JP2014119699A - Camera universal head device, and angle correction method of pan and tilt function of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera universal head that absorbs an individual difference in a camera and/or a mechanism accuracy error, and enables improvement in reproducibility of a preset photography.SOLUTION: The camera universal head device including a universal head and an image pickup device comprises: tilt angle storage means that, at a third pan angle, stores a tilt angle in displaying a first index to a first position as a first tilt angle and, at a pan angle panned and inverted from the third pan angle, stores a tilt angle in displaying the first index to the first position as a second tilt angle; pan angle storage means that, at a third tilt angle, stores a pan angle in displaying a second index to a second position as a first pan angle and, at a tilt angle tilted and rotated to a position symmetry to a plane including a pan rotary shaft with respect to the third tilt angle, stores a pan angle in displaying the second index to the second position as a second pan angle; and control means that calculates and holds a tilt correction angle on the basis of the first and second tilt angles, calculates and holds a pan correction angle on the basis of the first and second pan angles, and controls a pan and tilt function on the basis of a correction angle.

Description

  The present invention relates to a camera pan head device and an angle correction method for the pan / tilt function thereof, and more particularly to a camera pan head device in which panning and tilting rotation of a mounted photographing apparatus can be driven by remote operation, and pan / tilt rotation The present invention relates to a camera head device having a drive angle correction function and an angle correction method for a pan / tilt function of the camera head device.

  When using a camera head that can change the pan / tilt angle and freely change the shooting direction for surveillance purposes, video monitoring is performed by so-called preset shooting that stores multiple monitoring points in advance and reproduces them. Is called. As a realization method, the camera pan head or the operation device is provided with a storage means, and the pan and tilt angles and the zoom position when the monitoring object is photographed are stored therein. By operating the pan / tilt / zoom driving unit so as to be the same as the storage position at the time of reproducible shooting, it becomes possible to take a picture of the monitoring target portion. In surveillance shooting, it is common to perform presets by operating from a remote monitor room, so if the pan or tilt angle is shifted during maintenance of the camera platform, the stored preset position is set. It was necessary to set again, and a long working time was required.

  In Patent Document 1, when the attachment / detachment of the camera is detected, and there is a difference between the pan / tilt position recorded at the time of removal and the pan / tilt position at the time of resetting, the pan / tilt rotation means is controlled to adjust the deviation. There has been disclosed a technique for obtaining a state before the attachment / detachment of the camera by correcting.

JP 2007-65210 A

  In the prior art disclosed in Patent Document 1, the position recorded when the camera is removed is only the rotation angle with respect to the reference angle of the pan axis or the tilt axis. The tilt of the optical axis caused by the difference in the assembly accuracy of the image sensor in the camera and the camera housing accuracy is not taken into consideration. Therefore, although the position of the camera attached after the camera replacement is coincident with the recorded position, there is a possibility that the optical axis direction is changed and the target image cannot be obtained. . In this case, it is necessary to perform the angle storage setting for the number of shooting target positions according to the mounted camera. Further, the reference angle of the pan axis or the tilt axis has individual differences due to an attachment error between the angle sensor and the camera pan head frame, and the same inconvenience occurs when the camera pan head is replaced.

  Therefore, in the present invention, a simple index of the pan / tilt angle stored including the mechanism error and the optical axis deviation of the camera is photographed to correct the angle, and the individual difference of the camera and the mechanism accuracy error are absorbed, so that the preset photographing can be performed. Provided are a camera head device and an angle correction method for a pan / tilt function of the camera head device that can improve reproducibility.

