JPH06217304A - Three-dimensional coordinate automatic measurement system in voice tracking automatic sighting system - Google Patents

Abstract

PURPOSE:To avoid direct operation by the operator or a participant and to allow the system to flexibly cope with number of participants and installed location or the like with respect to the 3-dimension coordinate automatic measurement system in the voice tracking automatic sighting system in which coordinate data of a seat position of an utterance party corresponding to the detection of a voice signal are used to calculate an utterance party and a distance of a camera thereby controlling the camera. CONSTITUTION:A transmitter 2 used to transmitting a specific radio signal is fitted respectively to a microphone 1 provided corresponding to each seated position of a conference participant, a camera 4 is fitted to a fixed position in front of entire seats and at least three 2-dimensional receivers 3A-3C are arranged on a face in the vertical direction opposite to the seats at three positions fixed to the camera 4 respectively. A reception angle of a reception sinal is measured by a reception angle measurement sections 5A-5C by controlling each receiver and the coordinate of the transmitter is obtained by calculation through the use of the measured reception signal, the reception angle and the coordinate of the receiver to obtain the coordinate of each participant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional coordinate automatic measuring method in a voice tracking type automatic aiming method of a video conference system.

In recent years, a video conference system for connecting remote locations has come into wide use. Some of these video conference systems are capable of automatically capturing the speaker during the conference and focusing the TV camera on the speaker. However, in order to capture the speaker and immediately point the television camera at that person,
It is necessary to preset the coordinate position of the person.

[0003]

2. Description of the Related Art The same applicant as the applicant of the present invention has previously referred to a video conference system by the name of the invention "Voice Tracking Automatic Aiming Method" (Japanese Patent Application No. 4-243865, Sep. 1992).
(Application on the 14th of a month).

In the video conference system using a moving image or a still image between remote places, the method detects a voice uttered by a speaker, detects the speaker, moves a camera device in the direction of the speaker, It automatically focuses on a natural image regardless of the number of speakers.

FIG. 6 is a block diagram of the proposed system. In the figure, reference numeral 90 denotes a central control unit, in which the video control unit 9
Reference numeral 00 denotes a video reception unit 900a that controls the reception of video, an aiming control unit 900b that controls the aiming of the camera, and a focus calculation unit 900 that calculates the focus of the camera based on the position of the speaker.
An attitude control unit 90 for controlling the attitude (direction) of the camera c and the camera.
With 0d. The voice control unit 901 includes a voice receiving unit 901a that controls reception of voice, and a source detection unit 901b that detects a source from a signal output of a microphone. 902
Is an input / output control unit.

Reference numeral 91 denotes a main storage device, and a seat information unit 910 therein has a basic information unit 910a storing basic information such as the coordinates of a reference microphone, and each position of each seat to the table 96 is tertiary. It is composed of an individual information section 910b that stores information expressed in original coordinates and a focus recording section 910c that stores information such as the direction of the camera and the focus position.

Reference numeral 92 denotes a camera drive unit, 93 denotes a camera, 9
4 is a monitor for displaying the image of the camera 93 in this place and the image received from the remote video conference system, 95 is a speaker for outputting the voice of the speaker, 96 is a table in the conference room, and ~ are fixed positions. The seat is a M1
M9 are microphones arranged on the table. Reference numeral 97 is an information communication network, and 98 is a remote video conference system.

With the space in the conference room as a three-dimensional coordinate, the positions of the seat to the table 96 are represented by relative coordinates starting from the camera 93 and recorded in advance in the seat information section 910 in the main memory 91. I'll do it. When there is a speaker in the conference, the utterance is detected by the microphone, the voice controller 901 detects the speaker information, and the information is passed to the video controller 900. Based on the passed information, the image control unit 900 can identify the speaker by the focus operation unit 900c and perform an operation according to an algorithm for obtaining the coordinates of the focus to calculate the focus coordinates that optimize the image. The calculation result is the aiming control unit 900b and the attitude control unit 900.
Passed to d. The aiming control unit 900b sends control information to the automatic aiming device incorporated in the camera 93 to focus the target according to the calculation result. The attitude control unit 900d derives a relative vertical and horizontal angle from the calculation result to the focus when the direction of the camera 93 is set to an angle of 0, and causes the drive unit 92 to change the direction so that the focus is located at the center of the image.

