JP2003259190A - Automatic framing camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic framing camera which can speedily frame the face of a person. <P>SOLUTION: A pan operation is performed by a panning motor at a lower end in a tilt direction (S104 to 116) and the body axial position of a human body is found from signal variation by a range finding unit (light emitting element and light receiving element) capable of measuring a distance in one direction. Then a tilt operation is carried out by a tilting motor upwardly from the body axial position and the head end of the human body is found from signal variation by the range finding unit (S124 to 132). Then the tilt motor directs the photographic direction of a photographic lens to the center of the face of the found human body to frame the center of the face of the human body to the center of a field angle (S134 to 138) and the face of the human body is photographed by an imaging element. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic framing camera, and more particularly to an automatic framing camera that finds a person's face and automatically performs framing.

[0002]

2. Description of the Related Art In recent years, development of an authentication system for automatically authenticating a person based on image information of a person's face has been advanced. This system was devised in place of a key, PIN code input, fingerprint collation, etc. when a person who is allowed to enter a specific room enters the room, for example. It is simple and has a high degree of security because the person can be identified and the door unlocked just by standing in front of the door.

In such an authentication system, misjudgment can be prevented if the amount of image information required for authentication is large. Therefore, the camera is directed toward the person's face and the image is framed largely within the angle of view. In order to do that automatically, it is necessary to automatically frame the face of the person. An example of such an authentication camera is an automatic framing camera in which a photographing means for photographing a subject changes the photographing direction in a pan direction or a tilt direction to find the position (direction) of a person's face and photograph it.

[0004]

However, since the camera used in the above authentication system requires the face of the person to be faced, the processing time until the face of the person is searched for and framing is required unless the processing time is short. Entry into the above certification system is not quick.

In view of the above problems, it is an object of the present invention to provide an automatic framing camera that can quickly frame a person's face.

[0006]

In order to solve the above-mentioned problems, a first aspect of the present invention relates to a photographing means for photographing a subject, a distance measuring means for measuring a distance in one direction, and An automatic framing camera that includes a changing unit that integrally changes a shooting direction of a photographing unit and a distance measuring direction of the distance measuring unit, and pans at a lower end of a tilt direction by the direction changing unit in an automatic framing camera for framing and photographing a human face. An operation is performed to find the body axis of the person from the change in the distance information by the distance measuring means, and the direction changing means performs a tilting operation from the lower end or the upper end in the tilt direction of the body axis to change the distance information by the distance measuring means. By searching the top of the head of the person from, by lowering the shooting direction by a preset angle from the top of the searched head by the direction changing means,
It is characterized in that substantially the center of the face of the person is framed by the photographing means.

In the automatic framing camera of this aspect, the photographing means for photographing the object, the distance measuring means for measuring the distance in one direction, the photographing direction of the photographing means and the distance measuring direction of the distance measuring means are integrated. And a changing means for changing. In this aspect, the direction changing means performs the pan operation at the lower end of the tilt direction, the body axis of the person is searched for from the change of the distance information by the distance measuring means, and the direction changing means tilts from the lower end or the upper end in the tilt direction of the body axis. The top of the person's head is searched for from the change in the distance information by the distance measuring means, and the shooting direction is lowered by the preset angle from the top of the head found by the direction changing means, so that the face of the person's face is lowered. The approximate center is framed by the photographing means, and the face of the person is photographed by the photographing means. According to this aspect, the top of the person's head is searched next to the body axis of the person from the change in the distance information by the distance measuring means, and the photographing direction is lowered by a predetermined angle from the top of the head,
Since the approximate center of the person's face is framed, it is possible to quickly obtain an image of the person's face.

In order to solve the above-mentioned problems, a second aspect of the present invention is a photographing means for photographing a subject,
An automatic framing apparatus for framing a person's face is provided with a distance measuring means for measuring a distance in one direction and a changing means for integrally changing the photographing direction of the photographing means and the distance measuring direction of the distance measuring means. In the framing camera, a panning operation is performed at the lower end of the tilt direction by the direction changing means, and the body axis of the person is searched for from the change in distance information by the distance measuring means
The tilting operation is performed from the lower end or the upper end in the tilt direction of the body axis by the direction changing means, the top of the head of the person is searched from the change in the distance information by the distance measuring means, and the photographing direction of the photographing means is the distance measuring means. It is set to be lowered by a predetermined angle with respect to the distance measuring direction, so that the approximate center of the person's face is framed by the photographing means when the top of the person's head is searched. .

