Image processing device, image processing method, and recording medium

Abstract

The present invention comprises: an image acquisition unit 111 for acquiring an image I captured such that a fluorescent marker FM that emits light in a dark location is included in the angle of view; an assessment unit 112 for assessing whether or not to switch a power consumption mode, in accordance with the emission state of the fluorescent marker FM included in the image I; and a switching unit 113 for switching the power consumption mode in accordance with the result of assessment by the assessment unit 112.

Description

[Technical Field]

[0001] The present disclosure relates to the technical fields of an image processing device, an image processing method, and a recording medium. [Background technology]

[0002] Patent Document 1 describes a control of a subject authentication device that performs an authentication process to authenticate a subject based on an image of the subject captured by a photographing means, including an authentication repeat process that repeats the authentication process even after the authentication process determines that the subject is a match, a repeat stop instruction receiving process that receives a repeat stop instruction from an input means to stop the repeat of the authentication process, a truth determination process that compares the received repeat stop instruction with a pre-registered normal instruction to determine whether it is true or false, and a repeat stop process that stops the authentication repeat process if the determination result of the truth determination process is true, thereby improving security reliability against impersonation and reducing power consumption. Also, Patent Document 2 describes an intruder detection device that performs monitoring using a black-and-white surveillance camera that is installed in a no-entry zone having a transparent window surface and can only capture an area that is irradiated with infrared rays, in which an infrared irradiator is provided that irradiates infrared rays along the vicinity of the transparent window surface outside the no-entry zone, and a person illuminated by the infrared rays is photographed by the black-and-white surveillance camera, and the presence or absence of the photographed person is detected by image processing, and if it is determined that the person has been stationary for a predetermined period of time, the person is determined to be an intruder. Patent document 3 also describes how feature information is acquired from video captured by a camera as security identification information, and this feature information is used in area security authentication processing, and area security in a specified area is determined based on the feature information. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-259922 [Patent Document 2] Japanese Patent Application Publication No. 10-83487 [Patent Document 3] Japanese Patent Application Laid-Open No. 2010-198207 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of this disclosure is to provide an image processing device, an image processing method, and a recording medium that aim to improve upon the techniques described in prior art documents. [Means for solving the problem]

[0005] One aspect of the image processing device includes an image acquisition means for acquiring an image captured so that a light-emitting area that emits light in a dark place is included within the angle of view, a determination means for determining whether to switch the power consumption mode depending on the light-emitting state of the light-emitting area included in the image, and a switching means for switching the power consumption mode depending on the determination result of the determination means.

[0006] One aspect of the image processing method involves acquiring an image captured so that a light-emitting area that emits light in a dark place is included within the angle of view, determining whether to switch the power consumption mode depending on the light-emitting state of the light-emitting area included in the image, and switching the power consumption mode depending on the result of the determination.

[0007] One aspect of the recording medium has a computer program recorded thereon to cause a computer to execute an image processing method that acquires an image captured so that a light-emitting area that emits light in a dark place is included within the angle of view, determines whether to switch the power consumption mode depending on the light-emitting state of the light-emitting area included in the image, and switches the power consumption mode depending on the result of the determination. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing the configuration of a face authentication device according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram of an unlocking system according to the second embodiment. [Figure 3]FIG. 3 is a schematic diagram of an image acquired by the face authentication device in the second embodiment. [Figure 4] FIG. 4 is a block diagram showing the configuration of a face authentication device according to the second embodiment. [Figure 5] FIG. 5 is a conceptual diagram of the determination operation performed by the face authentication device in the second embodiment. [Figure 6] FIG. 6 is a flowchart showing the flow of the power saving operation and face authentication operation performed by the face authentication device in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of an authentication device, an authentication method, and a recording medium will be described with reference to the drawings. [1: First embodiment]

[0010] An image processing device, an image processing method, and a recording medium according to a first embodiment will be described below. The image processing device, the image processing method, and the recording medium according to the first embodiment will be described below using an image processing device 1000 to which the image processing device, the image processing method, and the recording medium according to the first embodiment are applied. [1-1: Configuration of image processing device 1000]

[0011] The configuration of an image processing device 1000 in the first embodiment will be described with reference to Fig. 1. Fig. 1 is a block diagram showing the configuration of the image processing device 1000 in the first embodiment.

