WO2025017871A1 - Information processing system, information processing method, and recording medium - Google Patents

Abstract

An information processing system (10) comprises: a first terminal (100) that executes otoacoustic authentication which uses echo sounds that echo within the ear of a subject; a second terminal (200) by which a prescribed operation is enabled in accordance with the otoacoustic authentication; a detection means (210) that detects the amount of change in the distance between the first terminal and the second terminal; and a control means (220) which, when the amount of change in the distance has exceeded a prescribed value, executes notification to the first terminal and/or prohibition of the prescribed operation in the second terminal. According to such an information processing system, an appropriate measure can be executed when a terminal is lost or stolen.

Description

Information processing system, information processing method, and recording medium

This disclosure relates to the technical fields of information processing systems, information processing methods, and recording media.

Technology is known that performs authentication processing of a target (so-called ear acoustic authentication) based on characteristics of the ear canal obtained by using sound reverberation. For example, Patent Document 1 discloses a technology that performs ear acoustic authentication using sound waves obtained by earphones and unlocks a locked screen of an information communication device depending on the authentication result.

International Publication No. 2022/195792

The objective of this disclosure is to provide an information processing system, an information processing method, and a recording medium that are capable of taking appropriate measures in the event that a terminal is lost or stolen.

One aspect of the information processing system disclosed herein comprises a first terminal that performs ear acoustic authentication using sounds reverberating in a target's ear, a second terminal that is capable of performing a predetermined operation in response to the ear acoustic authentication, a detection means that detects the amount of change in the distance between the first terminal and the second terminal, and a control means that, when the amount of change in the distance exceeds a predetermined value, notifies the first terminal and/or prohibits the predetermined operation on the second terminal.

One aspect of the information processing method disclosed herein is an information processing method that uses at least one computer to control an information processing system that includes a first terminal that performs ear acoustic authentication using sounds reverberating in a target's ear, and a second terminal that is capable of performing a predetermined operation in response to the ear acoustic authentication, and detects a change in the distance between the first terminal and the second terminal, and when the change in the distance exceeds a predetermined value, at least one of notifying the first terminal and prohibiting the predetermined operation on the second terminal is executed.

One aspect of the recording medium of this disclosure is an information processing method for controlling an information processing system including at least one computer, a first terminal that performs ear acoustic authentication using sounds reverberating in a subject's ear, and a second terminal that is capable of performing a predetermined operation in response to the ear acoustic authentication, and a computer program recorded thereon for executing the information processing method includes detecting a change in distance between the first terminal and the second terminal, and, when the change in distance exceeds a predetermined value, at least one of notifying the first terminal and prohibiting the second terminal from performing the predetermined operation.

FIG. 2 is a block diagram showing a hardware configuration of a first information processing system. FIG. 2 is a block diagram showing a terminal configuration of the first information processing system. 11 is a flowchart showing a flow of operations in the first information processing system. 13 is a flowchart showing a flow of operations in a second information processing system. 13 is a flowchart showing a flow of operations in the third information processing system. 13 is a flowchart showing the flow of a registration operation in the fourth information processing system. FIG. 13 is a block diagram showing a terminal configuration of the fifth information processing system. 13 is a flowchart showing a flow of operations in the fifth information processing system.

Below, embodiments of an information processing system, an information processing method, and a recording medium will be described with reference to the drawings.

First Embodiment
The first information processing system will be described with reference to FIGS.

(Hardware configuration)
First, the hardware configuration of the first information processing system will be described with reference to Fig. 1. Fig. 1 is a block diagram showing the hardware configuration of the first information processing system.

As shown in FIG. 1, the first information processing system 10 includes a processor 11, a RAM (Random Access Memory) 12, a ROM (Read Only Memory) 13, and a storage device 14. The information processing system 10 may further include an input device 15 and an output device 16. The above-mentioned processor 11, RAM 12, ROM 13, storage device 14, input device 15, and output device 16 are each connected via a data bus 17. Note that the data bus 17 may be an interface other than a data bus (e.g., a LAN, a USB, etc.).

The processor 11 reads a computer program. For example, the processor 11 is configured to read a computer program stored in at least one of the RAM 12, the ROM 13, and the storage device 14. Alternatively, the processor 11 may read a computer program stored in a computer-readable storage medium using a storage medium reading device (not shown). The processor 11 may obtain (i.e., read) a computer program from a device (not shown) disposed outside the information processing system 10 via a network interface. The processor 11 controls the RAM 12, the storage device 14, the input device 15, and the output device 16 by executing the computer program that the processor 11 reads. In particular, in this embodiment, when the processor 11 executes the computer program that the processor 11 reads, a functional block for detecting the amount of change in the distance between the terminals and executing various controls is realized within the processor 11. In other words, the processor 11 may function as a controller that executes each control in the information processing system 10.

The processor 11 may be configured as, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an FPGA (field-programmable gate array), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), or a quantum processor. The processor 11 may be configured as one of these, or may be configured to use multiple processors in parallel.

RAM 12 temporarily stores computer programs executed by processor 11. RAM 12 temporarily stores data that processor 11 uses temporarily while processor 11 is executing a computer program. RAM 12 may be, for example, a D-RAM (Dynamic Random Access Memory) or an SRAM (Static Random Access Memory). Also, other types of volatile memory may be used instead of RAM 12.

