the position of the sound source (feeling the sound source closer when the sound is loud and feeling far away when the sound is small). Similarly, the audio signal (right) amplifying unit 19 and the audio signal (right) attenuating unit 20 constitute a right volume adjusting unit 21, and therefore, based on the distance setting control data in the control unit 23, Among them, by performing amplification processing or attenuation processing of the right audio signal, it is possible to set the position of the sound source (feeling the sound source closer when the sound is loud and feeling far away when the sound is small) (step S4).

  Further, in step S5, the control unit 23 checks the instruction data (command) from the input unit 24 and determines whether or not to change the reverberation volume for the audio signals input to the left and right audio signal reverberation simulation units 16 and 22. To do. If it is determined by this determination operation that the reverberation volume is to be changed, the control unit 23 causes the left and right audio signal reverberation simulation units 16 and 22 to perform a reverberation volume change process according to the distance setting (step S6), and then the audio. The signal is sent to the stereo speakers 39 and 40 of the left and right channels, and audio output processing is performed (step S7). If it is determined in step S5 that the reverberant volume is not changed, the control unit 23 sends the amplified or attenuated audio signal to the left and right channel stereo speakers 39 and 40 and performs audio output processing (step S7). In the above operation, the procedures of steps S2, S3, S4, and S6 may be arbitrarily changed. Further, without adopting the procedure for each process as in the flowchart shown in FIG. 3, for example, an arbitrary plurality of processing operations may be executed simultaneously and complexly by an automation control technique. As an automation control technology that realizes this simultaneous complex processing, there is software (application) such as (not shown for violation of public order and morals).

  By using the audio signal modulation technique and the audio signal inversion technique of the present invention as described above, a normal stereo or monaural audio file can be processed into three-dimensional sound.

    In the present embodiment, the position of the sound source can be set or moved as shown in FIGS. 4 and 5 by phase modulation processing. However, sound output from a two-channel stereo speaker using conventional recording and playback techniques is possible. As shown in FIG. 6, the positions of the stereo speakers 39, 40 on the left and right channels are the positions of the sound sources, and even if modulation technology is used, the sound source moves slightly around the speakers 39, 40. It was only possible to obtain a sense of listening. Therefore, in the past, a multi-channel system such as 5.1ch (channel) was required to localize the sound source outside the two speakers (possibly behind the listener). This has already been mentioned.

  According to the three-dimensional sound generation system according to the present invention, it is possible to realize a three-dimensional sound reproduction with excellent three-dimensional effect only by hearing with a standard stereo system with only two speakers or with standard headphones. The listener can experience a stereophonic sensation as if he had entered the world of the content, which has never existed before.

1 Environmental Sound Data Storage Unit 2 Environmental Sound Data Processing Unit 3 Binaural Recording Data Storage Unit 4 Audio Data Mixing Unit 11 Audio Signal (Left) Phase Modulation Unit 12 Audio Signal (Left) Phase Inversion Unit 13 Audio Signal (Left) Amplification Unit 14 Audio signal (left) attenuation unit 15 Left volume adjustment unit 16 Audio signal (left) reverberation simulation unit 17 Audio signal (right) phase modulation unit 18 Audio signal (right) phase inversion unit 19 Audio signal (right) amplification unit 20 Audio signal (Right) Attenuation unit 21 Left volume adjustment unit 22 Audio signal (Right) Reverberation simulation unit 23 Control unit 24 Input unit

Further, in step S5, the control unit 23 checks the instruction data (command) from the input unit 24 and determines whether or not to change the reverberation volume for the audio signals input to the left and right audio signal reverberation simulation units 16 and 22. To do. If it is determined by this determination operation that the reverberation volume is to be changed, the control unit 23 causes the left and right audio signal reverberation simulation units 16 and 22 to perform a reverberation volume change process according to the distance setting (step S6), and then the audio. The signal is sent to the stereo speakers 39 and 40 of the left and right channels, and audio output processing is performed (step S7). If it is determined in step S5 that the reverberant volume is not changed, the control unit 23 sends the amplified or attenuated audio signal to the left and right channel stereo speakers 39 and 40 and performs audio output processing (step S7). In the above operation, the procedures of steps S2, S3, S4, and S6 may be arbitrarily changed. Further, without adopting the procedure for each process as in the flowchart shown in FIG. 3, for example, various processing operations may be executed simultaneously and in combination by various software (applications) for realizing automation control technology. .

Claims (3)

Audio signal phase modulation means for inputting the sound signal of the left and right channels of the stereo sound source and the sound signal of the sound effect and modulating the phase of the sound signal separately for the left and right channels;
Audio signal phase inversion means for inputting the sound signal of the stereo sound source left channel, right channel environmental sound and sound effect, and inverting the phase of the sound signal separately for the left and right channels;
According to the distance setting data by the distance setting means, volume adjusting means for performing volume change processing for the left and right channels separately;
A sound source distance condition for performing the audio signal phase modulation operation and the audio signal phase inversion operation, and a control means for controlling the operation of each functional unit,
A three-dimensional sound generation device that generates simulated experience sound in a two-channel stereo environment by arranging narration, musical instrument performance, and sound effects recorded by binaural method on three-dimensionally created environmental sounds and sound effects. Furthermore, reverberation simulation means for performing reverberation simulation processing for the left and right channels separately for the audio signal,
The control unit controls to simultaneously and collectively execute operations of a plurality of functional units among the audio signal phase modulation unit, the audio signal phase inversion unit, the volume adjustment unit, and the reverberation simulation unit. The stereophonic sound generator according to claim 1.   In the phase modulation process of the audio signal, the distance / angle setting process assuming the position (distance (n) and angle (left = x, right = y)) of each sound source from the listener is performed, and the distance The stereophonic sound generating apparatus according to claim 1, wherein a delay in timing of sound generation from the left and right speakers is set from the angle and the angle.

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