[0012] As shown in Fig. 1, image processing device 1000 includes image acquisition unit 1011, determination unit 1012, and switching unit 1013. Image acquisition unit 1011 acquires an image captured so that a light-emitting area that emits light in a dark place is included in the angle of view. Determination unit 1012 determines whether or not to switch the power consumption mode depending on the light-emitting state of the light-emitting area included in the image. Switching unit 1013 switches the power consumption mode depending on the determination result of determination unit 1012. [1-2: Technical Effects of the Image Processing Device 1000]

[0013] Image processing device 1000 in the first embodiment can switch power consumption modes according to the light emitting state of a light emitting area included in an image captured so that the light emitting area that emits light in a dark place is included in the angle of view. In other words, image processing device 1000 can change power consumption by providing a simple mechanism, the light emitting area, in the angle of view of the camera. [2: Second embodiment]

[0014] Hereinafter, embodiments of an image processing device, an image processing method, and a recording medium will be described with reference to the drawings. In the following, the embodiments of the image processing device, the image processing method, and the recording medium will be described using a face recognition device 10 as an image processing device to which the embodiments of the image processing device, the image processing method, and the recording medium are applied. [2-1: Overview of Unlocking System 1]

[0015] First, an overview of the unlocking system 1 according to this embodiment will be described. FIG. 2 is a schematic diagram of the unlocking system 1 according to this embodiment. The unlocking system 1 includes a door D, a face recognition device 10, an outdoor camera 20O, an indoor camera 20I, an outdoor switch SO, an indoor switch SI, a light L, and a fluorescent marker FM. The door D is provided at the entrance to a room 101, which is a partitioned space within a building, and closing the entrance may isolate the room 101 from the outside. When no person entering the room ENP or no person leaving the room EXP is present, the door D may be locked, isolating the room 101 from the outside. When the door D is unlocked, the person entering the room ENP and the person leaving the room EXP may be able to move between the room 101 and the outside. The face recognition device 10 may control the unlocking and locking of the door D.

[0016] An indoor camera 20I for acquiring an image to be used for facial recognition may be provided above near the door D on the indoor 101 side. The indoor camera 20I may acquire a facial image of a person leaving the room EXP. Furthermore, an outdoor camera 20O for acquiring an image to be used for facial recognition may be provided above near the door D outside the room 101. The outdoor camera 20O may acquire a facial image of a person entering the room ENP.

[0017] The facial recognition device 10 may authenticate the entering person ENP and the leaving person EXP. The facial recognition device 10 may perform facial recognition using facial images of the entering person ENP and the leaving person EXP. The facial recognition device 10 may perform facial recognition using a facial image of the entering person ENP captured by the outdoor camera 20O or a facial image of the leaving person EXP captured by the indoor camera 20I. The facial recognition device 10 may acquire an image from the outdoor camera 20O when the entering person ENP enters the room 101, and may acquire an image from the indoor camera 20I when the leaving person EXP leaves the room 101. The facial recognition device 10 may perform facial recognition processing using the acquired image, and if facial recognition is successful, may unlock the door D, allowing the entering person ENP and the leaving person EXP to move between the room 101 and the outside.

[0018] A light L may be provided on the ceiling of the room 101. An indoor switch SI may be provided on a wall near the door D inside the room 101. An outdoor switch SO may be provided on a wall outside the room 101 near the door D. The outdoor switch SO and the indoor switch SI may be instruction input mechanisms for switching the light L between on and off. For example, a person entering the room ENP may turn on the light L by operating the outdoor switch SO. A person leaving the room EXP may turn off the light L by operating the indoor switch SI. [2-2: Overview of Image I used for face recognition and power-saving operations]

[0019] An overview of the image I used in the face recognition operation and power saving operation in this embodiment will be described using Fig. 3. Fig. 3 shows the image I used in the face recognition operation and power saving operation in this embodiment. The image I may be an image captured by the indoor camera 20I. When there is an exiting person EXP about to leave the room 101, the indoor camera 20I may capture the image I so that it includes at least the face of the exiting person EXP.

[0020] 3, the indoor camera 20I captures the image I so that the fluorescent marker FM, which is a light-emitting region that emits light in a dark place, is included in the angle of view. The horizontal width of the fluorescent marker FM may occupy a predetermined percentage or more of the horizontal width of the image I.

