JP2022126383A - Imaging control device, imaging control method, and program - Google Patents

Abstract

To optimize each exposure correction of an area in which an authentication object is detected and an area in which an authentication object is not detected yet.SOLUTION: An imaging control device according to one embodiment comprises: detection means which detects an authentication object from an image; setting means which sets a first area including the authentication object detected by the detection means, to the image; and adjustment means which adjusts each exposure time of the first area set by the setting means and a second area in which the authentication object is not detected yet.SELECTED DRAWING: Figure 1

Description

The present invention relates to an imaging control device, an imaging control method, and a program.

Japanese Patent Application Laid-Open No. 2002-200000 discloses that brightness correction is performed based on brightness information used to determine the exposure condition for an image obtained by imaging using the exposure condition determined based on the brightness information of the face area of the subject. Techniques are disclosed.

JP 2014-187722 A

The problem to be solved by the present invention is to optimize the exposure correction for each of an area where an authentication target is detected and an area where an authentication target is not detected.

An imaging control apparatus according to one aspect of the present invention includes detection means for detecting an authentication target from an image; setting means for setting a first area including the authentication target detected by the detection means in the image; adjusting means for adjusting the exposure time of each of the first area set by means and the second area in which the authentication target is not detected.

It is possible to optimize the exposure correction for each of the area where the authentication target is detected and the area where the authentication target is not detected.

1 is a block diagram showing a configuration example of an imaging device according to a first embodiment; FIG. FIG. 5 is a diagram showing an example of a captured image at the time of authentication according to the first embodiment; FIG. 5 is a diagram showing an example of luminance values of a captured image during authentication according to the first embodiment; FIG. 4 is a diagram showing an example of a captured image and luminance values after authentication area setting according to the first embodiment; FIG. 7 is a diagram showing an example of a captured image when the authentication area is moved according to the first embodiment; FIG. 5 is a diagram showing an example of a captured image when there are multiple authentication areas according to the first embodiment; 4 is a flowchart showing an imaging control method according to the first embodiment; FIG. 11 is a diagram showing an example of a captured image and luminance values after authentication area setting according to the second embodiment; FIG. 11 is a diagram showing an example of a captured image when an authentication area is moved according to the second embodiment; FIG. 11 is a diagram showing an example of a captured image when there are multiple authentication areas according to the second embodiment; FIG. 11 is a diagram showing an example of captured images before and after authentication according to the third embodiment; FIG. 2 is a block diagram showing a hardware configuration example of an imaging control unit according to the embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the present invention, and not all combinations of features described in the embodiments are essential for solving means of the present invention. The configuration of the embodiment can be appropriately modified or changed according to the specifications of the device to which the present invention is applied and various conditions (use conditions, use environment, etc.). The technical scope of the present invention is defined by the claims and is not limited by the following individual embodiments.

<First Embodiment>
FIG. 1 is a block diagram showing a configuration example of an imaging device according to the first embodiment.
Of the functional blocks shown in FIG. 1, for functions realized by software, a program for providing the function of each functional block is stored in a memory such as a ROM (Read Only Memory). Then, the program is read into a RAM (Random Access Memory) and executed by a CPU (Central Processing Unit). For the functions realized by hardware, for example, by using a predetermined compiler, a dedicated circuit may be automatically generated on the FPGA from a program for realizing the function of each functional block. FPGA is an abbreviation for Field Programmable Gate Array. Also, a gate array circuit may be formed in the same manner as the FPGA and implemented as hardware. Also, it may be realized by an ASIC (Application Specific Integrated Circuit). Note that the configuration of the functional blocks shown in FIG. 1 is an example, and a plurality of functional blocks may constitute one functional block, or one of the functional blocks may be divided into blocks that perform a plurality of functions. good too.

In FIG. 1 , an imaging device 11 includes an imaging unit 12 , an image processing unit 13 , an imaging control unit 14 , a network processing unit 15 , a system control unit 16 and an authentication unit 17 . The imaging control unit 14 includes an authentication target detection unit 14a, an authentication area setting unit 14b, an exposure time adjustment unit 14c, and a brightness average calculation unit 14d. The imaging unit 12 includes a lens group 12a, an imaging element 12b, and an amplifier 12c. The imaging device 11 is connected to a client device (not shown) via a network 18 .

