Apparatus and program

Abstract

To provide an apparatus etc. capable of acquiring a captured image which enables a user to easily check the contents of photographing before and after the occurence of an event.SOLUTION: The apparatus comprises: event detection means which detects information indicating the occurence of an event generated by an imaging target; and control means which has a function of, with the detection of the information indicating the occurrence of the event by the event detection means as a trigger, storing captured images in a record period including before and after the moment of detecting the information indicating the occurrence of the event, in a storage medium.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an apparatus, a program, and the like. [Background technology]

[0002] 2. Description of the Related Art There has been proposed a surveillance camera that includes a lens unit and stores image data captured by the lens unit in a removable storage medium (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-197902 A Summary of the Invention [Problem to be solved by the invention]

[0004] Normally, such surveillance cameras continuously capture images of the target object, so in order to check the contents of the footage when something unusual happens, it is necessary to play back the long footage from the beginning and search for the problem scene by fast-forwarding, etc. This makes the review process very time-consuming.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an apparatus capable of acquiring captured images that enable easy confirmation of the captured contents before and after an event has occurred, for example. [Means for solving the problem]

[0006] (1) In order to solve the above problems, the present invention may be an apparatus including an event detection means for detecting information indicating the occurrence of an event emitted by an image capture subject, and a control means having a function of storing, in a storage medium, captured images during a recording period including the time period before and after the moment the information indicating the occurrence of the event is detected by the event detection means.

[0007] In this way, in response to information indicating the occurrence of an event emitted by the imaging target, the contents of the images captured before and after the time of the occurrence of the event can be easily confirmed. For example, in order to confirm the images, a playback means for playing back the stored captured images so that the user can view them may be provided. The playback means may be provided integrally with the control means or may be provided separately. In addition, in the present invention, an imaging means may be provided together with the control means. The imaging means may perform imaging at all times regardless of the occurrence of an event and temporarily store the captured images over a predetermined time. Then, when the control means detects information indicating the occurrence of an event, the control means may control the storage medium to store the captured images captured at a predetermined time before and after the event. In addition, in the present invention, the storage medium may be built into the device in which the control means is provided, but may be provided detachably in the device in the form of, for example, a memory card, a hard disk drive, or the like.

[0008] An "event" may be, for example, an event that occurs when an abnormality occurs. For example, an event may be any of a variety of occurrences, particularly an event that occurs due to a failure in a machine tool operating on a factory production line, a change in state or an abnormality detected by an external sensor, etc. An event may also be an automatic recovery from an abnormal state.

[0009] The "information indicating the occurrence of an event" may be, for example, information indicating a change in state or the occurrence of an abnormality. Specifically, for example, if the imaging target is a machine tool, the information generated when the machine tool detects a failure in the work may be the "information indicating the occurrence of an event". It is particularly preferable to use an alarm signal or an alert signal generated when the machine tool detects a failure in the work as the "information indicating the occurrence of an event". For example, a signal from a signal light connected to the machine tool (for example, a status signal indicating that the signal light is on) or a drive signal for blinking the signal light may be the "information indicating the occurrence of an event". The "information indicating the occurrence of an event" may be an external output signal for notifying the outside of the occurrence of an event such as an abnormality in the imaging target device. Then, the control means may control the storage of the captured image captured by the imaging means in the storage medium in response to a change in these signals. The "information indicating the occurrence of an event" may be configured to include a configuration that detects the occurrence of an event not only by detecting a signal received from the outside but also by detecting the occurrence of an event inside the device. For example, the lifespan and degree of deterioration of the storage medium may be determined inside the device, and a predetermined determination such as that the lifespan is approaching may be treated as the occurrence of an event.

[0010] The "time when an event occurs" may be, for example, the time immediately after information indicating the occurrence of an event is detected.

[0011] The "captured image" may be an image captured within a range in which the cause of the occurrence of an event can be traced.

[0012] The "image" may be, for example, a still image, but more particularly, a moving image. The image may be, for example, a 2D image or a 3D image. For example, the image may be, for example, a black and white image or a color image.

[0013] (2) The imaging target may be a device that performs control to notify humans of the occurrence of an event when the event occurs. For example, at a site such as a factory, a logistics warehouse, or an automated warehouse, the imaging target may be a machine that performs some kind of automatic processing, such as a machine tool or an automatic conveyor. The imaging target may also be a device that is not automated but is expected to be used by general users, such as an automated teller machine (so-called ATM) or a self-checkout. The control means may detect information that these devices emit in conjunction with control to notify humans of the occurrence of an event as information indicating the occurrence of an event.

[0014] (3) Information indicating the occurrence of an event should be an electrical or optical signal emitted by the equipment when an abnormality occurs.

[0015] The "electrical or optical signal transmitted to the device" may be any signal that the device issues when an abnormality occurs, but may be, for example, a binary signal indicating a status such as on / off, an audio signal transmitting analog audio, a pulse train, or a signal repeating a predetermined pattern. In this way, information indicating the occurrence of an event can be reliably received and detected.

[0016] (4) The information indicating the occurrence of an event may be a signal that is emitted by the device in response to an occurrence of an abnormality so as to be recognizable to humans. For example, if the information indicating the occurrence of an event is visual information, the information indicating the occurrence of an event may be detected by an imaging means.

