JP6772889B2 - Language clarification device and loudspeaker broadcasting system - Google Patents

Description

The present invention relates to a language clarification device and a loudspeaker broadcasting system.

Various loudspeaker broadcasting systems such as disaster prevention administrative radio systems are roughly divided into a slave station that performs loudspeaker broadcasting using a loudspeaker and a master station that transmits information on the broadcast contents to the slave station. Here, for example, when the slave station is installed outdoors, it may be difficult for the user to hear the loudspeaker broadcast due to a poor external environment (noise (traffic noise, daily life noise, etc.)).

In order to deal with such an event, various studies have been conducted on the technology for clarifying loudspeaker broadcasting. For example, Patent Document 1 below discloses a technique for realizing clarification by emphasizing formants in a disaster prevention administrative radio system or the like. Further, Patent Document 2 discloses a technique of dividing a voice into phonemes, determining the necessity of emphasizing the voice, and correcting the voice using data stored in advance. Further, Patent Document 3 discloses a technique for emphasizing formants by using a formant filter bank set for each phoneme. Further, Patent Document 4 discloses a technique for emphasizing formants by using a database of filters for emphasizing formants prepared in advance.

JP-A-2015-161911 Japanese Unexamined Patent Publication No. 2008-70564 Japanese Unexamined Patent Publication No. 2004-4952 Japanese Unexamined Patent Publication No. 2003-271200

However, there is a problem that the processing load of language clarification tends to increase depending on the existing technology. For example, in the technique of Patent Document 1, formants are extracted by spectrum shaping processing based on the envelope of the spectrum, and ambient noise is recorded by thinning out the tuning that does not affect the perception of speech in noise. , The process of redistributing the thinned-out envelope energy to other important components is performed, but the processing load is high. Therefore, there is a possibility that a high-performance device is required and a processing delay occurs.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is a new and improved language clarification device capable of further reducing the processing load of language clarification. And to provide a loudspeaker broadcasting system.

In order to solve the above problem, according to a certain viewpoint of the present invention, an audio signal is divided at predetermined time intervals and a basic sound is extracted for each divided audio signal, and a formant is generated based on the characteristics of the formant. A filter processing unit that stores the filtered filter in advance, determines the application frequency of the filter based on the pitch of the basic sound and the divided audio signal, and applies the filter to the divided audio signal, and the filter. Provided is a language clarification device including a maximize processing unit that emphasizes a predetermined frequency band in an audio signal processed by the processing unit.

The filter processing unit may determine a frequency equal to or higher than the frequency of the fundamental tone as the applicable frequency.

The filter may be a comb type filter.

Further, in order to solve the above problems, according to another viewpoint of the present invention, the master station device that controls the slave station device for loudspeaker broadcasting, the slave station device that performs the loudspeaker broadcasting, and the audio of the loudspeaker broadcasting. A loudspeaker broadcasting system including a language clarification device for clarifying the above, the language clarification device is a basic sound extraction unit that divides an audio signal at predetermined time intervals and extracts a basic sound for each divided audio signal. The filter generated based on the characteristics of the formant is stored in advance, the applicable frequency of the filter is determined by the pitch of the basic sound and the divided audio signal, and the filter is applied to the divided audio signal. The master station apparatus includes a filter processing unit to be applied and a maximize processing unit that emphasizes a predetermined frequency band in the audio signal processed by the filter processing unit, and the master station apparatus transmits the audio signal to the slave station apparatus. A loudspeaker broadcasting system is provided, which includes a transmitting unit for transmitting a signal including the signal, and the slave station device includes a receiving unit for receiving the signal and a ringing control unit for controlling the loudspeaker broadcasting based on the signal. To.

As described above, according to the present invention, it is possible to further reduce the processing load of language clarification.

