Abstract:
A monitoring camera apparatus includes: a video camera; a panning mechanism; and a tilting mechanism; and automatic pivoting portion for operating the panning mechanism to pan the video camera by a predetermined pan (tilt) angle or to a predetermined pan (tilt) angle position when the video camera reaches the predetermined vertical (horizontal) position and a tilt command is inputted. The predetermined vertical position may be determined when the video camera directs the downward in the vertical direction. The auto-pivoting function may be started in response to both predetermined pan and tilt positions. During the auto-pivoting, controlling the video signal processing is stopped, pan and tilt speed is set to maximum, the direction of panning may be judged when the predetermined angle position is set. After auto-pivoting, tilt is made upwardly though the tilt command indicates downward and the screen image may be inverted and the pan and tilt positions are held until pan (tilt) command is inputted. The predetermined pan (tilt) angle and auto-pivoting mode set/reset may be set externally.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a monitoring video camera apparatus for taking an image and outputting a video signal with tilt and pan control. 
     2. Description of the Prior Art 
     A monitoring video camera apparatus including a video camera and a tilting/panning mechanism for generating a video signal to provide a monitor image on a display monitor which is remote from the video camera is known. 
     International Publication Number WO 95/35624 discloses a surveillance camera system including such a prior art monitoring video camera apparatus. This surveillance camera system includes an auto-pivot feature for automatic pivoting of the camera when the camera is in a vertical position. 
     SUMMARY OF THE INVENTION 
     The aim of the present invention is to provide a superior monitoring video camera apparatus. 
     According to the present invention there is provided a first monitoring camera apparatus including: a video camera for taking an image around the video camera and generating a video signal from the image; a panning unit for panning the video camera in the horizontal direction in response to a pan command from an external controller; a tilting unit for tilting the video camera in the vertical direction in response to a tilt command from the external controller; a detector for detecting that the video camera reaches a predetermined vertical position of the video camera; and an automatic pivoting portion responsive to the tilt command and the detector for operating the panning unit to pan the video camera by a predetermined pan angle when the video camera reaches the predetermined vertical position and the tilt command is inputted. 
     In the first monitoring camera apparatus, the tilt command includes a speed command and the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle when the video camera reaches the predetermined vertical position, the tilt command is inputted, and the speed command indicates a speed higher than a predetermined speed. 
     The first monitoring camera apparatus, may further include a video camera control portion for controlling a video signal generating condition in accordance with a control signal, wherein the automatic pivoting portion operates the video camera control portion to hold the video signal generating condition while the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle. 
     In the first monitoring camera apparatus, the automatic pivoting portion operates the panning unit at a maximum panning speed. 
     In the first monitoring camera apparatus, the automatic pivoting portion operates the tilting unit to tilt the video camera upwardly in response to that the automatic pivoting has panned the video camera by the predetermined angle. 
     The first monitoring camera apparatus may further include a video signal converting circuit for converting the video signal to invert an screen image of the video signal in response to the automatic pivoting unit. 
     In the first monitoring camera apparatus, the predetermined position is determined by that the video camera is just downwardly directed in the vertical direction by the tilting unit. 
     The first monitoring camera apparatus may further include a receiving and storing portion for receiving and storing angle data and the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle determined by the angle data from the receiving and storing portion. 
     In the first monitoring camera apparatus, the predetermined pan angle is 180°. 
     In the first monitoring camera apparatus, the automatic pivoting portion keeps to stop the panning and tilting units when the automatic pivoting portion completes operating the panning unit to pan the video camera by the predetermined pan angle until both stop commands for the tilting unit and the panning unit are inputted. 
     The first monitoring camera apparatus may further include a receiving and storing portion for receiving and enable/disable data indicative of enabling and disabling the automatic pivoting portion, the automatic pivoting portion either operates or does not operate the panning unit to pan the video camera by the predetermined pan angle in accordance with the enable/disable data when the video camera reaches the predetermined vertical position and the tilt command is inputted. 