[0017] The "signal emitted so as to be recognizable to humans" may be, for example, auditory information such as a siren, beep, or melody; visual information such as light emission or an image; or motion information such as vibration or impact.

[0018] The equipment can use a function to indicate the occurrence of an event, such as an alarm issued to a person, and record images before and after the occurrence of an abnormality. In particular, when visual or auditory information is detected as information indicating the occurrence of an event, troublesome work such as branching signals is not required when installing the device, and the device can be easily installed and removed.

[0019] (5) The imaging target may emit different information depending on the type of event that has occurred, and the control device may store different recording periods corresponding to the identified information in advance, identify the event that has occurred based on the information indicating the occurrence of the detected event, and store the captured image in the recording period corresponding to the identified event in the storage medium. For example, when detecting an electrical or optical signal emitted by the device in response to an abnormality as information indicating the occurrence of an event, the control device may identify the information indicating the occurrence of the event based on the type, pattern, etc. of the signal. For example, an existing signal for the device may be branched and used.

[0020] In this way, it is possible to identify multiple types of information according to the event that has occurred, and to set an appropriate recording period according to the type of event. For example, for information indicating the occurrence of an event that requires analysis or identification of the cause of the event, it is preferable to set a long recording period before the moment the information is detected, and for information indicating the occurrence of an event that requires attention to the transition after the event occurrence, it is preferable to set a long recording period after the moment the information is detected. The imaging device may control the recording period to be different for each type of information indicating the occurrence of an event, and may store the recording period in advance in association with the type of event.

[0021] (6) The control means may be capable of executing control so that a predetermined period of time from the moment information indicating the occurrence of an event is detected is set as an unresponsive period in which no reaction is made to information indicating the occurrence of a new event. (7) In the case where information indicating the occurrence of an event is continuously emitted after the occurrence of an event, the control means may be capable of executing control so that a predetermined period of time from the moment the continuously emitted information indicating the occurrence of an event stops is set as an unresponsive period in which no reaction is made to information indicating the occurrence of a new event.

[0022] The "non-responsive period" should be a period of time sufficient to confirm that the continuation of information indicating the occurrence of an event has stopped. For example, if the information indicating the occurrence of an event is a pulse train that is continuously repeated in a predetermined pattern, the non-responsive period should be longer than the longest low period in the pattern.

[0023] By providing an invalid response period in this way, it is possible to prevent multiple records from being left when information indicating the occurrence of multiple events is detected within a short period of time. For example, when information indicating the occurrence of multiple events is issued for an event that should be understood as a single event, it is possible to prevent unnecessary records from being left.

[0024] (8) The control means may be capable of executing control such that a predetermined time immediately following a recording period is a monitoring period, and when information indicating the occurrence of a new event is detected during the monitoring period, the end of the monitoring period is treated as the moment when the information indicating the occurrence of the new event is detected. (9) The monitoring period may be set so that a recording period based on the end of the monitoring period overlaps with the immediately preceding recording period.

[0025] When information indicating the occurrence of the next event is detected immediately after the end of a recording period, it is possible to lengthen the recording time combined with the previous recording period while suppressing overlapping of recording periods.

[0026] (10) The control means may sequentially record a series of captured images spanning a predetermined period of time in consecutive addresses in a recording area of ​​the storage medium, and may perform control to increment by 1 an overwrite count value indicating the number of times data is overwritten at the address at which each captured image is recorded.

[0027] In this way, by recording the overwrite count value indicating the number of times of overwriting, it becomes possible to determine the lifespan of a storage medium that breaks down as the number of times of writing increases, such as a NAND type flash memory. In addition, by controlling the sequential recording to consecutive addresses in the recording area, the process of searching for the next writing area during the recording process becomes unnecessary, shortening the writing time, and making it possible to use addresses in the storage area evenly, thereby avoiding excessive use of only a part of the storage area.

[0028] (11) The control means may detect, in the memory area of ​​the storage medium, a captured image whose overwrite count value is different from the overwrite count value recorded for the immediately preceding captured image, and may perform control to overwrite the detected captured image and record the next captured image.

[0029] In this way, it is possible to specify the address to which the next captured image should be written without having to store the address separately. Also, by writing the next captured image from the address specified in this way, it is possible to use the addresses in the memory area evenly, and it is possible to avoid overusing only a portion of the memory area.

[0030] (12) The control means may retain a format count master value indicating the number of times the storage medium has been initialized in a management area of ​​the storage medium that is different from the storage area that stores the captured images, and may transcribe the format count master value as a format count value for each captured image while recording the captured images to consecutive addresses in the storage area of ​​the storage medium. Data for captured images for which a format count value different from the current format count master value has been recorded may be treated as having been erased.

[0031] In this way, the time required for formatting can be shortened. Also, in the case of a storage medium whose deterioration is accelerated by physically erasing the stored data, formatting can be completed by updating only the format master count value, so that shortening of the life of the storage medium due to formatting can be prevented.