It is a figure which shows the structure of the loudspeaker broadcasting system which concerns on this embodiment. It is a block diagram which shows the functional structure of the language clarification apparatus which concerns on this embodiment. It is a block diagram which shows the functional structure of the processing part of the language clarification apparatus which concerns on this embodiment. It is a figure which shows an example of the transition of the frequency to which a filter is applied. It is a block diagram which shows the functional structure of the master station which concerns on this embodiment. It is a block diagram which shows the functional structure of the slave station which concerns on this embodiment. It is a sequence diagram which shows the operation of the language clarification processing by the language clarification apparatus which concerns on this embodiment. It is a block diagram which shows the hardware structure of the language clarification apparatus which concerns on this embodiment.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Background ＞
As mentioned above, various studies have been conducted on the technology for clarifying loudspeaker broadcasting. For example, Patent Document 1 discloses a technique for realizing clarification by emphasizing formants in a disaster prevention administrative radio system or the like. In Patent Document 1, voice clarification is realized mainly by two techniques. One is a technique for adapting speech to noise characteristics by spectral shaping based on the envelope of the spectrum. The other is a technology that thins out the tones that do not affect the perception of speech in noise and redistributes the energy of the thinned tones to other important components.

However, formants can be derived by extracting spectral envelopes, or tuning that does not affect the perception of speech in noise is thinned out and the energy of the decimated tuning is redistributed into the remaining tunes. The load required for the processing is large. Further, in the present technology, when adapting the sound to the noise characteristic, the noise collected in the vicinity where the broadcast is performed is used for the clarification process. However, when the broadcasting area of the loudspeaker broadcasting system is wide and the noise characteristics of each broadcasting point are different from each other, if the noise collected at only one place is used for the clarification process, the sound is produced. It cannot be fully adapted to the noise characteristics at each point. Further, if the clarification process is performed by using the noise for each broadcast point, the load required for the process becomes even larger.

The inventor of the present invention came up with the present invention in view of the above circumstances. The language clarification device according to the embodiment of the present invention creates a template of filter characteristics generated based on the characteristics of formants and stores them in advance. Then, the language clarification device divides the broadcast audio signal at predetermined time intervals, extracts the fundamental tone of the divided audio signal (the definition of the fundamental tone will be described later), and applies a filter based on the fundamental tone. To determine. As a result, the language clarification device can further reduce the processing load of clarification.

In the following, mainly, "2. Outline of loudspeaker broadcasting system according to this embodiment", "3. Functional configuration of each device", "4. Operation of language clarification device", and "5. Hardware configuration of language clarification device". The present embodiment will be described in detail in the order of ".

<2. Outline of loudspeaker broadcasting system according to this embodiment>
In the above, the background of the present invention has been described. Subsequently, an outline of the loudspeaker broadcasting system according to the embodiment of the present invention will be described.

(2-1. Configuration of loudspeaker broadcasting system)
First, the configuration of the loudspeaker broadcasting system according to the present embodiment will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of a loudspeaker broadcasting system according to the present embodiment. As shown in FIG. 1, the loudspeaker broadcasting system according to the present embodiment includes a language clarification device 100, an operation console 200, a master station 300, and a slave station 400. The master station 300 includes an antenna 310 used for wireless communication, and the slave station 400 includes an antenna 410 used for wireless communication and a loudspeaker 420 used for loudspeaker broadcasting. Each function will be described below.

(Language Clarification Device 100)
The language clarification device 100 realizes clarification of the broadcast voice by performing various processes on the voice signal used for the loudspeaker broadcast. More specifically, the language clarification device 100 performs a basic sound extraction process, a filter process, a maximize process, or the like on an audio signal input by a loudspeaker broadcaster using a microphone or the like (not shown). The processed audio signal is provided to the console 200, which will be described later. Details of the processing by the language clarification device 100 will be described later.

(Operating console 200)
The console 200 is a device for making various settings for loudspeaker broadcasting. More specifically, in the console 200, each slave station 400 to be broadcast, settings at the time of broadcasting, and the like are input by the operator of the loudspeaker broadcasting. The console 200 provides information on various settings and the audio signal provided by the language clarification device 100 to the master station 300, which will be described later.

(Master station 300)
The master station 300 transmits information used for loudspeaker broadcasting as a radio signal. More specifically, the master station 300 generates a radio signal based on the information input from the console 200, and uses the antenna 310 to transmit the radio signal to a relay station (not shown) or each slave station 400. Send to. It is assumed that there are a plurality of types of radio signals transmitted by the master station 300. For example, the master station 300 may transmit a signal instructing loudspeaker broadcasting, a signal including broadcast contents, a signal instructing the end of loudspeaker broadcasting, and the like to the slave station 400. It should be noted that these signals are merely examples, and the signals transmitted are appropriately changed depending on the type or method of loudspeaker broadcasting.

