JP2007013278A - Battery-driven network camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery-driven network camera capable of extending a camera operating time by lending a longer lifetime to the battery for any length of time. <P>SOLUTION: The battery-driven network camera 10 includes: an image input means 12 for photographing a moving picture; a panning drive means 14 for revolving the image input means 12 in a horizontal direction; a tilt drive means 16 for revolving the image input means 12 in a vertical direction; a wireless communication means 26 for making communication with an external terminal 24 connected to a network by means of wireless communication; a system control means 32 for controlling the means above; the battery 28 for supplying power to each means; and a battery capacity detection means 30 for detecting the capacity of the battery 28, and when the battery capacity detection means 30 detects that the capacity of the battery 28 is less than a prescribed setting value, the system control means 32 controls the camera to be shifted to a prescribed power-saving mode so as to suppress the consumption of the battery 28. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a battery-powered network camera.

  For wireless network cameras, such as surveillance cameras and video conferencing systems, when viewing and controlling captured images and camera control with an external terminal, supply power if the camera is powered from an AC outlet There is no worry about time, but it is limited by the installation location.

  On the other hand, if it is a type in which power is supplied to the camera by a battery, the place of use and the use are expanded without being restricted by the location of the AC outlet. However, in this case, since functions such as pan, tilt, and wireless included in the camera have a large load current, it is desired to save power so that the operation time of the battery becomes as long as possible.

Patent Document 1 below discloses a communication terminal device that can reduce power consumption as a whole device by supplying power only to necessary functional blocks according to the operating state. However, the device of Patent Document 1 does not assume battery driving, and does not describe a control change when the battery capacity decreases.
JP-A-7-212736

  Therefore, an object of the present invention is to provide a battery-driven network camera that can extend the camera operating time by holding the battery as long as possible.

In order to solve the above-mentioned problems, a battery-driven network camera according to the present invention includes an image input unit that captures a moving image, a pan driving unit that rotates the image input unit in the left-right direction, and the image input unit that moves up and down. Tilt driving means for rotating the apparatus, wireless communication means for communicating with an external terminal connected to the network via wireless, system control means for controlling the means, and a battery for supplying power to the means, Battery capacity detecting means for detecting the capacity of the battery,
When it is detected by the battery capacity detection means that the capacity of the battery falls below a predetermined set value, the system control means performs control to shift to a predetermined power saving mode so as to suppress the consumption of the battery. It is characterized by this.

  In the battery-driven network camera according to the present invention, when the battery capacity detection unit detects that the capacity of the battery is lower than a first set value, the system control unit includes the pan driving unit and the tilt driving unit. During driving, control for shifting to the first power saving mode in which transmission of moving images from the wireless communication means is stopped may be performed. In this case, in the first power saving mode, the pan driving unit and the tilt driving unit may not be driven simultaneously.

  Further, in the battery-driven network camera of the present invention, when the battery capacity detection unit detects that the capacity of the battery falls below a second set value lower than the first set value, the system control unit The driving speed of the pan driving means and the tilt driving means is decreased, and the driving to the second power saving mode in which the transmission of the moving image from the wireless communication means is stopped while the pan driving means and the tilt driving means are being driven. Control may be performed. In this case, in the second power saving mode, the wireless output of the wireless communication means may be reduced.

  In the battery-powered network camera of the present invention, the pan driving unit and the tilt driving unit cannot be driven, the driving unit is driven slowly, the wireless output is reduced or zero, and the image quality of the moving image is reduced. And reducing the frame rate of the moving image may be executed alone or in combination as the power saving mode.

  The battery-powered network camera of the present invention may further include a power saving mode notification means for notifying that the camera is operating in the power saving mode.

  According to the battery-driven network camera of the present invention, when the battery capacity is reduced, the battery shifts to the power saving mode such as not transmitting a moving image during pan-tilt driving so as to suppress battery consumption. The camera operation time can be extended by keeping the camera as long as possible.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a block diagram of a battery-powered network camera (hereinafter simply referred to as “camera” as appropriate) 10 according to a first embodiment of the present invention.