     According to the present invention there is also provided a second monitoring camera apparatus including: a video camera for taking an image around the same and generating a video signal from the image; a panning unit for panning the video camera in the horizontal direction in response to a pan command from an external controller; a tilting unit for tilting the video camera in the vertical direction in response to a tilt command from the external controller; a detector for detecting that the video camera reaches a predetermined vertical position of the video camera; and an automatic pivoting portion responsive to the tilt command and the detector for operating the panning unit to pan the video camera to a predetermined pan angle position when the video camera reaches the predetermined vertical position and the tilt command is inputted; and a judging portion for judging one of pan directions to provide a less panning angle from the present position and the predetermined angle position, wherein the automatic pivoting portion operates the panning unit to pan the video camera in the one of pan directions from the judging portion. 
     According to the present invention there is also provided a third monitoring camera apparatus including: a video camera for taking an image around the same and generating a video signal from the image; a panning unit for panning the video camera in the horizontal direction in response to a pan command; a horizontal detector for detecting that the video camera reaches a predetermined horizontal position of the video camera to generate a horizontal position detection signal; a tilting unit for tilting the video camera in the vertical direction in response to a tilt command; a vertical detector for detecting that the video camera reaches a predetermined vertical position of the video camera to generate a vertical position detection signal; and an automatic pivoting portion responsive to the tilt command, the pan command, the horizontal detector, and the vertical detector for operating the panning unit to pan the video camera by a predetermined pan angle and operating the tilting unit to tilt the video camera by a predetermined tilt angle when the video camera reaches a predetermined horizontal position of the video camera, the video camera reaches the predetermined vertical position of the video camera, the pan command is inputted, and the tilt command is inputted. 
     In the third monitoring camera apparatus, the tilt command includes a tilt speed command and the pan command includes a pan speed command and the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle and operates the tilting unit to tilt the video camera by the predetermined tilt angle when the video camera reaches a predetermined horizontal position of the video camera, the video camera reaches the predetermined vertical position of the video camera, and the pan command and the tilt commands are inputted. 
     The third monitoring camera apparatus may further include a video camera control portion for controlling a video signal generating condition of the video camera in accordance with a control signal, wherein the automatic pivoting portion operates the video camera control portion to hold the video signal generating condition while the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle and operates the tilting unit to tilt the video camera by the predetermined tilt angle. 
     In the third monitoring camera apparatus, the automatic pivoting portion operates the panning unit at a maximum panning speed and operates the tilting unit at a maximum tilting speed. 
     The third monitoring camera apparatus may further include a receiving and storing portion for receiving and storing angle data, wherein the automatic pivoting portion operates the panning unit to pan the video camera by the predetermined pan angle determined by the angle data from the receiving and storing unit. 
     In the third monitoring camera apparatus, the predetermined pan angle may be 180°. 
     In the third monitoring camera apparatus, the automatic pivoting portion may keep stopping the panning and tilting units when the automatic pivoting portion completes operating the panning unit to pan the video camera by the predetermined pan angle and completes operating the tilting unit to tilt the video camera by the predetermined tilt angle until both stop commands for the tilting unit and the panning unit are inputted. 
     The third monitoring camera apparatus may further include a receiving and storing portion for receiving and storing enable/disable data indicative of enabling and disabling the automatic pivoting portion, the automatic pivoting portion either operates or does not operate the panning unit to pan the video camera by the predetermined pan angle in accordance with the enable/disable data when the video camera reaches the predetermined vertical position and the tilt command is inputted. 
     According to the present invention there is further provided a fourth monitoring camera apparatus including: a video camera for taking an image around the same and generating a video signal from the image; a panning unit for panning the video camera in the horizontal direction in response to a pan command from an external controller; a tilting unit for tilting the video camera in the vertical direction in response to a tilt command from the external controller; a detector for detecting that the video camera reaches a predetermined vertical position of the video camera and to a predetermined horizontal position of the video camera; an automatic pivoting portion responsive to the tilt command and the detector for operating the panning unit to pan the video camera to a predetermined pan angle position when the video camera reaches the predetermined vertical position and reaches the predetermined horizontal position and the tilt command is inputted; and a judging portion for judging one of pan directions to provide a lower panning angle from the the predetermined horizontal position and the predetermined pan angle position, wherein the automatic pivoting portion operates the panning portion to pan the video camera in the one of pan directions from the judging portion. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The object and features of the present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
     FIG. 1 is a block diagram of a video monitoring system including a video camera apparatus of the first embodiment; 
     FIG. 2 depicts a flow chart of the first embodiment showing an operation of a microprocessor shown in FIG. 1; and 
     FIG. 3 depicts a flow chart of a second embodiment showing an operation of the microprocessor shown in FIG.  1 . 
