JP4136544B2 - Image backup system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image backup technique in an image distribution system for distributing an image at a remote place via a network.
[0002]
[Prior art]
There are so-called Web cameras and video servers that distribute images via a network. Some Web cameras and moving image servers include a recording area composed of a hard disk or a semiconductor memory that digitally records images and sounds on the main device. These are sometimes called stored moving image servers.
[0003]
In a viewing station connected to the stored moving image server via a network, it is possible to view an image taken by the stored moving image server in real time. The viewing station can also browse images stored in the stored moving image server at an arbitrary timing via the network.
[0004]
Furthermore, there is a system in which a base station is added to an image distribution system including a stored moving image server and a viewing station. In this system, data is exchanged via a base station, and various processes such as authentication, billing, data conversion, and data recording are performed in the base station. And in this system form, the image distributed by the stored moving image server is relayed and transmitted to other viewing stations via the base station.
[0005]
[Problems to be solved by the invention]
The above-described stored moving image server is used for a system for crime prevention (security) and monitoring (monitoring), for example. When used for such purposes, the image data stored in the stored moving image server is very important information.
[0006]
However, equipment may fail and sometimes valuable recorded data may be lost. Because the stored video server is distributed in various places due to its characteristics, it is difficult to perform maintenance and data backup for all devices.
[0007]
Furthermore, if the number of stored moving image servers distributed in various places increases, it is difficult to manage all image data at a base station or the like. When backup is performed at the base station in a lump, the hard disk capacity of the base station becomes enormous, and when a failure occurs in this hard disk, all the stored moving image server data is lost.
[0008]
Therefore, in view of the above problems, the present invention provides a system that can protect image data without increasing the burden of maintenance while avoiding the problem of centralized management of backup data. With the goal.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention focuses on the fact that the video server is connected to the network, and prevents data loss by backing up data over the network before a failure such as a failure occurs. I will do it.
[0011]
Claim 1 According to the invention, in an image distribution system including first and second image storage devices and a base station, the system backs up images, wherein the first and second image storage devices include photographing means, Storage means for accumulating images acquired by the photographing means, and means for distributing the images accumulated in the storage means to the image browsing terminal in response to a request from an image browsing terminal connected via a network. The first image storage device further includes means for acquiring state information of the device itself, and means for transmitting the state information to the base station, wherein the base station receives the received state information. When judging based on a predetermined condition indicating the possibility of failure and judging the state of the first image storage device and the first image storage device is likely to fail Includes an instruction unit that transmits a duplication instruction to the first image storage device, and the first image storage device further stores the copy unit when receiving the duplication instruction. Means for transmitting a copy of the image to be transmitted to the second image storage device via a network, wherein the second image storage device further stores the received copy in the storage means of the device itself, It is characterized by providing.
[0012]
Claim 2 In the invention of claim 1 In the image backup system according to claim 1, the image distribution system includes a plurality of image storage devices including the first and second image storage devices, and the determination unit receives the state from each image storage device. Means for specifying an image storage device in a normal state as information from the information as the second image storage device, wherein the instruction means images the image storage device in a normal state specified as the second image storage device. Means for instructing as a backup device.
[0013]
Claim 3 In the invention of claim 1 Or claims 2 In the image backup system according to claim 1, the instruction means includes means for instructing the base station as an image backup apparatus instead of the second image storage apparatus, and the first image storage apparatus further includes: And a means for transmitting a copy of the image stored in the storage means of the own apparatus to the base station via a network when the base station is instructed as an apparatus for image backup.
[0014]
Claim 4 In the invention of claim 1 Or claims 3 In the image backup system according to any one of the above, the instruction means includes means for instructing the image browsing terminal as an image backup device instead of the second image storage device, and the first image storage device Further includes means for transmitting a copy of the image stored in the storage means of the own device to the image browsing terminal via a network when the image browsing terminal is designated as an image backup device. And
[0015]
Claim 5 In the invention of claim 1 Or claims 4 In the image backup system according to any one of the above, when the base station further transmits the duplication instruction, it notifies the administrator who manages the first image storage device by e-mail. Means for performing.