As a result, the image obtained by the camera 93 is received by the image receiving unit 900a, the voice is received by the audio receiving unit 901a, the audio signal and the image signal are combined by the input / output control unit 902, and the information communication is performed. It is sent to the remote video conference system 98 via the network 97. The signal transmitted from the remote video conference system is input / output control unit 902.
Are received, separated into audio signals and video signals, and output to the speaker 95 and the monitor 94, respectively.

[0010]

In the proposed voice tracking type automatic aiming system shown in FIG. 6, the seat information is obtained in order to obtain the information of the photographing position, the angle of view and the focus corresponding to the position of the attendee. It is necessary to set the position information represented by the three-dimensional coordinates (based on the camera 93) of each attendee in the section 910. For this position information, there is a method of setting the position information of the attendees immediately before the meeting, or determining the seat position of the attendees in advance, and setting a predetermined value for each position information. . However, these methods have the following problems.

In the method of [1], the attendant is seated,
A dedicated operator or one of the attendees must operate the camera to set the shooting position, angle of view, and focus. If the seating position or camera position changes for each meeting, the shooting position, There is a problem that the angle of view and focus must be set.

In the method of (1), since the position of the seat is determined in advance and the position information is set, it is necessary to fixedly determine the position of the camera, the position of the seat, the installation location of the device, etc. There is a problem of being limited.

The present invention, in the audio tracking type automatic aiming system of the video conference system, the coordinate information of the attendees necessary for automatically controlling the photographing position (determined by the position of the speaker), the angle of view, and the focus. It is an object of the present invention to provide an automatic three-dimensional coordinate measurement method capable of flexibly responding to the number of attendees, the installation location, etc. without directly setting the settings by an operator or attendees.

[0014]

FIG. 1 is a block diagram showing the principle of the present invention. In FIG. 1, reference numeral 1 denotes a microphone provided at an arbitrary position on the table, and a plurality of microphones are provided. Two
Is a transmitter attached to each microphone 1, and 3A to 3C are first to third receivers each having a two-dimensional antenna. The first and second receivers are horizontal, and the third receiver is Are scanned vertically. 4 is a TV camera, 5A
5C is a first reception angle measurement unit to a third reception angle measurement unit that identifies the angle of a signal received by each receiver, 6 is a penetration angle corresponding to each receiver, a signal control unit that handles the received signal,
Reference numeral 7 is an information control unit that performs calculation for identifying a signal and obtaining coordinates of a transmission source (transmitter), and 8 is a main storage unit that stores various information including coordinates of each transmission source.

According to the present invention, a transmitter is provided in a microphone provided at an arbitrary position, a signal transmitted from the transmitter is received by a plurality of receivers whose coordinates are predetermined, and the reception angle at each receiver is determined. Sources (microphones) identified and based on each reception angle
The coordinate of is obtained and stored.

[0016]

In FIG. 1, each microphone 1 provided on the table has a transmitter 2 for transmitting its own radio signal.
Is attached. The signal to be transmitted includes a unique code corresponding to the microphone when it is composed of a digital signal, and is composed of a unique frequency or amplitude when it is an analog signal. The first to third receivers 3A to 3C that receive the signal generated from the transmitter 2 of the microphone 1 are arranged at the positions corresponding to the respective corners of the triangle. In this case, the position of the camera 4 is used as a starting point (origin of the three-dimensional coordinates), the front and rear directions thereof are the Y axis, the left and right directions are the X axis, and the vertical direction is the Z axis as shown in FIG.
As an axis, the first and second receivers 3A and 3B are arranged on the X-axis, and the third receiver 3C is arranged on the Z-axis.
The positions of 3C are represented by coordinates relative to the camera, and are stored in the main storage unit 8 in advance.

When the signal transmitted from the transmitter 2 attached to the microphone 1 is received by each of the receivers 3A to 3C, the reception angle measuring units 5A to 5C measure the reception angles. The signal control unit 6 collects the received signal, the reception angle, and the information of the receiver, and passes them to the information control unit 7. The information control unit 7 stores the received reception angles in the main storage unit 8 and
The calculation is performed based on the information stored in (1) to obtain the coordinates of each transmission source (microphone), and the calculation result is stored in the main storage unit 8.