     The same or corresponding elements or parts are designated with like references throughout the drawings. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereinbelow will be described a first embodiment of this invention. 
     FIG. 1 is a block diagram of a video monitoring system including a video camera apparatus of the first embodiment. 
     The video monitoring system includes a video camera apparatus  36  for taking an image around the same and generating a video signal, a display monitor  16 , and a controller  17  for generating a command supplied to the video camera apparatus. 
     The monitoring video camera apparatus  36  of the first embodiment includes a camera unit  3 , a tilting unit  33  for tilting the camera unit  3 , a pan unit  34  for panning the camera unit through the tilting unit  33 , a camera control circuit  11  for controlling the camera unit  3 , a tilt motor control circuit  12 , a pan motor control circuit  13 , a microprocessor  14  (MPU), a video signal processing circuit  15  for processing an image signal from the camera unit  3  and generating a video signal, and a memory  18  for storing data. 
     The camera unit  3  includes a zoom lens unit  1  and a CCD image sensor  2 . The zoom lens unit  1  receives the image and forms the image on the CCD image sensor  2  which generates the image signal supplied to the video signal processing circuit  15  which processes the image signal and generates the video signal  15   a  supplied to the display monitor  16  which provides a reproduced video image to a monitoring operator. 
     The camera control circuit  11  generates camera control signals to drive the CCD image sensor  2  and control a zoom ratio, a diaphragm. Similarly, the microprocessor  14  also generates video control signal supplied to the video signal processing circuit  15  such as white balance, gradation compensation, AGC, a motion detection, alarm generation, or the like. 
     The panning unit  34  includes a pan motor  8 , a drive gear  7 , a pan gear  6 , arms  4 , and a base plate  10 . The pan motor control circuit  13  controls the pan motor  8 . The pan motor  8  drives the pan gear  6  through the drive gear  7 . The pan gear  6  supports the arms  4  which support the tilting unit  33 . The base plate  10  supports the pan motor  8  and rotatably supports the pan gear  6 . 
     The tilting unit  33  tilts the camera unit  3  and includes a tilt motor  5  supported by the arm  4  for rotating a shaft  37  which is supports the camera unit  3 . The tilt motor control circuit  12  drives the tilt motor  5  under control by the microprocessor  14 . 
     The video signal processing circuit  15  includes a video signal generation circuit  41  for generating the video signal from an image signal from the image sensor  2 , a memory circuit  35  for storing the video signal from the video signal generation circuit  41  and reading the stored video signal to provide the output video signal  15   a  of which screen image is made a usual screen image, a mirror image, upside-down image, or a screen image inverted in the horizontal and vertical under control by the microprocessor  14 , a motion detection circuit  42  for detecting a motion in the screen image between the present image and the past image, and an alarm circuit  43  responsive to the motion detection circuit  42  for generating an alarm signal when a motion is detected under the control by the microprocessor  14 . The alarm signal is sent to the monitoring side, that is, a speaker  44  or the like to inform the alarm to the monitoring operator. As mentioned above, the microprocessor  14  generates the video control signal supplied to the video signal processing circuit  15  to control white balance, gradation compensation, AGC in the video signal generation circuit  41  and a motion detection in the motion detection circuit  42 , the alarm generation in the alarm circuit  43 . 
     The microprocessor  14  controls the camera control circuit  11 , a tilt motor control circuit  12 , the pan motor control circuit  13 , and the video signal processing circuit  15  in response to the commands from the controller  17 . 
     An arm  21  is fixed to an tilt axis  37  coupled to the tilt motor  5 . An end of the arm  21  supports a magnet  22   a.  On the other hand, one of the arms  4  supports a Hall element  22   b  which is arranged to confront the magnet  22   a  at a predetermined vertical position. The magnet  22   a  and the Hall element  22   b  forms a vertical position sensor  22 . The arm  21  is fixed such that the magnet  22   a  confronts the Hall element  22   b  when the camera unit  3  downwardly directs to the vertical direction C. This position is referred to as an auto-pivoting start position. The detection signal  22   c  is supplied to the microprocessor  14  through the tilt motor control circuit  12 . 
     A slip ring  9  transmits signals between the camera control circuit  11  and the camera unit  3 , between the tilt motor control circuit  12  and the tilt motor  5 , between the vertical position sensor  22  and the microprocessor  14  through the tilt motor control circuit  12  to provide 360° panning. 
