Acoustic device, information collection system, information collection method, and program

Abstract

An acoustic device according to the present invention comprises an open-ear housing, a speaker, one or more microphones, a measurement unit, an estimation unit, and a correction unit. The speaker is disposed on the concha cavity side of the housing. The one or more microphones are disposed in the housing. The measurement unit collects sound based on a predetermined signal by the microphone. The estimation unit estimates HpTF on the basis of a sound signal collected by the measurement unit. The correction unit uses the estimated HpTF to correct an input signal to the acoustic device. An information collection system according to the present invention further comprises an information collection device. The information collection device includes an earplug microphone, a determination unit, and a recording unit. The determination unit obtains HpTF from a sound signal obtained by collecting the sound based on the predetermined signal by the earplug microphone.

Description

Acoustic device, information collection system, information collection method, and program

[0001] The present invention relates to an open-ear type acoustic device, an information collection system, an information collection method, and a program for an open-ear type acoustic device.

[0002] The HpTF (Headphone Transfer Function) is known as a characteristic that is transformed before a reproduced sound source is heard. The HpTF is a characteristic from the input to the earphone to the entrance of the ear canal, and is a characteristic that combines the mechanical, electrical, and acoustic characteristics of the earphone with characteristics based on the earphone's wearing position and pinna shape. Since there are individual differences in characteristics based on the earphone's wearing position and pinna shape, there are also individual differences in the HpTF. Non-Patent Document 1 is known regarding an individual analysis of transfer characteristics based on pinna shape in open-ear earphones.

[0003] Yuki Watanabe, Daisuke Chiba, Shihori Kozuka, Tatsuya Kako, Hiroaki Ito, Kenichi Noguchi, "Individual Analysis of Transfer Characteristics Based on Pinna Shape for Open-Ear Earphones," Proceedings of the Acoustical Society of Japan, September 2023.

[0004] Due to the presence of HpTF, the position of the virtual sound image shifts from the position of the playback sound source. To correct this shift, earphones can be equipped with a filter that corrects the HpTF. While HpTF can be measured by placing a microphone at the entrance of the ear canal, this measurement is time-consuming and difficult for users of audio devices to measure themselves. The present invention aims to provide users of audio devices (earphones) with an audio device that easily corrects the HpTF.

[0005] The acoustic device of the present invention comprises an open-ear housing, a speaker, one or more microphones, a measurement unit, an estimation unit, and a correction unit. The speaker is disposed on the cavity of the concha side of the housing. The one or more microphones are disposed in the housing. The measurement unit collects sound based on a predetermined signal with the microphone. The estimation unit estimates an HpTF based on the sound signal collected by the measurement unit. The correction unit corrects an input signal to the acoustic device using the estimated HpTF.

[0006] The information collection system of the present invention includes an acoustic device and an information collection device. The acoustic device includes an open-ear housing, a speaker, one or more microphones, and a measurement unit. The speaker is located on the cavity of the concha side of the housing. The one or more microphones are located in the housing. The measurement unit uses the microphone to collect sound based on a predetermined signal. The information collection device includes an earplug microphone, a determination unit, and a recording unit. The determination unit determines the HpTF from the sound signal collected by the earplug microphone that is based on the predetermined signal. The recording unit records information based on the sound signal collected by the microphone for the same ear in association with the HpTF calculated by the determination unit.

[0007] According to the acoustic device of the present invention, the HpTF is estimated and corrected based on the sound signal picked up by the measuring unit using the speaker and microphone of the acoustic device, so that an acoustic device that easily corrects the HpTF can be provided to users of the acoustic device (earphones).

