Sound equipment and programs

Abstract

To provide an acoustic device and a program for reducing fatigue of listening in a listener.SOLUTION: An acoustic device 100 includes a content acquisition section 101, a sound characteristic acquisition section 102, a sound characteristic processing section 103, and a content output section 105. The content acquisition section 101 acquires audio contents. The sound characteristic acquisition section 102 acquires sound characteristic information from the audio contents. The sound characteristic processing section 103 processes the audio contents on the basis of, the sound characteristic information of the acquired audio contents and a lapsed time from the reproduction start of the audio contents. The content output section 105 outputs the processed audio contents.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an audio device and a program. [Background technology]

[0002] Listeners become fatigued when stimulated by the onset of a sound, which indicates a sudden change in volume, or by sound power, which indicates the average output volume per unit time. In order to reduce the listener's fatigue, it is necessary to carry out control to process the sound.

[0003] Patent Document 1 discloses a technique for controlling the playback of audio content so as not to disturb sleep. In this technique, one of the volume and the playback speed of the audio content is controlled according to the elapsed time from the estimated time of falling asleep. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-85928 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the volume is controlled simply based on the time that has passed since the time when the listener falls asleep, preventing the listener from falling asleep. However, Patent Document 1 cannot control the volume so that the change is not noticeable to the listener. If the listener notices the change in the sound, the listener may feel uncomfortable and become tired of listening. Therefore, there is a problem that the listener's listening fatigue when listening to the content cannot be reduced.

[0006] In consideration of such problems, the present disclosure has an object to provide an audio device and a program capable of reducing listening fatigue of a listener. [Means for solving the problem]

[0007] The audio device of the present disclosure includes a content acquisition unit that acquires audio content, a sound characteristic acquisition unit that acquires sound characteristic information from the audio content, a sound characteristic processing unit that processes the audio content based on the sound characteristic information of the acquired audio content and the elapsed time since playback of the audio content began, and a content output unit that outputs the processed audio content.

[0008] The program of the present disclosure causes a computer to execute the following processes: acquiring audio content; acquiring sound characteristic information from the audio content; processing the audio content based on the sound characteristic information of the acquired audio content and the elapsed time since playback of the audio content began; and outputting the processed audio content. Effect of the Invention

[0009] The present disclosure makes it possible to provide an audio device and a program that can reduce listening fatigue of a listener. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a configuration of an audio device according to a first embodiment. [Diagram 2] 4 is a flowchart showing the operation of the audio device according to the first embodiment. [Diagram 3] FIG. 2 is a block diagram showing the configuration of a computer according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, specific embodiments to which the present disclosure is applied will be described in detail with reference to the drawings. In each drawing, the same elements are given the same reference numerals, and for clarity of explanation, duplicate explanations will be omitted as necessary.

[0012] (First embodiment) The cause of listener fatigue is the stimuli given to the listener by the sound, such as the onset of the sound and the sound power. For example, the sharper the onset of the sound, the greater the stimulus given to the listener, and the more likely the listener will become tired of listening. Also, the greater the sound power, the greater the stimulus given to the listener, and the more likely the listener will become tired of listening.

[0013] The acoustic device 100 according to the first embodiment reduces the listener's listening fatigue by processing the sound that causes the listener to become tired of listening. However, the more the sound is processed, the more uncomfortable it feels for people, and the more likely they are to notice the processing of the sound. Therefore, it is necessary to process the sound in a way that is not noticeable to the listener.

[0014] Here, the boiled frog theory has been proposed, which says that human senses become dull when continually stimulated, in other words, people become accustomed to them. The same is true for stimuli caused by sound. For example, people may initially perceive a loud concert as loud, but after listening to the loud sound for over an hour, they no longer perceive it as loud. Also, even if an audio device is tuned to a powerful sound, after listening for several hours, people's ears will become accustomed to the sound and it will no longer sound as powerful. In other words, once people's ears have become accustomed to it, they will no longer be aware of loud or powerful sounds, and will no longer be aware that they are getting tired of listening.

[0015] Therefore, the acoustic device 100 processes sounds that cause the listener to get tired of listening, and by increasing the amount of processing over time, it takes advantage of the listener's senses that have become dull due to habituation to the sound, and processes the sound without the listener noticing, thereby reducing the listener's listening fatigue.

[0016] First, the configuration of an audio device 100 according to a first embodiment will be described with reference to Fig. 1. The audio device 100 is, for example, a device installed in a vehicle or a facility, or a device worn by a listener. The audio device 100 includes a content acquisition unit 101, a sound characteristic acquisition unit 102, a sound characteristic processing unit 103, a switching detection unit 104, and a content output unit 105.