The imaging unit 12 performs imaging based on the light from the subject. The lens group 12a collects light from a subject on the light receiving surface of the imaging device 12b. Although only one lens is shown in FIG. 1, a plurality of lenses may be provided, and may include, for example, a zoom lens, a focus lens, and a blur correction lens. The imaging element 12b converts light from a subject into an electric signal for each pixel and outputs the electric signal. The imaging element 12b can change the exposure time for each divided area obtained by dividing the image into a plurality of areas. A divided area can be composed of one or more pixels. The imaging element 12b is, for example, a semiconductor element such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor and peripheral circuits. The amplifier 12c amplifies the electrical signal output from the imaging device 12b and outputs an imaging signal.

The image processing unit 13 receives an imaging signal from the imaging unit 12, performs image processing such as development processing in a video processing unit (not shown), and generates a captured image. For example, the image processing unit 13 converts the imaging signal from the imaging unit 12 into digital data by A/D conversion, and then performs signal processing including demosaicing processing, white balance processing, gamma processing, and the like to generate a digital image. Generate.

The imaging control unit 14 drives the lens group 12a for zooming and focusing, controls the gain and exposure time for each region of the imaging element 12b, and causes the imaging element 12b to perform imaging at designated timing. do. At this time, the imaging control unit 14 adjusts the exposure time for each of the first region including the authentication target detected from the captured image and the second region where the authentication target is not detected, and Each exposure amount can be optimized. In addition, the imaging control unit 14 can skip adjusting the exposure times of the first area and the second area when the authentication target is not included in the captured image that has undergone exposure correction over the entire imaging range. The imaging control unit 14 can set an authentication area including an authentication target as the first area. The imaging control unit 14 can set a non-authentication area that does not include an authentication target as the second area, and the non-authentication area is, for example, a background area such as scenery. Alternatively, the imaging control unit 14 may set the entire image before detection of the authentication target as the second area. The whole image before detection of the authentication target may or may not include the authentication target.

Here, for the first area, the imaging control unit 14 can adjust the exposure time of the first area so that the feature points to be authenticated can be accurately detected during authentication. In addition, for the second area, for example, when the captured image is used as a monitoring image, the imaging control unit 14 controls the second area so that the subject can be visually recognized even in an environment where areas with high illuminance and areas with low illuminance coexist. The exposure time of the two areas can be adjusted. For example, for the second region, the imaging control unit 14 captures a region with high illuminance with a short exposure time and captures a region with low illuminance with a long exposure time. Either subject in the area can be visible.

The authentication target detection unit 14a detects an authentication target from the captured image. As a method of detecting an authentication target, for example, in face authentication, there is a method of detecting a shape such as a contour characteristic of a face. The object to be authenticated and its detection method may be other than this.
The authentication area setting unit 14b sets an authentication area including an authentication target in the captured image. At this time, the authentication area setting unit 14b can set the authentication area in units of divided areas obtained by dividing the captured image. Further, the authentication area setting unit 14b can move the authentication area on the captured image based on the amount and direction of movement of the object to be authenticated. The authentication area setting unit 14b can reset the authentication area on the captured image when the size of the authentication object changes.

The brightness average calculator 14c calculates the brightness value of the captured image and calculates an exposure correction value for optimizing the exposure amount of the captured image. At this time, if the authentication area is set in the captured image, the average brightness calculation unit 14c calculates the average brightness of each of the authentication area and the non-authentication area, and performs the authentication based on the average brightness of each of the authentication areas and the non-authentication area. An exposure correction value can be calculated for each of the area and the non-authentication area.

The exposure time adjustment unit 14d adjusts the exposure time according to the exposure correction value calculated by the luminance average calculation unit 14. FIG. At this time, when the authentication area is set in the captured image, the exposure time adjustment unit 14d adjusts the exposure time of each of the authentication area and the non-authentication area according to the exposure correction value of each of the authentication area and the non-authentication area. can do.