  In order to achieve the above object, a camera head device of the present invention includes a pan head having a pan / tilt function and a photographing device provided in the pan head, and processes an image signal photographed by the photographing device. And a third pan angle from the tilt reference angle when the first index displayed by the image signal processing means is displayed at the first predetermined position in the captured image. The tilt rotation angle is stored as a first tilt angle, and the first index determined by the image signal processing means at the pan angle rotated by 180 ° from the third pan angle is included in the captured image. A tilt angle storage means for storing a tilt rotation angle from the tilt reference angle when displayed at the first predetermined position as a second tilt angle, and at a third tilt angle, the image signal By processing means When the determined second index is displayed at the second predetermined position in the captured image, the pan rotation angle from the pan reference angle is stored as the first pan angle, and the third tilt angle is stored. The second index determined by the image signal processing means is displayed at the second predetermined position in the photographed image at a tilt angle rotated to a position symmetrical to a plane including the pan rotation axis. The pan rotation angle from the pan reference angle at this time is stored as a second pan angle, and a pan angle storage means, and the tilt rotation angle is corrected based on the first tilt angle and the second tilt angle. Control means for calculating and holding an angle, calculating and holding a correction angle of a pan rotation angle based on the first pan angle and the second pan angle, and controlling a pan / tilt function based on the correction angle; .

  According to the method of the present invention, even if there is an individual difference in the structure of the chassis, since the video imaged on the basis of the chassis installation surface is viewed, the correction including the optical axis shift and the tilt of the camera base can be performed. Is possible. Therefore, not only when the camera is replaced, but also when the camera head is replaced, the existing shooting position preset value can be used with little error, and the camera head device and the camera head device that can improve the reproducibility of the shooting direction can be used. An angle correction method for the pan / tilt function can be provided.

It is a figure which shows the camera pan head system of an Example. It is a block diagram for demonstrating the operation | movement inside the camera pan head of an Example. It is a parameter | index (black-and-white chart) for the tilt angle correction of an Example. It is a figure for demonstrating the tilt angle correction | amendment procedure of an Example. It is a figure for demonstrating the tilt angle correction amount of an Example. It is an example of a video monitor display when an index is photographed with the camera platform of the embodiment. It is an example of a video monitor display when an index is photographed with the camera platform of the embodiment. It is an example of a video monitor display when an index is photographed with the camera platform of the embodiment. It is a figure for demonstrating the pan angle correction | amendment procedure of an Example. It is a parameter | index (black-and-white chart) for the pan angle correction of an Example. It is an example of a video monitor display when an index is photographed with the camera platform of the embodiment. It is an example of a video monitor display when an index is photographed with the camera platform of the embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a system diagram illustrating a camera pan head device that is remotely operated and has a pan / tilt function (pan function and tilt function) according to an embodiment of the present invention. A system overview of the camera head device of the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, the camera head device 1 of this embodiment in which a head device and a photographing device are connected to each other has a video output 16 for a video monitor (display device) 3 and a communication terminal 21 for a camera cloud. It is connected to an operating device 4 for performing pan / tilt / camera operation of the platform device 1. The video monitor 3 and the operating device 4 are often installed as a set apart from the camera pan head device 1, but the video signal and control signal transmission means are not related to the gist of the present invention, and thus are omitted.

The operation of the camera head device 1 will be described with reference to FIG.
The subject image picked up via the lens 11 is formed on the image pickup device 12 and picked up. The captured image signal is automatically adjusted to an appropriate level by the amplitude control amplifier 22, and then digitally processed in units of pixels in the image signal processing unit 13, and output from the video output terminal. The arithmetic processing circuit (CPU) 14 performs drive control of the zoom / focus drive unit, the tilt drive unit 17 and the pan drive unit 19 of the lens 11 in addition to the control of the image signal processing unit 13. Further, it has a function of writing the output detected by the tilt angle detector 18 and the pan angle detector 20 into the memory 15 as storage means, reading it out, and comparing it with the output from the angle detector. The communication terminal 21 connects the CPU 14 and the external operation device 4.

  The operation device 4 is a device for remotely operating the camera pan head device 1. P / T operation unit 41 for operating pan and tilt, zoom operation unit 42 for operating the zoom lens of the lens 11, set switches 45, 46, 47 for setting or reading preset positions 1, 2, 3 and triggers for storing A memory switch 44 is provided.