[0021] The fluorescent markers FM may be provided in a certain area, such as on a wall of the room 101, so as to be within the imaging range of the indoor camera 20I. The fluorescent markers FM may be provided by applying fluorescent paint containing a persistent fluorescent material to an area included in the angle of view of the indoor camera 20I. The fluorescent markers FM may be provided by attaching fluorescent stickers to an area included in the angle of view of the indoor camera 20I. As shown in FIG. 3, the fluorescent markers FM may be provided so as to appear in a horizontal line at a height near the center of the image captured by the indoor camera 20I. The fluorescent markers FM may be provided so that the leaving person EXP to be authenticated appears in the center of the fluorescent markers FM within the angle of view of the indoor camera 20I. [2-3: Configuration of face recognition device 10]

[0022] The configuration of the face authentication device 10 in this embodiment will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the configuration of the face authentication device 10 in this embodiment.

[0023] 3, the face authentication device 10 includes a calculation device 11 and a storage device 12. The face authentication device 10 may further include a communication device 13, an input device 14, and an output device 15. However, the face authentication device 10 does not necessarily include at least one of the communication device 13, the input device 14, and the output device 15. The calculation device 11, the storage device 12, the communication device 13, the input device 14, and the output device 15 may be connected via a data bus 16.

[0024] The arithmetic device 11 includes, for example, at least one of a central processing unit (CPU), a graphics processing unit (GPU), and a field programmable gate array (FPGA). The arithmetic device 11 reads a computer program. For example, the arithmetic device 11 may read a computer program stored in the storage device 12. For example, the arithmetic device 11 may read a computer program stored in a computer-readable, non-transitory recording medium using a recording medium reading device (e.g., an input device 14, described later) not shown in the drawings that is included in the face authentication device 10. The arithmetic device 11 may acquire (i.e., download or read) the computer program from a device (not shown) located outside the face authentication device 10 via the communication device 13 (or another communication device). The arithmetic device 11 executes the read computer program. As a result, logical functional blocks for executing operations to be performed by the face authentication device 10 are realized within the arithmetic device 11. That is, the arithmetic device 11 can function as a controller for realizing logical functional blocks for executing the operations (in other words, processing) that the face authentication device 10 should perform.

[0025] Fig. 3 shows an example of logical functional blocks implemented in the computing device 11 for executing face authentication operation and power saving operation. As shown in Fig. 3, implemented in the computing device 11 are an image acquisition unit 111 which is a specific example of "image acquisition means", a determination unit 112 which is a specific example of "determination means", a switching unit 113 which is a specific example of "switching means", and an authentication unit 114 which is a specific example of "authentication means". The determination unit 112 may include an emission state determination unit 1121 which determines the emission state.

[0026] The details of the operations of the image acquisition unit 111, the determination unit 112, the switching unit 113, and the authentication unit 114 will be described later with reference to Fig. 6. However, the calculation device 11 does not necessarily have to include the authentication unit 114.

[0027] The storage device 12 can store desired data. For example, the storage device 12 may temporarily store a computer program executed by the arithmetic device 11. The storage device 12 may temporarily store data that the arithmetic device 11 temporarily uses when the arithmetic device 11 is executing a computer program. The storage device 12 may store data that the face recognition device 10 stores long-term. The storage device 12 may include at least one of a random access memory (RAM), a read-only memory (ROM), a hard disk device, a magneto-optical disk device, a solid-state drive (SSD), and a disk array device. In other words, the storage device 12 may include a non-transitory recording medium. The storage device 12 may store a master image MI used in the authentication operation by the authentication unit 114.

[0028] The communication device 13 is capable of communicating with devices external to the face authentication device 10 via a communication network (not shown). The communication device 13 may be capable of communicating with the indoor camera 20I, the outdoor camera 20O, and the door D.

[0029] The input device 14 is a device that accepts information input to the face authentication device 10 from outside the face authentication device 10. For example, the input device 14 may include an operation device (for example, at least one of a keyboard, a mouse, and a touch panel) that can be operated by an operator of the face authentication device 10. For example, the input device 14 may include a reading device that can read information recorded as data on a recording medium that can be externally attached to the face authentication device 10.