[0032] (13) The program of the present invention may cause a computer to function as any one of the devices described above. [Brief description of the drawings]

[0033] [Figure 1] 1 is a schematic diagram showing an imaging device 100 together with a machine tool 2. FIG. [Diagram 2] 1 is a schematic diagram showing an overview of the operation sequence when an event occurs in machine tool 2. FIG. [Diagram 3] 1 is a schematic diagram showing the external appearance of an imaging device 100. FIG. [Figure 4] 1 is a block diagram showing the configuration of an imaging device 100 together with a memory card 200. [Diagram 5] 2 is a schematic diagram showing an example of a recording format of a memory card 200. FIG. [Figure 6] 5 is a diagram showing the relationship between the occurrence of an event and the recording of a captured image in the first embodiment. FIG. [Figure 7] FIG. 11 is a diagram showing the relationship between the occurrence of an event and the recording of a captured image in the second embodiment. [Figure 8] FIG. 13 is a diagram showing the relationship between the occurrence of an event and the recording of a captured image in the third embodiment. [Figure 9] FIG. 13 is a diagram showing normal recording control when a trigger is recognized immediately after the end of a recording period. [Figure 10] FIG. 13 is a diagram showing the relationship between the occurrence of an event and the recording of a captured image in the fourth embodiment. [Figure 11] FIG. 13 is a diagram showing the relationship between the occurrence of an event and the recording of a captured image in the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] [First embodiment] At sites such as factories, logistics warehouses, and automated warehouses, machines that perform some kind of automatic processing, such as machine tools and automatic conveyors, are used. In addition, machines that are not automated but are expected to be used by people who are not familiar with using machines, such as automated teller machines (so-called ATMs) and self-checkouts, are used in general stores. These machines are generally equipped with a function that notifies a person, such as a manager or a supervisor, of the occurrence of an abnormality by using a lamp or an alarm sound when some abnormality occurs. However, even if a manager rushes to the site after an abnormality occurs, if he or she can only see the situation after the abnormality occurs, it may be difficult to take appropriate measures such as identifying the cause of the abnormality and preventing the abnormality from recurring. For this reason, it is common to take images of the machinery and equipment using a video camera or the like before the abnormality occurs, and then check the situation before and after the abnormality occurs by watching the recorded images after the abnormality occurs.

[0035] For example, let us consider a situation where a new manufacturing line using machine tools has been constructed in a factory. When a manufacturing line has just been constructed, the machine tools that make up the line will have various troubles for about 3 to 4 months, so it is necessary to monitor the machine tools and carry out improvement activities to eliminate the causes of the troubles. For example, troubles such as screws dropping or falling over may occur on a screw tightening line. Activities are carried out to eliminate the causes of such troubles, reduce the number of troubles to almost zero, and ensure that products are completed properly. Conventionally, the machine tools were constantly filmed with a video camera, and when an abnormality was later found from the data recorded by the machine tools, the workers would watch the captured images from the beginning.

[0036] An imaging device 100 according to an embodiment of the present invention, which will be described below with reference to the drawings, can be suitably used for capturing images of such machinery and equipment. The imaging device 100 of this embodiment is a device that records video of a machine tool 2 in order to monitor the work of the machine tool 2 operating on a production line in a factory. FIG. 1 is a schematic diagram showing the imaging device 100 together with the machine tool 2. FIG. 2 is a schematic diagram showing an overview of the operation sequence when an event occurs in the machine tool 2. The imaging device 100 is temporarily installed beside the machine tool 2 on a tripod.

[0037] The machine tool 2 to be monitored in this embodiment performs screw tightening work in a manufacturing line. The machine tool 2 repeatedly performs this screw tightening work at a predetermined work cycle (for example, 30 seconds). When the machine tool 2 detects a failure in the work it performs or an abnormality in the equipment, it outputs an alert signal indicating the occurrence of an abnormality. A transition from a normal state to a state different from the normal state, such as a work failure or an abnormality in the equipment, is called an "event." The machine tool 2 normally keeps the alert signal low. On the other hand, when an event occurs, it continuously outputs pulses that alternate between high and low. The alert signal is input to the stacked signal light 21 as a lighting control signal. The stacked signal light 21 is a display or the like in which multiple colored signal lights, such as red, yellow, and blue, can be turned on / off independently. When the signal level of the corresponding control signal is low, the signal light of each color is turned off, and when the signal level is high, the signal light is turned on. In this embodiment, the red light in the stacked signal light 21 is controlled by the alert signal. In this embodiment, the alert signal is input to the stack signal light 21 as a control signal for turning on / off the red light of the stack signal light 21, and the red light blinks in response to the alert signal. After outputting the alert signal, the machine tool 2 stops the work, removes the defective product, and resumes the work, while stopping the alert signal pulse and returning to a normal state as a low state. A series of processes starting from the detection of the failure, through the alert, the stop of the work, and the removal of the defective product, to the resumption of the work may be completed within the work cycle in which the failure was detected, but may not be completed within the work cycle. Until the completion, the alert signal pulse continues to be output continuously without being stopped. The imaging device 100 detects the occurrence of an event when the state of the alert signal first changes from low to high, and captures and records images of a recording period including the time before and after the moment of the event occurrence.

[0038] The video recorded by the imaging device 100 is played back by a dedicated browser, which is display / viewing software that runs on a personal computer. The dedicated browser is a program executed by the personal computer's CPU, and is installed on a personal computer in a management department that is separate from the factory where the imaging device 100 is installed. In addition to playing back the video recorded by the imaging device 100, the dedicated browser can also be used to set various settings such as frame rate, image quality, recording method, and whether or not overwriting is possible, and to format the memory card 200 for the imaging device 100.