[0016]
Claim 6 In this invention, the system backs up an image between the first and second image storage devices, wherein the first and second image storage devices store the photographing means and the image acquired by the photographing means. Storage means, a means for receiving a request from an image browsing terminal connected via a network, distributing the image stored in the storage means to the image browsing terminal, and a timing means for outputting a current time. When the current time acquired from the time measuring means is a predetermined first time zone, the second image storage is performed via the network by copying the image stored in the storage means of the first image storage device. When backup is performed by transmitting to the apparatus and the current time acquired from the time measuring means is within a predetermined second time zone, a copy of the image stored in the storage means of the second image storage apparatus is stored. The and performing backup by transmitting the first image storage apparatus via a network.
[0017]
Claim 7 The invention of claim 6 In the image backup system according to claim 1, the first time zone is a main operating time zone of the first image storage device, and the second time zone is a main operating time of the second image storage device. It is a belt.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0019]
{Embodiment 1}
The first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a functional configuration related to image distribution of the stored moving image server 1. The stored moving image server 1 includes an imaging unit 11, a microphone 12, an image / audio processing unit 13, an image storage unit 14, and an information distribution unit 15.
[0020]
The imaging unit 11 includes an optical system member, a CCD, and the like, and can capture an image of a subject. The image / sound processor 13 performs an encoding process on the image and sound data input from the imaging unit 11 and the microphone 12. The image storage unit 14 stores image and sound data output from the image / sound processing unit 13. The information distribution unit 15 distributes the image and sound data output from the image / sound processing unit 13 to the network in real time. The information distribution unit 15 can distribute the image and audio data stored in the image storage unit 14 to the network.
[0021]
The stored moving image server 1 has the above functions, and can be distributed in real time to the viewing station 3 (shown in FIG. 2) via the network by being installed in the vicinity of the subject. In addition, by receiving a distribution request from the viewing station 3 at an arbitrary timing, the subject image stored in the image storage unit 14 can be distributed to the browsing station 3. The distributed subject image may be a moving image or a still image.
[0022]
FIG. 2 is an overall view of the image distribution system. In the image distribution system, each of the stored moving image servers 1A, 1B, and 1C having the functions shown in FIG. 1 is installed in various places according to the purpose (the stored moving image servers 1A, 1B, and 1C are appropriately stored videos). Collectively referred to as server 1). The stored moving image servers 1A, 1B, and 1C are connected via a network. The network includes, for example, the Internet, a dedicated line, a telephone line, and the like, and the stored moving image servers 1A, 1B, and 1C can communicate with each other using a protocol such as TCP / IP.
[0023]
In the present invention, each of the stored moving image servers 1A, 1B, 1C protects the image data by mutually backing up the image data stored between the respective devices. It is.
[0024]
That is, each of the stored moving image servers 1A, 1B, and 1C stores the image data captured by the device itself in the image storage unit 14 of the device. Each of the stored moving image servers 1A, 1B, 1C generates a copy of the image data stored in the image storage unit 14 by the information distribution unit 15 and transmits the generated copy data to the other stored moving image server 1. is there.
[0025]
On the other hand, the stored moving image server 1 that has received the replicated data from the other stored moving image server 1 stores the received replicated data of the image in the image storage unit 14 of its own device.
[0026]
In this way, in each of the stored moving image servers 1A, 1B, 1C, in addition to the image data photographed by the own device, the other stored moving image servers 1A, 1B, 1C, connected via the network. 1C image data is also stored.
[0027]
For example, if the image distribution system is composed of two stored moving image servers 1A and 1B, a copy of the image taken by the stored moving image server 1A is transmitted to the stored moving image server 1B, and the image stored in the stored moving image server 1B is stored. A backup is taken in the unit 14. Conversely, a copy of the image taken by the stored moving image server 1B may be transmitted to the stored moving image server 1A, and the image storage unit 14 of the stored moving image server 1A may take a backup.