[0030] The output device 15 is a device that outputs information to the outside of the face recognition device 10. For example, the output device 15 may output information as an image. That is, the output device 15 may include a display device (a so-called display) that can display an image showing the information to be output. For example, the output device 15 may output information as sound. That is, the output device 15 may include an audio device (a so-called speaker) that can output sound. For example, the output device 15 may output information on paper. That is, the output device 15 may include a printing device (a so-called printer) that can print desired information on paper. [2-4: Overview of Determination Operation of Determining Unit 112]

[0031] 5 is an example of image I used in the determination operation by determination unit 112. Also, the following [Table 1] shows the power consumption modes corresponding to the state of room 101. [Table 1] TIFF0007736087000001.tif30169

[0032] The determination unit 112 determines whether or not facial recognition processing is necessary based on the light emission state of the fluorescent marker FM. FIG. 5(a) shows image Ia when the light L is on. Because the light L is on and the place is bright, the fluorescent marker FM reflected in image Ia is not emitting light. Therefore, the proportion of the fluorescent marker FM in the fluorescent region FR reflected in image Ia is 0%. The fluorescent region FR is the region in image Ia that includes the fluorescent marker FM. As shown in the left column of Table 1, when the state of room 101 is that of light L on, this can be considered to be a case where a person is present in room 101, in which case the power consumption mode may remain in the first mode, the camera frame rate may be relatively high, and the facial recognition operation by authentication unit 114 may continue.

[0033] FIG. 5(b) shows image Ib when the light L is off. Because the light L is off and it is a dark place, the fluorescent markers FM appearing in image Ib emit light. Furthermore, the leaving person EXP is leaving the room, and the leaving person EXP appears in image Ib. Therefore, the proportion of the fluorescent markers FM in the fluorescent region FR appearing in image Ib is less than the first threshold. The first threshold may be, for example, 25%. As shown in the middle column of Table 1, when the state of room 101 is such that the light L is off and the leaving person EXP appears in image I, it can be considered that an authentication operation for the leaving person EXP is required, in which case the power consumption mode may remain in the first mode, the camera frame rate may be relatively high, and the face authentication operation by authentication unit 114 may continue.

[0034] FIG. 5(c) shows image Ic when the light L is off. Because the light L is off and it is a dark place, the fluorescent markers FM appearing in image Ic are emitting light. Furthermore, because there is no leaving person EXP, the leaving person EXP is not captured in image Ic. Therefore, the proportion of the fluorescent markers FM in the fluorescent region FR captured in image Ic is equal to or greater than the first threshold. The first threshold may be, for example, 25%. As shown in the right column of Table 1, when the state of room 101 is such that the light L is off and the leaving person EXP is not captured in image I, it can be considered that authentication operation for the leaving person EXP is unnecessary, and the power consumption mode may be switched to the second mode, the camera frame rate may be switched to a relatively low value, and the face authentication operation by authentication unit 114 may be stopped.

[0035] Furthermore, the determination unit 112 may determine whether authentication processing is necessary based on the illuminated area in the fluorescent region FR. The determination unit 112 may determine whether authentication processing is necessary based on the proportion of the area in the fluorescent region FR that is brighter than its surroundings. For example, when the light L is on, the fluorescent region FR is uniformly bright, so the area brighter than its surroundings is 0%. For example, when the light L is off and there is nothing blocking the path between the indoor camera 20I and the fluorescent marker FM, the area of ​​the fluorescent marker FM included in the fluorescent region FR is brighter than its surroundings. For example, when the light L is off and there is something blocking the path between the indoor camera 20I and the fluorescent marker FM, such as a leaving person EXP, part of the area of ​​the fluorescent marker FM included in the fluorescent region FR is blocked by the leaving person EXP, and the proportion of the area brighter than its surroundings is smaller than when there is no leaving person EXP.

[0036] The first threshold value, for example 25% mentioned above, can be determined according to the proportion of the fluorescent marker FM that is hidden when a person stands in front of the indoor camera 20I. The first threshold value may be any value that is adjusted according to the conditions of the room 101, the range that can be captured within the angle of view of the indoor camera 20I, and the range in which the fluorescent marker FM is provided. [2-5: Power-saving operation and face authentication operation performed by face authentication device 10]

[0037] The power saving operation and authentication operation performed by the face authentication device 10 in this embodiment will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the flow of the power saving operation and authentication operation performed by the face authentication device 10 in this embodiment. The flowchart shown in Fig. 6 shows the operation performed for each frame.