In this aspect, the direction changing means performs the pan operation at the lower end of the tilt direction, the body axis of the person is searched from the change of the distance information by the distance measuring means, and the direction changing means detects the lower end of the body axis in the tilt direction. The tilting operation is performed from the upper end, and the top of the person's head is found from the change in the distance information by the distance measuring means. Since the photographing direction of the photographing means is set to be lowered by a predetermined angle with respect to the distance measuring direction of the distance measuring means, when the top of the person's head is found, the approximate center of the person's face is framed by the photographing means. . According to this aspect, since the photographing direction of the photographing means is set lower than the distance measuring direction of the distance measuring means by the predetermined angle, the top of the head found by the direction changing means is set as in the first aspect. Therefore, it is not necessary to lower the photographing direction by a predetermined angle to frame the substantially central portion of the person's face on the photographing means, and the image of the person's face can be obtained more quickly than in the first aspect. Such a predetermined angle is t, for example, when the distance between the photographing means and the person is L1 and the distance from the approximate center of the person's face to the top of the person's head is L2.
It is given by an ⁻¹ (L2 / L1).

In the first and second aspects, the direction changeable range of the direction changing means is set in advance, and when the direction changing means performs pan drive at the lower end of the tilt direction, the distance measuring means can measure the distance. If is set to be shorter than the distance to the floor surface, the distance measuring means can find the body axis without misidentifying the floor surface as a person.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is applied to an automatic framing camera for automatically framing a human face will be described below with reference to the drawings.

(Construction) As shown in FIG. 1, a door 33 through which a person can enter and exit is provided on a wall surface (not shown). In the vicinity (left side) of the door 33, a person P standing in front of the door 33
An automatic framing camera (hereinafter, abbreviated as a camera) 1 for photographing the face of the person is arranged. On the upper side of the camera 1, a sticker 35 for instructing the person P to turn his or her face toward the camera 1 is attached to the wall surface. Also, the door 33
An authentication area 34 in which the camera 1 can photograph the face of the person P is defined in a rectangular shape on the floor surface in front of. Authentication area 3
A pressure switch (see reference numeral 31 in FIG. 4) capable of detecting the person P in the authentication area 34 is embedded in the floor surface of No. 4. The image information of the face of the person P captured by the camera 1 is
It is sent to a host unit (not shown) such as a personal computer through an interface (not shown). In the host unit, the image information of the face of the person P is processed in order to extract the data such as the feature amount of the face of the person P, and when it matches the feature amount of the person P accumulated in the database of the host unit. The door 33 is unlocked.

As shown in FIG. 2, the camera 1 includes a helmet-shaped casing 2a that covers a camera body, which will be described later.
A hemispherical hood 2b that covers the front opening of the casing 2a.
It has and. The casing 2a includes, for example, ABS.
A material such as (acrylonitrile butadiene styrene) can be used, and a material such as PC (polycarbonate) can be used for the hood 2b.

As shown in FIG. 3, the camera section main body has a first frame 7 made of sheet metal that supports the camera section main body and functions as a platform. The first frame 7 has a rectangular plate shape at the center, and has a protrusion bent upward at the center on the front side (of the camera body). An infrared LED 14 that emits (projects) infrared rays is provided on the front side of the protrusion.
Is fixed. On the other hand, a support member having an L-shaped cross section extends upward from a central portion of the first frame 7 on the opposite side (back side) from the protrusion.

A pan-direction supporting shaft for supporting the second frame 8 made of resin rotatably in the pan direction (horizontal direction) near the protrusion at the center of the first frame 7 and on the front side of the supporting member. 10 are respectively provided so as to project in the vertical direction, and the pan-direction support shaft 10 is pivotally supported by the central portion of the first frame and the support member. When viewed from the front side, the second frame 8 has a substantially quadrangular shape in which the first quadrant with the center of the front side as the origin is cut out.

Inside the second frame 8, a plate-shaped third frame 9 made of resin is arranged. At the center of the front side of the third frame 9, there is an image pickup device 4 such as a CCD, which is arranged at the focal position of the photographing lens 3 for photographing the face of the person P and which outputs an image by frame transfer or interline transfer. It is fixed. The taking lens 3 is usually
A fixed focus lens lacking an IR (infrared) cut filter inserted in an optical system is used.