[0017] The content acquisition unit 101 acquires audio content. Audio content is sound information such as music or other songs, conversation sounds, video sounds, etc. The content acquisition unit 101 acquires audio content from CDs / DVDs, HDDs / memory, music distribution sites and video sites on the Internet, radio / television, etc. Then, the content acquisition unit 101 supplies the acquired audio content to the sound characteristics acquisition unit 102.

[0018] The sound characteristic acquisition unit 102 acquires sound characteristic information from the audio content. The sound characteristic information includes, for example, volume, melody such as sound tempo, volume change amount per predetermined time, sound tempo change amount per predetermined time, average output volume per predetermined time, sound frequency characteristics, and sound power. The sound characteristic information is preferably information linked to the elapsed time from the start point of the audio content, and is defined, for example, for each change point of volume or melody, or for each relatively short predetermined time (for example, 1 second). Then, the sound characteristic acquisition unit 102 supplies the acquired sound characteristic information and the audio content to the sound characteristic processing unit 103.

[0019] The sound characteristic processing unit 103 processes the acquired audio content based on the sound characteristic information of the acquired audio content to reduce listening fatigue. Here, the sound characteristic processing unit 103 increases the amount of processing of the audio content (hereinafter referred to as the processing amount) as time passes from the start of playback of the audio content. Then, the sound characteristic processing unit 103 supplies the processed audio content to the content output unit 105.

[0020] The switching detection unit 104 detects switching of sound characteristic information in audio content. When the switching detection unit 104 detects switching of sound characteristic information, the sound characteristic processing unit 103 initializes the amount of processing of the audio content.

[0021] The content output unit 105 outputs the audio content processed by the sound characteristic processing unit 103. The content output unit 105 outputs the audio content to, for example, a speaker or a headphone.

[0022] Next, the operation of the acoustic device 100 according to the first embodiment will be described with reference to FIG. First, the content acquisition unit 101 acquires audio content (step S101). Then, the content acquisition unit 101 supplies the acquired audio content to the sound characteristics acquisition unit .

[0023] The sound characteristic acquisition unit 102 acquires sound characteristic information from the audio content (step S102). The sound characteristic information includes, for example, the volume, the melody such as the tempo of the sound, the amount of change in the volume per predetermined time, the amount of change in the tempo of the sound per predetermined time, the average output volume per predetermined time, the frequency characteristics of the sound, and the acoustic power.

[0024] It is preferable that the sound characteristic acquisition unit 102 includes a sound characteristic information analysis unit that analyzes sound characteristic information of the audio content before or during playback of the audio content, and acquires the analyzed sound characteristic information. In addition, in the case of audio content that has a history of past playback, the sound characteristic acquisition unit 102 may acquire the characteristic information acquired at that time by referring to a playback history database or a storage unit (not shown) that stores the sound characteristic information. In the case where the sound characteristic information is linked to the audio content as metadata or auxiliary data, the sound characteristic acquisition unit 102 may acquire the data.

[0025] Next, the sound characteristic processing unit 103 processes the acquired audio content based on the sound characteristic information of the audio content in order to reduce listening fatigue (step S103). Here, the sound characteristic processing unit 103 increases the amount of processing of the audio content as time passes from the start of playback. For example, the sound characteristic processing unit 103 makes the slope of the amount of processing per time constant. Also, the sound characteristic processing unit 103 makes the slope of the amount of processing per time in the first half of the playback time of the audio content smaller than the slope of the amount of processing per time in the second half of the playback time. Based on the acquired sound characteristic information of the audio content, the sound characteristic processing unit 103 processes the audio content to reduce the listener's listening fatigue while obtaining sound characteristics that are less likely to cause listening fatigue, such as suppressing the amount of volume change per predetermined time, suppressing the average output volume per predetermined time, and suppressing the amount of change in the tempo of the sound per predetermined time.

[0026] The sound characteristic processing unit 103 may set a maximum value of the processing amount of the audio content. When the processing amount reaches the maximum value as time passes from the start of playback of the audio content, the sound characteristic processing unit 103 maintains the processing amount of the audio content from that point onward. When the maximum value is not set, the sound characteristic processing unit 103 may maintain the processing amount of the audio content when the difference between the processing amount at the start of processing and the current processing amount becomes equal to or greater than a predetermined threshold. Furthermore, the processing amount of the audio content is initialized every time the audio content is switched, and processing for each audio content is mainly assumed, but the processing amount of the previous audio content may be maintained when the audio content is switched.