[0038] 6, an image I is captured so that the fluorescent marker FM is included in the angle of view (step S10). The image acquisition unit 111 acquires the image I captured so that the fluorescent marker FM is included in the angle of view (step S11). The image acquired by the image acquisition unit 111 may be used by the determination unit 112 to determine whether or not a person is present in the room before the authentication unit 114 performs face recognition processing.

[0039] The determination unit 112 determines whether to switch the power consumption mode depending on the light emission state of the fluorescent markers FM included in image I (step S12). The light emission state determination unit 1121 may determine whether the size of the fluorescent markers FM included in image I is equal to or greater than a first threshold or less than a second threshold. The light emission state determination unit 1121 may also determine whether the proportion of the fluorescent markers FM included in image I is equal to or greater than a first threshold or less than a second threshold. That is, the light emission state determination unit 1121 may determine the light emission state based on the relative size of the fluorescent markers FM with respect to image I. The light emission state determination unit 1121 may also determine whether the number of pixels of the image of the fluorescent markers FM included in image I is equal to or greater than a first threshold or less than a second threshold. That is, the light emission state determination unit 1121 may determine the light emission state based on the absolute size of the fluorescent markers FM. As shown in FIG. 5, the determination unit 1122 may determine whether the proportion of the fluorescent markers FM in the fluorescent region FR included in image I is equal to or greater than a first threshold or less than a second threshold. Because the determination process has a relatively light load compared to the authentication process, the determination unit 112 may perform the determination process prior to the face authentication process by the authentication unit 114. The determination unit 112 may determine the presence or absence of a person in the room 101 based on the light emission state of the fluorescent markers FM included in the image I. For example, if the fluorescent markers FM included in the fluorescent region FR are equal to or greater than a first threshold, the determination unit 112 may determine that no person is present in the room 101. The determination unit 112 may also determine whether the light L is on or off based on the light emission state of the fluorescent markers FM. Furthermore, the determination unit 112 may detect an operation of the indoor switch SI by a leaving person EXP or an operation of the outdoor switch SO by a entering person ENP, and determine whether the light L is on or off. If the proportion of the fluorescent markers FM included in the image I is equal to or greater than a first threshold, the determination unit 112 may determine to switch the power consumption mode from the first mode to a second mode that consumes less power than the first mode.

[0040] If the proportion of fluorescent markers FM is equal to or greater than the first threshold (step S12: ≧first threshold), the switching unit 113 determines whether the power consumption mode is the first mode and whether the period during which the proportion of fluorescent markers FM is equal to or greater than the first threshold is equal to or greater than a predetermined period (step S13). If the power consumption mode is the first mode and the period during which the proportion of fluorescent markers FM is equal to or greater than the first threshold is equal to or greater than the predetermined period (step S13: Yes), the switching unit 113 switches the power consumption mode (step S14). The switching unit 113 may switch the power consumption mode from the first mode to the second mode. In the second mode, the switching unit 113 may stop the face recognition operation by the authentication unit 114. In other words, if the determination unit 112 determines that the light L is off and the room 101 is unoccupied, the face recognition process by the authentication unit 114 may be omitted. As a result, high-load face recognition process is not performed, and power consumption is reduced, thereby achieving power savings. The camera frame rate in the second mode may be lower than the camera frame rate in the first mode. That is, if the determination unit 112 determines that the light L is off and the room 101 is unoccupied, the camera frame rate may be lowered. This reduces power consumption in the unlocking system 1, thereby achieving energy savings. Lowering the camera frame rate may result in images being acquired before and after the entry person ENP and the exit person EXP pass by, potentially resulting in the entry person ENP and the exit person EXP being overlooked. Therefore, the frame rate lower limit may be set based on the camera's field of view and the movement speed of the entry person ENP and the exit person EXP. The frame rate lower limit may also be set based on the length of the fluorescent marker within the camera's field of view and the movement speed of the entry person ENP and the exit person EXP. The frame rate lower limit may also be set based on the average movement speed of the entry person ENP and the exit person EXP.