[0039] Fig. 3 is a schematic diagram showing the appearance of the imaging device 100, and Fig. 4 is a block diagram showing the configuration of the imaging device 100 together with a memory card 200. The imaging device 100 includes a controller 110, an imaging unit 120, an event input terminal 130, a memory card slot 160, and an image signal output terminal 180 inside a substantially cylindrical housing 105. A screw hole (not shown) for attaching the imaging device to a tripod head or a shooting location is provided in part of the cylindrical side of the housing 105. The imaging unit 120 is disposed inside the housing 105 so that the screw hole faces downward.

[0040] The control controller 110 is an example of the control means of the present invention. The control controller 110 is configured to include a microcomputer equipped with a CPU, main memory such as ROM and RAM, a timer, etc. (not shown). The ROM of the control controller 30 stores various programs such as an image processing program for storing an image captured by the imaging unit 120 in the main memory or a memory card 200 inserted in the memory card slot 160, and an OS (Operation System). The CPU of the control controller 110 performs various controls in accordance with these control programs. In addition, the control controller 110 detects an alert signal, which is information indicating the occurrence of an event input to an event input terminal 130, and executes control according to the event.

[0041] The imaging unit 120 corresponds to the imaging means of the present invention. The imaging unit 120 is provided at one end in the longitudinal direction of the substantially cylindrical housing 105, with the longitudinal direction of the housing 105 as the optical axis. The imaging unit 120 is composed of a lens section 122 and an imaging element 124. The lens section 122 has a zoom lens, and can set the angle of view according to the size of the subject to be photographed and the distance to the subject. The imaging element 124 is a CCD, a CMOS image sensor, or the like, and obtains an image of the subject formed by the lens section 122 as a captured image.

[0042] The event input terminal 130 is a signal input terminal provided on the side of the housing 105. A wiring branched by an electrotap or the like from a connection line that transmits an alert signal for turning on the stack signal light 21 for anomaly notification when the machine tool 2 detects a work failure is connected to the event input terminal 130, and the alert signal is received as a trigger signal indicating the occurrence of an event. The trigger signal is transmitted to the controller 110 and detected as information indicating the occurrence of an event.

[0043] Existing machines, such as machine tools, are provided with a notification function that notifies a person that an event (e.g., an abnormality in the machine) has occurred. The above-mentioned stacked signal light 21 is one example. Other examples of the notification function include a rotating light, a buzzer, a siren, and the like. The imaging device 100 of this embodiment receives a trigger signal via an event input terminal by branching a signal used by the notification function of the machine.

[0044] The image signal output terminal 180 is a terminal that outputs an image signal for displaying an image captured by the imaging unit 120 on an external monitor, and in this embodiment, an HDMI (High-Definition Multimedia Interface, registered trademark) terminal is used.

[0045] The memory card slot 160 is provided at the end of the housing 105 opposite to the imaging unit 120. A memory card 200, which corresponds to a storage medium of the present invention, is inserted into the memory card slot 160. Under the control of the controller 110, a file storing an image captured by the imaging unit 120 is recorded in the memory card 200.

[0046] As shown in FIG. 5, the memory card 200 is divided into a file system area 210 and an image recording area 220 for use. The file system area 210 is a file system that can be read and written by the OS of a personal computer, similar to a general recording medium of a personal computer, and is a partition in the FAT32 format in this embodiment. This file system area 210 stores software of a dedicated browser. When playing back the recorded contents of the memory card 200 on a personal computer, if a dedicated browser is not installed on the personal computer, the dedicated browser can be installed on the personal computer from this file system area 210. The image recording area 220 is a partition of a unique format that cannot be read or written by the OS of the personal computer. This image recording area 220 is divided into a constant recording area 222 and an event recording area 224 for use.

[0047] The constant recording area 222 includes a management area 222A and a storage area 222B. The management area 222A is an area in which various setting information data is recorded by a dedicated browser, and when the imaging device 100 records a captured image, recording is not performed in the management area 222A. In this manner, even if a power interruption or the like occurs during shooting, the setting data in the management area 222A is not lost. The management area 222A records an overwrite count master value MUC, a format count master value MFC, an overwrite upper limit value UL, and the like. The overwrite count master value MUC indicates the maximum number of times that each storage unit in the constant recording area 222 has been overwritten. The overwrite count master value MUC is updated to the same value as the maximum overwrite count value UC in the storage area 222B when recording setting information in the management area 222A of the memory card by a dedicated browser. The format count master value MFC indicates the number of times that the constant recording area 222 has been formatted. The overwrite upper limit value UL indicates an estimate of the number of overwrites that will cause a breakdown in the memory card 200, and this overwrite upper limit value UL can be used as an estimate for determining the life span (i.e., how many more overwrites are possible). This overwrite upper limit value UL differs depending on the type of memory card. When formatting a memory card using a dedicated browser, the user records the overwrite upper limit value UL in the management area 222A by specifying the model number of the memory card to be used or by directly entering the value.

