Information processing system, information processing method, and recording medium

Abstract

This information processing system (10) comprises: an acquisition means (110) which acquires a first image and a second image that are captured in such a manner that the optical axes cross at a prescribed point; a determination means (120) which determines whether the difference between subject positions in the first image and the second image is within a prescribed range; and a control means (130) which controls to capture an iris image of the subject when the difference is within the prescribed range. According to this information processing system, the iris image of the subject can be captured at a suitable timing.

Description

Technical Field

[0001] This disclosure relates to the technical fields of information processing systems, information processing methods, and recording media.

Background Art

[0002] As this type of system, there is known one that detects the position of a subject and starts imaging an iris image. For example, in Patent Document 1, a technique is disclosed in which a distance measuring sensor is used to detect that a subject has entered a predetermined distance range, and imaging is started when the subject enters the predetermined distance range.

[0003] As other related techniques, in Patent Document 2, it is disclosed that a stereoscopic image is obtained based on images taken from a plurality of different viewpoints. In Patent Document 3, it is disclosed that an image is taken when the corneal apex of an eye to be examined coincides with the intersection of the optical axes of an illumination optical system and a photographing optical system. In Patent Document 4, it is disclosed that an object existing at the intersection of the optical axes of Camera A and Camera B is displayed on a screen.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] This disclosure aims to improve the techniques disclosed in the prior art documents.

Means for Solving the Problems

[0006] One aspect of the information processing system disclosed herein includes: acquisition means for acquiring a first image and a second image captured such that the optical axes intersect at a predetermined point; determination means for determining whether the difference between the position of an object in the first image and the position of the object in the second image is within a predetermined range; and control means for controlling the system to capture an iris image of the object if the difference is within the predetermined range.

[0007] One aspect of the information processing method of this disclosure involves acquiring a first image and a second image, both captured so that the optical axes intersect at a predetermined point, using at least one computer; determining whether the difference between the position of an object in the first image and the position of the object in the second image is within a predetermined range; and controlling the computer to capture an iris image of the object if the difference is within the predetermined range.

[0008] One aspect of the recording medium of this disclosure includes a computer program that causes at least one computer to execute an information processing method, which involves acquiring a first image and a second image captured so that the optical axes intersect at a predetermined point, determining whether the difference between the position of an object in the first image and the position of the object in the second image is within a predetermined range, and controlling the computer to capture an iris image of the object if the difference is within the predetermined range. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram showing the hardware configuration of the information processing system according to the first embodiment. [Figure 2] This is a block diagram showing the functional configuration of the information processing system according to the first embodiment. [Figure 3] This is a top view showing the optical axis of the camera in the information processing system according to the first embodiment. [Figure 4] This is a plan view showing examples of the first and second images acquired by the information processing system according to the first embodiment. [Figure 5]This is a flowchart showing the operation flow of the information processing system according to the first embodiment. [Figure 6] This is a flowchart showing the operation flow of the information processing system according to the second embodiment. [Figure 7] This is a plan view showing an example of the first and second images acquired by the information processing system according to the third embodiment. [Figure 8] This is a top view showing the trigger position and focus position in the information processing system according to the fourth embodiment. [Figure 9] This is a flowchart showing the operation flow of the information processing system according to the fourth embodiment. [Figure 10] This is a block diagram showing the functional configuration of the information processing system according to the fifth embodiment. [Figure 11] This is a flowchart showing the operation flow of the information processing system according to the fifth embodiment. [Figure 12] This block diagram shows the functional configuration of the information processing system according to the sixth embodiment. [Figure 13] This is a top view showing an example of the arrangement of the first camera, second camera, and third camera in the information processing system according to the seventh embodiment. [Figure 14] This is a top view showing an example of the arrangement of the first camera, second camera, and third camera in the information processing system according to the eighth embodiment. [Figure 15] This is a front view showing an example of the arrangement of the fourth camera and mirror in the information processing system according to the ninth embodiment. [Figure 16] This is a plan view showing examples of the first and second images acquired by the information processing system according to the ninth embodiment. [Figure 17] This is a top view showing an example of the arrangement of the fifth camera and mirror in the information processing system according to the tenth embodiment. [Figure 18] This is a plan view showing examples of the first and second images acquired by the information processing system according to the 10th embodiment. [Figure 19] This is a block diagram showing the functional configuration of the information processing system according to the 11th embodiment. [Figure 20] It is a flowchart showing the operation flow of the information processing system according to the 11th embodiment. [Figure 21] It is a flowchart showing the operation flow of the information processing system according to the 12th embodiment. [Figure 22] It is a flowchart showing the operation flow of the information processing system according to the 13th embodiment. [Figure 23] It is a flowchart showing the operation flow of the information processing system according to the 14th embodiment. [Figure 24] It is a plan view showing an example of the first image and the second image acquired by the information processing system according to the 14th embodiment, and its search area.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of an information processing system, an information processing method, and a recording medium will be described while referring to the drawings.

[0011] <First Embodiment> The information processing system according to the first embodiment will be described with reference to FIGS. 1 to 5.

[0012] (Hardware Configuration) First, the hardware configuration of the information processing system according to the first embodiment will be described while referring to FIG. 1. FIG. 1 is a block diagram showing the hardware configuration of the information processing system according to the first embodiment.

[0013] As shown in Figure 1, the information processing system 10 according to the first embodiment includes a processor 11, RAM (Random Access Memory) 12, 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 information processing system 10 also includes a camera 18. The processor 11, RAM 12, ROM 13, storage device 14, input device 15, output device 16, and camera 18 are connected via a data bus 17.

[0014] 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, ROM 13, and 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 also obtain (i.e., read) a computer program from a device (not shown) located outside the information processing system 10 via a network interface. The processor 11 controls the RAM 12, storage device 14, input device 15, and output device 16 by executing the read computer program. In this embodiment in particular, when the processor 11 executes the read computer program, a functional block that performs processing for capturing the target image is realized within the processor 11. That is, the processor 11 may function as a controller that performs each control in the information processing system 10.

[0015] 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 (Demand-Side Platform), or an ASIC (Application Specific Integrated Circuit). The processor 11 may consist of one of these, or it may be configured to use multiple of them in parallel.

[0016] RAM12 temporarily stores computer programs executed by processor 11. RAM12 also temporarily stores data that processor 11 uses temporarily while executing computer programs. RAM12 may be, for example, D-RAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory). Alternatively, other types of volatile memory may be used instead of RAM12.

[0017] ROM 13 stores computer programs executed by processor 11. ROM 13 may also store other static data. ROM 13 may be, for example, P-ROM (Programmable Read Only Memory) or EPROM (Erasable Read Only Memory). Alternatively, other types of non-volatile memory may be used instead of ROM 13.

[0018] The storage device 14 stores data that the information processing system 10 will save for the long term. The storage device 14 may also operate as a temporary storage device for the processor 11. The storage device 14 may include, for example, at least one of a hard disk drive, a magneto-optical disk drive, an SSD (Solid State Drive), and a disk array device.

[0019] The input device 15 is a device that receives input instructions from the 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 a mobile terminal such as a smartphone or tablet. The input device 15 may also be a device capable of voice input, for example, including a microphone.

[0020] 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) capable of displaying information related to the information processing system 10. Alternatively, the output device 16 may be a speaker or the like capable of outputting information related to the information processing system 10 as sound. The output device 16 may be configured as a mobile terminal such as a smartphone or tablet. Furthermore, the output device 16 may be a device that outputs information in a format other than an image. For example, the output device 16 may be a speaker that outputs information related to the information processing system 10 as sound.