ROM 13 stores computer programs executed by processor 11. ROM 13 may also store other fixed data. ROM 13 may be, for example, a P-ROM (Programmable Read Only Memory) or an EPROM (Erasable Read Only Memory). Also, other types of non-volatile memory may be used instead of ROM 13.

The storage device 14 stores data that the information processing system 10 stores long-term. The storage device 14 may operate as a temporary storage device for the processor 11. The storage device may store computer programs executed by the processor 11. The storage device 14 may include, for example, at least one of a hard disk device, a magneto-optical disk device, an SSD (Solid State Drive), and a disk array device.

The input device 15 is a device that receives input instructions from a user of the information processing system 10. The input device 15 may include, for example, at least one of a keyboard, a mouse, and a touch panel. The input device 15 may be configured as part of a smartphone, a tablet terminal, an earphone-type terminal, a watch-type terminal, etc. The input device 15 may be, for example, a device that allows voice input, including a microphone. The input device 15 may be, for example, one that is used only for maintenance. In such cases, the input device 15 may be appropriately omitted from the components when operating the information processing system 10.

The output device 16 is a device that outputs information related to the information processing system 10 to the outside. For example, the output device 16 may be a display device (e.g., a display) that can display information related to the information processing system 10. The output device 16 may also be a speaker or the like that can output information related to the information processing system 10 as audio. The output device 16 may be configured as part of a smartphone, a tablet terminal, an earphone-type terminal, a watch-type terminal, or the like.

The first information processing system 10 is configured to include a first terminal and a second terminal, as described below. Each component described in FIG. 1 may be configured to be included in at least one of the first terminal and the second terminal included in the first information processing system 10. Also, some of the components described in FIG. 1 may be configured to be included in an external device (e.g., an external server, a cloud, etc.) different from the first terminal and the second terminal.

(Terminal configuration)
Next, a terminal configuration of the first information processing system 10 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing a terminal configuration of the first information processing system.

In FIG. 2, the first information processing system 10 includes a first terminal 100 and a second terminal 200. The first terminal 100 and the second terminal 200 are connected, for example, by wireless communication, and are configured to be able to transmit and receive information to and from each other. The first terminal 100 is configured, for example, as an earphone-type hearable terminal, and includes an ear acoustic authentication unit 110 as a processing block for realizing its functions. The second terminal 200 is configured, for example, as a mobile terminal such as a smartphone, tablet terminal, or watch-type terminal, and includes a detection unit 210 and a control unit 220 as processing blocks for realizing its functions. Each of the ear acoustic authentication unit 110, detection unit 210, and control unit 220 may be a processing block configured, for example, by the above-mentioned processor 11 (see FIG. 1).

The earacoustic authentication unit 110 is configured to perform earacoustic authentication using a reverberant sound reverberated in the ear of the subject. The earacoustic authentication unit 110 controls the first terminal 100, for example, worn in the ear of the subject, to acquire a reverberant sound signal including characteristics of the ear of the subject (specifically, characteristics of the internal shape of the ear). More specifically, the earacoustic authentication unit 110 controls the first terminal 100 to send sound waves into the ear of the subject, and acquires a reverberant sound signal based on the reverberant sound of the sent sound waves. The earacoustic authentication unit 110 then performs earacoustic authentication using the acquired reverberant sound signal. The earacoustic authentication unit 110 performs earacoustic authentication, for example, by matching a feature extracted from the reverberant sound signal with a feature of a registered user that has been registered in advance. The earacoustic authentication unit 110 may perform earacoustic authentication, for example, when the subject wears the first terminal 100. The earacoustic authentication unit 110 may also perform earacoustic authentication periodically at a predetermined period after the subject wears the first terminal 100. The ear acoustic authentication unit 110 may perform ear acoustic authentication when the subject performs an operation to perform authentication.

The authentication result by the ear acoustic authentication unit 110 is transmitted to the second terminal 200. The second terminal 200 then permits a specific operation on the second terminal 200 according to the received authentication result. The specific operation may include all operations that can be performed on the second terminal 200, or may be some of the operations that can be performed on the second terminal 200. For example, if the second terminal 200 is configured as a smartphone, the smartphone may be configured to unlock the lock screen on the condition that the ear acoustic authentication is successful. In this case, if the ear acoustic authentication is successful, the smartphone can be operated in general. Alternatively, the smartphone may be configured to be configured to allow the use of various apps on the smartphone on the condition that the ear acoustic authentication is successful. Note that the specific operation on the second terminal 200 may be permitted by authentication other than the ear acoustic authentication on the second terminal 200 (for example, face authentication, fingerprint authentication, passcode authentication, etc.). In this case, the ear acoustic authentication on the first terminal 100 may skip other authentication on the second terminal 200 and allow the specific operation.

