Camera system

Abstract

To stably supply a video even when power outage occurs in an environment where a camera is installed.SOLUTION: An entire control unit determines if an abnormality occurs in an environment of a camera (S2). The abnormality to be determined here is that a commercial AC power input to a first power supply unit is cut off (power outage). When recognizing that the abnormality occurs (S2: Yes), the entire control unit switches the power supply from the first power supply unit to a second power supply unit in the power supply unit (S3). Subsequently, the entire control unit switches an interface used in a communication unit from a wired communication interface part to a wireless LAN interface part (S4). The entire control unit sets a transmission destination of a video signal to a video storage server, and stores the video signal in the video storage server (S5). Subsequently, the entire control unit switches control performed by a camera body control unit to one under an abnormality mode (S6). Consequently, an imaging control unit sets high sensitivity of an image pick-up device so that the image pick-up device can cope with a case where illumination is set to be absent.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a camera system in which a video signal is transmitted via a network. [Background technology]

[0002] For example, in a disaster prevention camera system, images from a camera installed at a predetermined location are transmitted via a network to a server or terminal at a remote location. Furthermore, camera control (for example, control of the viewing direction) is also controlled from the server or terminal. In this case, continuous monitoring is required, so a camera system is used that automatically responds to any camera failures that may occur.

[0003] For example, Patent Document 1 describes a camera system that, when a power outage occurs on the camera side, switches its power source to an emergency power source and increases the frame rate of the recorded video, thereby improving surveillance capabilities, especially during power outages. Patent Document 2 also describes a camera system that, in a similar case, switches the camera's operation (for example, rotation operation) to a power-saving mode that consumes less power, thereby providing stable video even when using an emergency power source. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-182016 [Patent Document 2] Japanese Patent Application Publication No. 2018-088579 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0005] The technologies described in Patent Documents 1 and 2 specify operations to be performed in the event of a power outage. However, generally, it is not only the power supply to the camera that is cut off when a disaster occurs. For example, the lighting in the location where the camera is installed often also stops when a power outage occurs. In such cases, even with the above technologies, it is not possible to provide stable video. For this reason, even with the technologies described in Patent Documents 1 and 2, it is difficult to provide sufficiently stable video in the event of a power outage.

[0006] For this reason, there is a demand for a camera system that can provide stable video even in the event of a power outage in the environment where the camera is installed.

[0007] The present invention has been made in view of the above circumstances, and has as its object to solve the above problems. [Means for solving the problem]

[0008] The present invention is a camera system in which a camera installed at a predetermined location and an operating terminal that receives a video signal from the camera at a location separated from the camera are connected via a network, and the camera's power source can be switched between a first power supply unit that uses commercial AC power and a second power supply unit that uses a battery.When it is recognized that no power outage has occurred in the environment in which the camera is installed, the first power supply unit is used as the power source, and when it is recognized that a power outage has occurred in the environment in which the camera is installed, the second power supply unit is used as the power source.In addition, control is performed to increase the sensitivity of the camera and to lower the frame rate of the video signal compared to when no power outage has occurred in the environment in which the camera is installed. The camera is fixed to a pan head that controls the field of view of the camera, and when it is recognized that no power outage has occurred in the environment where the camera is installed, the pan head is driven in response to a control signal from the operation terminal, and when the pan head is not driven, a standby power that is smaller than the power required when the pan head is driven is supplied, and when it is recognized that a power outage has occurred in the environment where the camera is installed, the standby power when the pan head is not driven may be cut off. The network may be switchable between a first network which is a wired network and a second network which is a wireless network, and when it is recognized that no power outage has occurred in the environment where the camera is installed, the first network may be used as the network, and when it is recognized that a power outage has occurred in the environment where the camera is installed, the second network may be used as the network. The system may be provided with a video storage server that stores the video signal, and in a situation where it is recognized that no power outage has occurred in the environment where the camera is installed, the video signal may not be transmitted directly to the video storage server via the network, and in a situation where it is recognized that a power outage has occurred in the environment where the camera is installed, the video signal may be transmitted directly to the video storage server via the network. [Effects of the Invention]