[0027] In step S103, for example, when the volume change amount per predetermined time, which is one of the acquired sound characteristic information of the audio content, is equal to or greater than a predetermined threshold, the sound characteristic processing unit 103 suppresses the volume change amount per predetermined time. Here, the sound characteristic processing unit 103 increases the suppression amount of the volume change amount per predetermined time as the time elapses from the start of playback of the audio content. For example, the sound characteristic processing unit 103 makes the slope of the suppression amount per time constant. Also, the sound characteristic processing unit 103 makes the slope of the suppression amount per time in the first half of the playback time of the audio content smaller than the slope of the suppression amount per time in the second half of the playback time. In other words, the sound characteristic processing unit 103 suppresses the rise of the sound when the rise of the sound is equal to or greater than a predetermined threshold, and gradually suppresses the rise of the sound as the time elapses from the start of playback of the audio content. By doing so, the sound characteristic processing unit 103 can reduce the listener's listening fatigue without the listener noticing, while providing sound characteristics that are less likely to cause listening fatigue.

[0028] The sound characteristic processing unit 103 may set a maximum value of the suppression amount of the volume change amount per predetermined time. When the suppression amount reaches the maximum value as time passes from the start of playback of the audio content, the sound characteristic processing unit 103 maintains the processing amount of the audio content. It is preferable that the upper limit of the suppression amount is preset to a level at which the listener does not perceive a change, or is settable by the user.

[0029] Also, in step S103, for example, when the average output volume per predetermined time, which is one of the sound characteristic information of the acquired audio content, is equal to or greater than a predetermined value, the sound characteristic processing unit 103 suppresses the average output volume per predetermined time. Here, the sound characteristic processing unit 103 increases the suppression amount of the average output volume per predetermined time as the time elapses from the start of playback of the audio content. For example, the sound characteristic processing unit 103 makes the slope of the suppression amount per time constant. Also, the sound characteristic processing unit 103 makes the slope of the suppression amount per time in the first half of the playback time of the audio content smaller than the slope of the suppression amount per time in the second half of the playback time. By doing so, the sound characteristic processing unit 103 can reduce the listener's listening fatigue without the listener noticing, while providing sound characteristics that are less likely to cause listening fatigue.

[0030] In step S103, the sound characteristic processing unit 103 suppresses the output sound volume of a predetermined frequency region when the sound volume in the predetermined frequency region is equal to or greater than a predetermined value based on the frequency characteristic, which is one of the sound characteristic information of the audio content. It is preferable to perform processing to reduce the amount of processing for sounds in a predetermined frequency region to which the listener has high sensitivity, compared to sounds in a predetermined frequency region to which the listener has low sensitivity. Specifically, the sound characteristic processing unit 103 extracts sounds in a predetermined frequency region to which the listener has high sensitivity. The predetermined frequency region to which the listener has high sensitivity is, for example, a frequency region of 3 kHz to 4 kHz when a general equal loudness curve is taken into consideration. The predetermined frequency region to which the listener has high sensitivity may be set by measuring the hearing sensitivity of a specific individual. The predetermined frequency region to which the listener has low sensitivity is, for example, a frequency region lower than 3 kHz and a frequency region higher than 4 kHz when an equal loudness curve is taken into consideration. The predetermined frequency region to which the listener has low sensitivity may be set by measuring the hearing sensitivity of a specific individual. In detail, the sound characteristic processing unit 103 has filters such as a high-pass filter (HPF), a low-pass filter (LPF), or a band-pass filter (BPF) that pass sounds in a predetermined frequency range, and extracts sounds that have passed through the filters. The sound characteristic processing unit 103 reduces the amount of suppression of the volume change per predetermined time for sounds in a predetermined frequency range to which the listener has high sensitivity, or the amount of suppression of the average output volume per predetermined time, compared to sounds in a predetermined frequency range to which the listener has low sensitivity. By doing so, the sound characteristic processing unit 103 can provide sound characteristics that are less tiring to listen to, while making the processing of the sound less noticeable to the listener.

[0031] The sound characteristic processing unit 103 may extract sounds in a predetermined frequency range to which the listener has low sensitivity. The predetermined frequency range to which the listener has high sensitivity and the predetermined frequency range to which the listener has low sensitivity can be set separately without being limited to the above-mentioned example. The sound characteristic processing unit 103 may suppress the output of sounds in the high and low ranges regardless of the listener's sensitivity. It is preferable that the sound characteristic processing unit 103 performs processing to control the amount of reduction in the high and low range sounds so that the frequency characteristics are brought closer to flat characteristics in the entire range based on the frequency characteristics, which are one of the sound characteristic information of the acquired audio content. By doing so, the sound characteristic processing unit 103 can make the sound characteristics less tiring to listen to while making the sound processing less noticeable to the listener.