     A shaft  38  coupling the pan motor  8  to the drive gear  7  holds a magnetic gear  23   a  having teeth generating a magnetic field distribution pattern of which intensity of the magnetic field equi-angularly varies along the peripheral of the magnetic gear  23   a  to provide the panning angle. The base plate  10  supports a magnetic pickup  23   b  for detecting a magnetic field of the magnetic filed distribution pattern. A current is induced in the magnetic pickup  23   b  in response to confronting each tooth of the magnetic gear  23   a  as a horizontal position signal supplied to the microprocessor  14 . The microprocessor  14  counts the pulses in the horizontal position signal to detect the panning angle and the pan angle position. 
     The monitoring operator operates the controller  17  with watching the display monitor  16 . If a person walks on the passage from the door  31  to the door  32 , the monitoring operator directs the camera unit  3  to the door  31  by operating the joystick  17   b  and directs an optical axis of the camera unit  3  to the person waking on the passage  30  by joystick  17   b  with controlling the tilt motor  5  and the pan motor  8 . The operator can sets the automatic pivoting function by sending mode data indicative of a 180°-automatic panning mode, a desired angle panning mode with desired angle data or a desired angle position mode with desired angle position data to the microprocessor  14 . The microprocessor  14  receives and stores the mode data and the accompanied data in the memory  18  and effects one of the automatic pivoting modes in accordance with the mode data in the memory  18 . 
     FIG. 2 depicts a flow chart of the first embodiment showing the operation of the microprocessor  14 . 
     The controller  17  generates and transmits the command in response to operation keys  171  and a joystick  17   b.    
     The microprocessor  14  effects the operation shown in FIG. 2 in response to the command from the controller  17 . 
     At first, the microprocessor  14  checks whether there is the automatic pivoting set/reset (enable/disable) command from the controller  17 . If there is the automatic pivoting set/reset command from the controller  17  the microprocessor  14  stops the pan motor  8  and the tilt motor  5  in step s 2 . Then, if the automatic pivoting function has been reset, the microprocessor  14  sets the automatic pivoting function in step s 3 . If the automatic pivoting function has been set, the microprocessor  14  resets the automatic pivoting function in step s 3  in response to the automatic pivoting set/reset command. 
     In step s 1 , if there is not the automatic pivoting set/reset command from the controller  17 , the microprocessor  14  checks whether there is downward tilt operation command in step s 4 . If there is not a downward tilt operation command in step s 4 , the microprocessor  14  controls the pan motor  8  and the tilt motor  5  in step s 16 . If there is the downward tilt operation command in step s 4 , the microprocessor  14  checks whether the vertical position sensor  22  detects the vertical position in step s 5 . If the vertical position sensor  22  does not detect the predetermined vertical position, the microprocessor  14  controls the pan motor  8  and the tilt motor  5  in accordance with the pan speed command and the tilt speed command respectively included in the pan operation command and the tilt operation command from the controller  17  in step s 17 . If the vertical position sensor  22  detects the predetermined vertical position, the microprocessor  14  stops the tilt motor  5  but controls the pan motor  8  in accordance with the pan speed command in step s 6 . Then, the microprocessor  14  checks whether setting the automatic pivoting function (enable) has been maintained in step s 7 . If setting the automatic pivoting function has been not maintained (disable), processing returns to step s 1 . If setting the automatic pivoting function is maintained (enable), the microprocessor  14  waits for 200 m sec in step s 8 . 
     In the following step s 9 , the microprocessor  14  checks whether the tilt speed command indicating downward direction is successively inputted from just before the predetermined vertical position. If the tilt speed command indicating downward direction is not successively inputted from just before the vertical position, processing returns to step s 1 . If the tilt speed command indicating downward direction is successively inputted from just before the predetermined vertical position, the microprocessor  14  stops (disable) the motion detection and alarm functions or the like in step s 10 . 
     In the following step s 11 , the microprocessor  14  operates the pan motor control circuit  13  to pan the camera unit  3  by a predetermined pan angle (to a predetermined pan angle position in accordance with the mode data) with observing the output of the horizontal position sensor  23  and then stops the pan motor  8 . Then, the microprocessor  14  waits for 100 msec in step s 12 . 