(Slave station 400)
The slave station 400 is a device that performs loudspeaker broadcasting. More specifically, the slave station 400 receives a radio signal from the master station 300 or a relay station using the antenna 410, and performs loudspeaker broadcasting using the information contained in the signal. For example, the slave station 400 determines whether or not its own station is the target of broadcasting based on the information contained in the radio signal, and if the own station is the target of broadcasting, reflects the operation setting included in the signal. In this state, loudspeaker broadcasting is performed using the loudspeaker 420. In this specification, the case where the slave station 400 is a fixed station installed on a road, a park, or the like will be described as an example, but the type of the slave station 400 is arbitrary.

(2-2. Overview of loudspeaker broadcasting system functions)
In the above, the configuration of the loudspeaker broadcasting system according to the present embodiment has been described. Subsequently, the functional outline of the loudspeaker broadcasting system according to the present embodiment will be described.

The language clarification device 100 of the loudspeaker broadcasting system according to the present embodiment first stores the filter characteristics generated based on the formant characteristics as a template. Hereinafter, in the present specification, the template of the stored filter characteristics will be described as a filter. The type of the filter is arbitrary. In this specification, it is assumed that the filter is a comb type filter. Then, when the audio signal is input by the performer of the loudspeaker broadcasting, the language clarification device 100 divides the audio signal at predetermined time intervals and extracts the basic sound by analyzing the divided audio signal. Here, the fundamental tone refers to the sound having the lowest frequency when the audio signal is represented by the synthesis of a plurality of sine waves. The predetermined time, which is the interval at which the audio signal is divided, refers to an arbitrary time, but in the present specification, for example, it is assumed that the interval at which the audio signal is divided is several tens [ms]. There is.

Then, the language clarification device 100 applies a filter stored in advance to a frequency equal to or higher than the fundamental frequency. As a result, the language clarification device 100 removes less important frequency band components such as noise from the divided audio signal while leaving important frequency band components to be emphasized as the language. Can be done.

Further, since the fundamental tone basically changes depending on the pitch, the language clarification device 100 determines the frequency to which the filter is applied according to each pitch for each divided audio signal (substantially, the fundamental tone). Synonymous with determining the frequency to which the filter is applied according to). As a result, the language clarification device 100 can appropriately cope with a voice signal whose pitch changes from moment to moment.

After that, the language clarification device 100 performs a process of amplifying a predetermined band component in the audio signal after applying the filter. Since the amplitude of the audio signal is reduced (in other words, the acoustic energy is reduced) by removing the components in the less important frequency band by applying the filter, the language clarification device 100, the reduction of the audio signal Amplification can be performed.

When the slave station 400 performs loudspeaker broadcasting using the audio signal subjected to the above processing, the loudspeaker broadcasting system according to the present embodiment has a poor external environment (noise (traffic noise, living noise, etc.), rainfall, etc.). It is possible to realize loudspeaker broadcasting that is easy for the user to hear even in a storm, storm, snow, typhoon, lightning strike, etc.). Further, the process of applying the filter based on the pitch (substantially synonymous with the process of applying the filter based on the fundamental tone) has a lower load than the process according to Patent Document 1 (the process of extracting the spectral envelope, etc.). Therefore, the loudspeaker broadcasting system according to the present embodiment can further reduce the processing load required for language clarification.

Further, although the noise spectrum is not constant, the language clarification device 100 makes it difficult to be masked by the noise spectrum component by appropriately changing the application frequency of the filter for each divided voice signal, and it becomes difficult to mask under noise. Language clarification is possible.

Further, the language clarification device 100 may be provided on the source side (operation console 200, master station 300, etc.) of the signal used for loudspeaker broadcasting, and may not be provided on the slave station 400 side. This reduces the resources required for installation, adjustment, maintenance, operation, and the like of the language clarification device 100.

<3. Functional configuration of each device>
In the above, the functional outline of the loudspeaker broadcasting system according to this embodiment has been described. Subsequently, the functional configuration of each device will be described.

(Functional configuration of language clarification device 100)
First, the functional configuration of the language clarification device 100 according to the present embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a block diagram showing a functional configuration of the language clarification device 100 according to the present embodiment. As shown in FIG. 2, the language clarification device 100 according to the present embodiment includes a switching unit 110 and a processing unit 120. Further, FIG. 3 is a block diagram showing a functional configuration of the processing unit 120 of the language clarification device 100 according to the present embodiment. As shown in FIG. 3, the processing unit 120 according to the present embodiment includes a pre-processing unit 121, a fundamental sound extraction unit 122, a filter processing unit 123, and a maximize processing unit 124. Each functional configuration will be described below.