On the front side of the third frame 9, a cylindrical light emitting element 5 which emits an infrared spot light of about 3 mm and reflected infrared light from the light emitting element 5 are provided on both sides of the taking lens 3. A cylindrical light receiving element 6 for receiving light is fixed.
The light emitting element 5 and the taking lens 3 (including the image pickup element 4. Hereinafter,
the same. ) And the light receiving element 6 are linearly arranged in the substantially horizontal direction and in the same direction. The light emitting element 5 and the light receiving element 6 form an active distance measuring unit, and the distance measuring range of the distance measuring unit is within about 5 m.

From the outer peripheral side surfaces of the light emitting element 5 and the light receiving element 6 to the opposite side of the image pickup element 4, respectively, in a substantially horizontal direction,
A tilt direction support shaft 11 is provided to project so as to support the third frame so as to be rotatable in the tilt direction (vertical direction) with respect to the second frame. These tilt direction support shafts 11 are coaxial and are supported by the second frame. The protruding position of the tilt direction support shaft 11 of the light emitting element 5 and the light receiving element 6 is the position closest to the second frame in the vertical direction, and the center of gravity position in the vertical direction with respect to all the members fixed to the third frame. (When viewed from the front side, the light emitting element 5 and the light receiving element 6 are equally divided into upper and lower diametrical positions) and
The position is the position of the center of gravity in the depth direction with respect to all the members fixed to the third frame.

A plate material having substantially the same thickness as that of the third frame 9 is provided so as to project in the rear direction of the camera section main body from a position slightly closer to the light emitting element 5 from the center on the back surface side of the third frame 9. An elongated hole is formed in the central portion of this plate material. On the back side of the third frame 9, a CCD operation control circuit for controlling the operation of the image sensor 4 and a control circuit board for controlling the camera body (see reference numeral 20 in FIG. 4) are mounted as described later. Has been done. A lead wire is led out from the control board, and is connected to a connector portion (not shown) arranged on the back side of the casing 2a to secure the connection with the host portion.

From one side of the second frame 8 (light emitting element 5 side), a motor fixing plate having a substantially V-shaped cross section extends in the rear direction. The third frame 9 is attached to the tip of the motor fixing plate.
A stepping motor (hereinafter referred to as “tilt motor”) 12 for tilt-moving the actuator in a substantially vertical direction has two cylindrical fixed arms 12 extending from the tilt motor 12.
It is fixed by screwing through b. Tilt motor 12
A substantially L-shaped drive lever 12a is fitted to the motor shaft of the. The tip portion of the drive lever 12a has the above-mentioned third portion.
It is inserted into the long hole of the plate material of the frame 9.

On the other hand, on the back surface side (bottom surface side) of the central portion of the first frame 7, a stepping motor (hereinafter referred to as a pan motor) 13 for pan-driving the second frame 9 in a substantially horizontal direction is provided. It is fixed by screws via two cylindrical fixing arms (not shown) extending from the. A substantially L-shaped drive lever 13 a is fitted on the motor shaft of the pan motor 13. Drive lever 13
The tip portion of a is U formed at the position of the second frame 9 corresponding to the substantially midpoint position between the taking lens 3 and the light receiving element 6.
It is inserted in the letter notch.

Therefore, the third frame 9 is pivotally supported by the tilt direction support shaft 11 so as to be rotatable in the tilt direction with respect to the second frame 8, and the second frame 8 is supported by the pan direction support shaft 10 on the first frame 7. Since it is rotatably supported by the shaft,
The light emitting element 5 and the taking lens 3 fixed to the third frame 9.
Also, the light receiving element 6 includes a pan motor 13 and a tilt motor 1.
It is structured such that the direction (direction) can be integrally changed in the horizontal and vertical directions by the drive of 2. It should be noted that the tilt motor 12 and the pan motor 13 are provided with driving levers 12a and 13a for half a turn (1) instead of the stepping motor in this example.
A meter with a rotation position sensor that rotates less than 80 ° may be used.