The detection unit 210 is configured to be able to detect the amount of change in the distance between the first terminal 100 and the second terminal 200. The detection unit 210 may detect the amount of change in the distance, for example, by detecting the distance between the first terminal 100 and the second terminal 200 multiple times and comparing the detected distances. In this case, the detection unit 210 may estimate the distance between the first terminal 100 and the second terminal 200 using, for example, a Global Positioning System (GPS). Alternatively, the detection unit 210 may detect the amount of change in the distance, with the position when the first terminal 100 and the second terminal 200 are in contact being set as the origin. Specifically, the detection unit 210 detects the acceleration applied to each of the first terminal 100 and the second terminal 200 after they are in contact. Then, the amount of change in the distance between the first terminal 100 and the second terminal 200 may be calculated by calculating the position change from the origin based on the detected acceleration. The detection unit 210 may be configured to detect the amount of change in the distance between the first terminal 100 and the second terminal 200 when the subject is using at least one of the first terminal 100 and the second terminal 200. Alternatively, the detection unit 210 may be configured to detect the amount of change in the distance between the first terminal 100 and the second terminal 200 even when the subject is not using either the first terminal 100 or the second terminal 200. The amount of change in the distance detected by the detection unit 210 is configured to be output to the control unit 220.

The control unit 220 is configured to be able to control at least one of the first terminal 100 and the second terminal 200 according to the amount of change in the distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210. Specifically, the control unit 220 is configured to be able to execute at least one of notifying the first terminal 100 and prohibiting a predetermined operation on the second terminal 200 when the amount of change in the distance between the first terminal 100 and the second terminal 200 exceeds a predetermined value. Note that the "predetermined value" here is a threshold value for determining that the subject is no longer holding at least one of the first terminal 100 and the second terminal 200. For example, when the subject leaves the second terminal 200 behind while still wearing the first terminal 100 on his/her ear and starts moving, the amount of change in the distance between the first terminal 100 and the second terminal 200 may be set to exceed the predetermined value. Alternatively, if a subject is wearing the first terminal 100 on his/her ear and a person other than the subject tries to steal the second terminal 200 and run away, the change in the distance between the first terminal 100 and the second terminal 200 may be set to exceed a predetermined value.

The notification by the control unit 220 to the first terminal 100 may be any notification that some abnormality has occurred to the target. The content of the notification to the target may include information for notifying the target that the second terminal 200 has been lost or stolen. For example, the control unit 220 may perform control such as outputting an alarm sound, a message, or the like from the first terminal 100. The control unit 220 may change the content of the notification to the first terminal 100 depending on the situation. For example, when the control unit 220 determines that the target is highly likely to have left the second terminal 200 behind, it may perform a notification to notify the target that the second terminal 200 has been left behind. When the control unit 220 determines that the target is highly likely to have stolen the second terminal 200 by a person other than the target, it may perform a notification to notify the target that the second terminal 200 has been stolen. These situation determinations may be performed based on the amount of change in the distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210, for example. For example, if the amount of change in distance exceeds a first predetermined value, it may be determined that the subject has likely left the second terminal 200 behind, and if the amount of change in distance exceeds a second predetermined value that is higher than the first predetermined value, it may be determined that a person other than the subject has likely stolen the second terminal 200. In this way, the control unit 220 may change the notification mode to the first terminal 100 depending on the amount of change in distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210.

The control unit 220 may prohibit a specific operation on the second terminal 200 regardless of the authentication result of the ear acoustic authentication by the ear acoustic authentication unit 110. For example, even in a situation where the ear acoustic authentication is successful and a specific operation on the second terminal 200 would normally be permitted, the control unit 220 may prohibit the specific operation on the second terminal 200. Furthermore, the control unit 220 may prohibit a specific operation on the second terminal 200 regardless of an authentication result other than that of the ear acoustic authentication unit 110 (for example, the result of another authentication process on the second terminal 200). For example, even in a situation where another authentication process on the second terminal 200 is successful and a specific operation on the second terminal 200 would normally be permitted, the control unit 220 may prohibit the specific operation on the second terminal 200.

In the above example, the first terminal 100 is configured to include the ear acoustic authentication unit 110, but the second terminal 200 may be configured to include the ear acoustic authentication unit 110. In this case, the first terminal 100 transmits a reverberation signal acquired from the target ear to the second terminal 200. The ear acoustic authentication unit 110 included in the second terminal 200 may then perform ear acoustic authentication using the reverberation signal received from the first terminal 100. Furthermore, in the above example, the second terminal 200 is configured to include the detection unit 210 and the control unit 220, but the first terminal 100 may be configured to include both or either of the detection unit 210 and the control unit 220. When the first terminal 100 includes both the detection unit 210 and the control unit 220, the detection unit 210 in the first terminal 100 detects the amount of change in the distance between the first terminal 100 and the second terminal 200. Then, the control unit 220 in the first terminal 200 may execute the notification in the first terminal 100 and transmit a signal to the second terminal 200 to prohibit a predetermined operation. Furthermore, in the above example, a notification is given to the first terminal 100, but a notification may also be given to the second terminal 200. That is, a notification may be given to the second terminal 200 in addition to or instead of the first terminal 100. Furthermore, in the above example, a predetermined operation is prohibited in the second terminal, but a predetermined operation in the first terminal may be prohibited. That is, a predetermined operation in the first terminal 100 (for example, an operation related to music playback in an earphone-type terminal) may be prohibited in addition to or instead of the second terminal 200.

(Operation flow)
Next, the flow of operations of the first information processing system 10 will be described with reference to Fig. 3. Fig. 3 is a flowchart showing the flow of operations in the first information processing system.

As shown in FIG. 3, when the operation of the first information processing system 10 is started, the detection unit 210 first detects the amount of change in the distance between the first terminal 100 and the second terminal 200 (step S101). The detection unit 210 outputs information related to the detected amount of change in distance to the control unit 220.