(Switching unit 110)
The switching unit 110 switches whether or not to perform processing by the language clarification device 100 on the voice signal (hereinafter, referred to as "language clarification processing" for convenience). More specifically, when the switching unit 110 receives the voice signal and the switching control signal from the external device, the switching unit 110 analyzes the switching control signal and determines that the language clarification processing is required. The voice signals are sequentially provided to the processing unit 120, and when it is determined that the language clarification processing is not required, the voice signals are sequentially provided to the operation console 200 without going through the language clarification device 100. The switching unit 110 does not receive the switching control signal from the external device, but the operator of the loudspeaker broadcast operates an input unit (not shown, buttons, switches, touch panel, etc.) provided in the language clarification device 100. The switching unit 110 may generate the switching control signal by itself.

(Processing unit 120)
The processing unit 120 performs language clarification processing on the voice signal. As described above, the processing unit 120 includes a pre-processing unit 121, a fundamental tone extraction unit 122, a filter processing unit 123, and a maximize processing unit 124. Hereinafter, each functional configuration of the processing unit 120 will be described.

(Pretreatment unit 121)
The pre-processing unit 121 performs various processing on the voice signal to facilitate the processing in the post-process. The various processes include arbitrary signal processing. For example, the preprocessing unit 121 performs amplification processing, smoothing processing, shaping processing, or the like on the audio signal. The pre-processing unit 121 provides the audio signals that have undergone various processing to the fundamental tone extraction unit 122 and the filter processing unit 123, which will be described later. The preprocessing unit 121 may receive feedback from the fundamental tone extraction unit 122 or the filter processing unit 123 to re-execute various processes, or may change the parameters used for the various processes.

(Fundamental tone extraction unit 122)
The fundamental tone extraction unit 122 extracts the fundamental tone of the voice signal. More specifically, the fundamental tone extraction unit 122 extracts the fundamental tone for each divided audio signal by dividing the audio signal subjected to various processing by the preprocessing unit 121 and analyzing the signal. Then, the fundamental tone extraction unit 122 provides information on the fundamental tone for each divided audio signal to the filter processing unit 123, which will be described later, as a control signal.

(Filter processing unit 123)
The filter processing unit 123 performs a process of applying a filter to the voice signal (hereinafter, referred to as a “filter process” for convenience). More specifically, the filter processing unit 123 stores the filter generated based on the formant characteristics in advance, and when the preprocessing unit 121 provides the audio signal, the filter processing unit 123 is provided by the fundamental tone extraction unit 122. A filter is applied to frequencies above the fundamental frequency based on the control signal.

Here, the filtering process will be described with reference to FIG. FIG. 4 is a diagram showing an example of the transition of the frequency to which the filter is applied. First, the fundamental tone extraction unit 122 analyzes the audio signal at time point 1 (for example, when the input of the audio signal is started) and extracts the fundamental tone. Then, as shown in FIG. 4A, the filter processing unit 123 applies the filter to the frequency of the fundamental tone F0 or higher. Then, the fundamental tone extraction unit 122 analyzes the audio signal at the time point 2 divided immediately after the time point 1. Since the pitch of the audio signal at time point 1 and the pitch of the audio signal at time point 2 are different from each other, the fundamental tone at time point 1 and the fundamental tone at time point 2 are different from each other. The fundamental tone extraction unit 122 extracts the fundamental tone of the audio signal at time point 2, and as shown in FIG. 4B, the filter processing unit 123 applies a filter to a frequency equal to or higher than the fundamental tone frequency F0 + α. After that, the fundamental tone extraction unit 122 and the filter processing unit 123 perform the same processing on the audio signal at the time point 3, thereby filtering the frequency of the fundamental tone frequency F0-β or higher as shown in FIG. 4C. Apply.

In this way, the filter processing unit 123 can appropriately respond to an audio signal whose pitch changes from moment to moment by changing the frequency to which the filter is applied according to the fundamental tone. it can. The filter processing unit 123 provides the filtered audio signal to the maximize processing unit 124.