  The camera 10 includes an image input unit 12 that captures a moving image, a pan motor drive unit 14 that rotates the image input unit 12 left and right, for example, and a step that rotates the image input unit 12 up and down. Wireless communication via a motor-driven tilt drive means 16, memory means 18 for storing captured image data, program data, communication data, etc., an external terminal 24 connected to the network 22, and an access point 20 outside the camera 10 The wireless communication means 26 for performing the above operation, the battery 28 for supplying power to the respective means, the battery capacity detecting means 30 for detecting the capacity of the battery 28, and the means 12, 14, 16, 18, 26, 28, 30. And system control means 32 for performing control.

  The image input means 12 is composed of, for example, an image sensor such as a CCD sensor and an optical system including a lens, and has an image capturing function. As the battery 28, for example, a lithium ion battery is preferably used. Further, the wireless communication unit 26 includes an output unit that transmits a moving image stream and an input unit that receives a command from the external terminal 24.

Next, the operation of the camera 10 having the above configuration will be described.
FIG. 2 shows an operation sequence when the capacity of the battery 28 is still sufficient. When the camera 10 receives a pan / tilt command from the external terminal 24 via the wireless communication unit 26, the pan driving unit 14 and the tilt driving unit 16 are simultaneously driven. Even during the pan-tilt operation, the output unit of the wireless communication means 26 is used except for transmitting an “answer” signal for the “confirmation” signal for confirming whether the camera 10 is in a position where it can communicate with the access point 20. A video stream is transmitted from. In this case, the image during the pan / tilt operation is transferred, and a more realistic image can be confirmed on the external terminal 24.

  Due to the operation of the camera 10, the capacity of the battery 28 gradually decreases. When the battery capacity detection unit 30 detects that the capacity of the battery 28 has fallen below a first set value (for example, 20%), the system control unit 32 performs control to shift to the first power saving mode. In the first power saving mode, as shown in FIG. 3, during the driving of the pan driving means 14 and the tilt driving means 16, the power supply to the output unit of the wireless communication means 26 is stopped to stop the moving image transmission. In this case, the sense of reality is sacrificed to some extent, but since the electrical load per unit time is suppressed, the consumption of the battery 28 can be suppressed and the operation time of the camera 10 can be lengthened.

  In the first power saving mode, as shown in FIG. 4 (upper diagram), when the pan / tilt is driven simultaneously, the overshoot 42 and the undershoot 44 at the time of on / off increase. Therefore, as shown in FIG. The drive unit 14 and the tilt drive unit 16 may be driven individually with a time shift instead of simultaneously. In this way, although it takes time to complete the pan / tilt operation, the load current fluctuation range including the overshoot 42 and the undershoot 44 at the time of on / off can be suppressed, so that rapid consumption of the battery 28 can be suppressed. Further, while the video transmission from the wireless communication unit 26 is stopped, the power supply to the image input unit 12 may also be stopped to suppress the consumption of the battery 28.

  When the battery capacity detection unit 30 detects that the capacity of the battery 28 has further decreased and has fallen below a second set value (for example, 10%), the system control unit 32 performs control to shift to the second power saving mode. Do. In the second power saving mode, as shown in FIG. 5, the driving speeds of the pan driving means 14 and the tilt driving means 16 are slowed down, and during the driving of the pan driving means 14 and the tilt driving means 16 from the wireless communication means. Stop sending video. In this case, as shown in FIG. 6, in the second power saving mode shown in the lower diagram, the driving time of the pan driving means 14 and the tilt driving means 16 is longer than in the first power saving mode shown in the upper diagram, but the overtime at the on / off time is increased. By suppressing the load current fluctuation range including the chute 42 and the undershoot 44, rapid consumption of the battery 28 can be further suppressed.

  In the second power saving mode, the output power of the wireless communication means 26 may be reduced by 20%, for example. As a result, as shown in FIG. 7, as compared with the first power saving mode in the upper diagram, the load current fluctuation range including the overshoot 42 and the undershoot 44 at the on / off time can be suppressed in the second power saving mode in the lower diagram. Thus, there is an effect that the consumption of the battery 28 can be further suppressed.