The control unit 220 then determines whether the amount of change in distance detected by the detection unit 210 exceeds a predetermined value (step S102). If the amount of change in distance does not exceed the predetermined value (step S102: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time.

On the other hand, if the change in distance exceeds the predetermined value (step S102: YES), the control unit 220 executes a notification to the first terminal 100 (step S103). The control unit 220 also prohibits a predetermined operation on the second terminal 200 (step S104). Note that the control unit 220 may execute the processes of steps S103 and S104 one after the other, or may execute them simultaneously in parallel. Also, the control unit 220 may execute only one of the processes of steps S103 and S104.

(Technical effect)
Next, the technical effects obtained by the first information processing system 10 will be described.

1 to 3, in the first information processing system 10, when the amount of change in the distance between the first terminal 100 and the second terminal 200 exceeds a predetermined value, at least one of notifying the first terminal 100 and prohibiting a predetermined operation on the second terminal 200 is performed. In this way, it is possible to take appropriate measures when a terminal is lost or stolen.
For example, when the subject leaves the second terminal 200 behind or when the second terminal 200 is stolen, the subject can be promptly notified of the occurrence of the leaving or theft. In addition, it is possible to prohibit a specific operation on the second terminal 200, thereby preventing the second terminal from being illegally operated by a person other than the subject.

Second Embodiment
The second information processing system 10 will be described with reference to Fig. 4. The second information processing system 10 differs from the first information processing system 10 described above only in some operations, and other parts may be similar to the first information processing system 10. Therefore, hereinafter, parts that differ from the first embodiment will be described in detail, and explanations of other overlapping parts will be omitted as appropriate.

(Operation flow)
First, the flow of operations of the second information processing system 10 will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the flow of operations in the second information processing system. Note that in Fig. 4, the same processes as those shown in Fig. 3 are denoted by the same reference numerals.

As shown in FIG. 4, when the operation of the second information processing system 10 is started, the detection unit 210 first detects the amount of change in the distance between the first terminal 100 and the second terminal 200 (step S101). The detection unit 210 outputs information related to the detected amount of change in distance to the control unit 220.

The control unit 220 then determines whether the amount of change in distance detected by the detection unit 210 exceeds a predetermined value (step S102). If the amount of change in distance does not exceed the predetermined value (step S102: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time.

On the other hand, if the amount of change in distance exceeds the predetermined value (step S102: YES), the detection unit 210 detects the inter-terminal distance between the first terminal 100 and the second terminal 200 (step S201). That is, the detection unit 210 in the second information processing device 10 is configured to be able to detect the inter-terminal distance between the first terminal 100 and the second terminal 200 in addition to the amount of change in distance between the first terminal 100 and the second terminal 200. The detection unit 210 may, for example, detect a sound output from the second terminal 200 at the first terminal 100 and estimate the inter-terminal distance according to the sound pressure at that time. Conversely, the detection unit 210 may detect a sound output from the first terminal 100 at the second terminal 200 and estimate the inter-terminal distance according to the sound pressure at that time. The detection unit 210 may detect the inter-terminal distance again in step S201, but if the inter-terminal distance is detected when detecting the amount of change in the distance (i.e., in step S101), that value may be used as is. The detection unit 210 outputs information related to the detected inter-terminal distance to the control unit 220.

Then, the control unit 220 judges whether the inter-terminal distance detected by the detection unit 210 exceeds the predetermined distance continuously for a predetermined time (step S202). The "predetermined distance" here is a value that is set in advance as a threshold for judging whether the first terminal 100 and the second terminal 200 are far enough apart to judge that misplacement, theft, etc. has occurred. For example, if the first terminal and the second terminal 200 are only a few meters apart, it is unlikely that misplacement or theft has occurred. On the other hand, if the first terminal and the second terminal 200 are several hundred meters apart, it can be judged that misplacement or theft has occurred. The predetermined distance may be set as a threshold for judging such a situation. The "predetermined time" is a threshold that is set to avoid an instantaneous increase in the inter-terminal distance or erroneous detection of the inter-terminal distance. For example, even if the inter-terminal distance temporarily exceeds several tens of meters, if the inter-terminal distance immediately returns to a few meters thereafter, it is unlikely that misplacement or theft has occurred. On the other hand, if the distance between the devices exceeds several tens of meters and continues for more than an hour, it can be determined that there is a high possibility that the device has been left behind or stolen. The predetermined time can be set as a threshold for determining such a situation.

If the inter-terminal distance detected by the detection unit 210 does not exceed the predetermined distance for a predetermined consecutive time (step S202: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time. On the other hand, if the inter-terminal distance exceeds the predetermined distance for a predetermined consecutive time (step S202: YES), the control unit 220 executes a notification to the first terminal 100 (step S103). In addition, the control unit 220 prohibits a predetermined operation on the second terminal 200 (step S104).

(Technical effect)
Next, the technical effects obtained by the second information processing system 10 will be described.

As described in FIG. 4, in the second information processing system 10, in addition to determining whether the amount of change in the distance between the first terminal 100 and the second terminal 200 exceeds a predetermined value, it is also determined whether the distance between the terminals exceeds a predetermined distance for a predetermined consecutive period of time. In this way, it is possible to prevent a notification to the first terminal 100 or a predetermined operation on the second terminal 200 from being prohibited in cases such as when the distance between the terminals temporarily increases or when an erroneous detection of the distance between the terminals occurs.