[0021] Camera 18 is a camera installed in a location where it can capture an image of the target. The target here is not limited to humans, but may include animals such as dogs, cats, snakes, and birds, as well as robots. Camera 18 may capture an image of the entire target, or it may capture an image of only a part of the target. Camera 18 may capture still images, or it may capture video. Camera 18 may be configured as a visible light camera, or as a near-infrared camera. Multiple cameras 18 may be provided. Multiple cameras 18 may be of the same type, or of different types. Camera 18 may have a function to automatically turn off its power when, for example, it is not capturing an image. In this case, components with shorter lifespans, such as liquid lenses and motors, may be prioritized for power-off. The specific configuration of camera 18 will be described in detail in other embodiments described later.

[0022] Although Figure 1 shows an example of an information processing system 10 comprising multiple devices, all or some of these functions may be implemented by a single device (imaging device). This imaging device may, for example, consist only of the processor 11, RAM 12, ROM 13, and imaging unit 18 described above, with other components (i.e., storage device 14, input device 15, output device 16) provided by, for example, external devices connected to the imaging device. Furthermore, the imaging device may implement some of its computational functions through external devices (e.g., external servers or cloud services).

[0023] (Functional configuration) Next, the functional configuration of the information processing system 10 according to the first embodiment will be described with reference to Figure 2. Figure 2 is a block diagram showing the functional configuration of the information processing system according to the first embodiment.

[0024] The information processing system 10 according to the first embodiment is configured as a system for capturing images of a target. More specifically, the information processing system 10 is configured to capture an iris image of a target. The use of the iris image captured by the information processing system 10 is not particularly limited, but it may be used for biometric authentication, for example. For example, the information processing system 10 may be configured as part of a system that captures images of a walking target and performs biometric authentication (a so-called walk-through authentication system).

[0025] As shown in Figure 2, the information processing system 10 according to the first embodiment is configured to include an acquisition unit 110, a determination unit 120, and a control unit 130 as components for realizing its functions. Each of the acquisition unit 110, the determination unit 120, and the control unit 130 may be a processing block realized by, for example, the processor 11 (see Figure 1) described above.

[0026] The acquisition unit 110 is configured to acquire a first image and a second image. The first image and the second image are images captured such that the optical axes of the optical systems that capture each image intersect at a predetermined point. The first image and the second image may be captured by the camera 18 (see Figure 1) described above. For example, the first image and the second image may be captured by two cameras 18 whose optical axes intersect with each other. Alternatively, the first image and the second image may be captured by a single camera 18 via a mirror or the like. A specific example of the arrangement of the camera 18 that captures the first image and the second image will be described in detail later.

[0027] The determination unit 120 is configured to perform a determination process using the first image and the second image acquired by the acquisition unit 110. Specifically, the determination unit 120 is configured to determine whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range. The "difference" here may be, for example, the distance (i.e., Euclidean distance) between the first coordinate indicating the position of the object in the first image and the coordinate indicating the position of the object in the second image, or it may be the degree of overlap between the first detection region indicating the position of the object in the first image and the second detection region indicating the position of the object in the second image (for example, (first detection region ∩ second detection region) / (first detection region ∪ second detection region). Therefore, the determination unit 120 may, for example, determine whether the distance between the first coordinate indicating the position of the object in the first image and the second coordinate indicating the position of the object in the second image is within a predetermined range. Alternatively, the determination unit 120 may determine whether the degree of overlap between the first detection region in the first image and the second detection region in the second image is within a predetermined range. The "predetermined range" here refers to the range in the first image. This threshold is set to determine whether there is a significant difference between the position of the target in the first image and the position of the target in the second image (in other words, whether the difference is within a predetermined threshold), and an appropriate value can be set in advance. The predetermined range can be set by a person, or the value can be adjusted through repeated learning. The determination unit 120 may perform a process to normalize the first image and the second image (i.e., adjust the scale) when calculating the difference. For example, the determination unit 120 may obtain the scale ratio between the first image and the second image in advance and perform the normalization process based on that scale ratio. Alternatively, the determination unit 120 may perform a process to normalize the first image and the second image using the internal parameters of the camera 18 that captures the first image and the second image (e.g., focus, pixel size information, etc.).

[0028] The control unit 130 is configured to control the imaging of the iris image of the target based on the determination result from the determination unit 120. Specifically, the control unit 130 may control the camera 18 to image the iris of the target when the determination unit determines that the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range. The camera 18 controlled here (i.e., the camera 18 that images the iris) may be different from the camera 18 that images the first and second images.

[0029] (Trigger detection) Next, with reference to Figures 3 and 4, the determination process using the first and second images by the determination unit 120 described above (hereinafter referred to as "trigger determination") will be specifically explained. Figure 3 is a top view showing the optical axis of the camera in the information processing system according to the first embodiment. Figure 4 is a plan view showing an example of the first and second images acquired by the information processing system according to the first embodiment.

[0030] In Figure 3, assume that the first camera 181 captures the first image and the second camera 182 captures the second image. In this case, the first camera 181 and the second camera 182 are positioned so that their respective optical axes intersect at a predetermined point. Hereafter, this predetermined point where the optical axes intersect will be referred to as the "trigger point."

[0031] As shown in Figure 4(a), when the object is located far from the trigger point as viewed from the first camera 181 and the second camera 182, a relatively large difference occurs between the position of the object in the first image and the position of the object in the second image. For example, in the first image, the object is captured near the left edge of the image, while in the second image, the object is captured near the right edge of the image. In this way, if the difference between the position of the object in the first image and the position of the object in the second image is large (i.e., outside the predetermined range), it can be determined that the object is located far from the trigger point.

[0032] On the other hand, as shown in Figure 4(b), when the object is present at the trigger point, the difference between the object's position in the first image and its position in the second image is relatively small. For example, in both the first and second images, the object is captured near the center of the image. Thus, when the difference between the object's position in the first image and its position in the second image is small (i.e., within a predetermined range), it can be determined that the object is present at the trigger point. For this reason, if the trigger point is set near the focus position of the camera 18 that captures the iris image, the iris image of the object can be captured at the appropriate timing.

[0033] (Flow of operations) Next, the operation flow of the information processing system 10 according to the first embodiment will be described with reference to Figure 5. Figure 5 is a flowchart showing the operation flow of the information processing system according to the first embodiment.

[0034] As shown in Figure 5, when the information processing system 10 according to the first embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). While it is preferable that the first image and the second image are typically captured simultaneously, some error may be tolerated. Alternatively, if the difference in the capture timing of the first and second images is known, a predetermined range may be set considering that difference. The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0035] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The position of the target may be detected as the position of a pre-set part, for example. For example, the determination unit 120 may detect the position of the target's eyes, nose, mouth, entire face, hands, feet, etc., as the position of the target. To give one example of detecting the position of the target's eyes as the position of the target, the determination unit 120 may detect the position of the right eye in the first image and the position of the right eye in the second image, or it may detect the position of the left eye in the first image and the position of the left eye in the second image, respectively. Alternatively, the determination unit 120 may detect the center coordinates of the right eye in the first image and the center coordinates of the right eye in the second image, respectively, or it may detect the center coordinates of the left eye in the first image and the center coordinates of the left eye in the second image, respectively. Alternatively, the determination unit 120 may detect the center coordinates (center point) of the right and left eyes in the first image, and the center coordinates of the right and left eyes in the second image, respectively. The above is an example of detecting the eyes, but when detecting other parts, the position of the target may be detected based on various points in a similar manner. Taking the case of detecting the position of the target's nose as one example, the determination unit 120 may detect the position of the nose in the first image and the position of the nose in the second image, respectively. Alternatively, the determination unit 120 may detect the center coordinates of the nose in the first image (for example, the center coordinates of the upper and lower ends of the nose, or the center coordinates of the right and left ends of the nose) and the center coordinates of the nose in the second image, respectively. Taking the case of detecting the position of the target's face as one example, the determination unit 120 may detect the position of the entire face in the first image and the position of the entire face in the second image, respectively. Alternatively, the determination unit 120 may detect the center coordinates of the entire face in the first image (for example, the center coordinates of the upper and lower ends of the entire face, or the center coordinates of the right and left ends of the entire face) and the center coordinates of the entire face in the second image. Alternatively, the determination unit 120 may detect multiple positions of the above-mentioned parts and use the center position of these multiple positions as the target position. For example, the determination unit 120 may detect the position of the right eye, the position of the left eye, and the position of the nose, and use the center position of the right eye, the left eye, and the nose as the target position.If no object is detected in at least one of the first and second images, the subsequent processing may be omitted, and processing may be resumed from step S101.