As shown in FIG. 4, the camera body has a control circuit 20 for controlling the drive of the tilt motor 12 and the pan motor 13, and the emission and reception of infrared rays from the light emitting element 5, the light receiving element 6 and the light emitting LED 14. is doing. The control circuit 20 has a microcomputer (hereinafter referred to as a microcomputer) 21 having a CPU, a RAM, a ROM and an interface built therein, a driver 25 for causing the light emitting element 5 to emit light in response to an H (high) level signal from the microcomputer 21, and an arithmetic circuit. Then, the infrared LED 1 is generated by the H (high) level signal from the distance measuring device 22 and the microcomputer 21 for photoelectrically converting the infrared reflected light received by the light receiving element 6 to measure the distance to the subject.
Driver 26 for causing 4 to emit light, and tilt motor 1
2. It is configured to include drivers 28 and 29 that drive the pan motor 13 in both forward and reverse directions. The microcomputer 21 is connected to the distance measuring device 22, and the distance measuring device 22
Is connected to the light receiving element 6. The microcomputer 21 is connected to the drivers 25 and 26, and the driver 25,
26 are connected to the light emitting element 5 and the light emitting LED 14, respectively. Further, the microcomputer 21 is connected to the drivers 28 and 29, the driver 28 is connected to the pan motor 13, and the driver 29 is connected to the tilt motor 12. The microcomputer 21 is also connected to the pressure switch 31 described above.

(Operation) Next, the operation of the camera 1 of this embodiment will be described with reference to the flow chart. It should be noted that the microcomputer 21 has completed the initial processing of expanding the programs stored in the ROM and the data such as the setting values described later to the RAM, and makes the image sensor 4 of the camera body face the face of the person P. It is assumed that a framing routine for framing and imaging is ready to be executed.

As shown in FIG. 5, in this framing routine, first, at step 102, the pressure switch 31 waits until it is turned on. Pressure switch 31
Is turned on, in the next step 104, the pan motor 13 and the tilt motor 1 are sent to the drivers 28 and 29.
2 is driven to move the camera body (distance measuring unit) so as to face the initial position in the distance measuring direction, and the driving of the pan motor 13 and the tilt motor 12 is stopped.

As shown in FIG. 6, the distance measuring direction D of the distance measuring unit is restricted within the distance measuring allowable range S in the pan direction (horizontal direction) and the tilt direction (vertical direction). The distance measurement allowable range S depends on the movable range of the pan motor 13 and the tilt motor 12. It should be noted that the distance measurement allowable range S shown in FIG.
[Fig. 3] schematically shows the distance measuring range of the distance measuring unit at the position of the person P. Initial position (initial direction) S
_O is the position of the lower end in the tilt direction and the one end in the pan direction of this allowable range S. The lower end of the allowable range S in the tilt direction is set to a position above the floor surface at the limit of the distance measurement range of the distance measurement unit, in other words, the distance measurement range is shorter than the distance to the floor surface. ing. The initial position S _O is set at a position where the person P (or the person P ′) does not exist in the horizontal direction within the distance measurement allowable range S, and the person P (or the person P ′) exists in the vertical direction. Is set to the position (see also FIG. 1).

In the next step 106, an H level signal is output to the driver 25 to turn on the light emitting element 5. As a result, the light-receiving element 6 is ready to receive the infrared reflected light reflected by the person P (or person P ′).

In the next step 108, the driver 28 drives the pan motor 13 to move the distance measuring direction D in the pan direction (direction of arrow A in FIG. 6). As a result, the distance measuring direction D moves from the initial position S _O to the pan direction end position S _E in the pan direction while keeping the tilt direction at the initial position. The end position S _{E in the} pan direction is the authentication area 3
It is set at a position where the person P does not exist on the opposite side of the initial position S _O with 4 in between.

Next, at step 110, the light receiving element 6
It is determined whether or not there is a change in the signal received in step S1, in other words, whether one side P _A or the other end P _B of the person P has been captured. The distance measuring device 22 measures the distance to the subject by the voltage from the light receiving element, and as shown in FIG. 6, the person P has one side P _A , the other end P _{B of the} person P _{, and the} person P more than _the person P. The microcomputer 21 outputs the distance measurement information (distance information) in each distance measurement direction D during the pan operation including the end portion (not shown) of the person P ′ located at a distance.
Is output to. Therefore, the microcomputer 21 positions captured the subject, i.e., it is possible to determine the one side P _A and the other end P _B of the person P.

If the determination in step 110 is negative,
The process proceeds to step 114, and if the result is affirmative, the next step 1
In FIG. 12, the value of the number of pulses output by the driver 28 to the pan motor 13 from the initial position S _O to the position where there is a signal change (one end P _A or the other end P _{B of the} person P) and the measurement from the distance measuring device 22 there. Distance information is stored in RAM.

