JPH11327038A - Image pickup unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a constitution and also to mitigate a mounting condition by dispensing with a range-finding means or the like to obtain the displacement quantity of a narrow area photographing camera. SOLUTION: An optical mechanism part 50 is provided so as to set optical axes of a wide area photographing camera 10 and the narrow area photographing camera 30 coaxial. Then, when a wide area image is obtained by the wide area photographing camera 10, image processing is executed by a wide area image processing part 20, and the displacement quantity to such a target position that the narrow area photographing camera 30 executes photographing is obtained. The mirror 52 of the optical mechanism part 50 is driven by a driving part 80 based on the displacement quantity obtained so as to set the target position on the optical axis of the narrow area photographing camera 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in, for example, an iris recognition device, and captures a wide-area photographing camera for photographing an image of a wide area of the upper body including the head of a target user, and a photographer's eyes. The present invention relates to an imaging apparatus having a narrow-area imaging camera.

[0002]

2. Description of the Related Art Conventionally, in an imaging device used for an iris recognition device or the like, first, a region including a user's head is photographed by a wide-area photographing camera, and the user's head and eyes are taken out of the photographed image. The position is detected, and the iris is photographed by pointing the narrow-area photographing camera to the position of the eye (target position).

[0003]

In the above-mentioned conventional imaging apparatus, the wide-area photographing camera and the narrow-area photographing camera are configured from independent viewpoints.

FIG. 2 is an explanatory view of the configuration of a conventional wide-area camera and a narrow-area camera. As shown in the figure, the wide-area photographing camera 100 and the narrow-area photographing camera 200 are installed in parallel with respect to the front (toward the subject).
, A driving mechanism 300 for driving the driving mechanism is provided. Reference numeral 400 denotes a front panel provided on the front side of the wide area photographing camera 100 and the narrow area photographing camera 200.

[0005] Since the conventional device has such a configuration,
In order to obtain the displacement angle θ of the narrow-area photographing camera 200 given to the drive mechanism unit 300 for photographing the target, it is necessary to obtain an appropriate displacement from target position information calculated from images acquired by the wide-area photographing camera 100. Conversion using a reference table or the like was required.

FIG. 3 is an explanatory diagram of this. (B) in the figure
Indicates a case where the target is close, and (c) indicates a case where the target is far. In the situations (b) and (c), when the target is photographed, the position of the target image in the wide area image acquired by the wide area camera (W-CAM) is the same. That is, the image shown in FIG.

[0007] However, the displacement for moving the N-CAM to photograph a target is as follows.
It is different from θ1 in the case of (b) and θ2 in the case of (c).

That is, the displacement angle θ of the narrow-area photographing camera uses the target position (x, y) and the target position (z) in the wide-area image as parameters (θ = F ((x, y),
z)). Therefore, in order to obtain the displacement angle θ, a distance measuring means is required as an apparatus, and further, conversion from a target position (x, y) and a target position (z) in a wide area image by a correspondence reference table or the like is required. there were.

Conventionally, since the angle of view of a wide-area photographing camera is fixed, there is a problem that a target position cannot be calculated depending on the state of an image.

FIG. 4 is an explanatory diagram of this. As shown in the figure, when there is a target user at the position A in the angle of view of the wide-area photographing camera and the directional range of the narrow-area photographing camera, even if the iris is in the photographable range of the narrow-area photographing camera. Regardless, in the image taken by the wide area camera, the person was not completely within the angle of view. . That is, although the persons at the positions B and C show the range in which the target position can be detected, the person at the position A has the iris in spite of the iris.
Since the range in which the target position can be detected is not shown, the displacement angle of the narrow-area camera cannot be obtained.

In order to solve such a problem, a method of enlarging a photographing range by using a wide-angle photographing camera as a wide-angle lens can be considered. However, in such a method, a sufficient image quality is usually obtained at the center of the screen. However, distortion is likely to occur at the periphery of the screen. Therefore, enlargement of the angle of view by such a method has been insufficient.

Further, since the optical axes of the wide-area photographing camera 100 and the narrow-area photographing camera 200 are independent of each other, for example, the mounting of the wide-area photographing camera
There are restrictions on the mounting conditions such that 0 and the width of the narrow area photographing camera 200 are necessarily required.

[0013] From such a point, in order to calculate the displacement angle of the narrow-area photographing camera, the structure can be simplified without the need for a structure such as a distance measuring means or a correspondence reference table, and the imaging device having a gradual mounting condition can be realized. Realization was desired. In addition, it has been desired to realize an imaging device that can enlarge the angle of view of a wide-area image and obtain sufficient image quality.

[0014]

The present invention employs the following structure to solve the above-mentioned problems. <Structure of Claim 1> A wide-area photographing camera that acquires an image of a subject, a narrow-area photographing camera that acquires an image of a smaller area than the wide-area photographing camera, and a subject, and the wide-area photographing camera and the narrow-area photographing camera An optical mechanism for setting the optical axis of the wide-area photographing camera and the optical axis of the narrow-area photographing camera to be coaxial, and changing the photographing angle of the narrow-area photographing camera with respect to a subject; and an image acquired by the wide-area photographing camera. A wide-area image processing unit that calculates a target position of the narrow-area imaging camera from the target position and calculates an imaging angle to the target position; and an optical axis and a target position of the narrow-area imaging camera based on the imaging angle calculated by the wide-area image processing unit. And a drive section for driving the optical mechanism section so that the values match.