Third Embodiment
The third information processing system 10 will be described with reference to Fig. 5. The third information processing system 10 differs from the first and second information processing systems 10 described above only in some operations, and other parts may be similar to the first and second information processing systems 10. Therefore, hereinafter, parts that differ from the embodiments already described will be described in detail, and explanations of other overlapping parts will be omitted as appropriate.

(Operation flow)
First, the flow of operations of the third information processing system 10 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing the flow of operations in the third information processing system. Note that in Fig. 5, the same processes as those shown in Fig. 3 are denoted by the same reference numerals.

As shown in FIG. 5, when the operation of the third information processing system 10 is started, the detection unit 210 first detects the amount of change in the distance between the first terminal 100 and the second terminal 200 (step S101). The detection unit 210 outputs information related to the detected amount of change in distance to the control unit 220.

The control unit 220 then determines whether the amount of change in distance detected by the detection unit 210 exceeds a predetermined value (step S102). If the amount of change in distance does not exceed the predetermined value (step S102: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time.

On the other hand, if the amount of change in distance exceeds the predetermined value (step S102: YES), the detection unit 210 detects the inter-terminal distance between the first terminal 100 and the second terminal 200 (step S301). That is, the detection unit 210 in the third information processing device 10 is configured to be able to detect the inter-terminal distance between the first terminal 100 and the second terminal 200, similar to the second information processing device 10. The detection unit 210 outputs information related to the detected inter-terminal distance to the control unit 220.

The control unit 220 then determines whether the inter-terminal distance detected by the detection unit 210 is increasing over time (step S302). The control unit 220 may determine that the inter-terminal distance is increasing over time if the inter-terminal distance is increasing monotonically. Alternatively, the control unit 220 may determine that the inter-terminal distance is increasing over time if the inter-terminal distance continues to increase overall, even if it temporarily decreases. Note that the control unit 220 may determine whether the inter-terminal distance is increasing over time for only a certain period of time after the inter-terminal distance begins to increase. This is because, for example, even if the second terminal 200 is left behind or stolen, it is considered that the inter-terminal distance will not increase any further after a certain amount of time has passed (in other words, after it has moved a certain distance away).

If the inter-terminal distance detected by the detection unit 210 has not increased over time (step S302: NO), the subsequent processing will be omitted. In this case, the operation of step S101 may be started again after a predetermined period of time. On the other hand, if the inter-terminal distance has increased over time (step S302: YES), the control unit 220 executes a notification to the first terminal 100 (step S103). In addition, the control unit 220 prohibits a predetermined operation on the second terminal 200 (step S104).

(Technical effect)
Next, the technical effects obtained by the third information processing system 10 will be described.

As described in FIG. 5, in the third information processing system 10, in addition to determining whether the amount of change in the distance between the first terminal 100 and the second terminal 200 exceeds a predetermined value, it is also determined whether the distance between the terminals is increasing over time. In this way, it is possible to prevent a notification from being sent to the first terminal 100 or a specific operation from being prohibited on the second terminal 200 in cases such as when the distance between the terminals temporarily increases or when an erroneous detection of the distance between the terminals occurs.

Fourth Embodiment
The fourth information processing system 10 will be described with reference to Fig. 6. The fourth information processing system 10 differs from the first to third information processing systems 10 described above only in some of its operations, and other parts may be similar to the first to third information processing systems 10. Therefore, hereinafter, parts that differ from the embodiments already described will be described in detail, and explanations of other overlapping parts will be omitted as appropriate.

(Operation flow)
First, the flow of operations of the fourth information processing system 10 will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the flow of operations in the fourth information processing system. Note that in Fig. 6, the same processes as those shown in Fig. 3 are denoted by the same reference numerals.

As shown in FIG. 6, when the operation of the fourth information processing system 10 is started, the detection unit 210 first detects the amount of change in the distance between the first terminal 100 and the second terminal 200 (step S101). The detection unit 210 outputs information related to the detected amount of change in distance to the control unit 220.

The control unit 220 then determines whether the amount of change in distance detected by the detection unit 210 exceeds a predetermined value (step S102). If the amount of change in distance does not exceed the predetermined value (step S102: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time.

On the other hand, if the change in distance exceeds the predetermined value (step S102: YES), the detection unit 210 detects the acceleration difference between the first terminal 100 and the second terminal 200 (step S401). That is, the detection unit 210 in the fourth information processing device 10 is configured to be able to detect the acceleration difference between the first terminal 100 and the second terminal 200 in addition to the change in distance between the first terminal 100 and the second terminal 200. The detection unit 210 may detect the acceleration difference between the first terminal 100 and the second terminal 200 by, for example, acquiring the acceleration of the first terminal 100 and the acceleration of the second terminal 200, respectively, and calculating the difference between them. The accelerations of the first terminal 100 and the second terminal 200 may be detected by a sensor or the like provided in each terminal. The detection unit 210 outputs the detected acceleration difference between the first terminal 100 and the second terminal 200 to the control unit 220.