[0018]

FIG. 2 is a block diagram of an embodiment. In FIG. 2, 1 to 6 correspond to components or circuits having the same reference numerals as those shown in FIG. 1, 1 is a microphone, 2 is a transmitter attached to each microphone 1, and 2A to 3C are receivers. , 4 is a camera, 5A to 5C are reception angle measuring units, and 6 is a signal control unit.

Further, 9 is a conference table, 17 is a central control unit, in which an information control unit 7 (corresponding to 7 in FIG. 1) is provided.
18 is a main storage device (corresponding to the main storage unit 8 in FIG. 1)
Is.

In this embodiment, the configuration for three-dimensional coordinate measurement according to the present invention is mainly shown, and a configuration for executing automatic aiming by voice tracking (see FIG. 6) is also provided, but it is shown in the drawing. Omitted.

The microphone 1 may be of a type placed on the conference table 9, but it may be placed on the conference table 9 by using a small one that can be carried by the participants of the video conference. The transmitter 2 attached to the microphone 1 emits a unique signal so that a plurality of microphones can be identified as described with reference to FIG. Further, the positions of the receivers 3A to 3C are fixedly arranged with respect to the camera 4,
Is placed in the middle of the line connecting the receivers 3A and 3B, the position of the camera 4 is changed to the reference coordinate (x) of the three-dimensional coordinates (x, y, z).
₀ , y ₀ , z ₀ ), the three-dimensional coordinates of each of the receivers 3A to 3C with respect to this reference coordinate are shown as A, B, and C in the basic information section 80 of the main memory 18 as shown in FIG. It is stored.

The X axis is the receiver 3A, the cameras 4 and 3
The line connecting B, the Y axis corresponds to the center line from the camera 4 to the seat, and the Z axis corresponds to the line connecting the position of the camera 4 to the receiver 3C.

First, the conference participants sit at appropriate positions (not fixed) on the table, each adjusts the position of the microphone 1 (when the position is variable), and turns on the power. As a result, the transmitter 2 attached to the microphone 1 starts the transmission operation. At this time, it is not necessary to allocate one microphone 1 and one transmitter 2 to each attendee (it is also possible to have one for two people). The signal transmitted by this is the receiver 3A, respectively.
.. to 3C, the reception angle measuring unit 5C connected to the receivers 3A to 3C measures the angles at which the signals from the receivers 3A to 3C enter.

The structure of the reception angle measuring unit and the operation of the receiver will be described with reference to FIGS. 3 and 4. FIG. 3 is a configuration of the reception angle measuring unit, and FIG. 4 is a diagram showing directions in which each receiver rotates.

Referring to FIG. 1 shows one receiver and a reception angle measuring unit and a signal control unit connected to this, and B. Shows the relationship with the signal when the receiver is viewed from above. A. of FIG. As described above, each receiver has a configuration in which the support having the two-dimensional receiving directional antennas 3-1 and 3-2 at both ends is rotated by the rotating motor 30. B. of FIG. 3 when this antenna is viewed from above. The direction of arrival of the signal is detected by receiving the signal with the directional antenna while rotating the antennas 3-1 and 3-2 with respect to the signal input from the transmitter (2 in FIG. 2) as shown in FIG. You can

Such a receiver and a reception angle measuring unit are provided at two locations in the horizontal direction (3A and 3B in FIG. 2) and one location in the vertical direction (3C in FIG. 2), and measurement is performed by the three receivers. As a result, the signal source can be measured as one point in the three-dimensional space. In that case, the receivers 3A and 3B detect the angle in the horizontal direction as shown in FIG.
The antenna is rotated about the Z-axis as a rotation axis on a two-dimensional plane including the X-axis and the Y-axis of the three-dimensional coordinates, and the receiver 3C receives the two axes including the Z-axis and the Y-axis as shown in FIG. Scanning is performed in the vertical direction by rotating up and down with the X axis as the axis of rotation on the dimensional plane.