[0028]
Further, if the image distribution system is composed of three stored moving image servers 1A, 1B, and 1C, a copy of the image taken by the stored moving image server 1A is transmitted to the stored moving image server 1B, and the stored moving image server 1B A backup is taken in the image storage unit 14, a copy of the image taken by the stored video server 1B is transmitted to the stored video server 1C, and a backup is taken in the image storage unit 14 of the stored video server 1C. The copied image may be transmitted to the stored moving image server 1A, and the image storage unit 14 of the stored moving image server 1A may take a backup. Even when there are more stored moving image servers, by chaining the transfer in the same way, each stored moving image server 1 can store one other stored moving image in addition to the image data captured by its own device. The server 1 can be configured to store replicated data.
[0029]
The two backup procedures (combinations) described above are forms in which one stored moving image server 1 stores, as a backup, copy data of another one stored moving image server 1 in addition to the image data captured by the own device. Of course, one stored moving image server 1 may store duplicate data of a plurality of other stored moving image servers 1. For example, if a specific stored moving image server 1 includes a hard disk having a relatively large capacity, a configuration may be adopted in which replicated data of several other stored moving image servers 1 are stored. However, from the viewpoint of risk distribution, it is preferable to distribute the backup destinations rather than concentrating data backups of a large number of devices on one stored moving image server 1.
[0030]
By performing such a backup process, it is possible to avoid the loss of image data even if any server fails. In addition, since a separate apparatus such as a data backup server is not required and the existing moving image storage server functions as a backup apparatus, a backup system can be prepared at low cost.
[0031]
Furthermore, since the base station or the like is different from the mechanism for batch backup of the image data of all the stored moving image servers 1, even if a failure occurs in the backup stored moving image server 1, the range in which the influence is exerted And the reliability of the entire system can be improved.
[0032]
{Embodiment 2}
<Functions of each device>
Next, Embodiment 2 of the present invention will be described with reference to FIG. Also in the second embodiment, the stored moving image servers 1D, 1E, and 1F have the functions of the stored moving image server 1 shown in FIG. 1, and can store and distribute images (stored moving image servers 1D, 1E). , 1F are also collectively referred to as the stored moving image server 1 as appropriate.) In the second embodiment, the stored moving image servers 1D, 1E, and 1F include a self-diagnosis unit 17 and a replication processing unit 18 as shown in FIG. 3 in addition to the functions shown in FIG. In the figure, only the stored moving image server 1D shows functional blocks, but the stored moving image servers 1E and 1F also have similar functions.
[0033]
The self-diagnosis unit 17 is a functional unit that the accumulated moving image server 1 acquires state information for diagnosing the operation state of the own device. Furthermore, the self-diagnosis unit 17 has a function of transmitting state information as a diagnosis result to the base station 3 via the network.
[0034]
In response to an instruction from the base station 3, the duplication processing unit 18 generates duplication data of the image accumulated in the image accumulation unit 14, and functions to instruct the information distribution unit 15 to transmit duplication data. It is. Further, the replication processing unit 18 notifies the information distribution unit 15 of the backup destination information of the replicated data designated by the base station 3.
[0035]
On the other hand, the base station 3 includes a storage unit 31, a failure machine diagnosis unit 32, a destination determination unit 33, and a duplication instruction unit 34.
[0036]
The storage unit 31 is a functional unit that stores duplicate data of images stored in the image storage unit 14 of the stored moving image server 1. The trouble machine diagnosis unit 32 is a functional unit that aggregates the state information acquired by the self-diagnosis unit 17 of each stored video server 1 and diagnoses the possibility of failure of each stored video server 1. The destination determination unit 33 is a functional unit that determines a device that backs up an image of the stored moving image server 1 that has a possibility of failure. The duplication instruction unit 34 is a functional unit that sends an instruction to send duplication data to the stored moving image server 1 having a possibility of failure. Further, the replication instruction unit 34 has a function of notifying the backup destination information determined by the destination determination unit 33 as the transmission destination of the replication data when transmitting the replication instruction.