Next, at step 114, it is determined whether or not the distance measuring direction D has reached the pan direction end position S _E.
Determines whether or not the number of pulses output to the pan motor 13 reaches a predetermined number of pulses. If the determination is negative, the process returns to step 108 to continue the pan driving of the pan motor 13, and if the determination is positive, the driving of the pan motor 13 is stopped in the next step 116. Next, at step 118, the distance information stored at step 112 is read and the subject (person P) closest to the camera 1 is selected.

In the next step 120, step 112
One side P of person P stored in_AAnd the other side P_BPulse up to
The value of the number is read, and the value of the number of pulses in the middle {(P_AWell
Number of pulses at + P_BPulse number up to) / 2}
And the position (direction) of the calculated pulse number is used as the body axis of the person P.
Position (body axis direction) P_CAnd Initial position S_OFrom bread
Directional end position S_EDriver 28 goes out to pan motor 13
The number of applied pulses is constant and the initial position S_OFrom the axial position
Setting P_CSince the number of pulses up to is calculated,
By subtracting the latter, the distance measuring direction D of the distance measuring unit is
End position S _ETo body axis position P_CTo turn to
The number of pulses can be calculated. In step 122
Is the pan motor 13 for the number of pulses calculated in this way.
To drive in the reverse direction to move the distance measurement direction D to the body axis position P_CTowards
The driving of the pan motor 13 is stopped.

Therefore, the distance measuring unit has a distance measuring allowable range S.
The lower end horizontal, the normal rotation of the pan motor 13, a person from the initial position S _O P, the direction to pan direction end position S _E through the P ', after stopping once in the pan direction end position S _E, By driving the pan motor 13 in the reverse direction, the body axis position P _C is turned.

In step 124, the driver 29 drives the tilt motor 12 so that the distance measuring unit faces upward (in the direction of arrow B in FIG. 6) from the body axis position P _C , and in the next step 126, there is a signal change. Determine whether or not.
That is, as shown in FIG. 6, when the distance measuring unit is turned upward from the body axis position P _C , a signal change is obtained at the head end (top of the head) P _D of the person P. Based on this signal change, it is determined whether the distance measuring direction D has exceeded the head end P _D.

When a negative determination is made in step 126, in step 128, the permissible distance measurement range S at the body axis position P _C.
End position S in the body axis tilt direction, which is the inner end (upper end position)
_It is determined whether or not the drive has been performed up to _C, and if the determination in step 128 is negative, the process returns to step 124 to make the distance measuring direction D further upward. The upper limit position of the distance measurement allowable range S can be set in consideration of the fact that there is no person whose height exceeds approximately 2.5 m and the installation position of the camera 1 in the vertical (height) direction. If the determination in step 128 is affirmative, it is considered that the person P has moved, so
In the next step 130, it is determined whether the pressure switch 31 is in the on state. When the determination in step 130 is affirmative, it is assumed that the person P exists in the authentication area 34, but since the person P has moved, the framing of the face of the person P cannot be accurately obtained even if the framing routine is continued as it is. Then, the process returns to step 104 again, and when the negative determination is made in step 130, the person P does not exist in the authentication area 34, so the framing routine is ended.

On the other hand, when the determination in step 126 is positive, since the distance measurement direction D exceeds the head end P _D of the person P, in step 132, it stops the tilt operation of the tilt motor 12, the light emitting element Turn off 5 Next, in step 134, the tilt motor 12 is reversely driven, and in the next step 136, it is determined whether or not the driver 29 has output a predetermined pulse number set in advance to the tilt motor 12. When framing a human face like the camera 1 of the present embodiment, the head end P above the body axis position P _{C
When D} is known, the size of a person's face is generally determined, and therefore, a position below, for example, about 15 cm from the head end P _D can be considered as the center P _E of the face of the person P. In step 136, the distance measuring direction D is the center P _E of the face of the person P.
In order to determine whether or not the tilt motor 12 has been output to the tilt motor 12, it is determined whether or not a predetermined pulse number corresponding to about 15 cm is output to the tilt motor 12.

If a negative determination is made in step 136, step 13 is executed to continue the reverse rotation drive of the tilt motor 12.
Returning to step 4, when the determination is affirmative, the reverse rotation drive of the tilt motor 12 is stopped in step 138.