[0008] FIG. 1 shows an example of the functional configuration of an acoustic device and an information gathering system of the present invention. FIG. 2 shows the appearance of an acoustic device of the present invention worn on the ear. FIG. 3 shows an example of the processing flow of an information gathering method of the present invention. FIG. 4 shows the results of measuring HpTFs with the earplug microphone 210 in both ears of three people with small ears without the inverting phase unit 130. FIG. 5 shows the results of measuring HMTFs with the inner microphone 140 in both ears of three people with small ears without the inverting phase unit 130 and without the earplug microphone 210. FIG. 6 shows the results of measuring HMTFs with the outer microphone 150 in both ears of three people with small ears without the inverting phase unit 130 and without the earplug microphone 210. FIG. 7 shows the results of measuring HpTFs with the earplug microphone 210 in both ears of three people with small ears with the inverting phase unit 130. 1 shows the results of measuring the HMTFs of the ears of three people with small ears using the inner microphone 140 with the inverting phase unit 130 and without the earplug microphone 210. FIG. 2 shows the results of measuring the HMTFs of the ears of three people with small ears using the outer microphone 150 with the inverting phase unit 130 and without the earplug microphone 210. FIG. 3 shows the results of measuring the HpTFs of the ears of three people with large ears using the earplug microphone 210 without the inverting phase unit 130. FIG. 4 shows the results of measuring the HMTFs of the ears of three people with large ears using the inner microphone 140 without the inverting phase unit 130 and without the earplug microphone 210. FIG. 5 shows the results of measuring the HMTFs of the ears of three people with large ears using the outer microphone 150 without the inverting phase unit 130 and without the earplug microphone 210. 1 shows the results of measuring HpTFs at both ears of three people with larger ears with the inverted phase section 130 and the earplug microphone 210. FIG. 2 shows the results of measuring HMTFs at both ears of three people with larger ears with the inverted phase section 130 and the inner microphone 140 without the earplug microphone 210. FIG. 3 shows the results of measuring HMTFs at both ears of three people with larger ears with the inverted phase section 130 and the outer microphone 150 without the earplug microphone 210. FIG. 4 shows the correlation between HMTFs and HpTFs collected by the inner microphone 140 without the inverted phase section 130. FIG. 5 shows the correlation between HMTFs and HpTFs collected by the outer microphone 150 without the inverted phase section 130. FIG. 6 shows the correlation between HMTFs and HpTFs collected by the inner microphone 140 with the inverted phase section 130. 10 is a diagram showing the correlation between the HMTF and HpTF of a sound picked up by the outer microphone 150 in the presence of the anti-phase section 130. FIG. 11 is a diagram showing an example of the functional configuration of a computer.

[0009] Hereinafter, embodiments of the present invention will be described in detail. Components having the same functions are given the same numbers, and duplicated explanations will be omitted.

[0010] <Acoustic Device> Fig. 1 shows an example of the functional configuration of an acoustic device and an information collection system of the present invention, and Fig. 2 shows an acoustic device of the present invention worn on an ear. Fig. 3 shows an example of the processing flow of an information collection method of the present invention. The acoustic device 100 of the present invention comprises an open-ear type housing 110, a speaker 120, one or more microphones 145, a measurement unit 160, an estimation unit 170, a correction unit 180, and an attachment unit 190. The speaker 120 is disposed on the cavity of the concha 910 side of the housing 110. The one or more microphones 145 are disposed in the housing 110. The acoustic device 100 is attached to the auricle 930 by the attachment unit 190. Note that while the attachment unit 190 shown in Fig. 2 is of a type that attaches the acoustic device 100 to the auricle 930, an attachment unit in the shape of glasses may also be used.

[0011] The microphone 145 may include an inner microphone 140 arranged on the cavity of the concha 910 side of the housing 110, and an outer microphone 150 arranged on the opposite side of the housing from the cavity of the concha 910. In addition, if the outer microphone 150 is included, an anti-phase unit 130 that emits sound of an opposite phase to the speaker 120 arranged on a side other than the cavity of the concha 910 side of the housing 110 may also be provided. The anti-phase unit 130 may be configured by forming a hole on the opposite side of the cavity of the concha 910 or on the side of the housing 110, and utilizing the back pressure of the speaker 120.