[0041] On the other hand, if the proportion of the fluorescent markers FM is less than the second threshold (step S12:<second threshold), the switching unit 113 determines whether the power consumption mode is the second mode (step S15). If the power consumption mode is the second mode (step S15: Yes), the switching unit 113 switches the power consumption mode (step S16). The switching unit 113 may switch the power consumption mode from the second mode to the first mode. The frame rate of the camera in the first mode may be higher than the frame rate of the camera in the second mode. The frame rate of the camera in the first mode may be a frame rate suitable for face recognition processing. When switching the power consumption mode to the first mode, the switching unit 113 may start a face recognition operation by the authentication unit 114. The second threshold may be the same as or different from the first threshold and may be determined depending on the environment. The second threshold may be, for example, 25%.

[0042] The authentication unit 114 performs face authentication using a face image included in the angle of view of the image I. The authentication unit 114 may perform face detection processing, feature extraction processing, and matching processing with a master image MI registered in the storage device 12. If the authentication by the authentication unit 114 is successful (step S17: Yes), the face authentication device 10 unlocks the door D (step S18). The face authentication device 10 may send a control signal via the communication device 13 to instruct the door D to unlock the door. Furthermore, the face authentication device 10 may send a control signal to instruct the door D to lock the door D after a predetermined time has elapsed. On the other hand, if the authentication by the authentication unit 114 fails (step S17: No), the face authentication device 10 does not unlock the door D, and the door D remains locked.

[0043] The face recognition device 10 in this embodiment may be applied mainly to the case of authenticating an exiting person EXP leaving the room 101. In other words, the authentication process for the entering person ENP may be performed at all times, and the outdoor camera 20O may be always running. When all people have left the room 101 and the lights in the room have been turned off, the face recognition device 10 may detect that the lights in the room have been turned off and determine that no person is present. If no person is present, the face recognition device 10 may stop its authentication process to reduce power consumption of the unlocking system 1. Furthermore, since the light L is turned on when the entering person ENP enters the room, the face recognition device 10 may resume the face recognition process by the authentication unit 114.

[0044] The light-emitting area may emit light when the light source L is off. The light-emitting area may be formed by applying fluorescent paint containing a fluorescent substance, attaching a fluorescent sticker, or by using, for example, a fluorescent lamp that stores light. While the above embodiment illustrates an example in which the fluorescent marker FM is drawn as a horizontal line on the wall, the fluorescent marker FM may be provided in any manner that can determine whether a person is present within the camera's field of view. For example, multiple fluorescent stickers may be provided as the light-emitting area so that at least a portion of the light-emitting area is hidden when a person is present within the camera's field of view. The determination unit 112 may determine whether the fluorescent marker FM or the fluorescent sticker is obscured by a person based on whether the fluorescent marker FM or the fluorescent sticker is divided. The determination unit 112 may determine that a person is present when the horizontal length of the fluorescent marker FM or the fluorescent sticker changes, since the fluorescent marker FM or the fluorescent sticker is hidden.

[0045] Furthermore, determination unit 112 may compare the proportion of luminous areas with a third threshold different from the first threshold, and the power mode may have a third mode. That is, determination unit 112 may determine to switch the power consumption mode from the first mode to the third mode when the proportion of luminous areas included in the image is equal to or greater than the third threshold, and the switching unit may switch the power consumption mode from the first mode to the third mode. In this case, for example, (1) the frame rate of the camera in the first mode may be higher than the frame rate of the camera in the second mode, and the face authentication operation by authentication unit 114 may be stopped in the third mode, or (2) the frame rate of the camera in the first mode may be higher than the frame rate of the camera in the third mode, and the face authentication operation by authentication unit 114 may be stopped in the second mode. That is, the timing of changing the frame rate of the camera may differ from the timing of stopping the face authentication operation by authentication unit 114. [2-5: Technical Effects of Facial Recognition Device 10]

[0046] The face recognition device 10 of this embodiment can switch power consumption modes depending on the luminous state of a luminous area included in an image captured so that the luminous area that emits light in a dark place is included in the angle of view. That is, the face recognition device 10 can change power consumption by providing a simple mechanism, a luminous area, in the angle of view of the camera. Furthermore, when the proportion of the luminous area included in the image is equal to or greater than a first threshold, the face recognition device 10 of this embodiment switches the power consumption mode from the first mode to a second mode that consumes less power, thereby realizing suppression of power consumption.