[0036] Next, the determination unit 120 determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130. If the difference between the position of the target in the first image and the position of the target in the second image is not within the predetermined range (step S103: NO), processing is resumed from step S101.

[0037] On the other hand, if the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range (step S103: YES), the control unit 130 controls the system to capture an iris image of the object (step S104). One iris image may be captured, or multiple images may be captured. The iris images may be captured as each frame of a video.

[0038] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the first embodiment will be described.

[0039] As explained in Figures 1 to 5, in the information processing system 10 according to the first embodiment, a trigger determination is made based on the first and second images, which are captured so that their optical axes intersect, and an iris image is captured according to the determination result. In this way, the position of the target can be identified and an iris image can be captured at the appropriate timing. This effect is particularly noticeable when using an iris camera with a relatively narrow focusing range. Furthermore, in this embodiment, since the trigger determination is made using the first and second images, it is not necessary to provide a separate sensor, such as one for detecting the position of the target. For example, it is conceivable to perform the trigger determination using a distance sensor or proximity sensor, but in this embodiment, these distance sensors and proximity sensors are unnecessary.

[0040] <Second Embodiment> The information processing system 10 according to the second embodiment will be described with reference to Figure 6. Note that the second embodiment differs from the first embodiment described above only in some operations; other parts may be identical to the first embodiment. Therefore, the following will describe in detail the parts that differ from the first embodiment already described, and will omit explanations of other overlapping parts as appropriate.

[0041] (Flow of operations) First, the operation flow of the information processing system 10 according to the second embodiment will be explained with reference to Figure 6. Figure 6 is a flowchart showing the operation flow of the information processing system according to the second embodiment. Note that in Figure 6, the same reference numerals are used for the same processes as shown in Figure 5.

[0042] As shown in Figure 6, when the information processing system 10 according to the first embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0043] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The determination unit 120 then determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130. If the difference between the position of the target in the first image and the position of the target in the second image is not within the predetermined range (step S103: NO), processing resumes from step S101.

[0044] On the other hand, if the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range (step S103: YES), the control unit 130 uses the first and second images to determine the position of the object's eyes (step S201). The method for determining the position of the object's eyes is not particularly limited, but for example, the region in which the object's face exists (face region) may be detected, and the position of the eyes may be estimated from the detected face region.

[0045] Next, the control unit 130 controls the system to capture an iris image of the target based on the identified eye position (step S202). For example, the control unit 130 may control the system to move the camera 18 to a position where it can capture the identified eye position and start capturing. Alternatively, the control unit 130 may control the system to select a camera 18 capable of capturing the identified eye position from among a plurality of cameras 18 at different heights and start capturing. Alternatively, the control unit 130 may control the system to change the imaging range so that it can capture the identified eye position by rotating the mirror on the camera 18 and then start capturing. For example, by placing a mirror within the imaging range of the camera 18 (i.e., so that the camera 18 captures the target via the mirror) and rotating the mirror according to the target's eye position, the imaging range of the camera 18 can be changed and capturing can be started. For example, by rotating the mirror according to the target's eye position, an iris image can be acquired. Note that the movement of the camera 18, the selection of the camera 18, and the driving of the mirror described above may be performed based on a position other than the eye position (i.e., a position of a part other than the eye). For example, the camera 18 may be moved, selected, or the mirror rotated based on the position of the nose or face of the target. For instance, a face image can be acquired based on the face position or the position of the nose located near the center of the face.

[0046] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the second embodiment will be described.

[0047] As explained in Figure 4, in the information processing system 10 according to the second embodiment, an iris image is captured based on the specified eye position. This allows for more appropriate capture of the target iris image. Specifically, it becomes possible to capture the image while keeping the target iris within the imaging range.

[0048] <Third Embodiment> The information processing system 10 according to the third embodiment will be described with reference to Figure 7. Note that the third embodiment differs from the first and second embodiments described above only in some operations; other parts may be identical to those of the first and second embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, while omitting explanations of other overlapping parts as appropriate.

[0049] (Detection of target location) First, with reference to Figure 7, the method for detecting the target position (i.e., the position of the target in each of the first and second images) in the information processing system 10 according to the third embodiment will be described. Figure 7 is a plan view showing an example of the first and second images acquired by the information processing system according to the third embodiment.

[0050] As shown in Figure 7, in the information processing system 10 according to the third embodiment, the positions of the target's right and left eyes are detected as the position of the target in the first and second images. For example, the position of the target may be detected as coordinates indicating the position of the target's right eye and coordinates indicating the position of the target's left eye. The position of the right eye may be the center point in the right eye region, the position of the area indicating the right eye region, the center point in the iris region of the right eye, the position of the area indicating the iris region of the right eye, or the center point in the pupil region of the right eye. Similarly, the position of the left eye may be the center point in the left eye region, the position of the area indicating the left eye region, the center point in the iris region of the left eye, the position of the area indicating the iris region of the left eye, or the center point in the pupil region of the left eye. In this case, trigger determination may be performed using both the position of the target's right eye and the position of the left eye. For example, the difference between the position of the target's right eye in the first image and the position of the target's right eye in the second image, and the difference between the position of the target's left eye in the first image and the position of the target's left eye in the second image, may be calculated, and control may be performed to capture an iris image if both the difference between the right eye and the left eye falls within a predetermined range. Alternatively, control may be performed to capture an iris image if either the difference between the right eye and the left eye falls within a predetermined range.

[0051] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the third embodiment will be described.

[0052] As explained in Figure 7, in the information processing system 10 according to the third embodiment, the positions of the right and left eyes are detected as the position of the target. In this way, trigger determination is performed based on the position of the target's eyes (in other words, the position of the iris), so it is possible to transmit the appropriate timing for capturing an iris image (the target to be transmitted may be a human or a machine). Furthermore, by using the detected position of the target, imaging control based on the position of the eyes can also be performed, as in the second embodiment described above.

[0053] <Fourth Embodiment> The information processing system 10 according to the fourth embodiment will be described with reference to Figures 8 and 9. Note that the fourth embodiment differs from the first to third embodiments described above only in some configurations and operations; other parts may be identical to the first to third embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, while omitting explanations of other overlapping parts as appropriate.

[0054] (Setting the trigger position) First, the trigger position in the information processing system 10 according to the fourth embodiment will be described with reference to Figure 8. Figure 8 is a top view showing the trigger position and focus position in the information processing system according to the fourth embodiment.