[0012] The measurement unit 160 uses the microphone 145 to collect sound based on a predetermined signal. The "predetermined signal" is, for example, a sweep signal. The signal may be a signal whose frequency gradually changes over a predetermined frequency range (for example, 20 Hz to 20 kHz). The frequency characteristics of the collected sound signal are referred to as the HMTF (Headphone to Microphone Transfer Function). If an internal microphone 140 and an external microphone 150 are present, sound is collected by both. The frequency characteristics of the sound signal collected by the internal microphone 140 are also HMTF, and the frequency characteristics of the sound signal collected by the external microphone 150 are also HMTF. A "sound signal" is a signal obtained by converting sound into an electrical signal, and includes signals that have undergone conversion processing such as digitization.

[0013] The estimation unit 170 estimates the HpTF based on the sound signal collected by the measurement unit. The correction unit 180 corrects the input signal to the acoustic device 100 using the estimated HpTF. The estimation unit 170 can use several estimation methods. In the first estimation method, the estimation unit 170 estimates the HpTF by selecting one HpTF from multiple predetermined HpTFs based on information correlated with the HpTF contained in the sound signal. Based on the experimental results described below, there are frequency bands in which the HMTF and HpTF are correlated. By selecting one HpTF from multiple predetermined HpTFs using the characteristics of the correlated frequency bands, it is possible to select an HpTF that is close to the HpTF experienced when the user is wearing the device. By setting approximately 3 to 5 HpTFs as the multiple predetermined HpTFs, differences in HpTF due to individual differences in the wearing position of the acoustic device 100 or the size of the auricle can be significantly corrected. The second estimation method is a method in which the estimation unit 170 uses a model that outputs an HpTF when information based on a sound signal is input. A setting method for selecting one HpTF from a plurality of predetermined HpTFs and a method for generating the model will be described later.

[0014] According to the acoustic device 100, the HpTF is estimated and corrected based on a sound signal collected by the measurement unit 160 using the speaker 120 and microphone 145 of the acoustic device, thereby providing the user with an acoustic device that can easily correct the HpTF. For example, by selecting one HpTF from a plurality of predetermined HpTFs based on information about a frequency band that is correlated with the HpTF contained in the sound signal, it is possible to select an HpTF that is close to the HpTF when the user is wearing the acoustic device. This allows the input signal to the acoustic device 100 to be appropriately corrected. Furthermore, with the method using a model, the HpTF can be corrected in detail, which is thought to enable correction that accommodates differences in the position when the same person wears the acoustic device 100.

[0015] <Information Collection System> The information collection system 20 has an acoustic device 101 and an information collection device 200. The acoustic device 101 of the information collection system 20 includes an open-ear housing 110, a speaker 120, one or more microphones 145, a measurement unit 160, and an attachment unit 190. The acoustic device 101 needs to have the same configuration as the acoustic device 100 that affects acoustic characteristics, such as shape, but does not need to include the estimation unit 170 and the correction unit 180. However, the acoustic device 100 may be used to actually reproduce acoustic signals.

[0016] Information collection device 200 includes earplug microphone 210, determination unit 220, and recording unit 290. Determination unit 220 determines an HpTF from a sound signal obtained by earplug microphone 210 collecting a sound based on a predetermined signal. Recording unit 290 associates information based on a sound signal collected by microphone 145 for the same ear with the HpTF determined by determination unit 220 and records the associated information. Information collection device 200 may also include model generation unit 230. Model generation unit 230 generates a model that outputs an HpTF when information based on the sound signal is input, from the HpTF associated with the information based on the sound signal collected by microphone 145 and recorded in recording unit 290.

[0017] An information collection method using the information collection system 20 will be described with reference to Figure 3. The information collection method includes an HMTF measurement step S160, an HpTF measurement step S210, a determination step S220, and a recording step S290. The information collection method also includes an HpTF association step S230 when selecting one HpTF from a plurality of predetermined HpTFs. The information collection method also includes a model generation step S231 when generating a model.

[0018] In the HMTF measurement step S160, a person attaches the housing 110 to their ear without wearing the earplug microphone 210, and the microphone 145 collects sound based on a predetermined signal. The microphone 145 may include an inner microphone 140 and an outer microphone 150. In the HpTF measurement step S210, a person attaches the housing 110 to their ear with the earplug microphone 210 attached to the ear canal 920, and the earplug microphone 210 collects sound based on a predetermined signal. In the determination step S220, the determination unit 220 of the information collection device 200 calculates the HpTF based on the sound signal collected by the earplug microphone 210. Note that the HMTF measurement step S160 may be performed after the HpTF measurement step S210 and the determination step S220 have been performed.