[0037]
The browsing station 5 is normally a terminal station that browses the images stored in each of the stored video servers 1D, 1E, and 1F by transmitting an image distribution request to each of the stored video servers 1D, 1E, and 1F. Furthermore, in the second embodiment, the browsing station 5 includes a storage unit 51 and is used as a backup device for images stored in the image storage unit 14 of the stored moving image server 1.
[0038]
<Example of self-diagnosis>
As described above, the failure machine diagnosis unit 32 of the base station 3 diagnoses the operating state of each stored moving image server 1. The target of diagnosis is not particularly limited, but as one criterion, it is necessary to be a target that can be quantitatively grasped. This is because the possibility of failure can be objectively determined by diagnosing the state of the apparatus that can be quantitatively grasped. Further, as another criterion, it is necessary to be a target from which a failure or a possibility of failure can be determined. That is, the state of a certain target is acquired quantitatively and compared with a predetermined condition (reference). If the result of the comparison judgment shows that there is a possibility of failure when the condition falls below a predetermined condition, or if it can be judged that the performance of the device is deteriorated and normal service cannot be maintained, data backup is taken. This is because a necessity arises.
[0039]
As an example of a target to be diagnosed, for example, a method of checking the discharge amount by which the information distribution unit 15 of the stored moving image server 1 transmits an image or recording data can be considered. As a means for quantitatively grasping the discharge amount, the FPS value (= number of frames) and the BPS value (= bandwidth) of the data amount distributed by the information distribution unit 15 are measured, and these values are larger than predetermined values. It is possible to predict a failure when it falls off and becomes smaller. By performing this diagnosis, it is possible to predict mainly communication devices, communication programs, image distribution programs, and other hardware failures.
[0040]
Other examples of performing diagnosis include the time for each stored video server 1 to access other terminals via the network, and response times such as sensing (= access sensing), pin (Ping), and trace (trace) commands. A method of measuring FTP transfer time, etc. can be considered. It is possible to predict a failure when these responses, measurement time, etc. are greater than normal values. By performing this diagnosis, it is possible to predict mainly communication devices, communication programs, image distribution programs, and other hardware failures.
[0041]
As another example of performing the diagnosis, a method of checking the data amount of the image input by the image sound processing unit 13 or the image storage unit 14 of each stored moving image server 1 can be considered. It is possible to predict a failure when the data amount of the input image is zero or extremely small. By performing this diagnosis, it is possible to predict mainly a failure in an imaging system such as an optical system or a CCD, a failure in an image processing device or an image processing program, and the like.
[0042]
In addition, failure prediction can be performed based on the results of malfunction of buttons and SW of each stored video server 1, voltage drop of the built-in battery, extreme increase in the operating rate of the CPU, and the like. Furthermore, failure prediction can be performed by checking for defects or responses of externally connected devices such as sensors.
[0043]
Further, as a failure diagnosis, it is possible to check the free space of the hard disk of each stored video server 1. The available capacity of the hard disk constituting the image storage unit 14 is checked, and if the available capacity is reduced, the possibility of failure can be determined in advance. Note that the lack of free hard disk space is generally not a failure of the device, but the lack of free hard disk space can lead to failure such as the operation of the stored video server 1 becoming unstable. Therefore, it can be a diagnosis target.
[0044]
As described above, each diagnosis target described above is not a failure such as the storage medium itself such as a hard disk or a memory becoming unusable. However, when a failure occurs in a part of each component, program, or the like that constitutes the stored moving image server 1, the failure may affect the entire apparatus. The storage medium may not operate normally. In such a case, there is a risk that valuable image data stored in the image storage unit 14 such as a hard disk may be lost. Therefore, the purpose of the present invention is to make a backup in advance by predicting a failure. Therefore, the target of self-diagnosis is not necessarily limited to a target directly related to a failure of a storage unit such as a hard disk.