[0048] The memory area 222B is an area for storing captured images captured by the imaging device 100. A header and a footer are provided for one frame of a captured image, and additional information for the captured image of that frame is recorded in the header and footer. Since the recording size of the captured image and the additional information combined is larger than one byte, which is the address assignment unit of the memory card, one frame of the captured image and the additional information are recorded in multiple consecutive addresses. In the example shown in FIG. 5, 32768 bytes (32 kilobytes) are recorded per frame.

[0049] The additional information recorded in the header and footer of each frame includes the image capture time CT of the image of the frame, a format count value FC, an overwrite count value UC ("1" when written for the first time), and a trigger flag TF indicating that the image is captured at the timing when the occurrence of an event is recognized. The format count value FC is a value indicating the number of formatting processes performed on the memory card 200. The overwrite count value UC is a value indicating the number of times data is written to the address. The format count value FC and the overwrite count value UC are used for life management and recording control of the memory card 200. The information recorded in the header and footer may not overlap or may be completely the same, but it is particularly preferable to have only a partial overlap as in the example shown in FIG. 5. By only partially overlapping the contents of the header and footer, it is possible to increase the difficulty of tampering with data including the additional information.

[0050] The controller 110 of the imaging device 100 stores the captured images, which are constantly captured, in the memory area 222B in the order in which they were captured, in consecutive addresses. Specifically, when the captured images are recorded in the memory area 222B for the first time, recording is started in order from the top address of the memory area 222B. For example, as shown in FIG. 5, the captured images are recorded in the order in which they were captured, using consecutive addresses in the memory area 222B, such as addresses 0 to 32767 for the first frame and addresses 32768 to 65535 for the second frame. Then, when the last address of the memory area 222B is reached, the controller 110 returns to the top address of the memory area 222B and continues recording while overwriting the data that has already been written. When recording after the second round, the overwrite count value UC is increased by 1 from the current value and recorded.

[0051] Like the constant recording area 222, the event recording area 224 also includes a management area 224A and a memory area 224B. A format count master value MFC, an overwrite count master value MUC, an overwrite upper limit value UL, etc. are recorded in the management area 224A. Moreover, captured images captured temporally before and after the occurrence of an event are recorded together with additional information in the memory area 224B. The management area 224A and the memory area 224B store the same information as the management area 222A and the memory area 222B, respectively. The additional information recorded here is the same as the additional information stored in the memory area 224B of the constant recording area 222.

[0052] When the controller 110 detects an alert signal received by the event input terminal 130, the controller 110 stores the images captured by the imaging unit 120 during a recording period including the time before and after the moment the alert signal was detected in the memory area 224B in consecutive addresses in the same manner as the recording in the memory area 222B. The recording period before and after the occurrence of an event will be described later.

[0053] By the above-mentioned recording method, writing is performed cyclically at consecutive addresses in the recording area (222B, 224B). As a result, the latest overwrite count value UC is recorded in the additional information of the most recently written frame, and the overwrite count value UC less by one is recorded in the additional information of the next frame. The controller 110 finds the frame where the overwrite count value UC switches for consecutive addresses in the recording area (222B, 224B) and controls the next writing to be performed from that frame. In this way, it is possible to perform recording while overwriting the oldest data as needed. Moreover, by simply finding the frame where the overwrite count value UC switches and controlling the next writing to be performed from that frame, it is possible to overwrite the oldest data as needed without requiring other complicated controls. In addition, the number of overwrites performed to record the imaging data is recorded, and this can be confirmed during playback, so that the overwrite count value UC (and other additional information) can be used to verify whether data has been tampered with. In addition, the recording areas (222B, 224B) can be used evenly, and it is possible to prevent a location that has been overwritten many times locally from becoming a bottleneck and shortening the life of the memory card itself.

[0054] In memory card 200 employing the above recording method, formatting processing, which erases all data already recorded in the recording areas (222B, 224B), is performed using a dedicated browser, which is software that runs on a computer for displaying and viewing captured images recorded by the above method. Formatting processing is performed by incrementing the format count master value MFC recorded in the management areas (222A, 224A) by 1. On the other hand, during formatting processing, no writing or erasing processing is performed on the memory areas (222B, 224B). In imaging device 100, frames in which a format count value FC smaller than the format count master value MFC recorded in the management areas (222A, 224A) is recorded as additional information are treated as having erased data. Specifically, when writing a new captured image to an area where an old captured image is stored, the controller 110 of the imaging device 100 compares the format count value FC recorded as additional information in the old captured image with the format count master value MFC recorded in the management area (222A, 224A). If the format count value FC is smaller than the format count master value MFC, the data (or a fragment of data) of the old captured image is considered to have been erased and may be overwritten, and is written to the area. This control eliminates the need to perform control (e.g., application of a high voltage) to erase data from elements in the recording area (222B, 224B) during formatting, which contributes to extending the life of the elements and speeding up the formatting process.

[0055] The imaging device 100 configured as above is installed to capture an image of the machine tool 2, as shown in Fig. 1. The imaging device 100 is attached to a tripod via a pan head, utilizing a screw hole provided in the lower part of the housing 105. The lens unit 122 provided in the imaging device 100 adjusts the angle of view so that a captured image can be recorded including a range in which the cause of the occurrence of an event can be investigated in the imaging field of view. When adjusting the imaging range, the image signal output terminal 180 of the imaging device 100 is connected to the monitor 3, and the captured image captured by the imaging device 100 is displayed as it is on the screen of the monitor 3 (so-called through image display), and adjustments are made while checking the range displayed on the screen.