The network processing unit 15 converts the captured image from the image processing unit 13 in compliance with the network protocol and distributes it to the network 18 .
The system control unit 16 includes a CPU and a memory, controls each component of the imaging device 11 in an integrated manner, and sets various parameters. At this time, the system control unit 16 comprehensively controls the imaging unit 12, the image processing unit 13, the imaging control unit 14, and the network processing unit 15 so as to cooperate with each other.

The authentication unit 17 authenticates the authentication target detected from the captured image. At this time, the authentication unit 17 can authenticate the authentication target by confirming the consistency between the registered image registered in the authentication list and the authentication target detected from the captured image.

The network 18 is, for example, a local area network (LAN), and includes routers and the like that satisfy communication standards such as Ethernet (registered trademark). The imaging device 11 and a client device (not shown) are connected to a network 18 via a LAN cable or the like.

FIG. 2 is a diagram showing an example of a captured image during authentication according to the first embodiment. 2A shows a captured image 21A before exposure correction when the authentication target 24 does not exist, and FIG. 2B shows a captured image 21B after exposure correction when the authentication target 24 does not exist. FIG. 2C shows a captured image 21C before exposure correction when the authentication target 24 exists, and FIG. 2D shows a captured image 21D after exposure correction when the authentication target 24 exists. In FIGS. 2(C) and 2(D), a subject other than the background is set as the authentication target 24 .

In FIGS. 2(A) and 2(C), if an image is captured without exposure correction, the exposure is not appropriate, resulting in captured images 21A and 21C that include an underexposed area and an overexposed area. Even if the authentication target 24 exists in the captured images 21A and 21C with inappropriate exposure, the authentication target 24 may not be detected.

Therefore, the imaging control unit 14 in FIG. 1 performs exposure correction so that the entire imaging range is optimally exposed. At this time, as shown in FIGS. 2(B) and 2(D), captured images 21B and 21D in which the exposure amount is optimized over the entire imaging range are obtained. The authentication target detection unit 14a in FIG. 1 checks whether or not there is an authentication target 24 in each of the captured images 21B and 21D with the appropriate exposure amount. Although the method of detecting the authentication object 24 differs depending on the authentication to be performed, the authentication object detection unit 14a can determine whether or not the authentication object 24 exists in the exposure-corrected captured images 21B and 21D. At this time, the authentication target detection unit 14a can determine that the authentication target 24 does not exist in the captured image 21B, and can determine that the authentication target 24 exists in the captured image 21D.

FIG. 3 is a diagram showing an example of luminance values of a captured image during authentication according to the first embodiment. 3A shows the luminance values within the frame 22A of the captured image 21A of FIG. 2A, and FIG. 3B shows the luminance values within the frame 22B of the captured image 21B of FIG. 2B. indicate a value.

In FIG. 3A, in the captured image 21A of FIG. 2A, the luminance value is below the appropriate value in the range from 0 to X1 in the direction of the X axis 23, and the luminance value is above the appropriate value in the range from X1 to X2. .
For this reason, the imaging control unit 14 performs exposure correction for each area in the direction of increasing the luminance value in the range from 0 to X1 in the direction of the X axis 23, and performs exposure compensation for each area in the direction of decreasing the luminance value in the range from X1 to X2. Make corrections. As a result, as shown in FIG. 3(B), the captured image 21B of FIG. 2(B) is obtained in which the luminance value has been corrected to an appropriate value over the range of 0 to X2.

FIG. 4 is a diagram showing an example of a captured image and luminance values after authentication area setting according to the first embodiment. 4A shows a captured image 21D after setting the authentication area 31 and the background area 32, and FIG. 4B shows a captured image 21E after performing exposure correction on the authentication area 31 and the background area 32. show. FIG. 4(C) shows luminance values within the frame 22E of the captured image 21E of FIG. 4(B).

In FIG. 4A, when the authentication target 24 is detected from the captured image 21D, the authentication region setting unit 14b sets the authentication region 31 including the authentication target 24 and the background region 32 not including the authentication target 24 to the captured image 21D. split the The authentication area 31 can be a predetermined range around the authentication target 24 , and the background area 32 can be an area other than the authentication area 31 . The predetermined range around the authentication area 31 may be changed depending on the authentication target.