  In order to perform presetting, first, the pan / tilt driving unit of the camera pan head device 1 is operated by operating the P / T operation unit 41 of the operation unit 4 so that the camera is directed to the shooting target so that an appropriate angle of view is obtained. The zoom lens is moved by operating the zoom operation unit 42. Next, the switch having the number to be stored is selected from the switches 45 to 47 and pressed, and then the memory switch 44 is pressed. Thus, the preset positions (pan angle, tilt angle, zoom position) are stored in the storage means (not shown) inside the controller in association with the switch of the controller. Note that the preset position storage means is described as being inside the controller, but this may be provided in the camera pan head apparatus.

  FIG. 3 shows a simple index 5 (first subject, second subject) photographed when angle correction is performed, and is divided into two parts in black and white.

  The correction procedure will be described with reference to FIG. Although the camera pan head device 1 is attached to the ceiling and omitted in FIG. 4, the video monitor 3 and the operation device 4 are connected as in FIG. 1, and the video captured by the camera pan head device 1 is video monitor. It is assumed that panning, tilting, and zooming operations can be performed while viewing the screen. The index 5 in FIG. 3 is assumed to be placed in the direction 24 in FIG. The index 5 is assumed to be installed at a position away from the extension of the pan rotation axis of the camera pan head device 1. Further, at that position, the boundary line in the index 5 (in the example shown in FIG. 3, the black and white boundary line) (first index, first boundary line) intersects the plane including the pan rotation axis. The index 5 is arranged so that it is not in the plane. FIG. 5 is a diagram for explaining the tilting operation of the camera pan head, and the angle deviation is exaggerated.

  First, the P / T operation unit 41 of the operation device is operated, and a command is issued from the operation device 4 to the CPU 14 of the camera platform device 1 so that the image sensor 12 faces in the direction of 24, and the pan driving unit and the tilt driving unit are operated. Let By gradually tilting up and operating the zoom operation unit 42, the operation unit 4 moves to the CPU 14 of the camera platform 1 so that the index 5 is reflected in the entire display area on the video monitor 3 as shown in FIG. A command is issued to operate the zoom drive unit of the lens 11.

  In the image signal processing unit 13, the RGB signals from the image sensor 12 are calculated in the scanning order, digitally processed into luminance signals and color difference signals in units of pixels, and converted into a prescribed video format in the order of video lines. For example, in the case of a 1080 / 30p system defined by SMPTE (Society of Motion Pictures and Television Engineers) 274M, one frame image is formed by 1920 pixels of luminance signal data and color difference signal data for 1080 lines. . When attention is paid only to the luminance signal, it is expressed with a resolution of 10 bits per pixel. Generally, automatic gain control (AGC) or automatic exposure adjustment (AE) by lens aperture control is performed so that the upper limit of the effective area is the maximum luminance (white) so that 10 bits are used effectively.

  By performing such automatic control of the video level, if the luminance level is expressed by 1 bit, the bright color with high luminance is 1 and the dark color with low luminance is 0, and the maximum of the 10-bit luminance data. Matches the upper bit.

  When the index 5 is photographed in the state shown in FIG. 6, the most significant bit of the luminance data of the pixel showing the white part is 1, and the most significant bit of the luminance data of the pixel showing the white part is 0. Here, a specific line in the photographed image, for example, a 540 line substantially at the center of the screen is set as a detection reference (first predetermined position). Here, by counting the number of the most significant bits of the luminance data, the image signal processing unit 13 (video line detection means) determines (detects) that the index reference (white and black changing point) is located on the line. can do. In the example shown in FIG. 5, since the tilt is gradually increased, the most significant bit of the luminance data of all the pixels is initially 0, but after passing through the white and black change points, the most significant bit of the luminance data is 1. It becomes. The tilt rotation angle when the number of pixels that become 1 exceeds 1/2 of the number of pixels 1920 in one line, that is, 960, is detected by the tilt angle detector 18, and the memory 15 (tilt angle storage means) is detected via the CPU 14. Is stored as the first tilt angle A (FIG. 5) of the designated video line. On the video monitor 3, for example, the center of the index is displayed as shown in FIG. Here, the tilt angle is an angle with respect to the reference angle 0 ° (25 in FIG. 5) of the angle detector 18, and the reference angle has an angular deviation of C with respect to the vertical direction.