Therefore, the distance measuring unit has the distance measuring allowable range S.
From the body axis position P _C of the lower end of the
By the forward rotation drive of No. 2, the head P passes through the head P _D of the person P and then stops, and then the tilt motor 12 is driven in the reverse direction to face the center P _E of the face of the person P. The image sensor 4 is
Since the distance measuring unit is arranged on the third frame 9 so as to be linear and substantially horizontal in the same direction as the distance measuring unit, the distance measuring unit faces the center P _E of the face of the person P. 6
As shown in, the face of the person P is framed at an angle of view V _A centered on the center P _E of the face of the person P.

Next, in step 140, the light emitting LED 14
Is turned on, and in the next step 142, a framing completion signal for notifying the host unit of the completion of framing is output, and the framing routine is ended. As a result, the host unit captures the image from the image sensor 4, performs the image processing for extracting the data such as the facial feature amount of the person P, as described above, and stores the image of the person P stored in the database of the host unit. The door 33 is unlocked when it coincides with the characteristic amount.

(Operation etc.) Next, the operation etc. of the camera 1 of this embodiment will be explained.

In the camera 1 of this embodiment, the pan motor 1
3 performs pan operation at the lower end of the tilt direction (step
104-116), ranging unit capable of unidirectional ranging
From the signal change by the (light emitting element 5 and the light receiving element 6), the person P
Body axis position P_CIs found (steps 118, 12)
0). Next, the tilt motor 12 is used to move the body axis position P.
_CFrom the (lower end in the tilt direction), the tilt operation is upward
From the signal change made by the distance measuring unit, the head end of the person P
P_DAre searched for (steps 124 to 132). That
The face of the person P found by the tilt motor 12
Center P_EWhen the shooting direction D of the shooting lens 3 is directed to the person
Center P of face of object P_EIs the angle of view V_AFramed by
(Steps 134 to 138), the face of the person P using the image sensor 4
Will be taken. Therefore, the camera 1 of the present embodiment is
(1) Initial position S_OTo end position S in pan direction _EUp to positive
Panning operation, (2) Pan direction end position S_ETo axial position
P_BReverse pan up to (3) Body axis position P_BFrom head
Edge P_DForward tilt motion up to (4) Head end P_D
To the center P of the face of person P_EReverse tilt operation up to 4 of
You can frame the face of person P by the action
Thus, the image of the face of the person P can be quickly obtained. Obey
Therefore, according to the camera 1 of the present embodiment, the person P in the stationary state is
Since you can quickly get the image of the face of
Cuts the face portion of the person P from the background or the like as in the prior art.
Shortened image processing time because no trimming process is required
It is possible to reduce the size of the
The number of pixels is small because it is not necessary to increase the resolution of the image sensor 4
Not a low cost camera can be used. In other words
Then, by using the camera 1 of the present embodiment,
After capturing the image, the trimming process centering on the face of the person P
After the trimming process at the time of capturing the image without the need for reason
Since the image can be obtained, the processing time of the host unit
Shortening and cost reduction of the camera can be achieved.

Further, in the present embodiment, when the forward pan operation from the initial position S _O to the pan direction end position S _E is performed, the distance measurement unit of the distance measurement unit is set shorter than the distance to the floor surface. Since it is within about 5 m, the distance measuring unit can framing the face of the person P without erroneously recognizing the floor surface as a subject.

In most cases, the subject (person P) to be photographed exists at the position closest to the camera 1. Therefore, in this embodiment, when there are a plurality of subjects including persons P and P '. However, by identifying the face of the person P, which is the subject closest to the camera 1, with the image sensor 4, the identification of the subject is simplified. Therefore, in this embodiment, the microcomputer 2
Although the example in which 1 is operated by software (program) is shown, the control circuit can be configured by hardware including a comparator (comparator) or the like regardless of the microcomputer 21 or software, so that the cost is lower. And downsizing can be achieved.

Further, the camera 1 of the present embodiment employs active type triangulation. Therefore, by causing the light emitting element 5 to emit light in the infrared region, a subject such as the person P can be searched for even in a dark place. In addition, the camera 1 of the present embodiment once searches for the center of the face of the person P, and then causes the infrared LED 14 to emit light (step 140),
Since the image of the face of the person P is taken by the image sensor 4, the person P as a subject is not surprised or the eyesight of the person P is not damaged.
Furthermore, in the camera 1 according to the present embodiment, since the taking lens 3 does not include the IR cut filter, the image sensor 4
Can be photographed in the infrared region. That is, since the authentication camera 1 as in the present embodiment is generally arranged in a relatively dark place such as a corridor or a hallway, an infrared active system is adopted, and the infrared LED 14 projects light onto a subject. ,
By using the taking lens 3 from which the IR cut filter is removed, the original function of the authentication camera capable of taking a picture even in a dark place can be exhibited.