Next, the brightness average calculation unit 14c calculates the brightness average value of each of the authentication area 31 and the background area 32, and sets an exposure correction value. Then, the exposure time adjustment unit 14d adjusts the exposure time based on the exposure correction value, and captures an exposure-corrected image for each of the authentication region 31 and the background region 32, thereby obtaining the captured image of FIG. 21E is obtained. Although the captured image 21E in FIG. 4B shows the case where the exposure is set so that the authentication area 31 is not subjected to exposure correction, the exposure setting of the authentication area 31 is not limited to this.

At this time, as shown in FIG. 4C, since the range from 0 to X3 in the direction of the X-axis 23 in FIG. below. Since the range from X3 to X2 corresponds to the background area 32, the brightness value is a proper value.

Here, in the authentication area 31 of the captured image 21E in FIG. 4B, by not performing exposure correction, the authentication area 31 is exposed under the influence of the luminance value of the area other than the authentication area 31. Underexposure and overexposure can be prevented. Therefore, it is possible to prevent the gradation of the authentication area 31 from being distorted due to the exposure correction of the authentication area 31 and the deterioration of the accuracy of extracting the feature points of the authentication target 24, thereby preventing the deterioration of the authentication accuracy. can do.

On the other hand, in the captured image 21D of FIG. 4A, the brightness value is optimized so that the authentication target 24 can be easily gazed at by performing exposure correction on the entire imaging region including the authentication region 31. can be done. Therefore, the accuracy of monitoring the authentication target 24 in the captured image 21D can be improved, and the extraction accuracy of the authentication target 24 can be improved.

FIG. 5 is a diagram showing an example of a captured image when the authentication area is moved according to the first embodiment. 5A shows a captured image 21F before the authentication target 24 is moved, and FIGS. 5B and 5C show captured images 21G and 24H after the authentication target 24 is moved.

In FIG. 5A, when setting the authentication area 31 and the background area 32, the authentication area setting unit 14b sets moving object detection areas 41 to 43 around the authentication target 24 in the captured image 21F. The authentication area setting unit 14b may change the sizes and positions of the moving object detection areas 41 to 43 according to the authentication object 24. FIG.

As shown in FIG. 5B, the authentication area setting unit 14b does not detect a moving object in the moving object detection areas 41 and 43, but detects a moving object in the moving object detection area 42 in the captured image 21G in which the authentication object 24 has moved. shall be At this time, the authentication area setting unit 14b determines that the authentication target 24 has moved in the X2 direction of the X axis 23, and places the authentication area 31 and the moving object detection areas 41 to 43 on the captured image 21G by the same amount as the moving amount of the moving object. to move.

As shown in FIG. 5C, the authentication area setting unit 14b does not detect a moving object in the moving object detection areas 41 and 42, but detects a moving object in the moving object detection area 43 in the captured image 21H in which the authentication target 24 has moved. shall be At this time, the authentication area setting unit 14b determines that the authentication target 24 has moved in the Y1 direction of the Y axis 44, and places the authentication area 31 and the moving body detection areas 41 to 43 on the captured image 21G by the same amount as the moving amount of the moving body. to move.

When the size of the authentication object 24 changes due to the movement of the authentication object 24, the authentication area setting unit 14b divides the authentication area 31 and the background area 32 again. For example, as shown in FIG. 5C, when the authentication target 24 moves to the back of the captured image 21H, the size of the subject becomes smaller. The captured image 21H is subdivided into .

Here, the authentication area setting unit 14b moves the authentication area 31 so as to follow the movement of the authentication object 24, thereby optimizing the exposure amount of the authentication object 24 even when the authentication object 24 moves. It is possible to prevent deterioration of authentication accuracy.

FIG. 6 is a diagram showing an example of a captured image when there are multiple authentication areas according to the first embodiment. 6A shows a captured image 21J in which the authentication targets 24 and 51 are separated from each other, and FIG. 6B shows a captured image 21K in which the authentication targets 24 and 51 are close to each other.