[0009] According to the present invention, a camera system can be obtained that can stably supply video even if a power outage occurs in the environment where the camera is installed. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing a configuration of a camera system according to an embodiment; [Figure 2] 1 is a diagram showing a configuration of a camera in a camera system according to an embodiment; [Figure 3] 10 is a flowchart illustrating an example of an operation of the camera system according to the embodiment during a power outage. DETAILED DESCRIPTION OF THE INVENTION

[0011] Next, a camera system according to an embodiment of the present invention will be described in detail. FIG. 1 shows the overall configuration of this camera system 1. In this camera system 1, a camera body 10, which is an imaging device, and an illumination device 15 are combined with a pan head 20 that controls the field of view of the camera body 10 to form a camera 30, which is installed at a predetermined location. A video signal obtained from the camera body 10 is transmitted via a network to an operation terminal 50 and a video storage server 60, which are installed at a location remote from the camera 30. This video signal is displayed on the display of the operation terminal 50, allowing an administrator to view it. This video signal is also stored in the video storage server 60 as necessary. The illumination device 15 emits illumination light in the field of view of the camera body 10 to obtain high-quality images.

[0012] The pan head 20 controls the viewing direction (pan angle, tilt angle) of the camera body 10 together with the direction of the illumination light from the lighting device 15. This operation (control of the viewing direction of the camera body 10) is performed by an administrator operating the operation terminal 50, by transmitting a control signal issued from the operation terminal 50 to the pan head 20 side via the network.

[0013] In this camera system 1, two types of networks can be used to stably transmit video signals: a wired network (first network) N1 using optical communication, and a wireless LAN network (second network) N2 using wireless LAN. The two networks have different data transmission performances, and the wired network N1, which has better transmission performance, is normally used, while the wireless LAN network N2 is used when the wired network N1 becomes unavailable (in an emergency, etc.). In FIG. 1, only the base station 200 used in the wireless LAN network N2 is shown, but in reality, a mobile station is involved in communication between the base station 200 and the camera 30. In this way, since two networks are used, the operation terminal 50 and the video storage server 60 are connected to the wired network N1 and the LAN network N2 via a network switch (layer 2 switch) 70.

[0014] In this camera system 1, under normal circumstances (when it is recognized that no power outage has occurred in the environment where the camera 30 is located), communication between the camera 30 and the operation terminal 50 is performed via the wired network N1, as shown by the path R1 in Fig. 1. On the other hand, under emergency circumstances (when it is recognized that a power outage has occurred in the environment where the camera 30 is located), communication between the camera 30 and the operation terminal 50 is performed via the wireless LAN network N2, as shown by R2 in Fig. 1.

[0015] 2 is a block diagram showing the configuration of this camera 30. As described above, in this camera 30, the camera body 10, the lighting device 15 and the pan head 20 are combined together.

[0016] In FIG. 2, camera body 10 is provided with imaging unit 11, which uses an imaging element that captures an image and outputs an electrical signal, and video signal processing unit 12, which processes this electrical signal and outputs it as a video signal. Camera body control unit 13 is also provided to control the operation of camera body 10 during this process. For this control, camera body control unit 13 is provided with optical system control unit 131, which mechanically controls the optical system (lens, etc.) used here to control, for example, zoom, and imaging control unit 132, which controls the operation of the imaging element in imaging unit 11. Camera body control unit 13 performs these controls based on control signals (camera control signals) received from operation terminal 50. This control is performed from operation terminal 50 as necessary. Note that FIG. 2 shows a simplified depiction of only the minimum components related to the present invention; in reality, other components similar to those of a typical camera using an imaging element will be provided.

[0017] Here, items controlled by the imaging control unit 132 in the imaging unit 11 include its sensitivity, the frame rate of the image, etc. Sensitivity control is performed, for example, by setting the gain of an amplifier connected to the imaging element. During normal operation, this sensitivity is set to a constant value. Alternatively, this sensitivity is automatically set by the imaging control unit 132 so that an optimal image is obtained according to the obtained image (image signal).

[0018] The camera platform 20 is provided with a pan axis motor 21 that determines the pan angle and a tilt axis motor 22 that determines the tilt angle. The pan axis motor 21 and the tilt axis motor 22 can be, for example, stepping motors. The camera platform control unit 23 controls the pan axis motor 21 and the tilt axis motor 22 through operation from the operation terminal 50, thereby achieving a predetermined pan angle and tilt angle (field of view). This control of the camera platform 20 is performed by a control signal (camera platform control signal) received from the operation terminal 50. Note that FIG. 2 shows only the components of the camera platform 20 that electrically function in relation to this operation. Although various sensors and the like are actually provided to achieve these pan and tilt angles, these are not shown.