[0032] Furthermore, in step S103, the switching detection unit 104 detects a switching of sound characteristic information in the audio content. For example, when the audio content is a song, the switching detection unit 104 detects a switching of the tune of the same song, a change in volume that exceeds a predetermined threshold, or a switching between different songs. Note that the switching of sound characteristic information is not limited to the above-mentioned events as long as it is an event that may damage the listener's familiarity with the audio content.

[0033] When the switching detection unit 104 detects a switch in sound characteristic information, the sound characteristic processing unit 103 initializes the amount of processing of the audio content. Specifically, when the switching detection unit 104 detects a switch in sound characteristic information, the sound characteristic processing unit 103 initializes the amount of suppression of the volume change amount per predetermined time. Also, when the switching detection unit 104 detects a switch in sound characteristic information, the sound characteristic processing unit 103 initializes the amount of suppression of the average output volume per predetermined time. By doing so, when the listener loses his / her habit due to a switch in audio content, the sound characteristic processing unit 103 resets the listener's sense by initializing the amount of processing.

[0034] As another example, the switching detection unit 104 includes a sensor that detects a change in the environment surrounding the listener. When the switching detection unit 104 detects a change in the environment surrounding the listener, the sound characteristic processing unit 103 may initialize the amount of processing of the audio content. Here, a change in the environment surrounding the listener is, for example, when the acoustic device 100 is mounted on a vehicle, the listener gets on or off the vehicle. When the acoustic device 100 is mounted on a portable device, the environment may be determined to have changed by detecting the movement or change in posture of the listener.

[0035] Then, the sound characteristic processing unit 103 supplies the processed audio content to the content output unit 105. The content output unit 105 outputs the audio content processed by the sound characteristic processing unit 103 (step S104). The content output unit 105 outputs the audio content to, for example, a speaker.

[0036] Therefore, the acoustic device 100 according to the first embodiment can process the sound without the listener noticing by taking advantage of the listener's habit of processing the sound, for example by increasing the amount of processing as time passes from the start of playback of the audio content. In addition, the acoustic device 100 can process the sound of the audio content according to sound characteristics related to the listener's listening fatigue, such as the sound onset characteristics, sound power, or sound frequency characteristics. Therefore, the acoustic device 100 can reduce the listener's listening fatigue.

[0037] For example, when the audio device 100 is installed in a vehicle, using this function while driving can reduce the listener's listening fatigue, thereby reducing the physical burden on the driver and contributing to safer driving. Furthermore, in the audio device 100, transient currents are reduced by suppressing acoustic power, etc., so power consumption is reduced and, when battery-powered, sound can be produced for a long period of time.

[0038] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present invention.

[0039] (Modification) The sound characteristic processing unit 103 of the acoustic device 100 according to the above embodiment increases the suppression amount of the volume change amount per predetermined time as time passes from the start of playback of the audio content, and accentuates the rise of the sound. In this way, the acoustic device 100 reduces the listener's listening fatigue by taking advantage of the listener's familiarity with the sound.

[0040] On the other hand, the sound characteristic processing unit 103 of the audio device 100 according to the modified example performs processing based on the acquired audio content sound characteristic information to change the sound characteristics to a powerful sound without being noticed by the listener, such as increasing the volume change amount per predetermined time, increasing the average output volume per predetermined time, and increasing the change amount of the tempo of the sound per predetermined time. For example, based on the acquired audio content sound characteristic information, if the volume change amount per predetermined time in the acquired audio content is equal to or greater than a predetermined threshold, the sound characteristic processing unit 103 increases the volume change amount per predetermined time. Then, the sound characteristic processing unit 103 increases the increase amount of the volume change amount per predetermined time as the time elapses from the start of playback of the audio content. In other words, when there is a rise in the sound, the sound characteristic processing unit 103 strengthens the rise of the sound, and strengthens the rise of the sound as the time elapses from the start of playback of the audio content. Based on the acquired audio content sound characteristic information, for example, if the volume change amount per predetermined time in the acquired audio content is equal to or less than a predetermined threshold, the sound characteristic processing unit 103 may increase the volume change amount per predetermined time.

[0041] Therefore, the acoustic device 100 according to the modified example can maintain a powerful sound without the listener noticing when the acoustic device is tuned to a powerful sound by gradually increasing the sound rise when the listener's ears become accustomed to the sound after listening to audio for a long time. Or, when the acoustic device produces a sound that is not powerful, the sound can be changed to a powerful sound without the listener noticing. By carrying out such processing, a sound that does not make the listener sleepy can be provided.