[0055] As shown in Figure 8, the information processing system according to the fourth embodiment assumes a situation in which an object approaches a camera that images the object's iris. In particular, in the fourth embodiment, the trigger position (in this example, the point where the optical axis of the first camera 181 that captures the first image intersects with the optical axis of the second camera 182 that captures the second image) is set behind the focal position (i.e., the focus position) as viewed from the camera that captures the object's iris. In the fourth embodiment, when it is determined that the object has reached the trigger position, multiple iris images are captured in succession. Iris image capture is performed continuously at least until the object has passed the trigger point and reached the focal position. Therefore, the multiple iris images captured will include an iris image captured at the focal position. Iris image capture may also be performed after the object has reached the focal position. For example, iris image capture may be terminated after a predetermined number of images have been captured after the object has reached the focal position. When continuously capturing iris images, the imaging range may be adjusted to match the position of the object's eye. For example, the iris image of the subject may be captured by estimating the subject's height and adjusting it to the height of the eye position estimated from that height. In this embodiment, as already described, the position (depth information) of the subject can be determined using the first and second images, so the subject's height can be estimated with high accuracy. Specifically, the subject's height may be estimated (calculated) using the depth information, the size of the subject in the image, and the camera's imaging angle. In this case, the subject's height can be appropriately estimated even if there is no reference object in the image that serves as a length reference.

[0056] (Flow of operations) Next, the operation flow of the information processing system 10 according to the fourth embodiment will be described with reference to Figure 9. Figure 9 is a flowchart showing the operation flow of the information processing system according to the fourth embodiment. Note that in Figure 9, the same reference numerals are used for the same processes as shown in Figure 5.

[0057] As shown in Figure 9, when the information processing system 10 according to the fourth embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0058] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The determination unit 120 then determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130. If the difference between the position of the target in the first image and the position of the target in the second image is not within the predetermined range (step S103: NO), processing resumes from step S101.

[0059] On the other hand, if the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range (step S103: YES), the control unit 130 continuously captures iris images (step S401). After that, the control unit 130 determines whether or not to terminate continuous imaging (step S402). The control unit 130 may determine to terminate continuous imaging, for example, when the object passes the focal position (see Figure 8). Alternatively, the control unit 130 may determine to terminate imaging when the difference between the position of the object in the first image and the position of the object in the second image is no longer within a predetermined range.

[0060] If it is not determined that imaging should be terminated (step S402: NO), continuous acquisition of iris images continues. On the other hand, if it is determined that imaging should be terminated (step S402: YES), continuous acquisition of iris images is terminated and the series of operations ends.

[0061] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the fourth embodiment will be described.

[0062] As explained in Figures 8 and 9, in the information processing system 10 according to the fourth embodiment, the trigger position (i.e., the position where the optical axes intersect) is set behind the focal position of the camera that images the iris, and when the target reaches the trigger position, iris images are continuously captured. In this way, the iris of an object approaching the camera can be appropriately captured at the focal position.

[0063] <Fifth Embodiment> The information processing system 10 according to the fifth embodiment will be described with reference to Figures 10 and 11. Note that the fifth embodiment differs from the fourth embodiment described above only in some configurations and operations; other parts may be the same as those of the first to fourth embodiments. Therefore, the following will describe in detail the parts that differ from each embodiment already described, while other overlapping parts will be omitted as appropriate.

[0064] (Functional configuration) First, the functional configuration of the information processing system 10 according to the fifth embodiment will be described with reference to Figure 10. Figure 10 is a block diagram showing the functional configuration of the information processing system according to the fifth embodiment. Note that in Figure 10, the same reference numerals are used for components as those shown in Figure 2.

[0065] As shown in Figure 10, the information processing system 10 according to the fifth embodiment is configured to include an acquisition unit 110, a determination unit 120, a control unit 130, a selection unit 140, and an authentication unit 150 as components for realizing its functions. That is, the information processing system 10 according to the fifth embodiment further includes a selection unit 140 and an authentication unit 150 in addition to the configuration of the first embodiment (see Figure 2). Note that the selection unit 140 and the authentication unit 150 may each be a processing block realized by, for example, the processor 11 (see Figure 1) described above.

[0066] The selection unit 140 is configured to select at least one high-quality iris image from among multiple iris images captured consecutively after trigger detection. The quality of the iris image may be determined, for example, by calculating a quality score (i.e., a score indicating the quality of the image). For example, the selection unit 140 may select the image with the highest quality score from among multiple iris images. Alternatively, the selection unit 140 may select a predetermined number of images in descending order of quality score. Alternatively, the selection unit 140 may select an image whose quality score exceeds a predetermined value.

[0067] The authentication unit 150 is configured to perform biometric authentication processing (i.e., iris authentication) based on the iris image of the target captured as a result of control by the control unit 130. Note that a detailed explanation of the specific iris authentication method is omitted here, as existing technologies can be appropriately adopted. The authentication unit 150 may be configured to perform various processes depending on the result of iris authentication. For example, the authentication unit 150 may be configured to perform a process to unlock the gate if iris authentication is successful.

[0068] (Flow of operations) Next, the operation flow of the information processing system 10 according to the fifth embodiment will be described with reference to Figure 11. Figure 11 is a flowchart showing the operation flow of the information processing system according to the fifth embodiment. Note that in Figure 11, the same reference numerals are used for the same processes as shown in Figure 9.

[0069] As shown in Figure 11, when the information processing system 10 according to the fifth embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0070] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The determination unit 120 then determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130. If the difference between the position of the target in the first image and the position of the target in the second image is not within the predetermined range (step S103: NO), processing resumes from step S101.

[0071] On the other hand, if the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range (step S103: YES), the control unit 130 continuously captures iris images (step S401). After that, the control unit 130 determines whether or not to terminate the continuous imaging (step S402). If it is not determined that imaging should be terminated (step S402: NO), the continuous imaging of iris images continues.

[0072] On the other hand, if it is determined that imaging should be terminated (step S402: YES), continuous acquisition of iris images is terminated, and the selection unit 140 selects at least one high-quality image from the multiple iris images acquired up to that point (step S501). Then, the authentication unit performs iris authentication using the iris image selected by the selection unit 140 (step S502).

[0073] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the fifth embodiment will be described.

[0074] As explained in Figures 10 and 11, in the information processing system 10 according to the fifth embodiment, a high-quality image is selected from among multiple iris images, and authentication processing is performed using the selected image. In this way, since authentication processing can be performed using a high-quality iris image, highly accurate biometric authentication can be achieved.

[0075] <Sixth Embodiment> The information processing system 10 according to the sixth embodiment will be described with reference to Figure 12. Note that the sixth embodiment differs from the first to fifth embodiments described above only in some configurations; other parts may be identical to those of the first to fifth embodiments. Therefore, the following will describe in detail the parts that differ from each embodiment already described, while omitting explanations of other overlapping parts as appropriate.

[0076] (Camera configuration) First, the camera configuration of the information processing system 10 according to the sixth embodiment will be described with reference to Figure 12. Figure 12 is a block diagram showing the functional configuration of the information processing system according to the sixth embodiment. Note that in Figure 12, the same reference numerals are used for elements similar to those shown in Figure 2.

[0077] As shown in Figure 12, the information processing system 10 according to the sixth embodiment includes a camera 18 consisting of a first camera 183, a second camera 182, and a third camera 183. The first camera 181 is provided as a camera for capturing a first image. The second camera 182 is provided as a camera for capturing a second image. The first and second images captured by the first camera 181 and the second camera 182 are acquired by the acquisition unit 110. The first camera 181 and the second camera 182 are arranged so that their optical axes intersect, as shown in Figure 3. The third camera 183 is provided as a near-infrared camera for capturing an iris image. For this reason, the third camera 183 is controllable by the control unit 130. Specific arrangement examples of the first camera 181, the second camera 182, and the third camera will be described in detail in other embodiments described later.