[0019] This camera 30 further includes components for controlling the entire combination of the camera body 10, lighting device 15, and camera platform 20, and is installed in a predetermined location with the components of FIG. 2 integrated. These components include a power supply unit 31 that supplies power to the entire camera 30. The power supply unit 31 is provided with a first power supply unit 31 having a power circuit that supplies power to the entire camera 30 under normal conditions. Commercial AC voltage is input to this power supply circuit, which is rectified and DC power for operating the camera body 10 and camera platform 20 is output from the first power supply unit. Meanwhile, the power supply unit 31 is also provided with a second power supply unit 312 that uses a storage battery. The second power supply unit 312 is used in place of the first power supply unit 311 in an emergency (power outage).

[0020] As described above, a wired network (first network) N1 and a wireless LAN network (second network) N2 are used for communication between the camera 30 and the operation terminal 50, etc. Therefore, the communication unit 32 for performing this communication is provided with a wired communication interface unit 321 for communication using the wired network N1 and a wireless LAN interface unit 322 for communication using the wireless LAN network N2.

[0021] An overall control unit 33 is provided to control the switching between the power supply unit 31 and the communication unit 32 (determine which one to use for each). The overall control unit 33 can recognize that a power outage has occurred, for example, when the commercial AC power input to the normal power supply circuit 311 is interrupted. In this case, the overall control unit 33 switches the output from the power supply unit 31 to that from the emergency power supply 312. This operation is similar to that in a well-known uninterruptible power supply (UPS), and allows the camera 30 to operate continuously. In addition to this operation, the overall control unit 33 also switches the interface used in the communication unit 32 to the wireless LAN interface 322.

[0022] As described above, in this camera system 1, during normal operation (normal mode), the operations of the camera body 10 and the camera platform 20 are controlled by control signals received from the operation terminal 50. In contrast, during an abnormality (abnormal mode) such as a power outage, the control of the power supply unit 31 and the communication unit 32 in the overall control unit 33 is carried out independently of this. Here, at this time, the overall control unit 33 controls the power supply unit 31 and the communication unit 32 to continue the supply of power to the camera 30, and can also continue communication (output of a video signal) by the communication unit 32.

[0023] In addition, the overall control unit 33 causes the camera body control unit 13 and the camera platform control unit 23 to operate in such a way that a stable video signal can be supplied even in such an abnormal state. In such an operation, the imaging conditions for the video signal are changed in consideration of the fact that the communication performance of the communication unit 32 may be deteriorated or unstable compared to normal operation. The overall control unit 33 also controls the lighting of the lighting device 15.

[0024] In particular, when a power outage occurs around the camera 30, it is often the case that not only the camera 30 but also the surrounding lighting (street lights, etc.) loses power. The imaging conditions are set taking such situations into consideration.

[0025] 3 is a flowchart showing the operation of camera 30. First, in the initial state (S1), camera system 1 is set to normal mode. In normal mode, as described above, in camera 30, first power supply unit 311 is selected for use in power supply unit 31, and wired communication interface unit 321 is selected for use in communication unit 32. Therefore, a video signal output from camera 30 is transmitted to operation terminal 50 via wired network N1. The video signal is stored in video accumulation server 60 by operating operation terminal 50 via operation terminal 50.

[0026] As described above, the camera body control unit 13 (optical system control unit 131, imaging control unit 132) is controlled by a camera control signal received from the operation terminal 50. However, the operation of the camera body 10 at this time is the operation when the camera 30 is in a normal environment. For this reason, for example, the sensitivity of the imaging element controlled by the imaging control unit 132 is set on the assumption that the camera body 10 is in an environment with a certain level of illumination. In this case, a low gain is set to reduce the effects of noise and obtain clear images. Furthermore, the frame rate of the image is set to, for example, about 5 fps, which is suitable for monitoring. The image signal obtained under these conditions is transmitted to the operation terminal 50.