(Maximize processing unit 124)
The maximize processing unit 124 performs amplification processing (hereinafter, referred to as “maximization processing” for convenience) on the voice signal. More specifically, since the amplitude of the voice signal is reduced by the filter processing in the previous stage, the maximize processing unit 124 performs the maximize processing for amplifying the component of the frequency band important for voice recognition by the amount of the reduction.

(Functional configuration of master station 300)
In the above, the functional configuration of the language clarification device 100 has been described. Subsequently, the functional configuration of the master station 300 will be described with reference to FIG. FIG. 5 is a block diagram showing a functional configuration of the master station 300 according to the present embodiment.

As shown in FIG. 5, the master station 300 includes a wired communication unit 320, a generation unit 330, a wireless communication unit 340, and a control unit 350. Further, the wireless communication unit 340 includes an antenna 310. Each functional configuration will be described below.

(Wired communication unit 320)
The wired communication unit 320 is an interface to a wired network that receives information used for loudspeaker broadcasting from the console 200. More specifically, when a loudspeaker broadcaster inputs each slave station 400 to be broadcast, settings at the time of broadcasting, etc. using the console 200, the wired communication unit 320 receives such information. Is received from the operation console 200 and provided to the generation unit 330, which will be described later.

(Generator 330)
The generation unit 330 generates various signals based on the information received by the wired communication unit 320. More specifically, the generation unit 330 generates a signal for instructing loudspeaker broadcasting, a signal including broadcast contents, a signal for instructing the end of loudspeaker broadcasting, and the like, and transmits these signals to the wireless communication unit 340 described later. provide.

(Wireless communication unit 340)
The wireless communication unit 340 functions as a transmission unit that transmits a wireless signal to the slave station 400. Specifically, the wireless communication unit 340 converts various signals provided by the generation unit 330 into wireless signals by the antenna 310 and transmits the signals.

(Control unit 350)
The control unit 350 comprehensively controls various processes in the master station 300. For example, when various information used for loudspeaker broadcasting is provided from the console 200, the control unit 350 controls each functional configuration to transmit a signal including the information used for loudspeaker broadcasting to the slave station 400. ..

(Functional configuration of slave station 400)
In the above, the functional configuration of the master station 300 has been described. Subsequently, the functional configuration of the slave station 400 will be described with reference to FIG. FIG. 6 is a block diagram showing a functional configuration of the slave station 400 according to the present embodiment.

As shown in FIG. 6, the slave station 400 includes a wireless communication unit 430, a control unit 440, and a ringing control unit 450. Further, the wireless communication unit 430 includes an antenna 410, and the ringing control unit 450 includes a loudspeaker 420. Each functional configuration will be described below.

(Wireless communication unit 430)
The wireless communication unit 430 functions as a receiving unit that receives a wireless signal from the master station 300. More specifically, the radio communication unit 430 receives the radio signal transmitted from the master station 300 by the antenna 410, demodulates or decodes the signal, and obtains information used for loudspeaker broadcasting. get. The wireless communication unit 430 provides the information to the control unit 440, which will be described later.

(Control unit 440)
The control unit 440 comprehensively controls various processes in the slave station 400. For example, the control unit 440 realizes loudspeaker broadcasting by providing the information provided by the wireless communication unit 430 to the ringing control unit 450. The control unit 440 performs various processes on the information provided by the wireless communication unit 430, and generates a signal for controlling the ringing control unit 450 based on the information to generate the ringing control unit 450. You may control it.

(Ring control unit 450)
The ringing control unit 450 controls the loudspeaker broadcasting. More specifically, the ringing control unit 450 realizes loudspeaker broadcasting by controlling the loudspeaker 420 based on the information provided by the control unit 440.

<4. Operation of language clarification device>
In the above, the functional configuration of each device has been described. Subsequently, the operation of the language clarification process will be described with reference to FIG. 7. FIG. 7 is a sequence diagram showing the operation of the language clarification process by the language clarification device 100 according to the present embodiment.

In step S1000, the preprocessing unit 121 performs various processes (amplification process, smoothing process, shaping process, etc.) on the voice signals sequentially input. In step S1004, the pre-processing unit 121 sequentially provides the voice signals subjected to various processing to the fundamental sound extraction unit 122, and in step S1008, the pre-processing unit 121 sequentially provides the voice signals to the filter processing unit 123. In step S1012, the fundamental tone extraction unit 122 divides the audio signal at predetermined time intervals, and in step S1016, the fundamental tone extraction unit 122 extracts the fundamental tone for each divided audio signal. In step S1020, the fundamental tone extraction unit 122 generates a control signal including information on the fundamental tone for each divided audio signal, and provides the signal to the filter processing unit 123.