Then, the control unit 220 judges whether the acceleration difference detected by the detection unit 210 exceeds a predetermined threshold value (step S402). The "predetermined threshold value" here is a value that is set in advance as a threshold value for judging whether there is a large difference between the acceleration of the first terminal 100 and the acceleration of the second terminal 200 to the extent that it can be judged that the terminal has been left behind or stolen. For example, if a subject wearing the first terminal 100 leaves the second terminal 200 in a bus and gets off the bus, the acceleration of the first terminal 100 will be a value corresponding to the walking of the subject, and the acceleration of the second terminal 200 will be a value corresponding to the running of the bus. In addition, if a third party steals the second terminal 200 from the subject wearing the first terminal 100 and runs away on a bicycle, the acceleration of the first terminal 100 will be a value corresponding to the walking of the subject, and the acceleration of the second terminal 200 will be a value corresponding to the running of the bicycle. In this way, when the terminal has been left behind or stolen, it is expected that a large acceleration difference will occur between the first terminal 100 and the second terminal 200. The specified threshold can be set as a threshold for determining such a situation.

If the acceleration difference detected by the detection unit 210 does not exceed the predetermined threshold (step S402: NO), the subsequent processing is omitted. In this case, the operation of step S101 may be started again after a predetermined period of time. On the other hand, if the acceleration difference exceeds the predetermined threshold (step S402: YES), the control unit 220 executes a notification to the first terminal 100 (step S103). In addition, the control unit 220 prohibits a predetermined operation on the second terminal 200 (step S104).

(Technical effect)
Next, the technical effects obtained by the fourth information processing system 10 will be described.

As described in FIG. 6, in the fourth information processing system 10, in addition to determining whether the amount of change in distance between the first terminal 100 and the second terminal 200 exceeds a predetermined value, it is also determined whether the difference in acceleration between the first terminal 100 and the second terminal 200 exceeds a predetermined threshold. In this way, it is possible to determine whether a device has been left behind or stolen from the difference between the acceleration of the first terminal 100 and the acceleration of the second terminal 200 (in other words, the difference in their respective movement patterns). This makes it possible to notify the first terminal 100 and prohibit certain operations on the second terminal 200 at a more appropriate time.

Fifth Embodiment
The fifth information processing system 10 will be described with reference to Figures 7 and 8. The fifth information processing system 10 differs only in part of the configuration and operation from the first to fourth information processing systems 10 described above, and other parts may be similar to the first to fourth information processing systems 10. For this reason, hereinafter, parts that differ from the embodiments already described will be described in detail, and explanations of other overlapping parts will be omitted as appropriate.
(Terminal configuration)
First, the terminal configuration of the fifth information processing system 10 will be described with reference to Fig. 7. Fig. 7 is a block diagram showing the terminal configuration of the fifth information processing system.

7, the fifth information processing system 10 is configured to include a first terminal 100, a second terminal 200, and a third terminal 300. That is, the fifth information processing system 10 further includes a third terminal 300 in addition to the configuration described in the first embodiment (see FIG. 2). The third terminal 300 is a terminal connected to the first terminal 100 by wireless communication or the like, similar to the second terminal 200. The third terminal 300 may also be a terminal connected to the second terminal 200. That is, the first terminal 100, the second terminal 200, and the third terminal 300 may each be configured to be able to transmit and receive information to and from each other. For example, if the first terminal 100 is an earphone-type hearable terminal and the second terminal 200 is a smartphone, the third terminal may be configured as a smart watch. These terminals may be paired with each other to be able to communicate with each other.

The third terminal 300 is configured to include a detection unit 310 and a control unit 320. The detection unit 310 and the control unit 320 in the third terminal 300 may have the same functions as the detection unit 210 and the control unit 220 in the second terminal 200 already described. Specifically, the detection unit 310 may be configured to detect the amount of change in the distance between the first terminal 100 and the third terminal 300. The control unit 220 may be configured to control at least one of the first terminal 100 and the third terminal 300 according to the amount of change in the distance between the first terminal 100 and the third terminal 300 detected by the detection unit 310. Specifically, the control unit 320 may be configured to execute at least one of notifying the first terminal 100 and prohibiting a predetermined operation in the third terminal 300 when the amount of change in the distance between the first terminal 100 and the third terminal 300 exceeds a predetermined value.

(Operation flow)
Next, the flow of operations of the fifth information processing system 10 will be described with reference to Fig. 8. Fig. 8 is a flowchart showing the flow of operations in the fifth information processing system.

As shown in FIG. 8, when the operation of the fifth information processing system 10 is started, the detection unit 210 in the second terminal 200 first detects the amount of change in the distance between the first terminal 100 and the second terminal 200. The detection unit 310 in the third terminal 300 detects the amount of change in the distance between the first terminal 100 and the third terminal 300. The fifth information processing device 10 detects the amount of change in the distance between multiple terminals in this manner (step S501).

Then, the control unit 220 in the second terminal 200 determines whether the amount of change in the distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210 exceeds a predetermined value. The control unit 320 in the third terminal 300 determines whether the amount of change in the distance between the first terminal 100 and the third terminal 300 detected by the detection unit 310 exceeds a predetermined value. The fifth information processing device 10 detects whether the amount of change in any of the distances detected in this manner exceeds a predetermined value (step S502). Note that if the amount of change in any of the distances does not exceed the predetermined value (step S502: NO), the subsequent processing is omitted. In this case, the operation of step S501 may be started again after a predetermined period of time.