[0047] The face recognition device 10 of this embodiment uses fluorescent markers FM as light-emitting regions, and is therefore comparatively inexpensive and easy to install compared to using a motion sensor such as an infrared sensor, and is therefore advantageous in terms of cost. When a motion sensor or the like is introduced, introduction costs such as the cost of purchasing the sensor and the cost of installation are incurred. Furthermore, if a method for determining whether or not a person is present in the room 101 is adopted that counts the number of people in the room, such as incrementing the count by 1 when a person enters the room and decrementing the count by 1 when a person leaves the room, it will be impossible to accurately grasp the presence status in the room if a person authenticated at the time of entry is accompanied by another person who enters the room at the same time. In contrast, the face recognition device 10 of this embodiment can accurately grasp whether or not there is a person EXP who wants to leave the room 101, even if there is a person accompanied by another person.

[0048] Authentication for entering and exiting the room 101 is used for both entering and exiting the room. However, particularly when exiting the room 101, authentication processing is often ongoing even when all people have left the room 101 and the light L is off. However, authentication processing within the room 101 is unnecessary at least when no one is present in the room 101. Therefore, the face recognition device 10 of this embodiment can suspend face recognition processing while no one is present in the room 101 and the light L is off, thereby reducing power consumption. Image processing requires a lighter processing load than face recognition processing. Therefore, the face recognition device 10 determines the presence of a person wishing to enter or exit the room 101 through image processing, and if it determines that the person is not present, suspends face recognition processing. Since face recognition processing requires a heavier processing load than image processing, suspending authentication processing reduces the processing load on the system. In other words, the power consumed by the unlocking system 1 can be reduced. In addition, if the frequency of the need to authenticate the person leaving the room EXP decreases, the camera frame rate can be lowered, further reducing power consumption. On the other hand, since facial recognition starts only when it becomes necessary, it can prevent inconvenience to users.

[0049] On the other hand, frequent switching of the power mode may result in high power consumption. According to the face recognition device 10 of this embodiment, when the lights are off and a period in which no leaving person EXP is present within the angle of view continues for a predetermined period of time, the power mode is switched, thereby preventing high power consumption.

[0050] Furthermore, since the horizontal width of the light-emitting area employed by the face recognition device 10 in this embodiment occupies a predetermined percentage or more of the horizontal width of the image, it is possible to accurately determine that a person EXP has entered the field of view when the lights are off.

[0051] In the above embodiment, the face recognition device 10 as an image processing device is described as having the authentication unit 114, but the mechanism for performing the face recognition operation may be provided in a device external to the image processing device. That is, the switching unit 113 may switch the operation mode of the mechanism for performing the external authentication operation by sending a switching signal via the communication device 13. [3: Note]

[0052] The following additional notes are provided regarding the above-described embodiment. [Appendix 1] an image acquisition means for acquiring an image captured so that a light-emitting region that emits light in a dark place is included within an angle of view; a determination means for determining whether to switch a power consumption mode in accordance with the light emitting state of the light emitting area included in the image; a switching means for switching the power consumption mode in accordance with the determination result of the determining means; An image processing device comprising: [Appendix 2] the determining means determines to switch the power consumption mode from a first mode to a second mode that consumes less power than the first mode when a proportion of the light emitting region included in the image is equal to or greater than a first threshold; The switching means switches the power consumption mode from the first mode to the second mode in accordance with the determination result of the determination means. 2. The image processing device according to claim 1. [Appendix 3] the image acquisition means acquires the image from a camera that generates the image by capturing an image of an imaging target area so that the light-emitting area is included in an angle of view; The frame rate of the camera in the first mode is higher than the frame rate of the camera in the second mode. 3. The image processing device according to claim 2. [Appendix 4] Further, an authentication means for performing a face authentication operation using a face image included in the image is provided, The switching means stops the face authentication operation by the authentication means in the second mode. 4. The image processing device according to claim 2 or 3. [Appendix 5] When the ratio is less than a second threshold, the determining means determines that the power consumption mode should be switched from the second mode to the first mode; The switching means starts the face authentication operation by the authentication means when the power consumption mode is switched to the first mode. 5. The image processing device according to claim 4. [Appendix 6] The determining means determines to switch from the first mode to the second mode when the period during which the ratio is equal to or greater than the first threshold continues for a predetermined period or longer. 6. The image processing device according to any one of appendices 2 to 5. [Appendix 7] The horizontal width of the light emitting area occupies a predetermined percentage or more of the horizontal width of the image. 7. The image processing device according to any one of appendices 1 to 6. [Appendix 8] Acquire an image captured so that a luminous region that emits light in a dark place is included within the angle of view; determining whether to switch a power consumption mode according to a light emitting state of the light emitting area included in the image; Switching the power consumption mode depending on the result of the determination. Image processing methods. [Appendix 9] On the computer, Acquire an image captured so that a luminous region that emits light in a dark place is included within the angle of view; determining whether to switch a power consumption mode according to a light emitting state of the light emitting area included in the image; Switching the power consumption mode depending on the result of the determination. A recording medium on which a computer program for executing an image processing method is recorded.