     In the following step s 13 , the microprocessor  14  operates (enables) the motion detection function and the alarm output functions or the like. Then, the microprocessor  14  checks whether the tilt speed command indicating downward direction is successively inputted. If the tilt speed command indicating downward direction is not successively inputted, processing returns to step s 1 . If the tilt speed command indicating downward direction is successively inputted, the microprocessor  14  operates the tilt motor control circuit  12  to upwardly tilt the camera unit  3  at a predetermined tilting speed, wherein panning is effected as commanded. Moreover, the video screen image is inverted by the video signal processing circuit  15  with the memory circuit  35 . Then, processing returns to step s 14 . In step s 14 , if the tilt speed command indicating downward direction is successively inputted, the microprocessor  14  continues the operation in step s 15 . If the tilt speed command indicating downward direction is not successively inputted, processing returns to step s 1 . 
     In step s 11 , if mode data indicating the 180°-automatic panning mode is stored in the memory  18 , the microprocessor  14  pans the video camera by 180°, and if mode data indicating the desired angle panning mode is stored in the memory  18 , the microprocessor  14  pans the video camera by the desired angle in accordance with the desired angle data from the memory  18 . Moreover, if the mode data indicating the desired angle position mode is stored in the memory  18 , the microprocessor  14  pans the video camera to the desired angle position in accordance with the desired angle position data from the memory  18 . 
     If the memory  18  stores the mode data indicating the 180°-automatic panning mode or a desired angle panning mode is stored in the memory  18 , the microprocessor  14  pans the video camera unit  3  at a maximum panning speed. If the memory  18  stores the mode data indicating the desired angle position mode, the microprocessor  14  judges one of panning directions to provide a smaller panning angle and a short panning interval from the present pan angle position (the auto-pivoting start position) and the desired angle position data. Then, the microprocessor  14  operates the panning unit  34  to pan the video camera unit  3  in the judged pan direction in step s 11 . 
     In step s 15 , the microprocessor  14  controls the video signal processing circuit  15  including the memory circuit  35  to invert the screen image of the video signal and outputs the video signal of which screen image is inverted. That is, the screen image is made upside down or made a mirror image, or inverted in the vertical and horizontal directions. 
     Second Embodiment 
     The video monitoring camera apparatus of a second embodiment is substantially the same as that of the first embodiment. The difference is that the auto-pivoting function is effected in response to the pan operation command, the tilt operation command, detection of a predetermined vertical position and detection of a predetermined horizontal position and the automatic tilting is further effected in addition to panning of the auto-pivoting function. That is, when the camera unit  3  is directed to the door  31 , the auto-pivoting function including panning and tilting is performed. In the second embodiment, the memory  18  stores the mode data indicative of a first pan and tilt mode with predetermined pan angle data and predetermined tilt angle data or a second pan and tilt mode with predetermined pan angle return position data and predetermined tilt angle return position data. 
     FIG. 3 depicts a flow chart of the second embodiment showing the operation of the microprocessor  14 . 
     The controller  17  generates and transmits the command in response to the operation keys  17   a  and the joystick  17   b.    
     The microprocessor  14  effects the operation shown in FIG. 3 in response to the command from the controller  17 . 
     At first, the microprocessor  14  checks whether there is the automatic pivoting set/reset (enable/disable) command from the controller  17  in step s 21 . If there is the automatic pivoting set/reset command from the controller  17  the microprocessor  14  stops the pan motor  8  and the tilt motor  5  in step s 22 . Then, if the automatic pivoting function has been reset, the microprocessor  14  sets the automatic pivoting function in step s 23 . If the automatic pivoting function has been set, the microprocessor  14  resets the automatic pivoting function in step s 23 . 
     In step s 21 , if there is not the automatic pivoting set/reset command from the controller  17 , the microprocessor  14  checks whether the tilting unit  33  and the panning unit  34  are at auto-pivoting start position in step s 24 , that is, whether panning and tilting directions of the camera unit  3  indicated by the operation commands from the controller  17  are toward the auto-pivoting start position, i.e., toward the door  31 . If the panning and tilting directions of the camera unit  3  indicated by the operation commands from the controller  17  are not toward the auto-pivoting start position in step s 24 , the microprocessor  24  controls pan and tilt motors  8  and  5  in accordance with the operation commands and the speed commands from the controller  17 . If the panning and tilting directions of the camera unit  3  indicated by the operation commands from the controller  17  is toward the auto-pivoting start position in step s 24 , the microprocessor  24  checks whether the tilt unit  33  and the panning unit  34  are at the auto-pivoting start position in step s 25 . 