6A and 6B, when there are a plurality of authentication targets 24 and 54, the authentication area setting unit 14b determines whether the distance between the authentication targets 24 and 54 is equal to or less than a predetermined value. Then, the authentication area setting unit 14b changes the setting method of the authentication area according to the distance between the authentication targets 24 and 54. FIG. For example, based on the distance between the authentication targets 24 and 54, the authentication area setting unit 14b can determine whether the authentication targets 24 and 54 are independent or overlapping.

As shown in FIG. 6A, when each of the authentication targets 24 and 54 is independent, the authentication region setting unit 14b individually sets the authentication regions 31 and 51 for each of the authentication targets 24 and 54 on the captured image 21J. set. Thereby, the exposure correction can be optimized for each of the authentication areas 31 and 51, and the authentication accuracy of each of the authentication targets 24 and 54 can be improved.

On the other hand, as shown in FIG. 6B, when the authentication targets 24 and 54 overlap each other, the authentication region setting unit 14b sets an authentication region 55 including the authentication targets 24 and 54 in the captured image 21K. As a result, the exposure correction can be optimized for the overlapping portions of the authentication targets 24 and 54, and a decrease in authentication accuracy of the authentication targets 24 and 54 can be suppressed.

FIG. 7 is a flow chart showing the imaging control method according to the first embodiment.
Each step in FIG. 7 is realized by the imaging control unit 14 reading and executing a program stored in the storage unit of the imaging apparatus 11 in FIG. Also, at least part of the flowchart shown in FIG. 7 may be implemented by hardware. When implemented by hardware, for example, by using a predetermined compiler, a dedicated circuit may be automatically generated on an FPGA from a program for implementing each step. Also, a Gate Array circuit may be formed in the same manner as the FPGA and implemented as hardware. Also, it may be realized by an ASIC.
In this case, each block in the flowchart shown in FIG. 7 can be regarded as a hardware block. A plurality of blocks may be collectively configured as one hardware block, or one block may be configured as a plurality of hardware blocks.

In step S61 of FIG. 7, the imaging control unit 14 of FIG. 1 performs exposure correction for the entire imaging range.
Next, in step S<b>62 , the imaging control unit 14 acquires from the image processing unit 13 a captured image whose exposure has been corrected for the entire imaging range.
Next, in step S63, the imaging control unit 14 checks whether there is an authentication target in the captured image. When the authentication target does not exist in the captured image, the imaging control unit 14 skips the processing of steps S64 to S66 and terminates the processing.

On the other hand, if there is an authentication target in the captured image, the imaging control unit 14 proceeds to step S64 and sets the authentication area and the background area in the captured image.
Next, in step S65, the imaging control unit 14 calculates exposure correction values for each of the authentication area and the background area based on the luminance average values of the authentication area and the background area.
Next, in step S<b>66 , the image capturing control unit 14 performs image capturing according to the exposure correction values of the authentication area and the background area, and acquires the captured image from the image processing unit 13 .

As described above, according to the first embodiment described above, the imaging control unit can adjust the exposure time of each of the first area including the authentication target and the second area where the authentication target is not detected. . Therefore, the imaging control unit can optimize the exposure correction of each of the first area and the second area, and can improve the detection accuracy of the authentication target from the image. Accuracy can be improved.

<Second embodiment>
FIG. 8 is a diagram showing an example of a captured image and luminance values after authentication area setting according to the second embodiment. This second embodiment shows a case where the authentication object 74 is a face image. Note that FIG. 8A shows a photographed image 71D after setting the face authentication area 71 and the face background area 72, and FIG. A captured image 71E is shown. FIG. 8(C) shows luminance values within a frame 72E of the captured image 71E of FIG. 8(B).

In FIG. 8A, when the authentication target 74 is detected from the captured image 71D, the authentication region setting unit 14b of FIG. The captured image 71 D is divided into 72 . The face authentication area 71 can be a predetermined range around the face image, and the face background area 72 can be an area other than the face authentication area 71 .