[0053] At least some of the constituent elements of each of the above-described embodiments can be appropriately combined with at least some of the other constituent elements of each of the above-described embodiments. Some of the constituent elements of each of the above-described embodiments may not be used. Furthermore, to the extent permitted by law, the disclosures of all documents (e.g., published patent applications) cited in this disclosure are incorporated by reference as part of the description of this disclosure.

[0054] This disclosure may be modified as appropriate within the scope of the claims and the technical idea that can be read from the entire specification. Image processing devices, power saving methods, and recording media that incorporate such modifications are also included in the technical idea of ​​this disclosure. [Explanation of symbols]

[0055] 1. Unlocking system 1000 Image Processing Device 10 Facial Recognition Device 1011,111 Image acquisition unit 1012,112 Judgment part 1013,113 Switching section 114 Authentication Department ENP entrant EXP Leaver 20O Outdoor Camera 20I Indoor Camera D Door SO Outdoor switch SI indoor switch L lighting 101 Indoor FM fluorescent marker FR Fluorescent region I Image

Claims

1. an image acquisition means for acquiring an image captured so that a light-emitting region that emits light in a dark place is included within an angle of view; a determination means for determining whether to switch a power consumption mode in accordance with the light emitting state of the light emitting area included in the image; a switching means for switching the power consumption mode in accordance with the determination result of the determining means; An image processing device comprising:

2. When the size of the light emitting region included in the image is equal to or larger than a first threshold, the determination means determining that the power consumption mode should be switched from a first mode to a second mode in which power consumption is less than that in the first mode; The switching means switches the power consumption mode from the first mode to the second mode in accordance with the determination result of the determination means. The image processing device according to claim 1 .

3. the image acquisition means acquires the image from a camera that generates the image by capturing an image of an imaging target area so that the light-emitting area is included in an angle of view; The frame rate of the camera in the first mode is higher than the frame rate of the camera in the second mode. The image processing device according to claim 2 .

4. Further, an authentication means for performing a face authentication operation using a face image included in the image is provided, The switching means stops the face authentication operation by the authentication means in the second mode.

4. The image processing device according to claim 2 or 3.

5. When the magnitude is less than a second threshold, the determining means determines that the power consumption mode should be switched from the second mode to the first mode; The switching means starts the face authentication operation by the authentication means when the power consumption mode is switched to the first mode. The image processing device according to claim 4 .

6. The determining means determines to switch from the first mode to the second mode when the period during which the magnitude is equal to or greater than the first threshold continues for a predetermined period or longer.

4. The image processing device according to claim 2 or 3.

7. The horizontal width of the light emitting area occupies a predetermined percentage or more of the horizontal width of the image. The image processing device according to any one of claims 1 to 3.

8. A computer-implemented image processing method, comprising: Acquire an image captured so that a luminous region that emits light in a dark place is included within the angle of view; determining whether to switch a power consumption mode according to a light emitting state of the light emitting area included in the image; Switching the power consumption mode depending on the result of the determination. Image processing methods.

9. On the computer, Acquire an image captured so that a luminous region that emits light in a dark place is included within the angle of view; determining whether to switch a power consumption mode according to a light emitting state of the light emitting area included in the image; Switching the power consumption mode depending on the result of the determination. A computer program for executing an image processing method.

Images