[0078] The first camera 181 and the second camera 182 described above may be pre-calibrated. In this case, it becomes possible to acquire the position (depth information) of an object with high accuracy using stereo vision. Since the first camera 181 and the second camera 182 are arranged so that their optical axes intersect, by limiting the stereo search range to the center of the field of view and using corresponding point information of an object determined to be located near the trigger (for example, information regarding eye coordinates or facial feature coordinates), high-precision depth information can be acquired.

[0079] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the sixth embodiment will be described.

[0080] As explained in Figure 12, in the information processing system 10 according to the sixth embodiment, the first image is captured by the first camera 181, the second image by the second camera 182, and the iris image by the third camera 183. In this way, the first, second, and third images can be appropriately captured using multiple cameras. Furthermore, the position of the object can be determined with higher accuracy compared to the case where the first and second images are captured by a single camera common to both.

[0081] <Seventh Embodiment> The information processing system 10 according to the seventh embodiment will be described with reference to Figure 13. Note that the seventh embodiment describes a specific example of camera arrangement in the sixth embodiment described above, and other parts may be the same as those of the first to sixth embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, and will omit explanations of other overlapping parts as appropriate.

[0082] (Camera placement) First, the camera arrangement of the information processing system 10 according to the seventh embodiment will be described with reference to Figure 13. Figure 13 is a top view showing an example of the arrangement of the first camera, second camera, and third camera in the information processing system according to the seventh embodiment. Note that in Figure 13, the same reference numerals are used for components as shown in Figure 12.

[0083] As shown in Figure 13, in the information processing system 10 according to the seventh embodiment, the third camera 183 is positioned in front of an object approaching the camera. Here, "front" refers to a position from which the object's face can be imaged from the front (i.e., a position directly facing the object). The first camera 181 and the second camera 182 are positioned to the left and right of the third camera, respectively. Here, the first camera 181 is positioned to the right of the third camera 183 and the second camera 182 is positioned to the left of the third camera 183, but the second camera 182 may be positioned to the right of the third camera 183 and the first camera 181 may be positioned to the left of the third camera 183.

[0084] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the seventh embodiment will be described.

[0085] As explained in Figure 13, in the information processing system 10 according to the seventh embodiment, the third camera 183 is positioned in front of the object, and the first camera 181 and the second camera 182 are positioned to the left and right of the third camera 183, respectively. In this way, the iris image can be captured from the front of the object at an appropriate angle. Furthermore, the first and second images can also be captured appropriately so that their optical axes intersect.

[0086] <Eighth Embodiment> The information processing system 10 according to the eighth embodiment will be described with reference to Figure 14. The eighth embodiment, like the seventh embodiment described above, describes a specific example of camera arrangement in the sixth embodiment, and other parts may be the same as those of the first to sixth embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, and will omit explanations of other overlapping parts as appropriate.

[0087] (Camera placement) First, the camera arrangement of the information processing system 10 according to the eighth embodiment will be described with reference to Figure 14. Figure 14 is a top view showing an example of the arrangement of the first camera, second camera, and third camera in the information processing system according to the eighth embodiment. Note that in Figure 14, the same reference numerals are used for components as shown in Figure 13.

[0088] As shown in Figure 14, in the information processing system 10 according to the eighth embodiment, the first camera 181, the second camera 182, and the third camera 183 are each positioned to capture images of the target from an oblique angle. Here, "oblique" means an angle that is offset from the front of the target.

[0089] Figure 14 shows an example where the first camera 181 and the second camera 182 are positioned to the right of the object, and the third camera 183 is positioned to the left of the object. However, the camera configuration of this embodiment is not limited to this arrangement. For example, the first camera 181, the second camera 182, and the third camera 183 may all be positioned to the right of the object. Alternatively, the first camera 181 may be positioned to the right of the object, and the second camera 182 may be positioned to the left of the object.

[0090] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the eighth embodiment will be described.

[0091] As explained in Figure 14, in the information processing system 10 according to the eighth embodiment, the first camera 181, the second camera 182, and the third camera 183 are each positioned to image the object from an oblique angle, offset from the front. In this way, the first image, the second image, and the iris image of the object can be captured without hindering the movement of the object approaching the camera.

[0092] <Ninth Embodiment> The information processing system 10 according to the ninth embodiment will be described with reference to Figures 15 and 16. The ninth embodiment differs from the first to eighth embodiments described above only in some configurations and operations; other parts may be identical to the first to eighth embodiments. Therefore, the following will provide a detailed explanation of the parts that differ from the embodiments already described, while other overlapping parts will be omitted as appropriate.

[0093] (Camera configuration) First, the camera configuration of the information processing system 10 according to the ninth embodiment will be described with reference to Figure 15. Figure 15 is a front view showing an example of the arrangement of the fourth camera and mirror in the information processing system according to the ninth embodiment.

[0094] As shown in Figure 15, in the information processing system 10 according to the ninth embodiment, a fourth camera 184 is provided as a camera for capturing the first image and the second image. The fourth camera 184 is positioned to face directly upwards, and a mirror 200 is positioned above the camera. Therefore, the fourth camera 184 includes the mirror 200 in its imaging range. The fourth camera 184 captures the object (i.e., the first image and the second image) through this mirror 200.

[0095] The mirror 200 has a first surface 201 and a second surface 202 at different angles. The first surface is provided for capturing a first image, and the second surface 202 is provided for capturing a second image. Therefore, the first surface 201 and the second surface 202 are at an angle such that the optical axis of the fourth camera 184 intersects at the trigger point. In addition, the entire mirror 200 is positioned at an angle of, for example, 45 degrees with respect to the horizontal direction. By angling the mirror 200 in this way, the fourth camera 184 is able to capture the front (i.e., the front side of the paper) through the mirror 200.

[0096] Furthermore, the first surface 201 and the second surface 202 of the mirror 200 do not necessarily have to be clearly separated regions as shown in Figure 15. For example, a part of the bent mirror 200 may be used as the first surface 201 and the other part as the second surface 202. Also, the first surface 201 and the second surface 202 of the mirror may be configured to be present in separate mirrors. For example, a first mirror having the first surface 201 and a second mirror having the second surface 202 may be provided separately at different angles to each other.

[0097] (First image and second image) Next, with reference to Figure 16, the first and second images acquired by the information processing system 10 according to the ninth embodiment will be described in detail. Figure 16 is a plan view showing an example of the first and second images acquired by the information processing system according to the ninth embodiment.

[0098] As shown in Figure 16, in the information processing system 10 according to the ninth embodiment, the first image and the second image are acquired as a single image. Specifically, the acquired image includes a first image captured via the first surface 201 of the mirror 200 and a second image captured via the second surface 202. Even when the first image and the second image are acquired as a single image in this way, it is possible to determine that the target has reached the trigger point by arranging them so that the optical axes for capturing each image intersect at the trigger point.

[0099] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the ninth embodiment will be described.

[0100] As explained in Figures 15 and 16, in the information processing system 10 according to the ninth embodiment, the first image and the second image are captured through the first surface 201 and the second surface 202 of the mirror 200. In this way, both the first image and the second image can be captured with a single camera (i.e., the fourth camera 184). Therefore, compared to a configuration in which the first and second images are captured with multiple cameras, it is possible to reduce costs.