  Next, the tilt drive unit 17 is driven by operating the P / T operation unit 41, and the image sensor is placed in the direction 26 in which the tilt rotation angle is −A with respect to the tilt reference angle 0 ° (direction 25 in FIG. 5). Turn. Thereafter, the P / T operation unit 41 of the operation device 4 is panned while maintaining the tilt angle, and is rotated by 180 ° from the current pan angle (third pan angle). The inclination of the reference angle from the vertical direction is also shifted by 180 ° to 27 directions, and the lens 11 faces 28 directions. When the reference angle (directions 25 and 27) of the tilt angle detector 18 coincides with the pan rotation axis, the image on the image monitor 3 is an image obtained by vertically inverting FIG. 7 as shown in FIG. However, in consideration of the mounting error of the tilt angle detector 18, the mechanical accuracy of the camera head device 1, the levelness of the installation surface, etc., this is rare. The tilt reference angle including the error and accuracy and the vertical deviation angle C (FIG. 5) are obtained by converting the difference between the index reference (change point between black and white) in FIG. 8 and the index reference in FIG. 7 into an angle. Can be sought. The tilt drive unit 17 is operated by operating the P / T operation unit 41 of the operation unit 4 so that the index reference appears in the vicinity of the center in the photographed image (as shown in FIG. 8, the image is inverted upside down in FIG. 7). Drive. In the first designated video line (540 lines), the tilt angle detector 18 determines the tilt angle when the number of pixels in which the most significant bit of the luminance data is 0 exceeds 960 pixels in one line. The tilt angle is detected as -B. As is clear from FIG. 5, 1/2 of the sum of the first tilt angle A and the second tilt angle −B is the angle that is the initial tilt reference angle and the vertical shift angle, and is the angle to be corrected. C.

  As a correction method in the present embodiment, moving the reference angle of the tilt angle detector 18 is not realistic. Therefore, the offset angle C to be corrected by the CPU 14 is held, and the angle deviation can be eliminated by controlling the angle obtained by adding the offset angle C to the output of the tilt angle detector 18 as the angle to be rotated. .

  In the above-described method, from the state in which the optical axis of the photographing apparatus is in the direction of 24, a tilt operation is performed to invert the direction 25 by A, and then the panning is rotated by 180 °, and then the directions 28 to 24 are performed. The angle B was obtained by tilting to the position and specifying the index 5. However, the effect of the present invention is not limited to the pan / tilt operation sequence described above, and the index 5 is specified by rotating the pan 180 ° from the state in which the optical axis of the photographing apparatus faces the direction of 24. The angle B can also be obtained by rotating the tilt until As an angle detection method, the rotation angle sensor is provided on the rotation shaft and the detection output is always used. However, the amount of movement from the reference position is the number of steps of the pulse motor required to move. It can also be obtained by converting to a corner. In addition, the video format and specific numerical values have been described for explaining the basic concept, but the present invention is not limited to these values and embodiments. 6 to 8 show that the index reference is projected horizontally on the screen, it may be tilted. As described above, the index 5 is installed at a position deviating from the direction of the pan rotation axis of the camera pan head device 1, and the boundary line to be recognized within the index 5 intersects the plane including the pan rotation axis ( If the index 5 is arranged so that it is not in a plane, the effect of the present invention can be obtained.

  Next, the correction of the pan angle will be described with reference to FIG. In general, the pan rotation axis is fixed with respect to a predetermined reference object (such as a structure) that does not move, and the tilt rotation axis is substantially perpendicular to the pan rotation axis and rotates by pan rotation. The tilt correction described above was corrected so as to be based on the vertical direction (pan rotation axis direction). The correction of the pan angle described here is to relatively correct an optical axis shift caused by a difference in camera mounting accuracy and the like, in which the optical axis of the photographing apparatus is deviated from the vertical with respect to the tilt rotation axis.