[0045]
<Process flow>
A mechanism for backing up an image in the above configuration will be described. First, each stored moving image server 1 diagnoses the state of its own device by the self-diagnosis unit 17. Next, the self-diagnosis unit 17 transmits the state information to the failure machine diagnosis unit 32 of the base station 3. The trouble machine diagnosis unit 32 collects state information from the accumulated moving image server 1 in each place. The state information transmitted from the stored moving image server 1 to the base station 3 may be the quantitative measurement result itself of the diagnosis target, or may be information that clearly identifies the cause of the failure. When the measurement result is transmitted to the base station 3, the fault diagnosis (prediction) is performed in the fault diagnosis unit 32 of the base station 3 as described above. Alternatively, the self-diagnosis unit 17 of each stored moving image server 1 may perform processing up to determining a failure and transmit information specifying the cause of the failure to the base station 3. The state information may be periodically acquired from the base station side with respect to the stored moving image server.
[0046]
The trouble machine diagnosis unit 32 identifies the stored moving image server 1 having a possibility of failure based on the status information received from each stored moving image server 1. The faulty machine diagnosis unit 32 determines the destination of the specific information of the stored video server 1 that has been specified as a device with a possibility of failure (hereinafter, a device with a possibility of failure will be referred to as a faulty machine for convenience). Delivered to part 33. The destination determination unit 33 determines the stored moving image server 1 as a backup destination. The backup destination determination method is not particularly limited. For example, an ID number is assigned to each stored video server 1, and a device having an ID number next to the ID number of the malfunctioning device is determined as the backup destination. A simple method or a method of preferentially determining a device having a large free space in the image storage unit 14 as a backup destination may be used.
[0047]
When the destination determination unit 33 determines the backup destination device, it passes this information to the duplication instruction unit 34. The duplication instruction unit 34 includes the backup destination information in the stored moving image server 1 having the possibility of failure based on the failure machine identification information received from the failure machine diagnosis unit 32 and the backup destination information received from the destination determination unit 33. Send a copy instruction.
[0048]
In the stored moving image server 1 that has received the duplication instruction, the duplication processing unit 18 generates duplication data of the image data accumulated in the image accumulation unit 14 and sends a duplication data transmission instruction to the information distribution unit 15. . The information distribution unit 15 transmits the duplicate data to the corresponding stored moving image server 1 based on the backup destination information.
[0049]
In this way, duplicate data is transmitted to the image storage server 1 determined as the backup destination by the faulty device. The stored moving image server 1 that has received the copy data stores the received copy data in the image storage unit 14 of its own device. In this way, the image backup process is completed.
[0050]
In addition, the destination determination unit 33 of the base station 3 also has a mail transmission function, so that an e-mail is transmitted to the administrator of the stored moving image server 1 determined as a faulty machine by the faulty machine diagnosis unit 32. Yes. As a result, the administrator can quickly prepare for trouble countermeasures. Alternatively, the destination determination unit 33 may notify the administrator of the stored video server 1 determined as the backup destination of an e-mail. Thereby, it is possible to notify the administrator of the accumulated moving image server 1 in which the replicated data of the other device is stored.
[0051]
According to the second embodiment, since the base station 3 determines the faulty machine and the backup destination of the image data stored in the faulty machine, even when a large number of stored video servers are connected to the network, It is possible to perform backup processing of images stored in each stored moving image server in consideration of the overall balance.
[0052]
In addition, since the backup data is not stored in the base station 3 in a concentrated manner, even when a failure occurs in a part of the image storage server 1, the problem that the influence on the entire backup data is solved. Is possible.
[0053]
In addition, by acquiring and diagnosing the status information of each stored video server 1, before the actual failure occurs, the failure machine (accurately, it is a device with a possibility of failure, not the failure machine) It is possible to perform backup processing before a problem such as data loss occurs.
[0054]
In the above description, the backup destination determined by the destination determination unit 33 has been described as being one of the image storage servers 1. However, the base station 3 and the viewing station 5 are determined as one backup destination device. You may do it.