[0019] In recording step S290, the recording unit 290 of the information collection device 200 records information based on sound signals collected by the microphone 145 for the same ear, in association with the HpTF determined by the determination unit 220. By repeating steps S160 to S290, the recording unit 290 records information based on sound signals collected by the microphone 145 for various ears, in association with the HpTF for each ear. This repetitive process is repeated until a sufficient amount of information has been recorded (S291).

[0020] In the HpTF association step S230, information correlated with the HpTF contained in the sound signal is associated with one of a plurality of predetermined HpTFs based on the HpTF determined by the determination unit 220. The HpTF association step S230 may be performed manually. When generating a model, in the model generation step S231, the model generation unit 230 may generate a model that outputs an HpTF when information based on the sound signal is input, from the HpTFs associated with information based on the sound signal picked up by the microphone 145 and recorded in the recording unit 290.

[0021] <Experimental Results> The following are the results of an experiment that confirmed that there are frequency bands in which there is a correlation between HMTF and HpTF. The acoustic device 100 used in the experiment included an open-ear housing 110, a speaker 120, an internal microphone 140, an external microphone 150, a measurement unit 160, and an attachment unit 190, as well as an anti-phase unit 130. An earplug microphone 210 was also used. Note that measurements using the internal microphone 140 and the external microphone 150 were made assuming that the user was wearing the acoustic device 100. When the user used the acoustic device 100, the earplug microphone 210 was not worn. Because the acoustic effect of the ear canal 920 changes depending on whether or not the earplug microphone 210 is present, measurements were made without the earplug microphone 210 (without the earplug microphone).

[0022] FIG. 4A shows the results of measuring the HpTFs of three people with small ears using the earplug microphone 210 without the anti-phase unit 130. In other words, the results are for six small ears. Hereinafter, when "both ears" is used, the left and right ears are treated as separate ears. The acoustic device 100 was attached to each ear, measured, and then removed three times. Therefore, 18 measurement results are shown. As in the following, the 18 measurement results are shown overlappingly in FIGS. 4A to 7C. FIG. 4B shows the results of measuring the HMTFs of three people with small ears using the inner microphone 140 without the anti-phase unit 130 and the earplug microphone 210. FIG. 4C shows the results of measuring the HMTFs of three people with small ears using the outer microphone 150 without the anti-phase unit 130 and the earplug microphone 210. The horizontal axis represents frequency, and the vertical axis represents power spectrum.

[0023] Figure 5A shows the results of measuring the HpTF in both ears of three people with small ears with the anti-phase unit 130 and the earplug microphone 210. Figure 5B shows the results of measuring the HMTF in both ears of three people with small ears with the anti-phase unit 130 and the inner microphone 140 without the earplug microphone 210. Figure 5C shows the results of measuring the HMTF in both ears of three people with small ears with the anti-phase unit 130 and the outer microphone 150 without the earplug microphone 210. The horizontal axis represents frequency, and the vertical axis represents power spectrum.

[0024] Fig. 6A shows the results of measuring the HpTF in both ears of three people with larger ears using the earplug microphone 210 without the anti-phase unit 130. Fig. 6B shows the results of measuring the HMTF in both ears of three people with larger ears using the inner microphone 140 without the anti-phase unit 130 and the earplug microphone 210. Fig. 6C shows the results of measuring the HMTF in both ears of three people with larger ears using the outer microphone 150 without the anti-phase unit 130 and the earplug microphone 210. The horizontal axis represents frequency, and the vertical axis represents power spectrum.

[0025] Fig. 7A shows the results of measuring the HpTF in both ears of three people with larger ears with the anti-phase unit 130 and the earplug microphone 210. Fig. 7B shows the results of measuring the HMTF in both ears of three people with larger ears with the anti-phase unit 130 and the inner microphone 140 without the earplug microphone 210. Fig. 7C shows the results of measuring the HMTF in both ears of three people with larger ears with the anti-phase unit 130 and the outer microphone 150 without the earplug microphone 210. The horizontal axis represents frequency, and the vertical axis represents power spectrum.