Next, the brightness average calculation unit 14c calculates the brightness average value of each of the face authentication area 71 and the face background area 72, and sets an exposure correction value. Then, the exposure time adjustment unit 14d adjusts the exposure time based on the exposure correction value, and captures an exposure-corrected image for each of the face authentication area 71 and the face background area 72, thereby obtaining the image shown in FIG. 8B. A captured image 71E is obtained. Although the captured image 71E in FIG. 8B shows the case where the exposure is set so that the exposure of the face authentication area 71 is not corrected, the exposure setting of the face authentication area 71 is not limited to this.

At this time, as shown in FIG. 8C, the range from 0 to X4 in the direction of the X-axis 23 in FIG. below the value. Since the range from X4 to X2 corresponds to the face background area 72, the luminance value is an appropriate value.

FIG. 9 is a diagram showing an example of a captured image when the authentication area is moved according to the second embodiment.
9A shows a captured image 71F before the authentication target 74 is moved, and FIGS. 9B and 9C show captured images 71G and 74H after the authentication target 74 is moved. show.

In FIG. 9A, when the face authentication region 71 and the face background region 72 are set, the authentication region setting unit 14b sets moving object detection regions 81 to 84 around the authentication target 74 in the captured image 71F. The authentication area setting unit 14b may change the sizes and positions of the moving object detection areas 71 to 74 depending on the authentication target 74. FIG.

As shown in FIG. 9B, the authentication area setting unit 14b does not detect a moving object in moving object detection areas 81, 83, and 84, and detects a moving object in a moving object detection area 82 in a captured image 71G in which an authentication target 74 has moved. shall be detected. At this time, the authentication area setting unit 14b determines that the authentication object 74 has moved in the X2 direction of the X axis 23, and places the authentication area 71 and the moving object detection areas 81 to 84 on the captured image 71G by the same amount as the moving amount of the moving object. to move.

As shown in FIG. 9C, the authentication area setting unit 14b does not detect a moving object in moving object detection areas 81, 82, and 84, and detects a moving object in a moving object detection area 83 in a captured image 71H in which an authentication target 74 has moved. shall be detected. At this time, the authentication area setting unit 14b determines that the authentication object 74 has moved in the Y1 direction of the Y axis 44, and sets the face authentication area 71 and the moving object detection areas 81 to 84 by the same amount as the amount of movement of the moving object in the captured image 71G. move up.

When the size of the authentication object 74 changes due to the movement of the authentication object 74, the authentication area setting unit 14b divides the face authentication area 71 and the face background area 72 again. For example, as shown in FIG. 9C, when the authentication target 74 moves to the back of the captured image 71H, the size of the face image becomes smaller. The captured image 71H is subdivided so that

FIG. 10 is a diagram showing an example of a captured image when there are multiple authentication areas according to the second embodiment. 10A shows a captured image 71J in which the authentication targets 74 and 94 are separated from each other, and FIG. 10B shows a captured image 71K in which the authentication targets 74 and 94 are close to each other.

10A and 10B, when there are a plurality of authentication targets 74 and 94, the authentication area setting unit 14b determines whether the distance between the authentication targets 74 and 94 is equal to or less than a predetermined value. Then, the authentication area setting unit 14b changes the setting method of the authentication area according to the distance between the authentication targets 74 and 94. FIG. For example, based on the distance between the authentication targets 74 and 94, the authentication area setting unit 14b can determine whether the authentication targets 74 and 94 are independent or overlapping.

As shown in FIG. 10A, when the authentication targets 74 and 94 are independent, the authentication region setting unit 14b sets the authentication regions 71 and 91 for the authentication targets 74 and 94, respectively, on the captured image 71J. set. On the other hand, as shown in FIG. 10B, when the authentication targets 74 and 94 overlap each other, the authentication region setting unit 14b sets an authentication region 95 including the authentication targets 74 and 94 in the captured image 71K.

As described above, according to the second embodiment described above, the imaging control unit can adjust the exposure time of each of the first area including the face image and the second area where the face image is not detected. . Therefore, the imaging control unit can optimize the exposure correction of each of the first area and the second area, thereby improving the detection accuracy of the face image from the image, and improving the face authentication accuracy. can be improved.