Next, a battery-driven network camera 50 according to a second embodiment of the present invention will be described with reference to FIG.
The camera 50 of the present embodiment further includes a power saving mode notification unit 52 connected to the system control unit 32 in addition to the configuration of the camera 10 of the embodiment. The power saving mode notification means 52 can be constituted by a light emitting diode that is visible from the outside, for example, in the camera 50, and displays the power saving mode display on the display unit of the external terminal 24 by transmitting via the wireless communication means 26. Can be made. Since the other configuration and the power saving mode operation are the same as those of the camera 10, the same components are denoted by the same reference numerals and description thereof is omitted.

  In the camera 50 of the present embodiment, the user is notified that the operation is being performed in the first power saving mode by the light emission of the light emitting diode or the display on the external terminal 24. As a result, the user can know that the capacity of the battery 28 has decreased and is operating in the power saving mode, and can confirm that the remaining usable time is short or that the battery needs to be replaced. it can.

By the way, the present invention is not limited to the above-described embodiment, and various other modifications are possible.
For example, the pan driving unit 14 and the tilt driving unit 16 cannot be driven, the driving of the pan driving unit 14 and the tilt driving unit 16 is slow, the wireless output of the wireless communication unit 26 is reduced or zero, and the image quality of the moving image is improved. Executing at least one of reducing and reducing the frame rate of the moving image (for example, typically 30 frames / second) alone or in combination with the first power saving mode or the second power saving mode. Also good.

The block diagram of the battery drive type network camera of 1st Embodiment. The operation | movement sequence diagram when there is enough battery capacity. The operation | movement sequence diagram of a 1st power saving mode. The figure which shows the load current when pan / tilt is driven simultaneously or separately. The operation | movement sequence diagram of a 2nd power saving mode. The figure which shows the load current at the time of pan | tilt drive in 1st power saving mode and 2nd power saving mode. The figure which shows the change of load current when a radio | wireless output is reduced in 2nd power saving mode with respect to 1st power saving mode. The block diagram of the battery drive type network camera of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 50 ... Battery drive type network camera 12 ... Image input means 14 ... Pan drive means 16 ... Tilt drive means 18 ... Memory means 20 ... Access point 22 ... Network 24 ... External terminal 26 ... Wireless communication means 28 ... Battery 30 ... Battery Capacity detection means 52 ... Power saving mode notification means

Claims (7)

Image input means for capturing a moving image, pan driving means for rotating the image input means in the horizontal direction, tilt driving means for rotating the image input means in the vertical direction, and an external terminal connected to the network and wireless Wireless communication means for communicating via, system control means for controlling each means, a battery for supplying power to each means, and battery capacity detection means for detecting the capacity of the battery,
When it is detected by the battery capacity detection means that the capacity of the battery falls below a predetermined set value, the system control means performs control to shift to a predetermined power saving mode so as to suppress the consumption of the battery. A battery-powered network camera.   When it is detected by the battery capacity detection means that the capacity of the battery has fallen below the first set value, the system control means receives from the wireless communication means during the driving of the pan driving means and the tilt driving means. The battery-driven network camera according to claim 1, wherein control for shifting to a first power saving mode for stopping transmission of moving images is performed.   3. The battery-driven network camera according to claim 2, wherein in the first power saving mode, the pan driving unit and the tilt driving unit are not driven simultaneously.   When it is detected by the battery capacity detection means that the capacity of the battery falls below a second set value that is lower than the first set value, the system control means drives the pan drive means and the tilt drive means. The control for shifting to the second power saving mode for stopping transmission of moving images from the wireless communication unit is performed while the speed is decreased and the pan driving unit and the tilt driving unit are driven. The battery-powered network camera described.   The battery-powered network camera according to claim 4, wherein in the second power saving mode, the wireless output of the wireless communication unit is reduced.   Disabling the pan driving means and the tilt driving means, slowing the driving of the driving means, reducing or reducing the wireless output, reducing the image quality of the moving image, and reducing the frame rate of the moving image; The battery-powered network camera according to claim 1, wherein at least one of the power saving modes is executed alone or in combination as the power saving mode.   The battery-powered network camera according to any one of claims 1 to 6, further comprising power saving mode notification means for notifying that the power saving mode is operating.

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