     Regarding the auto-pivoting start position, the relation between the vertical angle of the camera unit  3  and the arm  21  has been adjusted to direct to the camera unit  3  to the door  31  as a tilt angle start position. The auto-pivoting start position of the pan angle is set by storing the pan angle start position in the memory  18  in response to the command from the controller  17 . 
     If the camera unit  3  is directed to the door  31  in step s 25 , the microprocessor  14  controls the pan motor  8  and the tilt motor  5  in step s 26 , the microprocessor  14  stops the tilt motor  5  and the pan motor  8  in step s 26 . Then, the microprocessor  14  checks whether setting the automatic pivoting function is maintained in step s 27 . If setting the automatic pivoting function is not maintained, processing returns to step s 21 . If setting the automatic pivoting function is maintained, the microprocessor  14  waits for 200 msec in step s 28 . 
     In the following step s 29 , the microprocessor  14  checks whether the tilt speed command and the pan speed command are successively inputted from just before the auto-pivoting start position. If the tilt speed command and the pan speed command are not successively inputted from just before the auto-pivoting start position, processing returns to step s 21 . If the tilt speed command and the pan speed command are successively inputted from just before the auto-pivoting start position, the microprocessor  14  stops (disable) the motion detection and alarm functions by the video signal processing circuit  15  in step s 30 . 
     In the following step s 31 , the microprocessor  14  operates the pan motor control circuit  13  to pan the camera unit  3  with observing the output of the horizontal position sensor  23  and the tilt motor control circuit  12  to tilt the camera unit  3  with observing the counts of the driving pulses for the tilt motor  5  and then stops the pan motor  8  and the tilt motor  5  when the camera unit  3  directs to the door  31 , i.e., the optical axis of the camera unit  3  returns to the pan angle return position and returns to the tilt angle return position (the door  32 ). Then, the microprocessor  14  waits for 100 msec in step s 32 . In this step, if the first pan and tilt mode is set in the memory  18 , the microprocessor  14  tilts and pans the camera unit  3  by the predetermined tilt angle data and the predetermined pan angle data. Moreover, if the second pan and tilt mode is set in the memory  18 , the microprocessor  14  tilts the camera unit  3  to the tilt angle position determined by the predetermined tilt angle return data and pans the camera unit  3  to the pan angle position determined by the predetermined pan angle return data. 
     In the following step s 33 , the microprocessor  14  operates (enables) the motion detection function and the alarm output functions of the video signal processing circuit  15 . Then, the microprocessor  14  checks whether the commands indicating stopping the pan motor  8  and the tilt motor  5  are inputted. If the commands indicating stopping the pan motor  8  and the tilt motor  5  are inputted by releasing the joystick  17   b,  processing returns to step s 21 . If the stop command indicating stopping the pan motor  8  and the tilt motor  5  are not inputted, processing waits the stop command and holds the tilt angle position and the pan angle position in step s 34  to prevent mistake operation. This is because the monitoring operator may holds the inclined angle of the joy stick  17   b  though the auto-pivoting operation has completed due to the high speed auto-pivoting operation. In that case, if the tilt unit  33  or the pan unit  34  immediately respond the joystick  17   b,  the monitoring operator may miss the image of the door  32 . Then, the tilt unit  33  and the pan unit  34  operates once a stop command is received after the auto-pivoting. That is, once the joystick  17   b  is released (at a rest position), the tilt unit  33  and the pan unit  34  start usual operation in step s 34 . The controller  17  sends the stop command to the microprocessor  14  when the inclined angle of the joystick  17   b  returns to zero. 
     In the auto-pivoting operation, the microprocessor  14  pans the video camera unit  3  at a maximum panning speed and at a maximum tilt speed. Moreover, in the second pan and tilt mode, the microprocessor  14  judges one of panning directions to provide a smaller panning angle and a shortest interval from the auto-pivoting start position of the pan angle position and the pan angle return position and tilt angle return position are stored in the memory  18 . In the auto-pivoting operation, the microprocessor  14  operates the panning unit  34  to pan the video camera unit  3  in the judged pan direction in step s 31 .