[0101] In the example described above, the mirror 200 was shown to have two surfaces, but the mirror may have three or more surfaces. For example, the mirror 200 may have a third surface in addition to the first surface 201 and the second surface 202. Such a configuration may be realized, for example, by bending one mirror in two places, or by using three mirrors. Each of the three surfaces may be provided as, for example, a surface for imaging the target from the right side, a surface for imaging from the front, and a surface for imaging from the left side. In this case, in addition to the first and second images, a third image captured via the third surface may be used to determine whether the target has reached the trigger point. When using the first, second, and third images, the determination unit 120 may determine whether the difference between the target position in the first image, the target position in the second image, and the target position in the third image is within a predetermined range. If these differences are within the predetermined range, the iris image of the target may be captured. Furthermore, face recognition may be performed using the surface used for imaging from the front among the three surfaces. Alternatively, facial recognition may be performed using facial images reflected from a plane used to image the subject from the right side, a plane used to image the subject from the front, and a plane used to image the subject from the left side. In this case, the weight (i.e., the degree of influence on facial recognition) of the facial image obtained from the plane used to image the subject from the front may be made greater than that of the facial images obtained from the other planes (i.e., planes used to image the subject from the right and left sides). This is because there is a higher probability of obtaining a more reliable facial image (for example, a front-facing facial image) when the subject is imaged from the front than when the subject is imaged from the right or left side.

[0102] <Tenth Embodiment> The information processing system 10 according to the 10th embodiment will be described with reference to Figures 17 and 18. Note that the 10th embodiment differs from the first to 9th embodiments described above only in some configurations and operations; other parts may be identical to the first to 9th embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, while omitting explanations of other overlapping parts as appropriate.

[0103] (Camera configuration) First, the camera configuration of the information processing system 10 according to the 10th embodiment will be described with reference to Figure 17. Figure 17 is a top view showing an example of the arrangement of the 5th camera and mirror in the information processing system according to the 10th embodiment.

[0104] As shown in Figure 17, the information processing system 10 according to the 10th embodiment is provided with a fifth camera 185 as a camera for capturing the first and second images. A mirror 250 is also provided within the imaging range of the fifth camera 185. The fifth camera 185 and the mirror 250 are arranged so that the optical axis extending directly from the fifth camera 185 toward the trigger position intersects with the optical axis extending from the fifth camera 185 toward the trigger position via the mirror 250.

[0105] (First image and second image) Next, with reference to Figure 18, the first and second images acquired by the information processing system 10 according to the 10th embodiment will be described in detail. Figure 18 is a plan view showing an example of the first and second images acquired by the information processing system according to the 10th embodiment.

[0106] As shown in Figure 18, in the information processing system 10 according to the 10th embodiment, the first image and the second image are acquired as a single image. Specifically, the first image, which is acquired by directly imaging the object, includes the second image, which is captured via the mirror 250. Even when the first and second images are acquired as a single image in this way, it is possible to determine that the object has reached the trigger point by arranging the optical axes used when imaging each image to intersect at the trigger point. For example, in the example shown in Figure 18, the object is captured near the center of the first image (i.e., near the center of the entire acquired image), and the object is captured near the center of the second image (i.e., near the center of the mirror 250 portion). Therefore, in such a case, it can be determined that the object is present at the trigger point.

[0107] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the tenth embodiment will be described.

[0108] As explained in Figures 17 and 18, in the information processing system 10 according to the 10th embodiment, the target is imaged directly by the fifth camera 185 and also imaged via the mirror 250. In this way, the first and second images can be captured with a single camera (i.e., the fifth camera 185). Therefore, compared to a configuration in which the first and second images are captured with multiple cameras, costs can be reduced. It is also possible to acquire more images with a single camera by increasing the number of mirrors or by bending the mirrors to increase the number of surfaces. For example, if the first and second mirrors are installed within the imaging range of the fifth camera 185, the second image can be acquired via the first mirror and the third image via the second mirror. In this case, by using the third image in addition to the first and second images, the timing of the image capture can be controlled with greater precision.

[0109] <Embodiment 11> The information processing system 10 according to the 11th embodiment will be described with reference to Figures 19 and 20. Note that the 11th embodiment differs from the first to tenth embodiments described above only in some configurations and operations; other parts may be identical to the first to tenth embodiments. Therefore, the following will describe in detail the parts that differ from each embodiment already described, while omitting explanations of other overlapping parts as appropriate.

[0110] (Functional configuration) First, the functional configuration of the information processing system 10 according to the 11th embodiment will be described with reference to Figure 19. Figure 19 is a block diagram showing the functional configuration of the information processing system according to the 11th embodiment. Note that in Figure 19, the same reference numerals are used for components as those shown in Figure 2.

[0111] As shown in Figure 19, the information processing system 10 according to the 11th embodiment is configured to include an acquisition unit 110, a determination unit 120, a control unit 130, and a specification unit 160 as components for realizing its functions. That is, the information processing system 10 according to the 11th embodiment further includes a specification unit 160 in addition to the configuration of the first embodiment (see Figure 2). The specification unit 160 may be, for example, a processing block realized by the processor 11 (see Figure 1) described above.

[0112] The identification unit 160 is configured to identify the target for trigger determination (in other words, the target for which the iris image is captured). Based on the identification result by the identification unit 160, the determination unit 120 performs trigger determination using the difference in position between the first image and the second image of the target identified by the identification unit 160. The identification method of the identification unit 160 is not particularly limited and only needs to be able to guarantee that the target in the first image and the target in the second image are the same person. The identification unit 160 may identify the target using, for example, facial recognition. In this case, facial recognition may be performed using the first image and the second image, or using a separately captured image.

[0113] (Flow of operations) Next, the operation flow of the information processing system 10 according to the 11th embodiment will be described with reference to Figure 20. Figure 20 is a flowchart showing the operation flow of the information processing system according to the 11th embodiment. Note that in Figure 20, the same reference numerals are used for the same processes as shown in Figure 5.

[0114] As shown in Figure 20, when the information processing system 10 according to the 11th embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120 and the identification unit 160.

[0115] Next, the identification unit 160 identifies the target for trigger determination (step S1101). Then, the determination unit 120 detects the position of the target identified by the identification unit 160 from the first image and the second image acquired by the acquisition unit 110 (step S1102). Note that the processes of step S1101 and step S1102 may be executed sequentially. That is, step S1101 may be executed after step S1102. In this case, the identification unit 160 should identify the target if the determination unit 120 determines that the position of the target is within a predetermined range.

[0116] Next, the determination unit 120 determines whether the difference between the position of the identified object in the first image and the position of the identified object in the second image is within a predetermined range (step S1103). The determination result from the determination unit 120 is output to the control unit 130. If the difference between the position of the identified object in the first image and the position of the identified object in the second image is not within the predetermined range (step S1103: NO), processing is resumed from step S101.

[0117] On the other hand, if the difference between the position of the identified object in the first image and the position of the identified object in the second image is within a predetermined range (step S1103: YES), the control unit 130 controls the system to capture an iris image of the object (step S104).

[0118] In the information processing system 10 according to the 11th embodiment, a trigger determination is made for an object only if the object captured in the first image and the object captured in the second image are the same person (i.e., a specified object). Therefore, for example, if the first object is captured in the first image and the second object is captured in the second image, the difference between the position of the first object in the first image and the position of the second object in the second image will not be used for the trigger determination.

[0119] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the 11th embodiment will be described.

[0120] As explained in Figures 19 and 20, in the information processing system 10 according to the 11th embodiment, a trigger determination is performed using the first and second images after the target has been identified. This prevents incorrect trigger determinations from being made based on the positions of different targets.

[0121] <Twelfth Embodiment> The information processing system 10 according to the 12th embodiment will be described with reference to Figure 21. Note that the 12th embodiment differs from the first to 11th embodiments described above only in some operations; other parts may be identical to the first to 11th embodiments. Therefore, the following will describe in detail the parts that differ from each embodiment already described, while omitting explanations of other overlapping parts as appropriate.