[0026] From the HpTF characteristics shown in Figures 4A, 5A, 6A, and 7A, below 5 kHz, the HpTF has almost the same spectral shape but different levels. The HMTF also appears to have the same tendency as the HpTF depending on the frequency. Therefore, the correlation between the average value of the HMTF (average value from 0.2 to 2 kHz) and the average value of the HpTF (average value from 0.2 to 4 kHz) collected by the inner microphone 140 in the low frequency band was confirmed. Furthermore, the correlation between the average value of the HMTF (average value from 2 to 4 kHz) and the average value of the HpTF (average value from 0.2 to 2 kHz) collected by the outer microphone 150 was confirmed. Note that the frequency bands for which the average values ​​are calculated do not have to be the same frequency band. In the experiment, three measurements were taken for each ear of 11 subjects, obtaining three logarithmic power spectra. The average power of the above-mentioned low frequency band was then calculated using the average of the three logarithmic power spectra. Therefore, the number of plotted points is 22 (both ears of 11 subjects). FIG. 8A is a diagram showing the correlation between the HMTF and HpTF collected by the inner microphone 140 without the reverse phase section 130. FIG. 8B is a diagram showing the correlation between the HMTF and HpTF collected by the outer microphone 150 without the reverse phase section 130. FIG. 9A is a diagram showing the correlation between the HMTF and HpTF collected by the inner microphone 140 with the reverse phase section 130. FIG. 9B is a diagram showing the correlation between the HMTF and HpTF collected by the outer microphone 150 with the reverse phase section 130. Note that the colors of the plotted points in FIGS. 8A, 8B, 9A, and 9B indicate the subjects, but are not used to distinguish between the 11 subjects because they are not relevant to determining the correlation. No correlation was observed between the HMTF and HpTF collected by the external microphone 150 without the anti-phase unit 130 shown in Fig. 8B, but a correlation coefficient r = 0.535 was observed in Fig. 8A, a correlation coefficient r = 0.582 in Fig. 9A, and a correlation coefficient r = 0.490 in Fig. 9B. It can be seen that even the correlation between average values ​​in the low frequency band is strong enough to select one HpTF from approximately three HpTFs. It is believed that if a model is generated that outputs an HpTF when information based on a sound signal is input, it will be possible to estimate the HpTF with even greater accuracy.

[0027] [Processor, Program, Recording Medium] The functions performed by the components described herein may be implemented in circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (a Central Processing Unit), conventional circuits, and / or combinations thereof, programmed to perform the described functions. A processor includes transistors and other circuits and is considered to be circuitry or processing circuitry. A processor may also be a programmed processor that executes a program stored in a memory.

[0028] In this specification, a circuitry, unit, or means is hardware that is programmed to realize or performs the described functions, which may be any hardware disclosed herein or any hardware known to be programmed to realize or perform the described functions.

[0029] If the hardware is a processor considered to be a type of circuitry, the circuitry, means, or unit is a combination of the hardware and software used to configure the hardware and / or processor.

[0030] The various processes described above can be implemented by loading a program that executes each step of the above method into the recording unit 2020 of the computer 2000 shown in Figure 10, and operating the control unit 2010, input unit 2030, output unit 2040, display unit 2050, etc.

[0031] The program describing the processing contents can be recorded on a computer-readable recording medium, which may be, for example, a magnetic recording device, an optical disk, a magneto-optical recording medium, a semiconductor memory, or any other suitable recording medium.

[0032] The program may be distributed by, for example, selling, transferring, lending, etc. portable recording media such as DVDs and CD-ROMs on which the program is recorded. Furthermore, the program may be stored in a storage device of a server computer, and then transferred from the server computer to other computers via a network, thereby distributing the program.