<Structure of Claim 2> In the image pickup apparatus according to Claim 1, a drive section for driving the optical mechanism section by a predetermined photographing angle so as to have a predetermined photographing range exceeding the angle of view of the wide-area photographing camera. And a wide-area image processing unit that calculates a target position of the narrow-area imaging camera based on an image of the wide-area imaging camera obtained by driving the optical mechanism unit.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. << Specific Example >> This specific example shows a case where the present invention is applied to an iris recognition device as an imaging device.

<Configuration> FIG. 1 is a configuration diagram showing a specific example of an imaging apparatus according to the present invention. The device shown is a wide-area photographing camera 1
0, a wide area image processing section 20, a narrow area photographing camera 30, a narrow area image processing section 40, an optical mechanism section 50, a front panel 60, a control section 70, and a drive section 80.

The wide-area photographing camera 10 is used by a user (subject).
In order to detect the position of the head and eyes of the camera 1, the camera captures a wide range of the upper body of the user 1 via the front panel 60 and the optical mechanism 50. Wide area image processing unit 20
Is a processing unit that analyzes the image of the user 1 captured by the wide-area camera 10 and detects the head / eye position. That is, the wide area image processing unit 20 calculates the target position of the narrow area shooting camera 30 from the image shot by the wide area shooting camera 10,
This is a processing unit that calculates the amount of displacement (imaging angle) to the target position.

The narrow-area photographing camera 30 is a camera for photographing an eye, which is a target position of the user 1, via the front panel 60 and the optical mechanism 50. Narrow image processing unit 4
Reference numeral 0 denotes a processing unit that analyzes an image captured by the narrow-area imaging camera 30 and performs iris recognition processing.

The optical mechanism 50 has a function of aligning the optical axis of the wide-area photographing camera 10 with the optical axis of the narrow-area photographing camera 30 and directing the same toward a target direction.
2. A half mirror 53 is provided. The lens 51 is a lens for setting the photographing range of the wide area photographing camera 10 and the narrow area photographing camera 30 via the mirror 52 and the half mirror 53 to a predetermined value. The mirror 52 includes a driving unit 80
Is a mirror driven by the
And it is installed so as to be rotatable in the left-right direction and the up-down direction with respect to the optical axis of the narrow-area photographing camera 30. The half mirror 53 reflects the image of the user 1 reflected by the mirror 52 toward the wide-area photographing camera 10 and the narrow-area photographing camera 3.
This is a mirror that transmits light with respect to 0. The front panel 60 is a panel provided on the front of the optical mechanism unit 50.

The control section 70 is a control section for controlling each section including the wide area image processing section 20, the narrow area image processing section 40 and the drive section 80.

The driving section 80 has a function of driving the optical mechanism section 50 based on the displacement calculated by the wide area image processing section 20 so that the optical mechanism section 50 becomes the target position of the narrow area photographing camera. That is, the driving unit 80 has a function of driving the mirror 52 of the optical mechanism unit 50 based on the displacement angle calculated by the wide-area image processing unit 20 so that the optical axis of the narrow-area imaging camera 30 matches the target position. doing.

The wide-area photographing camera 10, the narrow-area photographing camera 30, the optical mechanism 50, the front panel 60, and the driving unit 80 are provided in an optical unit (not shown). Processing unit 40 and control unit 7
0 is provided in the personal computer. Each function of the wide area image processing unit 20, the narrow area image processing unit 40, and the control unit 70 is realized by the microprocessor executing a program for performing image processing and drive control.

<Operation> FIG. 5 is a flowchart showing the operation of this embodiment. When the iris recognition operation is started, first, a wide-area camera image is acquired by the wide-area photographing camera 10 (step S1). Thereby, the wide area image processing unit 20 analyzes the wide area camera image and sets the target position (x, y).
Is determined (step S2). Here, the target position (x,
Since the determination of y) is not directly related to the characteristic points of this specific example, it will be briefly described.

FIG. 6 is an explanatory diagram of eye position detection by template matching. As shown in the figure, the face template is matched based on the arrangement relationship, shape, and the like of the dark and light portions of the face, and the position of the eyes is detected. In the illustrated example, the area A is the target position.

In step S2, the target position (x,
When y) is determined, next, the drive displacement θ of the narrow-area photographing camera 30 is determined. Here, displacement θ = (θx, θy) is
It can be obtained from the xy axis center position (x0, y0) of the wide area image and the target position (x, y) of the wide area image by the following equation.

Θ = (θx, θy) = F (x0−x, y0−y) θx = Wx (x0−x), θy = Wy (y0−y) where Wx is the weight of the displacement in the x-axis direction, Wy indicates the weight of the displacement in the y-axis direction.