<Third Embodiment>
11A and 11B are diagrams illustrating examples of captured images before and after authentication according to the third embodiment. Note that FIGS. 11A and 11B are captured images in which an authentication target that matches a subject registered in the authentication list 101 exists, and FIGS. 11C and 11D are the authentication list 101 shows a captured image in which there is no authentication target that matches the subject registered in 101. FIG.

In FIG. 11A, a face authentication area 71 including an authentication target 74 is set in a captured image 71D. Then, the authentication unit 17 confirms whether or not a subject that matches the authentication target 74 included in the face authentication area 71 is registered in the authentication list 101 . After confirming that the subject 102 matching the authentication target 74 included in the face authentication area 71 is registered in the authentication list 101, the authentication unit 17 completes the authentication. In this case, the image capturing control unit 14 captures an image of the face recognition area 71 without exposure correction after authentication. That is, the imaging control unit 14 adjusts the exposure time of the face authentication area 71 based on the average luminance value of the face authentication area 71 after authentication. At this time, as shown in FIG. 11(B), a photographed image 71E in which only the face background area 72 is subjected to exposure correction is obtained in photographing after authentication.

In FIG. 11C, a face authentication area 111 including an authentication target 114 is set in the captured image 71L. Then, the authentication unit 17 confirms whether or not a subject that matches the authentication target 114 included in the face authentication area 111 is registered in the authentication list 101 . Assume that the authentication unit 17 has confirmed that the subject matching the authentication target 114 included in the face authentication area 111 is not registered in the authentication list 101 . In this case, the imaging control unit 14 performs exposure correction of the face authentication area 111 after authentication so that the user can gaze at the authentication target 114 even after authentication. That is, the imaging control unit 14 adjusts the exposure time of the face authentication area 111 based on the average luminance value of the entire image after authentication. At this time, as shown in FIG. 11D, in the post-authentication imaging, similarly to the pre-authentication imaging, a captured image 71L in which the face authentication area 111 and the face background area 72 are exposure-corrected is obtained.

As described above, according to the third embodiment described above, the imaging control unit changes the exposure setting of the authentication area according to the authentication result after authentication of the authentication target. Thereby, the imaging control unit can improve the visibility of the authentication target and improve the authentication accuracy of the authentication target according to the authentication result.

<Other embodiments>
12 is a block diagram illustrating a hardware configuration example of an imaging control unit according to the embodiment; FIG.

12, the imaging control section 14 includes a processor 131, a communication control section 132, a communication interface 133, a main storage section 134, an auxiliary storage section 135, and an input/output interface 137. FIG. Processor 131 , communication control unit 132 , communication interface 133 , main storage unit 134 , auxiliary storage unit 135 and input/output interface 137 are interconnected via internal bus 136 . Main memory 134 and auxiliary memory 135 are accessible from processor 131 .

Also, an input device 140 and a display device 141 are provided outside the imaging control unit 14 . Input device 140 and display device 141 are connected to internal bus 136 via input/output interface 137 . The input device 140 is, for example, a keyboard, mouse, touch panel, card reader, voice input device, or the like. The display device 141 is, for example, a liquid crystal monitor, an organic EL display, or a micro LED display.

The processor 131 controls the operation of the imaging control unit 14 as a whole. The processor 131 may be a CPU or a GPU (Graphics Processing Unit). Processor 131 may be a single-core processor or a multi-core processor. Processor 131 may include a hardware circuit (eg, FPGA or ASIC) such as an accelerator that speeds up some of the processing.

The main storage unit 134 can be composed of a semiconductor memory such as an SRAM (Static Random Access Memory) or a DRAM (Dynamic Random Access Memory). The main storage unit 134 can store a program being executed by the processor 131 and can provide a work area for the processor 131 to execute the program.

The auxiliary storage unit 135 is a non-volatile storage device, such as a ROM, hard disk device, or SSD (Solid State Drive). The auxiliary storage unit 135 can hold executable files of various programs and data used for executing the programs.