[0056] A cable for transmitting an alert signal from the machine tool 2 is connected to the event input terminal 130 of the imaging device 100. This connection enables the imaging device 100 to receive the alert signal, which is information indicating the occurrence of an event.

[0057] The following describes specific operations performed when the monitoring function is executed by the imaging device 100. In the following description, the operations of the components are controlled by the controller 110, even if not specifically stated otherwise.

[0058] 6(a) and (b) are diagrams showing the relationship between the occurrence of an event and the recording of captured images. The imaging unit 120 of the imaging device 100 always captures moving images regardless of the occurrence of an event. The controller 110 controls the memory card 200 inserted in the memory card slot 160 to record captured images from the start of recording to the latest in the constant recording area 222.

[0059] As described above, if a failure occurs in the work performed by the machine tool 2 while constantly capturing moving images, the machine tool 2 detects the failure and outputs a waveform that periodically repeats high and low as an alert signal. Then, this alert signal is input to the stack signal light 21 as a control signal for turning on / off the red light of the stack signal light 21, and the red light blinks in response to the alert signal. The alert signal is also branched and input to the event input terminal 130 of the imaging device 100. When the alert signal, which has been in a low state, is first changed to high, the controller 110 performs control to store the captured images captured by the imaging unit 120 during a recording period from a predetermined time before the time when the event occurred (i.e., the time when the first change of the alert signal from low to high was detected) to a predetermined time after the event occurrence time in the event recording area 224 of the memory card 200. At this time, for the captured image corresponding to the time when the event occurred, a trigger flag indicating that an event occurred at the capture time of the captured image is recorded as additional information.

[0060] With the above-described control, events such as work failures occur by going through the process of the event that causes the failure, the occurrence of the failure, the detection of the failure, and the transmission of information indicating the occurrence of the event (for example, a change in an alert signal). Therefore, in order to investigate the cause of the failure, it is necessary to check images before the event occurred. According to this embodiment, it is possible to check images before the event occurred.

[0061] The above-mentioned "predetermined time" may be, for example, one work cycle of the machine tool 2 (e.g., 30 seconds). In this way, captured images including the start to end of the work cycle in which the event occurred can be stored regardless of the timing of the event occurring within one work cycle. Since captured images taken from the start to the end of the cycle including the time when the event occurred can be stored without omission, it is possible to easily check the cause of a work failure and the subsequent processing. In other words, by checking the image before the event occurred in the cycle in which the event occurred, the cause of the failure can be grasped. Also, by checking the image after the event occurred in the cycle in which the event occurred, it can be checked whether the processing after the event occurred was performed appropriately.

[0062] While controlling the recording of captured images during a recording period in the event recording area 224, the controller 110 also controls the recording of captured images in the continuous recording area 222 in parallel. For captured images recorded in the continuous recording area 222, a trigger flag is recorded as additional information to the captured image corresponding to the time when an event occurred.

[0063] In addition, the controller 110 controls the device so that, after the end of the recording period, even if the alert signal that has been periodically repeating high and low changes to high for a predetermined non-reaction period (e.g., 30 seconds) from when the alert signal last changes to low, the controller 110 does not react to the new change to high and does not treat it as an event occurrence. For example, when the alert signal continues to change even after the end of the recording period as shown in FIG. 6(a), the non-reaction period is from the end of the recording period to when a predetermined period has elapsed since the alert signal last went low. In addition, when the alert signal stops changing during the recording period as shown in FIG. 6(b), the non-reaction period starts when the alert signal last went low and ends when a predetermined period has elapsed after the start. The non-reaction period should be a period sufficient to confirm that the alert signal stops changing. In the above example, multiple rising edges of the alert signal are generated in succession for an event that should be recognized as one event (e.g., a failure in a task), but the first rising edge of these indicates the moment when the event occurred. In such a case, by providing the above-mentioned "non-reaction period", it is possible to prevent the same event from being recorded multiple times. As described above, in the first embodiment, control is performed so that the next trigger is not detected unless a time during or after an event recording has elapsed during which no pulse has been detected is equal to or longer than a predetermined time. This type of operation is called a pulse cancel trigger.

[0064] The captured image recorded by the imaging device 100 in response to the occurrence of an event is played back in a dedicated browser, which is display and viewing software that runs on a personal computer. This dedicated browser is capable of reading the captured image recording area 220, and displays various information (e.g., a trigger flag indicating that an event has occurred, the image capture time, etc.) that has been recorded as additional information together with the captured image in association with the image being played back. The dedicated browser also has a function for searching for the file to be played back using this additional information as a key. Such a dedicated browser makes it easy to investigate the cause of an event and check post-event processing.

[0065] The dedicated browser also displays a notice regarding the lifespan of memory card 200 based on the overwrite upper limit value recorded in the management area (222A, 224A) and the overwrite count value recorded as additional information of the captured image. Specifically, when the overwrite count value reaches 80% of the overwrite upper limit value, a notice is displayed indicating that it is nearing the time to replace memory card 200. When memory card 200 uses an element that tends to break down with an increase in the number of times it is rewritten, such as a so-called NAND type flash memory, the above-mentioned notice can inform the user of the time when replacement is necessary, and it is possible to prevent a situation in which captured images cannot be recorded or played back due to a defect in memory card 200.