[0027] Furthermore, in the camera 30, the lighting device 15 is used in normal mode to obtain particularly good images. At this time, the overall control unit 33 turns on the lighting device 15 in accordance with, for example, the environmental illuminance detected by an illuminance sensor (not shown in FIG. 2 ) or the time of day. The operation of the camera head 20 is controlled by the camera head control signal as described above. To ensure this operation is accurate and fast, a small holding current flows through the pan axis motor 21, tilt axis motor 22, etc., even when the camera head is not operating. Therefore, in normal mode, even when the camera head 20 is not actually controlling the direction of view (the pan axis motor 21 and tilt axis motor 22 are not operating), power based on this holding current is consumed as standby power for the camera head 20. However, this power is significantly smaller than the power consumed when the camera head is controlling the direction of view (the pan axis motor 21 and tilt axis motor 22 are operating). The lighting device 15 also consumes power.

[0028] Next, the overall control unit 33 determines whether an abnormality has occurred in the environment of the camera 30 (S2). The abnormality determined here is that the commercial AC power input to the first power supply unit 311 has been cut off (power outage). If it is determined that no abnormality has occurred (S2: No), the above-described normal mode operation is maintained.

[0029] If an abnormality is recognized (S2: Yes), the following operation in abnormal mode is performed. First, the overall control unit 33 switches the power supply in the power supply unit 31 from the first power supply unit 311 to the second power supply unit 312 (S3). This makes it possible to operate the camera 30 even during a power outage. This operation is similar to that of a normal UPS power supply, etc., and this switching is performed without interrupting the power supply.

[0030] Next, the overall control unit 33 switches the interface used by the communication unit 32 from the wired communication interface unit 321 to the wireless LAN interface 32 (S4). Generally, the wireless LAN network N2 is less susceptible to the effects of a power outage than the wired network N1, so this allows for stable transmission of video signals even after a power outage.

[0031] Furthermore, the overall control unit 33 sets the destination of the video signal to the video storage server 60, and stores this video signal in the video storage server 60 (S5). As described above, in the normal mode, the destination of the video signal is the operation terminal 50, but the setting may also be such that the video signal continues to be transmitted to the operation terminal 50.

[0032] Next, the overall control unit 33 switches the control by the camera body control unit 13 to that under abnormal mode (S6). As a result, the imaging control unit 132 sets the sensitivity (gain) of the imaging element to a high value, regardless of the camera control signal, so as to correspond to the case where the environment in which the camera body 10 captures images is set to have no illumination. As described above, while this increases noise, it is possible to obtain a stable image of the imaging target even when there is no illumination.

[0033] Furthermore, the imaging control unit 132 reduces the frame rate of the imaging element to, for example, 1 fps or less (or outputs a still image). This reduces the data capacity of the output video signal, enabling more reliable transmission. It also reduces the power consumption of the camera body 10, extending the time that the camera can operate on the emergency power supply 31B (battery). While increasing the sensitivity as described above increases noise, for example, by lengthening the time (exposure time) required to acquire a single image, the effects of noise can be reduced, and a clearer image can be obtained, particularly for a stationary subject. In other words, this operation of increasing sensitivity is particularly effective when performed simultaneously with reducing the frame rate as described above.

[0034] Next, the overall control unit 33 also switches the control by the camera head control unit 23 to that in the abnormal mode (S7). As a result, the camera head control unit 33 cuts off the holding current, that is, cuts off the standby power in the camera head 20. This makes it impossible to operate the camera head 20 accurately and quickly, but it reduces the power consumption in the camera head 20 and enables the camera 30 to operate for a longer period of time using the emergency power supply 31B (battery).

[0035] In addition, the overall control unit 33 turns off the illumination device 15 (S8). As described above, in the normal mode the lighting state of the illumination device 15 is controlled by the illuminance, the time of day, etc., but here, the illumination device 15 is turned off regardless of these. As described above, in this case, it is desirable to turn on the illumination device 15 from the viewpoint that there is no external lighting. However, since the power consumption of the illumination device 15 is relatively large, from the viewpoint of extending the time that the device can operate on the emergency power supply 31B (battery), it is preferable to turn off the illumination device 15 and instead perform imaging by changing the imaging conditions of the camera body 10 to night vision as described above.

[0036] Although a flowchart is shown in FIG. 3, in reality, only the power supply switching (S3) may be performed first, and the other steps (S4 to S8) may be performed immediately thereafter and simultaneously.