Furthermore, in the camera 1 of this embodiment, the light emitting element 5 having a light spot diameter of about 3 mm is used. If the light spot diameter is too large, the output from the light receiving element 6 may be difficult to determine, and the contour of the person P or the like may be blurred. In the camera 1 of the present embodiment, since the light spot of the light emitting element 5 has a small diameter that does not cause blurring, it is possible to accurately grasp the signal change and to frame the face of the person P without error. .

In the present embodiment, an example in which a person's face is framed and photographed has been shown, but the present invention is not limited to this, and a camera for framing and photographing a specific part of an object can be used. It can be applied without question. In such a case, the positions corresponding to one side, the other side, and the head end may be determined according to the shape of the object to be imaged.

Further, in this embodiment, the continuous light emitting type LED 14 is exemplified, but a flash type light emitting LED may be used. In this way, a clear image of the face of the person P can be obtained even if the camera 1 is placed in a pitch dark place.

Further, in the present embodiment, the application example in the dark place excluding the IR cut filter from the taking lens 3 is shown, but when the camera 1 is always arranged in the bright place,
By inserting an IR cut filter into the taking lens 3,
An unnecessary infrared ray may be excluded from the rays entering the image pickup device 4 to obtain an image that is familiar to the human eye.

Further, in the present embodiment, an example in which the control circuit 20 is provided on the camera 1 side is shown, but such a control circuit 2 is provided.
0 can perform the same function by software on the outside of the camera 1 or on the host unit side (not shown) described above. In such a mode, a control interface for connecting the host unit side and the camera side is secured, or the BLUE
A wireless link represented by TOOTH should be secured.

In the present embodiment, in order to direct the angle of view _VA of the camera 1 to the face of the person P, the tilt motor 12 is tilt-driven from the body axis position P _{C in the} direction of arrow B in FIG. 6 (upward). Although the example is shown, the body axis position P within the allowable range S
_{From the} body axis tilt direction end position S _C , which is the upper end of _C, to the arrow B
The tilt motor 12 may be tilt-driven to the side opposite to the direction (downward) to capture the signal change at the head end P _D.

(Second Embodiment) Next, a second embodiment in which the present invention is applied to an automatic framing camera for automatically framing a human face will be described. In the present embodiment, the same members and steps as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.
Only different parts will be explained.

As shown in FIG. 7, in the present embodiment, the light emitting element 5, the taking lens 3 and the light receiving element 6 are linearly arranged in a substantially horizontal direction.
_D is set so as to be lowered by a predetermined angle θ from the distance measuring direction D of the distance measuring unit. This angle θ is CC of the image sensor 4.
When the distance from the D surface to the person P is L1 and the distance from the face center P _E of the person P to the head end P _D of the person P is L2 (for example, 15 cm), tan θ = L2 / L1 Given. As shown in FIG. 1, the authentication area 34
By reducing (particularly, the side in the direction toward the camera 1), the accuracy of this angle θ is increased, and the framing accuracy of the face of the person P can be increased.

As shown in FIG. 8, the camera 1 according to the present embodiment.
In the framing routine of step 1 shown in FIG.
32 to step 136 is missing. That is, in this embodiment, as shown in FIGS. 7 and 9, the range finding directions D of the photographing direction C _D is the distance measuring unit of the taking lens 3, the person P
L2 from the center P _E of the face of the person to the head end P _D of the person P
Since the corresponding lowered by an angle θ is set to, when the signal change is obtained by the head end P _D of the person P, when stopping the driving of the tilt motor 12, the imaging element at that position (direction) In FIG. 4, the center P _E of the face of the person P can be captured as the center of the angle of view V _A.

According to the camera of the present embodiment, the steps 132 to 136 are not required to capture the face of the person P, that is, the description will be given in accordance with the first embodiment. (4) Since there is no reverse tilt operation from the head end P _D to the center P _E of the face of the person P, the face of the person can be framed more quickly than the camera 1 of the first embodiment.