In step S1024, the filter processing unit 123 performs filter processing on the divided voice signal by applying a filter to a frequency equal to or higher than the fundamental frequency based on the control signal. In step S1028, the filter processing unit 123 provides the maximize processing unit 124 with the audio signal after the filter processing. In step S1032, the maximizing processing unit 124 performs the maximizing processing for amplifying a predetermined band component with respect to the voice signal. After that, the maximize processing unit 124 provides the operation console 200 with the audio signal after the maximize process is performed.

The above is the operation of the language clarification process by the language clarification device 100. The operation shown in FIG. 7 is continuously performed as long as an audio signal is input. Further, the operations shown in FIG. 7 may be performed in parallel. For example, preprocessing by the preprocessing unit 121 (step S1000), division of the voice signal by the fundamental tone extraction unit 122 (step S1012) or extraction processing of the fundamental tone (step S1016), filtering processing by the filtering unit 123 (step S1024), or The maximizing process (step S1032) by the maximizing processing unit 124 may be performed in parallel. As a result, the audio signals input to the language clarification device 100 can be smoothly processed in sequence, so that loudspeaker broadcasting can be performed without delay or interruption of audio. Since the operation described above is just an example, it can be performed as appropriate.

<5. Hardware configuration of language clarification device>
The operation of the language clarification process has been described above. Subsequently, the hardware configuration of the language clarification device 100 according to the present embodiment will be described with reference to FIG.

FIG. 8 is a block diagram showing a hardware configuration of the language clarification device 100 according to the present embodiment, and the language clarification device 100 is embodied by the information processing device 900 shown in FIG. The information processing device 900 includes a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 902, a RAM (Random Access Memory) 903, a host bus 904, a bridge 905, an external bus 906, and an interface 907. , An input device 908, an output device 909, a storage device 910, and a communication device 911.

The CPU 901 functions as an arithmetic processing device and a control device, and controls the overall operation in the information processing device 900 according to various programs. Further, the CPU 901 may be a microprocessor. The ROM 902 stores programs, calculation parameters, and the like used by the CPU 901. The RAM 903 temporarily stores a program used in the execution of the CPU 901, parameters that change appropriately in the execution, and the like. These are connected to each other by a host bus 904 composed of a CPU bus or the like. The switching unit 110, the processing unit 120, the preprocessing unit 121, the fundamental tone extraction unit 122, the filter processing unit 123, or the maximize processing unit 124 of the language clarification device 100 can be embodied by the CPU 901.

The host bus 904 is connected to an external bus 906 such as a PCI (Peripheral Component Interconnect / Interface) bus via a bridge 905. It is not always necessary to separately configure the host bus 904, the bridge 905, and the external bus 906, and these functions may be implemented in one bus.

The input device 908 includes input means for the user to input information such as a mouse, keyboard, touch panel, buttons, microphone, switch, and lever, and an input control circuit that generates an input signal based on the input by the user and outputs the input signal to the CPU 901. It is composed of etc. A user who operates the information processing device 900 can input various data to the information processing device 900 and instruct a processing operation by operating the input device 908.

The output device 909 includes, for example, a CRT (Cathode Ray Tube) display device, a liquid crystal display (LCD) device, an OLED (Organic Light Emitting Node) device, a display device such as a lamp, and an audio output device such as a speaker.

The storage device 910 is a device for storing data. The storage device 910 may include a storage medium, a recording device that records data on the storage medium, a reading device that reads data from the storage medium, a deletion device that deletes the data recorded on the storage medium, and the like. The storage device 910 is composed of, for example, a flash memory. The storage device 910 may drive a flash memory and store a program executed by the CPU 901 and various data.

The communication device 911 is, for example, a communication interface composed of a communication device or the like for connecting to a network. Further, the communication device 911 may be a wireless LAN (Local Area Network) compatible communication device or a wire communication device that performs wired communication.