The communication control unit 132 is hardware having a function of controlling communication with the outside. Communication control unit 132 is connected to network 139 via communication interface 133 . The network 139 may be the Internet, a WAN, a LAN such as WiFi or Ethernet (registered trademark), or a mixture of the Internet, WAN, and LAN.

The input/output interface 137 converts data input from the input device 140 into a data format processable by the processor 131, and converts data output from the processor 131 into a data format processable by the display device 141. .

The processor 131 can implement the processing in FIG. 7 by reading the program stored in the auxiliary storage unit 135 to the main storage unit 134 and executing the program.
Execution of the program for realizing the processing in FIG. 7 may be shared among a plurality of processors or computers. Alternatively, the processor 131 may instruct a cloud computer or the like via the network 139 to execute all or part of the program for realizing the processing of FIG. 7, and receive the execution result.

The present invention may supply a program that implements one or more functions of the above-described embodiments to a system or device via a network or storage medium. One or more functions of the above-described embodiments can also be realized by a process in which one or more processors in the computer of the system or device read and execute the program. It can also be implemented in a circuit (eg FPGA or ASIC) that implements one or more functions.

11 imaging device, 12 imaging unit, 13 image processing unit, 14 imaging control unit, 14a authentication target detection unit, 14b authentication target setting output unit, 14c luminance average calculation unit, 14d exposure time adjustment unit, 15 network processing unit, 16 system control unit

Claims (13)

detection means for detecting an authentication target from an image;
setting means for setting, in the image, a first area including the authentication target detected by the detection means;
adjusting means for adjusting the exposure time of each of the first area set by the setting means and the second area in which the authentication target is not detected;
An imaging control device comprising: Further comprising calculating means for calculating an average luminance value of each of the first region and the second region,
The adjusting means adjusts the exposure time of the first region based on the average luminance value of the first region, and adjusts the exposure time of the second region based on the average luminance value of the second region. 2. The imaging control device according to claim 1, wherein: 3. The imaging control apparatus according to claim 1, wherein the setting unit moves the first area based on the amount and direction of movement of the authentication object. 4. The imaging control apparatus according to any one of claims 1 to 3, wherein the setting unit resets the first area when the size of the authentication object changes. 5. The first area according to any one of claims 1 to 4, wherein when said detecting means detects a plurality of authentication objects from said image, said setting means sets said first area based on a distance between said objects to be authenticated. 1. The imaging control device according to item 1. when the distance between the authentication targets is equal to or less than a predetermined value, the setting means sets the first region including the plurality of authentication targets;
6. The imaging control apparatus according to claim 5, wherein when the distance between the authentication targets exceeds a predetermined value, the setting unit sets the first area for each of the plurality of authentication targets. When the authentication object is detected from the image whose exposure has been corrected over the entire imaging range, the adjusting means adjusts the first area and the second area so that the respective exposure amounts of the first area and the second area are optimized. 7. The imaging control device according to any one of claims 1 to 6, wherein the exposure time of each of the second regions is adjusted. 2. When the authentication target is not detected from the image whose exposure has been corrected over the entire imaging range, the adjustment means skips the adjustment of the exposure time of each of the first area and the second area. 8. The imaging control device according to any one of 7. When an authentication target that matches the registered image is detected, the adjustment means adjusts the exposure time of the first area based on the average luminance value of the first area after authentication,
9. The method according to any one of claims 1 to 8, characterized in that, when an authentication target that matches the registered image is not detected, the adjustment means adjusts the exposure time of the first area based on an average luminance value of the entire image after authentication. The imaging control device according to any one of claims 1 to 3. 10. The imaging control apparatus according to any one of claims 1 to 9, wherein the authentication target is a face image. 11. The imaging control apparatus according to any one of claims 1 to 10, wherein the second area is an entire image of the authentication target before detection or a background image that is a background of the authentication target. a step of detecting an authentication target from an image;
setting a first area including the authentication target in the image;
adjusting the exposure time of each of the first region and the second region where the authentication target is not detected;
An imaging control method comprising: A program for operating a computer as the imaging control device according to any one of claims 1 to 11.

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