[0055]
That is, the destination determination unit 33 of the base station 3 may determine a backup destination device from each of the image storage servers 1, or may include the base station 3 and the viewing station 5 that are its own devices. The device may be determined.
[0056]
In the destination determination unit 33, when the base station 3 or the browsing station 5 is selected as a backup destination, information specifying the base station 3 or the browsing station 5 as backup destination information in the duplication instruction transmitted by the duplication instruction unit 34 Is included. Then, the stored moving image server 1 that has received this duplication instruction transmits image duplication data to the base station 3 or the viewing station 5. In the base station 3 and the viewing station 5 that have received the duplicate data, the duplicate data is stored in the storage units 31 and 51, respectively.
[0057]
{Third embodiment}
Next, Embodiment 3 of the present invention will be described with reference to FIG. As shown in FIG. 4, the third embodiment will be described by taking two stored moving image servers 1G and 1H as an example. The stored video servers 1G and 1H have the functions of the stored video server 1 shown in FIG. 1 (the stored video servers 1G and 1H are also collectively referred to as the stored video server 1 as appropriate). A function of accumulating captured images in the image storage unit 14 and a function of distributing captured images are provided.
[0058]
The stored moving image server 1G is installed outdoors and is mainly used for outdoor daytime monitoring. On the other hand, the stored moving image server 1H is installed indoors and is mainly used for indoor monitoring at night.
[0059]
In such a case, the outdoor stored moving image server 1G focuses on the monitoring application in the time zone from 6:00 to 18:00. This time zone is set as the main operating time for the stored video server 1G. That is, the main operating time is a time zone in which the stored moving image server 1 is expected to operate for the original purpose. On the other hand, in the time zone from 18:00 to 6:00, the indoor stored moving image server 1H is the main operating time.
[0060]
Therefore, each stored video server 1 acquires the current time from a built-in timer or the like, so that the stored video server 1H operates as a backup device during the main operation time for the stored video server 1G, and vice versa. In the main operation time for the stored moving image server 1H, the stored moving image server 1G is operated as a backup device.
[0061]
By switching roles according to such time zones, it is possible to operate each of the stored moving image servers 1G and 1H efficiently. That is, in the main operation time zone, it is necessary to use resources such as the CPU and memory of the own device for the main operation purpose, and it is not preferable that the backup processing load of other devices is applied. On the other hand, in the time zone other than the main operating time zone, there is no processing load as the main operating purpose, so the hardware can be used effectively by using hardware resources for backup processing of other devices. is there.
[0062]
In addition, for example, if the system configuration is such that the data in the hard disk is transmitted to the center after the main operation time has ended, sufficient free space on the hard disk can be obtained in a time zone other than the main operation time zone. become. Therefore, the storage device can be effectively used by using this free space for backup.
[0063]
The role of the stored moving image server described above is an example, and a combination such as a stored moving image server used for indoor monitoring use during the day and a stored moving image server used for outdoor monitoring use at night may be used.
[0064]
【The invention's effect】
As explained above, Claim 1 In this invention, since image backup is performed between image storage devices connected via a network, maintenance relating to backup processing is easy. Further, since no special equipment for backup is required, it is possible to construct a backup system at low cost. Furthermore, even when there are a large number of image storage devices, it is different from the form in which backup data is centrally managed in one place, so the influence of a single device failure on the entire backup data can be reduced. It is.
[0065]
And claims 1 In the described invention, since the image of the image storage device determined to have a possibility of failure is backed up, the backup process is performed with higher efficiency according to necessity.
[0066]
And claims 2 In the described invention, since the backup destination device is determined based on the operating state of each image storage device, the backup data is stored in the normally operating device, and the reliability is improved.
[0067]
Claim 3 Or claims 4 In the described invention, it is possible to select a base station or an image browsing terminal as a backup destination device, and the backup system is highly flexible.
[0068]
Claim 5 In the described invention, since an e-mail is notified to the administrator of the apparatus that may have a failure, it is possible to prepare sufficient countermeasures for failure together with the backup processing.