[0122] (Flow of operations) First, the operation flow of the information processing system 10 according to the 12th embodiment will be explained with reference to Figure 21. Figure 21 is a flowchart showing the operation flow of the information processing system according to the 12th embodiment. Note that in Figure 21, the same reference numerals are used for the same processes as shown in Figure 5.

[0123] As shown in Figure 21, when the information processing system 10 according to the 12th embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0124] Next, the determination unit 120 determines whether multiple subjects are captured in the first and second images (step S1201). If multiple subjects are captured in the first and second images (step S1201: YES), the determination unit 120 selects one subject from the multiple subjects (step S1202). The determination unit 120 may, for example, select the subject closest to the camera (for example, the subject that is most prominently featured). The following processing is performed on the subject selected in step S1202. If multiple subjects are not captured in the first and second images (step S1201: NO), the processing in step S1202 may be omitted.

[0125] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The determination unit 120 then determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130.

[0126] If the difference between the position of the target in the first image and the position of the target in the second image is not within a predetermined range (step S103: NO), processing is resumed from step S101. On the other hand, if the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103: YES), the control unit 130 controls the system to capture an iris image of the target (step S104).

[0127] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the 12th embodiment will be described.

[0128] As explained in Figure 21, in the information processing system 10 according to the 12th embodiment, when multiple objects are captured in the first and second images, a trigger determination is made for one selected object. In this way, even when multiple objects are present, it is possible to capture the iris image of each object at the appropriate timing.

[0129] <13th Embodiment> The information processing system 10 according to the 13th embodiment will be described with reference to Figure 22. Note that the 13th embodiment differs from the first to 12 embodiments described above only in some operations; other parts may be identical to the first to 12 embodiments. Therefore, the following will describe in detail the parts that differ from each embodiment already described, and will omit explanations of other overlapping parts as appropriate.

[0130] (Flow of operations) First, the operation flow of the information processing system 10 according to the 13th embodiment will be explained with reference to Figure 22. Figure 22 is a flowchart showing the operation flow of the information processing system according to the 13th embodiment. Note that in Figure 22, the same reference numerals are used for the same processes as shown in Figure 5.

[0131] As shown in Figure 22, when the information processing system 10 according to the 13th embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0132] Next, the determination unit 120 detects the position of the target from the first image and the second image acquired by the acquisition unit 110 (step S102). The determination unit 120 then determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). If the difference between the position of the target in the first image and the position of the target in the second image is not within the predetermined range (step S103: NO), the process is restarted from step S101.

[0133] On the other hand, if the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range (step S103: YES), the determination unit 120 further determines whether or not there are any companions passing by at the same time as the object (step S1301). Examples of companions include a person walking alongside the object or a baby being held by the object. The determination unit 120 may determine the presence of companions using the first and second images, or it may determine the presence of companions using other images.

[0134] If there are no companions with the subject (step S1301: NO), the control unit 130 controls the system to capture an iris image of the subject (step S104). On the other hand, if there are companions with the subject (step S1301: YES), the control unit 130 captures the iris image of the subject and the iris images of the companions in parallel using different cameras (step S1302). Even if there are multiple companions, the system can capture iris images in parallel for as many times as there are cameras. If there are not enough cameras, the system may capture only the selected companions, as in the 12th embodiment described above (see Figure 21).

[0135] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the 13th embodiment will be described.

[0136] As explained in Figure 22, in the information processing system 10 according to the 13th embodiment, when multiple objects are captured in the first and second images (especially when multiple objects simultaneously add focus points), the iris image of each object is captured by a different camera. In this way, even when multiple objects are present, it is possible to capture the iris image of each object at the appropriate timing.

[0137] <14th Embodiment> The information processing system 10 according to the 14th embodiment will be described with reference to Figures 23 and 24. Note that the 14th embodiment differs from the first to 13 embodiments described above only in some operations; other parts may be identical to the first to 13 embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, while other overlapping parts will be omitted as appropriate.

[0138] (Flow of operations) First, the operation flow of the information processing system 10 according to the 14th embodiment will be explained with reference to Figure 23. Figure 23 is a flowchart showing the operation flow of the information processing system according to the 14th embodiment. Note that in Figure 23, the same reference numerals are used for the same processes as shown in Figure 5.

[0139] As shown in Figure 23, when the information processing system 10 according to the 14th embodiment starts operation, the acquisition unit 110 first acquires the first image and the second image (step S101). The first image and the second image acquired by the acquisition unit 110 are output to the determination unit 120.

[0140] Next, the determination unit 120 detects the position of the object in the first image (step S1401). Then, the determination unit 120 determines the search area in the second image based on the position of the object in the first image (step S1402). The search area is determined on the second image as the area in which the presence of the object is searched. The method for determining the search area will be explained in detail later.

[0141] Next, the determination unit 120 searches for the target in the search area of ​​the second image (step S1403). If the presence of the target is detected in the search area (step S1404), the determination unit 120 detects the position of the target detected in the search area as the position of the target in the second image (step S1405). If the presence of the target cannot be detected in the search area, processing may be restarted from step S101.

[0142] When the position of the target in the first and second images is detected, the determination unit 120 determines whether the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103). The determination result from the determination unit 120 is output to the control unit 130.

[0143] If the difference between the position of the target in the first image and the position of the target in the second image is not within a predetermined range (step S103: NO), processing is resumed from step S101. On the other hand, if the difference between the position of the target in the first image and the position of the target in the second image is within a predetermined range (step S103: YES), the control unit 130 controls the system to capture an iris image of the target (step S104).

[0144] (search area) Next, with reference to Figure 24, the search area set in the second image described above will be explained in detail. Figure 24 is a plan view showing an example of the first and second images acquired by the information processing system according to the 14th embodiment, and their search area.

[0145] As shown in Figure 24, in the information processing system 10 according to the 14th embodiment, the search area is determined as the area corresponding to the area where the object was detected in the first image. For example, in the example shown in Figure 24(a), the object is detected near the left edge of the first image. In this case, the area near the left edge of the second image is determined as the search area, but since the object is not included in that area, the object will not be detected in the second image. On the other hand, in the example shown in Figure 24(b), the object is detected near the center of the first image, so the area near the center of the second image is determined as the search area. Since the object is included in that search area, the object will be detected in the second image.

[0146] (Technical effects) Next, the technical effects obtained by the information processing system 10 according to the 14th embodiment will be described.

[0147] As explained in Figures 23 and 24, in the information processing system 10 according to the 14th embodiment, the region in the first image where the object exists is set as the search region for the object in the second image. In this way, when detecting the position of the object in the second image, it is not necessary to search the entire image. As a result, the process of detecting the position of the object in the second image can be performed quickly and with low load.

[0148] The processing method of recording a program that operates the configuration of each embodiment in order to realize the functions of each embodiment described above on a recording medium, reading the program recorded on the recording medium as code, and executing it on a computer is also included in the scope of each embodiment. In other words, a computer-readable recording medium is also included in the scope of each embodiment. Furthermore, not only the recording medium on which the above-mentioned program is recorded, but also the program itself is included in each embodiment.

[0149] Examples of recording media that can be used include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, magnetic tapes, non-volatile memory cards, and ROMs. Furthermore, the scope of each embodiment is not limited to programs that perform processing on the recording media alone, but also includes programs that operate on the OS and perform processing in cooperation with other software and the functions of expansion boards. In addition, the program itself may be stored on a server, and part or all of the program may be made available for download from the server to the user terminal.