Referring to FIG. As shown in FIG.
Is composed of a motor controller 50, a measurement timer 51, a signal receiver 52, and a reception angle calculator 53. First, the motor control unit 50 controls the rotation motor 30, and the measurement timer 51 is reset every one rotation or every half rotation. For example, if the receiving angle measuring unit 5 controls the receiver (antenna) to make one rotation in 360 seconds, one antenna can be rotated by half a turn to scan at least 180 degrees forward, and the objective can be achieved. Done in seconds.

At this time, the signals received by the receiving antennas 3-1 and 3-2 are received by the signal receiving section 52, the timing (corresponding to the angle) received from the measuring timer 51 is extracted, and the reception angle calculating section 53 is obtained. Hand over to. The reception angle calculation unit 53 analyzes the pattern of the signal (identification information of the reception signal (identification information of the transmitter)), measures the reception (penetration) angle of the signal from the reception timing, and measures the analyzed signal pattern. The penetration angle is output to the signal controller 6.

Returning to FIG. 2, the signal control unit 6 receives information (identification information of reception signal, reception angle) passed from the reception angle measuring units 5A to 5C corresponding to the receivers 3A to 3C, respectively. The data is output separately to the central controller 17. In the central control unit 17, the information control unit 7 is activated by this, the signal received from the signal control unit 6 is identified by the received signal identification unit 70, and the reception angle recording unit of the main storage unit 18 is divided for each receiver. It is stored in 81. On the right side of the reception angle recording unit 81 in FIG. 2, an example of each reception angle measured by the receiver 3A for each transmitter is enlarged and shown. In this example,
Reception angles for a plurality of transmitters represented by a, b, c ... Z are stored.

Subsequently, the coordinate calculation unit 71 of the information control unit 7
Calculates the coordinates of the transmitter by the following method based on the information stored in the reception angle recording unit 81. FIG. 5 is a diagram showing the relationship between the coordinate positions of the various parts used in the coordinate calculation of the transmitter. Indicates the relationship of three-dimensional coordinates, and B. Is A. Shows the position on the X, Y plane for a particular point at.

FIG. 5A. , Point O is a camera (Fig. 2
4) position, which is the origin of three-dimensional coordinates (0,0,0)
And Points A to C are respectively the receivers 3A shown in FIG.
It is the position of 3C, and the direction from each point A to C to the point O is measured as 0 degree.

Assuming that the position of the transmitter to be measured is point P, ∠OAP, ∠OBP and ∠O are set by each receiver.
CP is measured. It is assumed that the point P is in the positive direction with respect to the Y axis.

First, for ΔABP, 180 ° = ∠OAP
Since + ∠OBP + ∠APB, ∠APB = 180 °-(∠OAP + ∠OBP).・ ・ ・ Equation 1 Next, the coordinates of point A and point B are (xa, ya, za), (xb, yb, z
When b), the length of the line segment AB is, AB = √ {(xa- xb) 2 + (ya-yb) 2 + (za-zb) 2} was Equation 2-1, △ ABP About, by the sine theorem,
The following relational expressions 3-1 and 3-2 are established. In addition, ∠OA
Since P, ∠OBP, ∠BAP, and ∠ABP all indicate the corners of ΔABP, ∠OAP = ∠BAP, ∠OBP = ∠A
It is BP.

[0034]

[Equation 1]

From this, the line segment OP is ΔBOP or ΔA.
Since it is one side of OP, according to the cosine (cos) theorem, OP ² = OB ² + BP ² −2 (OB) (OP) cos ∠ OBP OP = √ {OB ² + BP ² −2 (OB) (BP) cos ∠ OBP} Equation 4 Next, regarding ΔCOP, ∠OCP has been measured, and the line segment OC has coordinates (xc, yc, zc) of the point C and coordinates (x ₀ , y ₀ ) of the point O. , Z ₀ ), OC = √ {(x ₀ -xc) ² + (y ₀ -yc) ² + (z ₀ -zc) ² } ... Since the line segment OP is obtained by the equation 4, ∠OPC is obtained by the following equation 5 from the sign theorem.