[0069]
Claim 6 In the described invention, since the image storage device is switched to the backup application according to the time zone, the device can be effectively used.
[0070]
Claim 7 In the described invention, whether or not the image storage device is in the main operating time zone is used as a reference for switching to the backup application, and therefore it is possible to prevent the backup processing load from being applied to the image storage device in the main operating time zone. is there.
[Brief description of the drawings]
FIG. 1 is a block diagram showing basic functions of an image storage server.
FIG. 2 is a diagram illustrating an image backup mode according to the first embodiment;
FIG. 3 is a diagram illustrating an image backup mode according to the second embodiment;
FIG. 4 is a diagram illustrating an image backup mode according to the third embodiment;
[Explanation of symbols]
1 Stored video server
3 base stations
14 Image storage unit
15 Information Distribution Department
17 Self-diagnosis department
18 Copying instruction section
32 Fault diagnosis unit
33 Destination determination unit
34 Copying instruction section

Claims (7)

A system for backing up images in an image distribution system comprising first and second image storage devices and a base station,
  The first and second image storage devices are:
  Photographing means;
  Storage means for accumulating images acquired by the photographing means;
  Means for receiving a request from an image browsing terminal connected via a network and distributing the image stored in the storage means to the image browsing terminal;
With
  The first image storage device further includes:
  Means for acquiring status information of the own device;
  Means for transmitting the status information to the base station;
With
  The base station
  Judging means for judging the status of the first image storage device by evaluating the received status information based on a predetermined condition indicating the possibility of failure;
  Instructing means for transmitting a duplication instruction to the first image storage device when it is determined that the first image storage device is likely to fail;
With
  The first image storage device further includes:
  Means for transmitting a copy of the image stored in the storage means of the device itself to the second image storage device via the network when the copy instruction is received;
With
  The second image storage device further includes:
  Means for storing the received copy in the storage means of its own device;
An image backup system comprising: The image backup system according to claim 1, wherein the image distribution system includes a plurality of image storage devices including the first and second image storage devices,
  The determination means includes
  Means for identifying an image storage device in a normal state as the second image storage device from the state information received from each image storage device;
Including
  The instruction means includes
  Means for instructing an image storage device in a normal state specified as the second image storage device as an image backup device;
An image backup system comprising: The image backup system according to claim 1 or 2,
  The instruction means includes
  Means for instructing the base station as a device for image backup instead of the second image storage device;
Including
  The first image storage device further includes:
  Means that, when the base station is instructed as a device for image backup, a copy of the image stored in the storage means of its own device is transmitted to the base station via a network;
An image backup system comprising: The image backup system according to any one of claims 1 to 3,
  The instruction means includes
  Means for instructing the image browsing terminal as a device for image backup instead of the second image storage device;
Including
  The first image storage device further includes:
  Means that, when the image browsing terminal is instructed as a device for image backup, a copy of the image stored in the storage means of its own device is transmitted to the image browsing terminal via a network;
An image backup system comprising: The image backup system according to any one of claims 1 to 4,
  The base station further includes:
  Means for notifying the administrator who manages the first image storage device by e-mail when the copy instruction is transmitted;
An image backup system comprising: A system for backing up an image between a first and a second image storage device,
  The first and second image storage devices are:
  Photographing means;
  Storage means for accumulating images acquired by the photographing means;
  Means for receiving a request from an image browsing terminal connected via a network and distributing the image stored in the storage means to the image browsing terminal;
  A time measuring means for outputting the current time;
With
  When the current time acquired from the time measuring means is a predetermined first time zone, the second image storage device stores a copy of the image stored in the storage means of the first image storage device via the network. When the current time acquired from the time measuring means is in a predetermined second time zone, a copy of the image stored in the storage means of the second image storage device is transferred to the network. An image backup system, wherein backup is performed by transmitting to the first image storage device. The image backup system according to claim 6,
  The first time zone is a main operating time zone of the first image storage device, and the second time zone is a main operating time zone of the second image storage device. Image backup system.

Images