[0150] <Note> The embodiments described above may also be described in the following appendix, but are not limited to these.

[0151] (Note 1) The information processing system described in Appendix 1 is an information processing system comprising: acquisition means for acquiring a first image and a second image captured so that the optical axes intersect at a predetermined point; determination means for determining whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range; and control means for controlling the system to capture an iris image of the object if the difference is within the predetermined range.

[0152] (Note 2) The information processing system described in Appendix 2 is the information processing system described in Appendix 1, wherein the control means identifies the eye position of the target from the first image and the second image, and controls the system to capture the iris image based on the identified eye position.

[0153] (Note 3) The information processing system described in Appendix 3 is the information processing system described in Appendix 1 or 2, wherein the position of the object in the first image and the second image is the position of the object's right eye and left eye.

[0154] (Note 4) The information processing system described in Appendix 4 is the information processing system described in any one of Appendix 1 to 3, wherein the predetermined position is set to be behind the focal position as viewed from the camera that captures the iris image, and the control means controls the camera to capture the iris image of the target to be continuously captured after the difference falls within the predetermined range.

[0155] (Note 5) The information processing system described in Appendix 5 is the information processing system described in Appendix 4, further comprising: selection means for selecting at least one iris image of high quality from a plurality of iris images captured in succession; and authentication means for performing iris authentication using the selected iris image.

[0156] (Note 6) The information processing system described in Appendix 6 is the information processing system described in any one of Appendix 1 to 5, wherein the acquisition means acquires the first image captured by the first camera and the second image captured by the second camera which is installed at a different angle from the first camera, and the control means controls the third camera, which is different from the first and second cameras, to capture the iris image.

[0157] (Note 7) The information processing system described in Appendix 7 is the information processing system described in Appendix 6, wherein the third camera is positioned in front of the object, and the first and second cameras are positioned to the left and right of the third camera, respectively.

[0158] (Note 8) The information processing system described in Appendix 8 is the information processing system described in Appendix 6, wherein each of the first camera, the second camera, and the third camera is positioned to image the target at an oblique angle offset from the front.

[0159] (Note 9) The information processing system described in Appendix 9 is the information processing system described in any one of Appendix 1 to 5, wherein the acquisition means acquires the first image captured by the fourth camera through the first surface of the mirror and the second image captured by the fourth camera through the second surface of the mirror.

[0160] (Note 10) The information processing system described in Appendix 10 is the information processing system described in any one of Appendix 1 to 5, wherein the acquisition means acquires the first image directly captured by the fifth camera and the second image captured by the fifth camera via a mirror.

[0161] (Note 11) The information processing system described in Appendix 11 further comprises a means for identifying the target, and the determination means determines whether the difference between the position of the identified target in the first image and the position of the identified target in the second image is within the predetermined range, as described in any one of Appendix 1 to 10.

[0162] (Note 12) The information processing system described in Appendix 12 is the information processing system described in any one of Appendix 1 to 11, wherein the control means controls the system to select one person from the multiple subjects when multiple subjects are captured in the first image and the second image, and to capture the iris image of the selected subject.

[0163] (Note 13) The information processing system described in Appendix 13 is the information processing system described in any one of Appendix 1 to 11, wherein the control means controls the capture of the iris images of the multiple objects with a different camera for each object when multiple objects are captured in the first image and the second image.

[0164] (Note 14) The information processing system described in Appendix 14 is the information processing system described in any one of Appendix 1 to 13, wherein the determination means detects a first region in which the object is captured in the first image, and then searches whether or not the object is present in a second region corresponding to the first region in the second image.

[0165] (Note 15) The information processing method described in Appendix 15 is an information processing method which involves acquiring a first image and a second image captured so that the optical axes intersect at a predetermined point using at least one computer, determining whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range, and controlling the system to capture an iris image of the object if the difference is within the predetermined range.

[0166] (Note 16) The recording medium described in Appendix 16 is a recording medium on which a computer program is recorded that causes at least one computer to execute an information processing method that acquires a first image and a second image taken so that the optical axes intersect at a predetermined point, determines whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range, and controls the computer to take an iris image of the object if the difference is within the predetermined range.

[0167] (Note 17) The information processing device described in Appendix 17 is an information processing device comprising: acquisition means for acquiring a first image and a second image captured so that the optical axes intersect at a predetermined point; determination means for determining whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range; and control means for controlling the device to capture an iris image of the object if the difference is within the predetermined range.

[0168] (Note 18) The computer program described in Appendix 18 is a computer program that causes at least one computer to execute an information processing method that acquires a first image and a second image taken so that the optical axes intersect at a predetermined point, determines whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range, and controls the computer to take an iris image of the object if the difference is within the predetermined range.

[0169] This disclosure may be modified as appropriate, insofar as it does not contradict the gist or idea of ​​the invention as can be inferred from the claims and the specification as a whole, and information processing systems, information processing methods, and recording media that include such modifications are also included in the technical idea of ​​this disclosure. [Explanation of Symbols]

[0170] 10. Information Processing Systems 11 processors 18 Cameras 110 Acquisition Department 120 Judgment section 130 Control Unit 140 Selection Section 150 Certification Department 160 Specific section 181 Camera 1 182 Second Camera 183 Third Camera 184 Fourth Camera 185 Fifth Camera 200 Mirror 201 First side 202 Second side 250 Mirror

Claims

1. Acquisition means for acquiring a first image and a second image captured so that the optical axes intersect at a predetermined point, A determination means that, after detecting a first region in which the object is captured in the first image, searches whether the object is present in a second region corresponding to the first region in the second image, and determines whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range. A control means that controls the imaging of the target iris image when the difference is within the predetermined range, An information processing system equipped with the following features.

2. The control means identifies the eye position of the target from the first image and the second image, and controls the system to capture the iris image based on the identified eye position. The information processing system according to claim 1.

3. The positions of the object in the first and second images are the positions of the object's right and left eyes. The information processing system according to claim 1 or 2.

4. The aforementioned predetermined point is set to be behind the focal point as viewed from the camera that captures the iris image. The control means controls the camera to capture the iris image of the target as it approaches the camera after the difference falls within the predetermined range. The information processing system according to any one of claims 1 to 3.

5. A selection means for selecting at least one iris image of high quality from among a plurality of iris images captured in succession, Authentication means that performs iris authentication using the selected iris image, The information processing system according to claim 4, further comprising:

6. The acquisition means acquires the first image captured by the first camera and the second image captured by the second camera, which is installed at a different angle from the first camera. The control means controls the third camera, which is different from the first and second cameras, to capture the iris image. The information processing system according to any one of claims 1 to 5.

7. The third camera is positioned in front of the object, The first camera and the second camera are positioned to the left and right of the third camera, respectively. The information processing system according to claim 6.

8. Each of the first camera, the second camera, and the third camera is positioned to capture images of the object at an oblique angle, offset from the front. The information processing system according to claim 6.

9. By at least one computer, First and second images are acquired so that the optical axes intersect at a predetermined point. After detecting the first region in which the object is captured in the first image, the system searches whether the object exists in the second region corresponding to the first region in the second image, and determines whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range. If the difference is within the predetermined range, control the system to capture an image of the target iris. Information processing methods.

10. On at least one computer, First and second images are acquired so that the optical axes intersect at a predetermined point. After detecting the first region in which the object is captured in the first image, the system searches whether the object exists in the second region corresponding to the first region in the second image, and determines whether the difference between the position of the object in the first image and the position of the object in the second image is within a predetermined range. If the difference is within the predetermined range, control the system to capture an image of the target iris. A computer program that executes information processing methods.

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