[0066] When a manufacturing line is just constructed, for example, for a period of about 3 to 4 months, the machine tools frequently cause trouble, so it is necessary to monitor the machine tools and carry out improvement activities to eliminate the causes of the troubles. However, after the frequency of troubles decreases and the manufacturing line operates stably, monitoring may no longer be necessary. On the other hand, when the frequency of troubles increases in a manufacturing line that was operating stably, it may be necessary to monitor the existing equipment after the fact. For this reason, it is desirable that the imaging device 100 can be easily installed and removed. The imaging device 100 of the present embodiment described above can be easily installed and removed without providing a special configuration for outputting a trigger signal to the equipment to be imaged, such as the machine tool 2.

[0067] In the above-mentioned first embodiment, the recording period is from a predetermined time before the time when the event occurs to a predetermined time after the time when the event occurs, and the non-response period is a predetermined period after the alert signal last changes to low. However, the captured image during the recording period is recorded in the event recording area 224. However, the control when the event occurs can be modified in various ways depending on the device to be imaged, the information indicating the occurrence of the given event, the characteristics of the event to be noted, and the like. In the following, the second to sixth embodiments will be described as the modified examples. Note that the configurations of the imaging devices according to the second to sixth embodiments are the same as the imaging device 100 of the first embodiment except for the parts not described, so that the overlapping description will be omitted and the following description will focus on the differences from the first embodiment.

[0068] Second Embodiment The second embodiment is an operation called a single trigger. In the single trigger, after a trigger is detected, control is performed so that the next trigger is not detected for a predetermined time. As shown in FIG. 7, an equipment or the like that is the imaging target outputs a pulse of an alert signal at the timing of the event occurrence as information indicating the occurrence of the event. This alert signal is input to the event input terminal 130 of the imaging device 100. When the alert signal that has continued in a low state changes to a high state, the controller 110 performs control to store the captured images captured by the imaging unit 120 during a recording period from a predetermined time before the time when the event occurred (i.e., the time when the change of the alert signal from low to high is detected) to a predetermined time after the event occurrence time in the event recording area 224 of the memory card 200.

[0069] When the device to be imaged outputs multiple pulses for one event, the controller 110 controls the device not to react to a new change to high alert signal during a predetermined non-response period (e.g., 30 seconds) from the time the event occurs, and not to treat the change as an event occurrence. By providing a "non-response period" in this way, it is possible to prevent the same event from being recorded multiple times.

[0070] If the device to be imaged does not output multiple pulses for one event, there is no need to provide a non-response period. The image data for the recording period corresponding to each event may be stored in the recording area, assuming that an event occurs for the number of pulses of the alert signal.

[0071] Third Embodiment The third embodiment is an operation called a multi-trigger. In the multi-trigger, when a next trigger is detected during event recording, control is performed to extend the event recording time. As shown in Figs. 8(a) and (b), a single pulse of an alert signal is output by a device or the like that is the imaging target at the timing of the event occurrence as information indicating the occurrence of the event. This alert signal is input to an event input terminal 130 of the imaging device 100. When the alert signal, which has been in a low state, changes to a high state, the controller 110 performs control to store the captured images captured by the imaging unit 120 during a recording period from a predetermined time before the time the event occurred (i.e., the time when the alert signal is detected as changing from low to high) to a predetermined time after the event occurrence time in the event recording area 224 of the memory card 200.

[0072] The above control is the same as in the second embodiment, but as shown in FIG. 8(b), when a single pulse of an alert signal is further input to the event input terminal 130 during the recording period, the controller 110 extends the end of the recording period to a predetermined time after the time the new event occurred.

[0073] Multiple events that occur within a short period of time can be collected into a single event record, preventing multiple events from being recorded with overlapping recording periods, and saving storage capacity. In addition, if the device being imaged continues to generate an alert signal pulse while an abnormality continues, and stops generating the pulse when the abnormality is resolved, a series of images captured from the occurrence of the abnormality to the resolution of the abnormality can be recorded as a single event. As a specific example, when imaging is performed to check whether a series of response procedures from when a signal light starts flashing upon the occurrence of an abnormality to when an administrator stops the flashing of the signal light is appropriate, the drive signal that flashes the signal light can be detected as a signal indicating the occurrence of an event, and the recording period can be extended while the drive signal is repeatedly turned on and off, allowing a series of images to be recorded as a single event.

[0074] [Fourth embodiment] FIG. 9 shows an operation in the case where an event is recorded in a normal recording period based on the timing of the recognition of the trigger when the next trigger is recognized immediately after the end of the recording period associated with the pulse P1 of the first alert signal. As shown in this example, the shorter the time from the end of the previous recording period to the recognition of the next trigger, the longer the overlap period of the two event records becomes, and the more redundant the recording becomes. In contrast, in the fourth embodiment, when the next trigger is recognized immediately after the end of the recording period, control is performed to shift the timing of the event occurrence. FIG. 10 shows the operation. As information indicating the occurrence of the event, a single pulse P1 of the alert signal is output by the device or the like that is the subject of the imaging at the timing of the event occurrence. This alert signal is input to the event input terminal 130 of the imaging device 100. When the alert signal, which had been in a low state, changes to a high state, the controller 110 performs control to store images captured by the imaging unit 120 during a recording period from a predetermined time before the time the event occurred (i.e., the time when it was detected that the alert signal changed from low to high) to a predetermined time after the event occurred, in the event recording area 224 of the memory card 200. The above control is the same as in the second embodiment.