<6. Conclusion>
As described above, the language clarification device 100 according to the present embodiment divides the audio signal at predetermined time intervals, extracts the fundamental tone for each divided audio signal, and with respect to a frequency equal to or higher than the frequency of the fundamental tone. , Apply the filter stored in advance. As a result, the language clarification device 100 removes less important frequency band components such as noise from each divided audio signal while leaving important frequency band components to be emphasized as a language. Therefore, it is possible to appropriately respond to an audio signal whose pitch changes from moment to moment.

Although the noise spectrum is not constant, the language clarification device 100 makes it difficult to be masked by the noise spectrum component by appropriately changing the application frequency of the filter for each divided voice signal, and under noise. Language clarification is possible.

Then, the slave station 400 performs loudspeaker broadcasting using the audio signal after the language clarification process, so that the loudspeaker broadcasting system according to the present embodiment has a poor external environment (noise (traffic noise, living noise, etc.), rainfall, etc.). , Storm rain, storm snow, typhoon, lightning strike, etc.), it is possible to realize loudspeaker broadcasting that is easy for the user to hear. Further, since the process of applying the filter based on the pitch (substantially synonymous with the process of applying the filter based on the fundamental tone) has a lower load than the process according to Patent Document 1, the loudspeaker broadcasting according to the present embodiment. The system can further reduce the processing load required for language clarification.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that anyone with ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, the functional configuration of each device may be appropriately provided in the external device. For example, each of the switching unit 110, the preprocessing unit 121, the fundamental tone extraction unit 122, the filter processing unit 123, and the maximizing processing unit 124 of the language clarification device 100 may be provided in an external device as appropriate.

In addition, the positional relationship of each device or the mode of cooperation can be changed as appropriate. For example, the language clarification device 100 may be provided on the slave station 400 side instead of the source side (operator console 200, master station 300, etc.) of the loudspeaker broadcast signal. As a result, the practitioner of loudspeaker broadcasting can change the parameters of language clarification processing, the type of filter, etc. for each slave station 400, so that the noise generation situation in the place where each slave station 400 is installed can be determined. Corresponding language clarification can be realized. Further, the function of the language clarification device 100 may be possessed by any of the operation console 200, the master station 300, and the slave station 400.

Further, the communication method described above may be changed as appropriate. For example, the master station 300 and the slave station 400 may perform wired communication instead of wireless communication, and the language clarification device 100, the console 200, or the master station 300 may perform wireless communication instead of wired communication. ..

100 Language clarification device 110 Switching unit 120 Processing unit 121 Preprocessing unit 122 Basic sound extraction unit 123 Filter processing unit 124 Maximizing processing unit 200 Operation console 300 Master station 310 Antenna 320 Wired communication unit 330 Generation unit 340 Wireless communication unit 350 Control unit 400 Slave station 410 Antenna 420 Loudspeaker 430 Wireless communication unit 440 Control unit 450 Ring control unit

Claims (4)

A fundamental tone extraction unit that divides the audio signal at predetermined time intervals and extracts the fundamental tone for each divided audio signal.
A filter generated based on the characteristics of the formant is stored in advance, the applicable frequency of the filter is determined by the pitch of the fundamental tone and the divided audio signal, and the filter is applied to the divided audio signal. Filter processing unit and
A maximize processing unit that emphasizes a predetermined frequency band in the audio signal processed by the filtering unit is provided.
Language clarification device. The filter processing unit determines a frequency equal to or higher than the frequency of the fundamental tone as the applicable frequency.
The language clarification device according to claim 1. The filter is a comb-shaped filter,
The language clarification device according to any one of claims 1 or 2. A loudspeaker broadcasting system including a master station device for controlling a slave station device for loudspeaker broadcasting, the slave station device for performing the loudspeaker broadcast, and a language clarifying device for clarifying the sound of the loudspeaker broadcast.
The language clarification device is
A fundamental tone extraction unit that divides the audio signal at predetermined time intervals and extracts the fundamental tone for each divided audio signal.
A filter generated based on the characteristics of the formant is stored in advance, the applicable frequency of the filter is determined by the pitch of the fundamental tone and the divided audio signal, and the filter is applied to the divided audio signal. Filter processing unit and
A maximize processing unit that emphasizes a predetermined frequency band in the audio signal processed by the filtering unit is provided.
The master station device is
A transmission unit for transmitting a signal including the audio signal to the slave station device is provided.
The slave station device
A receiver that receives the signal and
A ringing control unit that controls the loudspeaker broadcast based on the signal.
Loudspeaker broadcasting system.

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