[0037] The abnormal mode setting of the camera body 10 and the camera platform 20 as described above can be set to be cancelled, for example, when the overall control unit 33 receives a command from the operation terminal 50. Alternatively, the setting may be such that the camera body 10 and the camera platform 20 return from the abnormal mode to the normal mode (S1) when the overall control unit 33 recognizes that the input of commercial AC power has resumed.

[0038] By the above operation, even if a power outage occurs in the environment where the camera 30 is installed, the video signal can be stably supplied from the camera 30. At this time, since such a situation occurs suddenly, there may be cases where the administrator is not present near the operation terminal 50, but the video signal in the emergency mode is stored in the video storage server 60 (S5), so the administrator can check the video later.

[0039] In the above example, the wireless LAN network N2 is used instead of the wired network N1 in emergency mode (S4). However, if the wired network N1 is usable even during a power outage, the wired network N1 may continue to be used during a power outage. However, even in this case, communication using the wired network N1 is often unstable. Therefore, reducing the data capacity of the transmitted video signal as described above is effective in this case as well, allowing the video storage server 60 (or the operation terminal 50) to stably obtain the video signal. Also, from the viewpoint of line usage fees (cost efficiency), it is preferable to use the wired network N1 preferentially.

[0040] Furthermore, the operation of setting the standby power of the camera platform 20 to zero in emergency mode as described above (S7) does not need to be performed if the standby power is small. Alternatively, the lighting device 15 may be turned off (S8) only, while maintaining the motor's holding current. In other words, the standby power of the camera platform 20 may not be set to zero, and the overall power consumption on the camera platform 30 side may be reduced. The content of this operation is set appropriately depending on the configuration of the camera platform 20, etc.

[0041] The present invention has been described above based on an embodiment. This embodiment is merely an example, and it will be understood by those skilled in the art that various modifications are possible in the combination of the respective components, and that such modifications are also within the scope of the present invention. [Explanation of symbols]

[0042] 1 camera system 10 Camera body 11 Imaging unit 12 Video signal processing section 13 Camera body control unit 15 Lighting equipment 20 Pan head 21 Pan axis motor 22 Tilt axis motor 23 Head control unit 30 Camera 31 Power supply section 32 Communications Department 33 Overall control unit 50 Operation terminal 60 Video storage server 70 Network Switch (Layer 2 Switch) 131 Optical system control unit 132 Imaging control unit 200 base stations 311 1st power supply section 312 2nd power supply section 321 Wired communication interface unit 322 Wireless LAN interface section N1 Wired network (first network) N2 Wireless LAN network (second network)

Claims

1. A camera system in which a camera installed at a predetermined location and an operation terminal that receives a video signal from the camera at a location remote from the camera are connected via a network, The camera is configured so that a first power supply unit using a commercial AC power supply and a second power supply unit using a battery can be switched between them as a power source; When it is recognized that no power outage has occurred in the environment where the camera is installed, the first power supply unit is used as the power supply, In a situation where a power outage is recognized in the environment where the camera is installed, The second power supply unit is used as the power supply, The camera system is characterized in that it controls the sensitivity of the camera to be higher than in a situation where no power outage occurs in the environment in which the camera is installed, and controls the frame rate of the video signal to be lower.

2. The camera is fixed to a pan head that controls the viewing direction of the camera; When it is recognized that no power outage has occurred in the environment where the camera is installed, the pan head is driven in response to a control signal from the operation terminal, and when the pan head is not driven, standby power smaller than the power required for driving the pan head is supplied; The camera system according to claim 1, wherein when a power outage is recognized in an environment where the camera is installed, the standby power is cut off when the camera is not being driven.

3. The network can be switched between a first network, which is a wired network, and a second network, which is a wireless network; When it is recognized that no power outage has occurred in the environment where the camera is installed, the first network is used as the network; 3. The camera system according to claim 1, wherein the second network is used as the network when it is recognized that a power outage has occurred in an environment in which the camera is installed.

4. a video storage server that stores the video signal; When it is recognized that no power outage has occurred in the environment where the camera is installed, the video signal is not directly transmitted to the video storage server via the network, The camera system described in claim 1 or 2, characterized in that when a power outage is recognized to have occurred in the environment in which the camera is installed, the video signal is transmitted directly to the video storage server via the network.

Images