[0055]

As described above, according to the first aspect of the present invention, the top of the head of the person is searched for next to the body axis of the person from the change of the distance information by the distance measuring means, and the top of the head is searched. By lowering the shooting direction by a predetermined angle from, the substantially center of the face of the person is framed, so that the face of the person can be quickly framed. According to the second aspect of the present invention,
Since the photographing direction of the photographing means is set lower than the distance measuring direction of the distance measuring means by a predetermined angle, the photographing direction is a predetermined angle from the top of the head found by the direction changing means as in the first aspect. It is not necessary to lower the frame to frame the substantially central portion of the person's face on the photographing means, and it is possible to obtain the effect that the person's face can be framed more quickly than in the first mode.

[Brief description of drawings]

FIG. 1 is an external perspective view schematically showing an arrangement position of an automatic framing camera of a first embodiment to which the present invention can be applied.

FIG. 2 is an external perspective view of the automatic framing camera of the first embodiment.

FIG. 3 is an external perspective view showing a schematic configuration of a camera body of the automatic framing camera of the first embodiment.

FIG. 4 is a block diagram showing a schematic configuration of a control circuit of the automatic framing camera of the first embodiment.

FIG. 5 is a flowchart of a framing routine executed by a microcomputer of a control circuit of the automatic framing camera of the first embodiment.

FIG. 6 is an explanatory diagram schematically showing a distance measuring direction and a distance measuring allowable range of the automatic framing camera of the first embodiment.

FIG. 7 is an explanatory diagram schematically showing the angular relationship between the taking lens and the distance measuring unit of the automatic framing camera of the second embodiment to which the present invention is applicable.

FIG. 8 is a flowchart of a framing routine executed by a microcomputer of a control circuit of the automatic framing camera of the second embodiment.

FIG. 9 is an explanatory diagram schematically showing a distance measuring direction, a photographing direction, and a distance measuring allowable range of the automatic framing camera of the second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Automatic framing camera 3 Photographing lens (part of photographing means) 4 Imaging element (part of photographing means) 5 Light emitting element (part of distance measuring means) 6 Light receiving element (part of distance measuring means) 12 Tilt motor ( Part of direction changing means) 13 Pan motor (part of direction changing means) 20 Control circuit (part of distance measuring means, part of direction changing means) 22 Distance measuring device (part of distance measuring means)

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) G03B 15/00 H04N 5/225 C G02B 7/11 Z H04N 5/225 G03B 3/00 A

Claims (4)

[Claims] 1. A change for integrally changing a photographing means for photographing a subject, a distance measuring means for measuring a distance in one direction, and a photographing direction of the photographing means and a distance measuring direction of the distance measuring means. In the automatic framing camera including means for framing and photographing a person's face, a panning operation is performed at the lower end of the tilt direction by the direction changing means, and the body axis of the person is searched for from the change in the distance information by the distance measuring means, The direction changing means performs a tilting operation from the lower end or the upper end in the tilt direction of the body axis to find the top of the person's head from the change in the distance information by the distance measuring means, and the direction changing means to find the top of the head. The automatic framing device is characterized in that the approximate center of the face of the person is framed by the photographing means by lowering the photographing direction by a preset angle from Camera. 2. A change for integrally changing a photographing means for photographing a subject, a distance measuring means for measuring a distance in one direction, and a photographing direction of the photographing means and a distance measuring direction of the distance measuring means. In the automatic framing camera that includes means for framing and photographing a person's face, a panning operation is performed at the lower end of the tilt direction by the direction changing means, and the body axis of the person is searched for from the change in the distance information by the distance measuring means. The tilting operation is performed from the lower end or the upper end in the tilt direction of the body axis by the direction changing means, the top of the head of the person is searched from the change in the distance information by the distance measuring means, and the photographing direction of the photographing means is the distance measuring means. Is set to be lower by a predetermined angle with respect to the distance measuring direction, the approximate center of the person's face is framed by the photographing means when the top of the person's head is searched. An automatic framing camera that is characterized by 3. The direction changeable range of the direction changing means is set in advance, and when the direction changing means performs a pan drive at the lower end of the tilt direction, the distance-measurable distance of the distance measuring means reaches the floor surface. The distance is less than the distance of.
Alternatively, the automatic framing camera according to claim 2. 4. The predetermined angle is tan ⁻¹ when the distance between the photographing means and the person is L1 and the distance from the approximate center of the person's face to the top of the person's head is L2.
3. It is given by (L2 / L1).
Automatic framing camera described in.