[0036]

[Equation 2]

Since the following equation 6 is established, ∠COP = 180−∠OPC−∠OCP ... Equation 6 If the Z-axis direction is 0 °, the point P is an angle (180−
(∠COP), it can be said that it is located at the distance OP.

As a result, a straight line intersecting perpendicularly to the Z axis is drawn from the point P, and the intersection is defined as a point D.
Is a right triangle with ∠CDP = 90 °, therefore ∠DOP = 180−∠COP from the above equation 6. Therefore, the line segment OD is expressed by the following equation 7, and the Z-axis coordinate of the point P is
It can be said that it is OD (OPcos∠DOP).

Cos ∠ DOP = OD / OP OD = OP cos ∠ DOP (Equation 7) Next, let us consider a plane composed of an X axis and a Y axis. Z through point P
An intersection of a straight line drawn so as to be parallel to the axis and a plane formed by the X axis and the Y axis is defined as a point P ′. From now on, OD = P
P ′, ∠DOP = ∠OPP ′, and DP =
Since it is OP ', ΔOPD and ΔOPP' are the same. Furthermore, since it is a right triangle, the following equation 8 is established by the Pythagorean theorem.

OD ² + DP ² = OP ² DP ² = OP ² −OD ² DP = √ (OP ² −OD ² ) ... Expression 8 And since DP = OP ′, the following Expression 9 is established. .

OP ′ = √ (OP ² −OD ² ) ... Equation 9 At this time, a straight line obtained by moving the Z axis in parallel to the position of the point A is Z ′, and only the OD from the point A is in the Z axis direction. The point is D '
Then, in □ AD'PP ', the side AD' and the side PP 'are parallel to each other, and AD' = PP ', and ∠AD'P = 90 °. Therefore, □ AD'PP' has two parallel sides. And it can be said that they are equal and one rectangle is a right angle. Therefore, AP '= D'
P.

Since the line segment AP is a diagonal line of □ AD'PP 'and ∠AD'P = 90 °, ΔAD'P is a right triangle and AP is as in the above formula 3-2. A
Since D ′ = OD, the following Expression 10 is established.

Cos ∠PAD ′ = AD ′ / AP ∠PAD ′ = cos ⁻¹ (AD ′ / AP) ∴AP ′ = cos ⁻¹ (OD / AP) ... Equation 10 Further, □ AD′PP ′ is PD 'because it is rectangular
= AP '. As a result, the following Expression 11 is established.

Sin∠PAD ′ = PD ′ / AP PD ′ = APsin∠PAD′∴AP ′ = APsin∠PAD ′ ... Equation 11 B.B. Points A, B, which are represented in the two-dimensional plane of x and y of
Relationship between P ′ and O and known (length of line segment OA), equation 9
From (length of OP ') and expression 11 (length of AP'),
Three sides of AOP 'are introduced. When this is applied to the cos theorem, the following Expression 12 is obtained.

[0045]

[Equation 3]

Here, in FIG. If a straight line perpendicular to the X-axis is drawn from the point P ′ and the intersection point of the straight line and the X-axis is a point A ′, then from the right triangle OP′A ′, cos∠A′OP ′ = OA ′ / OP'OA '= OP'cos∠A'OP' ... Formula 13-1 sin∠A'OP '= P'A' / OP 'P'A' = OP'sin∠A'OP '... Formula 13-2 where OA 'is the length from the point O to the point A'on the X axis, P'A' is the length from the point A'to the point P ', and P'
Since A ′ is parallel to the Y-axis, the x and y coordinates of the point P ′ on the plane consisting of the X-axis and the Y-axis are given by the equation 13-1 and the equation 13-2.
Therefore, it is P '(OA'.P'A').

Therefore, the coordinates (x, y, z) of the point P, which is the transmission source of the signal to be measured, can be calculated using the equation 7, the equation 13-1, and the equation 13
From -2, the following value is required. P (OA'.P'A'.OD) In this way, the operation result obtained by the coordinate operation unit 71 of FIG. 2 is passed to the operation result recording unit 72, and the operation result recording unit 72 is passed. The calculated calculation result is recorded in the coordinate recording section 82 of the main storage device 18. In this way, the coordinate values of all the transmitters 2 (microphones 1) of the conference attendees are recorded in the coordinate recording unit 82. On the right side of the coordinate recording unit 82 in FIG. 2, an example of the contents of the coordinate recording unit 82 is shown in an enlarged manner.
An example in which the coordinate values of a large number of transmitters 2 (microphones 1) represented by b, c ... Z are recorded is shown.