On the other hand, if the amount of change in any of the distances exceeds the predetermined value (step S502: YES), the control unit 220 or the control unit 320 executes a notification to the first terminal 100 (step S503). Specifically, if the amount of change in the distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210 in the second terminal 200 exceeds the predetermined value, the control unit 220 in the second terminal 200 executes a notification to the first terminal 100. Similarly, if the amount of change in the distance between the first terminal 100 and the third terminal 300 detected by the detection unit 310 in the third terminal 300 exceeds the predetermined value, the control unit 320 in the third terminal 300 executes a notification to the first terminal 100.

Furthermore, the control unit 220 or the control unit 320 prohibits a predetermined operation on the second terminal 200 or the third terminal 300 (step S504). Specifically, when the amount of change in the distance between the first terminal 100 and the second terminal 200 detected by the detection unit 210 in the second terminal 200 exceeds a predetermined value, the control unit 220 in the second terminal 200 prohibits a predetermined operation on the second terminal 200. Similarly, when the amount of change in the distance between the first terminal 100 and the third terminal 300 detected by the detection unit 310 in the third terminal 300 exceeds a predetermined value, the control unit 320 in the third terminal 300 prohibits a predetermined operation on the third terminal. Note that the control unit 220 and the control unit 320 may execute the processes of steps S503 and S504 one after the other, or may execute them simultaneously in parallel. Also, the control unit 220 and the control unit 320 may execute only one of the processes of steps S503 and S504.

In the above example, a configuration was described in which the amount of change in distance between the first terminal 100 and the second terminal 200 and the amount of change in distance between the first terminal 100 and the third terminal 300 was used, but the amount of change in distance between the second terminal 200 and the third terminal 300 may also be detected. For example, at least one of the detection unit 210 in the second terminal 200 and the detection unit 310 in the third terminal 300 may detect the amount of change in distance between the second terminal 200 and the third terminal 300.

In the above configuration, when the change in the distance between the second terminal 200 and the third terminal 300 exceeds a predetermined value, a notification may be sent to at least one of the second terminal 200 and the third terminal 300 in addition to or instead of the first terminal 100. For example, when it is determined that there is a risk of the second terminal 200 being lost or stolen based on the change in the distance between the terminals, a notification may be sent to the third terminal 300 in addition to or instead of the first terminal 100. Also, when it is determined that there is a risk of the third terminal 300 being lost or stolen based on the change in the distance between the terminals, a notification may be sent to the second terminal 200 in addition to or instead of the first terminal 100. Note that when it is not possible to determine from the change in the distance between the terminals whether there is a risk of the second terminal 200 being lost or stolen or the third terminal 300 being lost or stolen, a notification may be sent to both the second terminal 200 and the third terminal 300. Alternatively, notification may be sent to the device with the highest priority based on pre-set priorities.

In the above configuration, when the change in the distance between the second terminal 200 and the third terminal 300 exceeds a predetermined value, a predetermined operation on at least one of the second terminal 200 and the third terminal 300 may be prohibited. For example, when it is determined based on the change in the distance between the terminals that the second terminal 200 is at risk of being lost or stolen, a predetermined operation on the second terminal 200 may be prohibited. Also, when it is determined based on the change in the distance between the terminals that the third terminal 300 is at risk of being lost or stolen, a predetermined operation on the third terminal 300 may be prohibited. Note that when it is not possible to determine from the change in the distance between the terminals whether the second terminal 200 is at risk of being lost or stolen or the third terminal 300 is at risk of being lost or stolen, a predetermined operation on both the second terminal 200 and the third terminal 300 may be prohibited. Alternatively, a predetermined operation on the terminal with a higher priority may be prohibited based on a preset priority.

(Technical effect)
Next, the technical effects obtained by the fifth information processing system 10 will be described.

As described in Figures 7 and 8, in the fifth information processing system 10, based on the amount of change in the distance between multiple terminals, at least one of notifying the first terminal 100 and prohibiting a specific operation on the second terminal 200 and the third terminal 300 is performed. In this way, even if a user owns multiple terminals, it is possible to take appropriate measures if one of the terminals is lost or stolen. Note that while the above example was described using an example in which three terminals are connected, the same technical effect can be achieved by performing the same process even when four or more terminals are connected.

The scope of each embodiment also includes a processing method in which a program that operates the configuration of each embodiment to realize the functions of the above-mentioned embodiments is recorded on a recording medium, the program recorded on the recording medium is read as code, and executed on a computer. In other words, computer-readable recording media are also included in the scope of each embodiment. Furthermore, each embodiment includes not only the recording medium on which the above-mentioned program is recorded, but also the program itself.

The recording medium may be, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, magnetic tape, non-volatile memory card, or ROM. In addition, the scope of each embodiment is not limited to programs recorded on the recording medium that execute processes by themselves, but also includes programs that operate on an OS in conjunction with other software or functions of an expansion board to execute processes. Furthermore, the program itself may be stored on a server, and part or all of the program may be made downloadable from the server to a user terminal. The program may be provided to the user in, for example, a SaaS (Software as a Service) format.

<Additional Notes>
The above-described embodiment may be further described as follows, but is not limited to the following.

(Appendix 1)
The information processing system described in Appendix 1 is an information processing system comprising a first terminal that performs ear acoustic authentication using sound reverberating in a target's ear, a second terminal that is capable of performing a specified operation in response to the ear acoustic authentication, a detection means for detecting a change in distance between the first terminal and the second terminal, and a control means that, when the change in distance exceeds a specified value, performs at least one of notifying the first terminal and prohibiting the specified operation on the second terminal.