The wide area image processing section 20 controls the narrow area photographing camera 3
When the drive displacement θ of 0 is obtained, the drive unit 80 drives the optical mechanism unit 50 to have the obtained drive displacement (step S3). In other words, the target position (x, x) of the wide area image is on the optical axis of the narrow area camera 30 (= the optical axis of the wide area camera 10).
The mirror 52 is driven so that y) is positioned. Accordingly, it is not necessary to convert the target position information of the wide area image as the displacement information of the narrow area photographing camera 30, and the displacement amount of the narrow area photographing camera 30 can be used as it is.

When the optical mechanism section 50 is driven by the drive section 80, the narrow-area photographing camera 30 outputs the image of the eye of the user 1 (the narrow-area camera) via the front panel 60, the lens 51, the mirror 52, and the half mirror 53. Image) (step S4). Thus, the narrow-area image processing unit 40 performs the iris recognition process using the narrow-area camera image (Step S5). still,
Since the iris recognition process in step S5 is a known process, a description thereof will be omitted. If the result of the iris recognition processing in step S5 is NG, step S1
And a series of processing is repeated, and if the result is OK, the iris recognition processing ends.

<Effects> As described above, according to the specific example,
Since the optical axis of the wide-area photographing camera 10 and that of the narrow-area photographing camera 30 are arranged coaxially, and the image to the narrow-area photographing camera 30 is displaced by the optical mechanism section 50, the conventional measurement method is used. The distance information is not required, and the position information of the image obtained by the wide-area photographing camera 10 can be used as the displacement information of the narrow-area photographing camera 30 as it is.

In this example, since the wide-area image and the narrow-area image incident on the optical mechanism 50 are also coaxial, for example, the width of the wide-area camera and the narrow-area camera is set on the front panel as in the conventional case. Restrictions on mounting conditions, which are necessarily required, are also relaxed, and an imaging device with gradual mounting conditions can be realized.

<< Other Specific Examples >> In the above specific examples, the mirror 52 of the optical mechanism 50 is driven to displace the image to the narrow-area photographing camera 30. Therefore, the mirror 52 may be driven even when a wide-area camera image is obtained, so that a wide-area camera image may be obtained.

FIG. 7 is an explanatory diagram in the case of displacement when acquiring a wide area image. As shown in the drawing, the solid line frame is the angle of view of the wide area photographing camera 10, and this range corresponds to the photographing range of the conventional wide area photographing camera. On the other hand, when the wide area camera image is acquired by driving the mirror 52, a wider area can be photographed as shown by a thick broken line frame in the drawing. When obtaining an image as indicated by a thick broken line frame, a process of synthesizing a plurality of images captured by the wide area camera 10 is performed.

Therefore, the person at the position A, which was impossible in the related art, can detect the position of the eyes. Further, since the image is not an image formed by a wide-angle lens or the like, a high-quality image can be obtained over a wide range without causing distortion around the screen.

In the above example, the case where the image pickup apparatus is applied to an iris recognition apparatus has been described. However, the present invention is not limited to this, and the subject and image processing may be any. In addition, the optical mechanism 50 also includes a mirror 52
And the half mirror 53, the optical axes of the wide-area camera 10 and the narrow-area camera 30 are made coaxial, and
Any configuration may be used as long as the image of the subject can be displaced with respect to these optical axes.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a specific example of an imaging device of the present invention.

FIG. 2 is a configuration explanatory view of a conventional wide-area imaging camera and a narrow-area imaging camera.

FIG. 3 is an explanatory diagram of a problem relating to displacement of a conventional narrow-area imaging camera.

FIG. 4 is an explanatory diagram of a problem relating to conventional eye position detection.

FIG. 5 is a flowchart showing an operation in a specific example of the imaging device of the present invention.

FIG. 6 is an explanatory diagram of eye position detection processing in a specific example of the imaging apparatus of the present invention.

FIG. 7 is an explanatory diagram of another example of the imaging apparatus of the present invention when displaced during acquisition of a wide area image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 User (subject) 10 Wide-area imaging camera 20 Wide-area image processing unit 30 Narrow-area imaging camera 50 Optical mechanism unit 80 Drive unit

Claims (2)

[Claims] 1. A wide-area photographing camera for acquiring an image of a subject, a narrow-area photographing camera for acquiring an image in a smaller area than the wide-area photographing camera, and the subject, the wide-area photographing camera and the narrow-area photographing camera. An optical mechanism unit provided between the optical system unit, wherein an optical axis of the wide-area imaging camera and an optical axis of the narrow-area imaging camera are set to be coaxial, and an imaging angle of the narrow-area imaging camera with respect to the subject is variable; A wide-area image processing unit that calculates a target position of the narrow-area imaging camera from an image acquired by the imaging camera, and calculates an imaging angle to the target position; An imaging apparatus, comprising: a driving unit that drives the optical mechanism unit so that an optical axis of the area photographing camera coincides with a target position. 2. The image pickup apparatus according to claim 1, wherein the drive unit drives the optical mechanism unit by a predetermined photographing angle so as to have a predetermined photographing range exceeding the angle of view of the wide area photographing camera; A wide-area image processing unit for calculating a target position of the narrow-area imaging camera based on an image of the wide-area imaging camera obtained by driving the unit.