In the above embodiment, the transmission at one location has been described. However, since the signals emitted by the transmitters are different from each other, the same measurement is performed for the simultaneous transmission from a plurality of locations. be able to.

The measurement and recording of the position of the transmitter (the position of the attendees) may be performed only once at the start of the conference, and the attendees are tracked by receiving a signal constantly or at regular intervals. You may allow it.

[0050]

According to the present invention, in the audio tracking type automatic aiming system of a teleconference system between remote places, the position information of the attendees necessary for automatically aiming at the speaker is recorded by the camera. It can be automatically measured as a three-dimensional coordinate relative to.

As a result, it is possible to eliminate the manual work of setting the seat information, which is required when the number of attendees and seat positions are variable in the conventional video conference. In addition, unlike the video conference system in which seat information is preset, it is not necessary to use a special conference room in which the number of people and seat positions are fixed, and there is no restriction on the number of attendees or seat positions, and it is flexible. Since it is possible to respond, it is possible to improve the service to users of the video conference system.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a configuration diagram of a reception angle measuring unit.

FIG. 4 is a diagram showing a direction in which each receiver rotates.

FIG. 5 is a diagram showing a relationship between coordinate positions of respective units used for coordinate calculation of a transmitter.

FIG. 6 is a basic block diagram of the proposed scheme.

[Explanation of symbols]

 1 Microphone 2 Transmitter attached to microphone 1 3A 1st receiver 3B 2nd receiver 3C 3rd receiver 4 Camera 5A 1st reception angle measurement part 5B 2nd reception angle measurement part 5C 3rd reception angle measurement part 6 Signal control unit 7 Information control unit 8 Main storage unit

Claims (2)

[Claims] 1. A video conferencing system using video such as moving images or still images between remote places, in which coordinate data of each seated position of a conference participant is stored, and voice is detected to make a corresponding statement. In the voice-tracking automatic aiming method that calculates the distance between the speaker and the camera using the coordinate data of the seating position of the person and controls the camera to the optimum aiming position and direction, it is provided for each seating position of the conference participants. Each microphone is equipped with a transmitter that emits a unique radio signal, and the camera is mounted at a fixed position in front of the entire seat, and the camera is fixed at three positions fixed on the vertical plane facing the seat. Attaching a camera that captures the same speaker as the camera at a fixed position in front of the seat, with the position of the camera as the origin of the three-dimensional coordinates, the direction toward the center of the seat is the Y axis, and the up and down direction is the Z axis. , A direction perpendicular to the Y-axis and the Z-axis is defined as the X-axis, and the signal of the transmitter is received at three positions fixed to the camera on a two-dimensional plane of the X-axis and the Z-axis including the position of the camera. Dimensional receivers are arranged, the coordinate values of each of the receivers are set in the main storage unit, the receivers are provided corresponding to the three receivers, control the corresponding receivers, and receive angles of received signals. A reception angle measuring unit for measuring the reception angle, a signal control unit for identifying and outputting a reception signal and reception angle information from each reception angle measurement unit, each reception signal and reception angle information from the signal control unit, and An information control unit that calculates the position of each transmitter as a three-dimensional coordinate value by using the coordinate value of each receiver in the main storage unit and stores it in the main storage unit is provided. It is characterized by driving the transmitters attached to the to obtain the three-dimensional coordinates of each transmitter. Three-dimensional coordinate Automatic Measurement Method for audio tracking type automatic aiming system that. 2. The signal generated from a transmitter attached to each of the microphones according to claim 1,
When radio signals having different frequencies or amplitudes or radio signals modulated with different digital codes are used to simultaneously transmit from the transmitters attached to the plurality of microphones, the reception angle measuring units receive the signals. A three-dimensional coordinate automatic measurement method in a voice tracking type automatic aiming method, which is characterized by identifying signals and measuring a reception angle of each received signal.