  Ideally, the optical axis of the photographing apparatus is installed so as to be perpendicular to the tilt rotation axis. However, if the mounting accuracy of the photographic device in the camera pan head device or the mounting accuracy of the camera and pan head housing is poor, individual differences may occur and the same preset position may be given, and the camera may turn in different directions. For example, a certain image cannot be obtained. FIG. 9 exaggerates the case where the optical axis of the photographing apparatus and the tilt rotation axis are not perpendicular. FIG. 10 shows an index used for correcting the pan angle, which is obtained by rotating the index shown in FIG. 3 by 90 °. In the correction for the pan angle, the index to be used may be arranged so that the projected image of the pan rotation axis on the index plane is not perpendicular to the black and white boundary line.

  First, a specific pixel row, for example, a 960 pixel row of each line at the center of the screen is set as a detection reference (second predetermined position), and the index reference is obtained by counting the number of the most significant bits of the luminance data. (Change point between white and black) (second index, second boundary line) can be detected. As in the case of tilt angle correction, the most significant bit of luminance data for white pixels is 1, and the most significant bit of luminance data for black is 0. The P / T operation unit 41 of the operation device 4 is operated to operate the pan driving unit 19 in the direction in which white increases from the side where black appears, and the image signal processing unit 13 (pixel group detection means) Is detected when the number of effective lines exceeds ½ of 1080, that is, 540. The pan angle at that time is detected by the pan angle detector 20 and stored as the first pan angle P of the designated pixel group in the memory 15 (pan angle storage means) via the CPU 14. In FIG. 9, it corresponds to the optical axis 51 and becomes a display screen of a video monitor as shown in FIG.

  Next, tilt drive is performed from the current tilt angle (third tilt angle) to a position that is symmetric with respect to a plane including the pan rotation axis by operation of the operation unit 4. In FIG. 9, when the optical axis is moved from 51 to 52 with respect to the tilt reference angle (vertical direction in the plane including the pan rotation axis) from + 90 ° to −90 ° in order to simplify the drawing. Is shown. Further, when the pan is rotated 180 ° from the position of the optical axis 52 by the operation of the operation unit 4 in the next step, the optical axis becomes the direction of 53. On the video monitor, the index displayed in FIG. 11 appears upside down as shown in FIG. 12, and the index reference (white and black change point (second index)) is the optical axis of the photographing apparatus. Is displayed with a deviation from the center by the amount of the deviation from the vertical to the tilt axis.

In order to obtain the correction angle, the P / T operation unit 41 of the operation device 4 is operated, the pan driving unit 19 is operated in a direction in which black increases, and the number of pixels that become 0 is 1/2 of the number of effective lines 1080, that is, 540. The pan angle detector 20 detects the pan angle when the number exceeds the number. This angle is set as the second pan angle Q of the designated pixel group. The correction angle R to be obtained is R = (P−180 ° −Q) / 2 as apparent from FIG.
It becomes.

  The correction angle R of the pan angle is held by the CPU 14 and applied to the pan rotation angle with the reverse sign with the tilt rotation angle of 0 ° as a boundary so that the optical axis direction of the photographing apparatus deviates from the vertical with respect to the tilt rotation axis. Even in the case of attachment, the pan rotation angle can be appropriately corrected.

  As a correction method in this example, the angle deviation is eliminated by using as the true angle the CPU 14 the angle obtained by subtracting the offset angle R from the pan reference angle with respect to the output of the pan angle detector 20.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

DESCRIPTION OF SYMBOLS 1 ... Camera head apparatus 13 ... Image signal processing part (image signal processing means)
14: Arithmetic processing circuit (control means)
15. Memory (tilt angle storage means, pan angle storage means)

Claims (9)