[0042] The acoustic device 100 according to the modified example may perform processing based on each of the sound characteristic information such as the volume, the melody such as the sound tempo, the amount of change in volume per predetermined time, the amount of change in the tempo of the sound per predetermined time, the average output volume per predetermined time, the frequency characteristics of the sound, the acoustic power, etc. For example, by using a technique such as increasing the average output volume per predetermined time, increasing the output volume in a predetermined frequency range, or increasing the amount of change in the tempo of the sound per predetermined time, it is possible to maintain or change the sound to have a constant impact or freshness without the listener noticing.

[0043] <Hardware configuration> Next, an example of the hardware configuration of the computer 1000 related to the audio device 100 will be described with reference to Fig. 3. In Fig. 3, the computer 1000 has a processor 1001 and a memory 1002. The processor 1001 may be, for example, a microprocessor, a micro processing unit (MPU), or a central processing unit (CPU). The processor 1001 may include a plurality of processors. The memory 1002 is configured by a combination of a volatile memory and a non-volatile memory. The memory 1002 may include a storage located away from the processor 1001. In this case, the processor 1001 may access the memory 1002 via an I / O interface not shown.

[0044] Furthermore, each device in the above-described embodiments may be configured with hardware or software, or both, and may be configured with one piece of hardware or software, or may be configured with multiple pieces of hardware or software. The functions (processing) of each device in the above-described embodiments may be realized by a computer. For example, a program for performing the method in the embodiment may be stored in memory 1002, and each function may be realized by executing the program stored in memory 1002 by processor 1001.

[0045] These programs can be stored and provided to a computer using various types of non-transitory computer readable media. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (random access memories)). The programs may also be provided to a computer by various types of temporary computer readable media. Examples of temporary computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer readable media can provide the programs to a computer via wired communication paths such as electric wires and optical fibers, or wireless communication paths. [Explanation of symbols]

[0046] 100 Sound equipment 101 Content Acquisition Department 102 Sound characteristic acquisition unit 103 Sound characteristics processing section 104 Switching detection unit 105 Content Output Unit 1000 Computers 1001 Processor 1002 Memory

Claims

1. a content acquisition unit that acquires audio content; a sound characteristic acquisition unit for acquiring sound characteristic information from the audio content; a sound characteristic processing unit that performs processing to control at least one of a volume change amount per predetermined time in the audio content and a sound tempo change amount per predetermined time in the audio content based on the acquired sound characteristic information of the audio content and an elapsed time from a start of playback of the audio content; a content output unit that outputs the processed audio content. sound equipment.

2. A content acquisition unit for acquiring audio content; a sound characteristic acquisition unit for acquiring sound characteristic information from the audio content; a sound characteristic processing unit that processes the audio content based on the acquired sound characteristic information of the audio content and an elapsed time from a start of playback of the audio content; a content output unit that outputs the processed audio content, the sound characteristic acquisition unit acquires a volume change amount per predetermined time in the audio content, The sound characteristic processing unit performs processing such that, when the amount of change in volume per predetermined time in the audio content is equal to or greater than a predetermined threshold, the amount of change in volume per predetermined time in the audio content is suppressed, and the amount of suppression of the amount of change in volume per predetermined time in the audio content is increased as time passes from the start of playback. sound equipment.

3. A content acquisition unit that acquires audio content; a sound characteristic acquisition unit for acquiring sound characteristic information from the audio content; a sound characteristic processing unit that processes the audio content based on the acquired sound characteristic information of the audio content and an elapsed time from a start of playback of the audio content; a content output unit that outputs the processed audio content, The sound characteristic processing unit processes the audio content by reducing the amount of processing for sounds in a predetermined frequency range to which the listener has a high sensitivity, compared to sounds in a predetermined frequency range to which the listener has a low sensitivity. sound equipment.

4. A content acquisition unit for acquiring audio content; a sound characteristic acquisition unit for acquiring sound characteristic information from the audio content; a change detection unit that detects, when the audio content is a piece of music, a change in the tune of the same piece of music or a change in the piece of music; a sound characteristic processing unit that processes the audio content based on the acquired sound characteristic information of the audio content and an elapsed time from a start of playback of the audio content; a content output unit that outputs the processed audio content, The sound characteristic processing unit initializes processing of the audio content when the switching detection unit detects the switching. sound equipment.

5. A process for obtaining audio content; obtaining sound characteristic information from the audio content; a process of controlling at least one of a volume change amount per predetermined time and a sound tempo change amount per predetermined time in the audio content based on the acquired sound characteristic information of the audio content and an elapsed time from the start of playback of the audio content; and outputting the processed audio content. program.

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