[0033] A computer that executes such a program may first temporarily store the program recorded on a portable recording medium or transferred from a server computer in its own storage device. Then, when executing a process, the computer reads the program stored on its own recording medium and executes the process in accordance with the read program. Alternatively, the computer may read the program directly from a portable recording medium and execute the process in accordance with the program. Furthermore, the computer may execute the process in accordance with the program each time a program is transferred from a server computer to the computer. Alternatively, the server computer may not transfer the program to the computer, but may instead execute the process through a so-called ASP (Application Service Provider) service, which realizes the processing function by issuing an execution instruction and obtaining the results. Furthermore, the server computer may execute the process at the terminal using a so-called SaaS (Software as a Service) service, which allows users to use part of a server computer along with the program. In this embodiment, the program includes information used for processing by an electronic computer that is equivalent to a program (such as data that is not a direct instruction to a computer but has properties that dictate computer processing).

[0034] Furthermore, in this embodiment, the device is configured by executing a predetermined program on a computer, but at least a part of the processing contents may be realized by hardware.

[0035] 20 Information collection system 100, 101 Acoustic device 110 Housing 120 Speaker 130 Reverse phase unit 140 Inner microphone 145 Microphone 150 Outer microphone 160 Measurement unit 170 Estimation unit 180 Correction unit 190 Mounting unit 200 Information collection device 210 Earplug microphone 220 Determination unit 230 Model generation unit 290 Recording unit 910 Cavity of concha 920 External auditory canal 930 Pinna

Claims

1. An acoustic device comprising: an open-ear housing; a speaker located on the cavity of the concha side of said housing; one or more microphones located on said housing; a measurement unit that picks up sound based on a predetermined signal with said microphone; an estimation unit that estimates an HpTF based on the sound signal picked up by said measurement unit; and a correction unit that corrects an input signal to said acoustic device using the estimated HpTF.

2. An acoustic device according to claim 1, wherein the estimation unit estimates the HpTF by selecting one HpTF from a plurality of predetermined HpTFs based on information correlated with the HpTF contained in the sound signal.

3. An information gathering system having an acoustic device and an information gathering device, wherein the acoustic device comprises an open-ear type housing, a speaker arranged on the cavity of the concha side of the housing, one or more microphones arranged on the housing, and a measuring unit that picks up sound based on a predetermined signal with the microphone, and the information gathering device comprises an earplug microphone, a determining unit that calculates an HpTF from the sound signal picked up by the earplug microphone of the sound based on the predetermined signal, and a recording unit that correlates and records information based on the sound signal picked up by the microphone for the same ear with the HpTF calculated by the determining unit.

4. An information collection system according to claim 3, wherein the information collection device also comprises a model generation unit that generates a model that outputs an HpTF when information based on a sound signal is input, from the HpTF associated with information based on the sound signal picked up by the microphone and recorded in the recording unit.

5. An acoustic device according to claim 1, wherein the estimation unit uses a model generated by the information collection system according to claim 4.

6. The acoustic device of claim 1 or the information gathering system of claim 3, wherein the microphones include an inner microphone arranged on the concha side of the housing and an outer microphone arranged on the opposite side of the concha side of the housing, and the acoustic device also includes an anti-phase unit that emits sound that is anti-phase to the speaker arranged on a side other than the concha side of the housing.

7. An information collection method using the information collection system of claim 3, comprising: an HMTF measurement step of attaching the housing to the ear without attaching the earplug microphone and collecting sound based on a predetermined signal with the microphone; an HpTF measurement step of attaching the housing to the ear with the earplug microphone attached and collecting sound based on a predetermined signal with the earplug microphone; a determination step in which the information collection device determines an HpTF based on the sound signal collected by the earplug microphone; a recording step in which the information collection device records information based on the sound signal collected by the microphone for the same ear, correlating it with the HpTF determined by the determination unit; and an HpTF association step of correlating information correlated with the HpTF contained in the sound signal with one HpTF out of a plurality of predetermined HpTFs, based on the HpTF determined by the determination unit.

8. A program for causing a computer to function as the estimation unit of the acoustic device of claim 1 or the decision unit and recording unit of the information collection device of claim 3.

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