A camera pan head device including a pan head having a pan / tilt function and a photographing device mounted on the pan head,
Image signal processing means for processing an image signal photographed by the photographing device;
At the third pan angle, the tilt rotation angle from the tilt reference angle when the first index is displayed at the first predetermined position in the captured image, determined by the image signal processing means, is set to the first pan angle. And the first index determined by the image signal processing means at the first predetermined position in the photographed image at a pan angle rotated by 180 ° from the third pan angle. Tilt angle storage means for storing a tilt rotation angle from the tilt reference angle when displayed as a second tilt angle;
At the third tilt angle, the pan rotation angle from the pan reference angle when the second index is displayed at the second predetermined position in the captured image, which is determined by the image signal processing means, And the second index determined by the image signal processing means at the tilt angle rotated to a position symmetrical to a plane including the pan rotation axis with respect to the third tilt angle. Pan angle storage means for storing a pan rotation angle from the pan reference angle when displayed at the second predetermined position in a captured image as a second pan angle;
A tilt rotation angle correction angle is calculated and held based on the first tilt angle and the second tilt angle, and a pan rotation angle correction angle is calculated based on the first pan angle and the second pan angle. Control means for controlling the pan / tilt function based on the correction angle;
A camera pan head device comprising: The image signal processing means includes
Video line detection means for detecting that the first index is displayed at the first predetermined position in a captured image when the tilt is rotated at the first pan angle;
Pixel group detection means for detecting that the second index is displayed at the second predetermined position in the captured image when panning at the third tilt angle;
The camera head device according to claim 1, comprising:   The video line detection unit determines whether the first index is displayed on the predetermined video line according to the number of 1 or 0 of the most significant bit of luminance data of pixels of the predetermined video line. The camera pan / tilt head apparatus according to claim 2.   The pixel group detection means determines whether the first index is displayed on the predetermined pixel group based on the number of 1 or 0 values of the most significant bits of luminance data of the pixels of the predetermined pixel group. The camera pan / tilt head device according to claim 2 or 3, wherein An angle correction method for a pan / tilt function in a camera pan / tilt head apparatus including a pan / tilt function pan / tilt head and a photographing device provided on the pan / tilt head,
Driving the camera platform so that the first subject is displayed at a first predetermined position in the captured image;
The tilt rotation angle from the tilt reference angle is stored as the first tilt angle,
Rotate 180 ° pan,
Tilt rotation to display the first subject at the first predetermined position in the captured image,
Storing a tilt rotation angle from the tilt reference angle as a second tilt angle;
Correcting a tilt rotation angle based on the first tilt angle and the second tilt angle;
Driving the camera platform so that the second subject is displayed at a second predetermined position in the captured image;
The pan rotation angle from the pan reference angle is stored as the first pan angle,
Tilt to a position symmetrical to the plane including the pan rotation axis,
Pan the pan so that the second subject is displayed at the second predetermined position in the captured image,
The pan rotation angle from the pan reference angle is stored as the second pan angle,
Correcting a pan rotation angle based on the first pan angle and the second pan angle;
An angle correction method for a pan / tilt function in a camera head device.   6. The camera pan head apparatus according to claim 5, wherein when the first tilt angle is A and the second tilt angle is B, the tilt reference angle is corrected by (A + B) / 2. Angle correction method for pan / tilt function.   The pan reference angle is corrected by (P-180 ° -Q) / 2 where P is the first pan angle and Q is the second pan angle. An angle correction method for a pan / tilt function in a camera pan / tilt function of the camera pan / tilt apparatus described above.   The first subject is disposed at a position deviated from the extension of the pan rotation axis, includes a first boundary line serving as an index, and the first boundary line intersects a plane including the pan rotation axis. 8. The angle correction method for the pan / tilt function in the camera pan head device according to claim 5, wherein the pan / tilt function is arranged.   The second subject includes a second boundary line serving as an index, and is arranged so that a projection image of the pan rotation axis on a plane including the second boundary line is not perpendicular to the second boundary line 9. The angle correction method for the pan / tilt function in the camera pan / tilt head device according to claim 5, wherein the pan / tilt function is corrected.

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