(Appendix 2)
The information processing system described in Appendix 2 is the information processing system described in Appendix 1, wherein the control means executes at least one of notifying the first terminal and prohibiting the specified operation on the second terminal when the amount of change in the distance exceeds the specified value and the inter-terminal distance between the first terminal and the second terminal exceeds the specified distance for a specified continuous period of time.

(Appendix 3)
The information processing system described in Appendix 3 is the information processing system described in Appendix 1 or 2, wherein the control means executes at least one of notifying the first terminal and prohibiting the specified operation on the second terminal when the amount of change in the distance exceeds the specified value and the inter-terminal distance between the first terminal and the second terminal is increasing over time.

(Appendix 4)
The information processing system described in Appendix 4 is the information processing system described in any one of Appendixes 1 to 3, wherein the control means executes at least one of notifying the first terminal and prohibiting the specified operation on the second terminal when the amount of change in distance exceeds the specified value and the difference in acceleration between the first terminal and the second terminal exceeds a specified threshold.

(Appendix 5)
The information processing method described in Appendix 5 is an information processing method for controlling, by at least one computer, an information processing system including a first terminal that performs ear acoustic authentication using reverberation sound reverberating in a target's ear, and a second terminal that is capable of performing a specified operation in response to the ear acoustic authentication, the information processing method detecting a change in distance between the first terminal and the second terminal, and when the change in distance exceeds a specified value, at least one of notifying the first terminal and prohibiting the specified operation on the second terminal.

(Appendix 6)
The recording medium described in Appendix 6 is a recording medium on which a computer program is recorded that executes an information processing method for controlling an information processing system that includes at least one computer, a first terminal that performs ear acoustic authentication using reverberation sound reverberating in a target's ear, and a second terminal that is capable of performing a specified operation in response to the ear acoustic authentication, the information processing method detecting a change in distance between the first terminal and the second terminal, and, when the change in distance exceeds a specified value, at least one of notifying the first terminal and prohibiting the specified operation in the second terminal.

(Appendix 7)
The computer program described in Appendix 7 is an information processing method for controlling an information processing system including at least one computer, a first terminal that performs ear acoustic authentication using reverberation sound reverberating in a target's ear, and a second terminal that is capable of performing a specified operation in response to the ear acoustic authentication, the computer program executing the information processing method detecting a change in distance between the first terminal and the second terminal, and when the change in distance exceeds a specified value, at least one of notifying the first terminal and prohibiting the specified operation on the second terminal.

This disclosure may be modified as appropriate within the scope that does not contradict the gist or idea of the invention that can be read from the claims and the entire specification, and information processing systems, information processing methods, and recording media that involve such modifications are also included in the technical ideas of this disclosure.

REFERENCE SIGNS LIST 10 Information processing system 11 Processor 100 First terminal 110 Ear acoustic authentication unit 200 Second terminal 210 Detection unit 220 Control unit 300 Third terminal 310 Detection unit 320 Control unit

Claims (6)

A first terminal that performs ear acoustic authentication using echo sounds echoed in a subject's ear;
a second terminal capable of performing a predetermined operation in response to the ear acoustic authentication;
A detection means for detecting a change in distance between the first terminal and the second terminal;
a control means for executing at least one of a notification to the first terminal and a prohibition of the predetermined operation on the second terminal when the amount of change in the distance exceeds a predetermined value;
An information processing system comprising: the control means, when the amount of change in the distance exceeds the predetermined value and the inter-terminal distance between the first terminal and the second terminal exceeds the predetermined distance for a predetermined consecutive time, executes at least one of notifying the first terminal and prohibiting the predetermined operation in the second terminal.
The information processing system according to claim 1 . the control means, when the amount of change in the distance exceeds the predetermined value and the inter-terminal distance between the first terminal and the second terminal increases over time, executes at least one of notifying the first terminal and prohibiting the predetermined operation in the second terminal.
3. The information processing system according to claim 1 or 2. the control means, when the amount of change in the distance exceeds the predetermined value and the difference in acceleration between the first terminal and the second terminal exceeds a predetermined threshold, executes at least one of notifying the first terminal and prohibiting the predetermined operation in the second terminal.
3. The information processing system according to claim 1 or 2. by at least one computer,
A first terminal that performs ear acoustic authentication using echo sounds echoed in a subject's ear;
a second terminal capable of performing a predetermined operation in response to the ear acoustic authentication;
An information processing method for controlling an information processing system comprising:
Detecting a change in distance between the first terminal and the second terminal;
When the amount of change in the distance exceeds a predetermined value, at least one of notifying the first terminal and prohibiting the second terminal from performing the predetermined operation is executed.
Information processing methods. At least one computer
A first terminal that performs ear acoustic authentication using echo sounds echoed in a subject's ear;
a second terminal capable of performing a predetermined operation in response to the ear acoustic authentication;
An information processing method for controlling an information processing system comprising:
Detecting a change in distance between the first terminal and the second terminal;
When the amount of change in the distance exceeds a predetermined value, at least one of notifying the first terminal and prohibiting the second terminal from performing the predetermined operation is executed.
A recording medium on which a computer program for executing an information processing method is recorded.