[0075] Then, the predetermined time immediately after the recording period associated with the pulse P1 is set as the monitoring period, and when a single pulse P2 of the alert signal is further input to the event input terminal as information indicating the occurrence of a new event during the monitoring period, the controller 110 treats the end of the monitoring period as the occurrence of the new event, not the time when the pulse P2 was actually detected, and stores the imaging data of the recording period corresponding to the new event in the recording area. In other words, the trigger flag TF is added as additional information to the frame recorded at the end of the monitoring period, and the recording period associated with the pulse P2 is from a predetermined time before to a predetermined time after the end of the monitoring period.

[0076] The monitoring period should be shorter than the time before the event occurs in the recording period. By doing so, the recording period based on the end of the monitoring period overlaps with the previous recording period, making it easier to understand the events captured in the two recording periods. Although individual event records recorded when an event occurs are not basically continuous in time, a slight overlap with the previous recording period makes it easier to understand the events that have occurred when viewing each file in a dedicated browser, etc. Conversely, if there is no slight overlap of files, it is difficult to understand when viewing the video. On the other hand, it is better to reduce the overlapping period to an extent that does not cause difficulty in understanding and lengthen the time recorded as an event. The overlap between the previous and next recording periods should be enough to recognize the connection of the video, for example, about 2 seconds.

[0077] When the above-mentioned recording is performed, a dedicated browser or the like may have a function for playing back the multiple recordings recorded in a chronologically continuous manner. The dedicated browser may play back the multiple recordings in a chronologically continuous manner by referring to the image capture time CT recorded as additional information of each frame in the recording area 224B of the memory card. In addition, when such recording is performed, a dedicated browser or the like may have a function for displaying the relationship between the multiple recordings recorded in a dedicated browser. In order to display the relationship between the multiple recordings in a dedicated browser, the imaging device 100 may record additional information indicating the relationship between the events for the frames recorded during the recording period of the related events. The additional information indicating the relationship between the events may be a common symbol between related events, such as "A" or "B". In addition, the dedicated browser may display, for example, a symbol indicating the relationship, such as "A-1" or "A-2", on the thumbnail of each recording, or may display each related recording in a predetermined direction, such as horizontally, and may display unrelated recordings in other columns. Furthermore, the relationship between the thumbnails displayed side by side may be displayed by surrounding them with a predetermined frame, such as a colored frame. By displaying them in this manner, it becomes easier to understand the events captured during the two recording periods as a single event.

[0078] As described above, in this embodiment, for a trigger that occurs immediately after an event is recorded, the portion that is used as the trigger is shifted by a small amount of time. For example, if the 10 seconds before and after the trigger recognition are recorded, the trigger is recognized for 5 seconds after the 10 seconds after the end of the latter period, but the recording is left as the next event record for the 10 seconds before and after the 10 seconds after the trigger in the previous recording period, which is 5 seconds after the end of the latter period.

[0079] Fifth embodiment The fifth embodiment is similar to the fourth embodiment, but when the next trigger is recognized immediately after the end of the recording period, the timing of the event occurrence is set to the timing of the actual trigger recognition, while the recording periods before and after the event occurrence are controlled to be different from those when a normal trigger is recognized. Specifically, as shown in Fig. 11, the trigger at the time of the event occurrence is not changed, and the recording period before the event is shortened and the recording period after the event is extended.

[0080] As in the fourth embodiment, the predetermined time immediately after the recording period associated with the pulse P1 is set as the monitoring period, and when a single pulse P2 of the alert signal is further input to the event input terminal as information indicating the occurrence of a new event during the monitoring period, the controller 110 records a trigger flag TF for the frame recorded at that timing. In addition, the recording period associated with this pulse P2 is shortened before the trigger recognition time so that the overlap period with the recording period associated with the pulse P1 is a predetermined time (for example, 2 seconds). In addition, the recording period after the trigger recognition time is extended by a time equivalent to the shortened time. The trigger flag TF is added as additional information to the frame recorded at the end of the monitoring period, and the recording period associated with the pulse P2 is from a predetermined time before to a predetermined time after the end of the monitoring period. The overlap between the previous and next recording periods may be sufficient to recognize the connection of the images, and may be, for example, about 2 seconds. It is also possible not to extend the recording period after the trigger recognition.

[0081] In addition, when the above-mentioned recording is performed, it is preferable to provide a function for playing back the multiple recordings in a time-series manner in a dedicated browser or the like, using the same method as described in the fourth embodiment. It is also preferable to provide a function for displaying the relationship between the multiple recordings in a dedicated browser or the like.

[0082] The control at the time of event occurrence in the first to fifth embodiments described above may be selectively executed by a single imaging device 100 through settings. For example, settings related to control at the time of event occurrence may be recorded in the management area 222A of the memory card 200 using a dedicated browser or the like, and the imaging device may control the occurrence of an event corresponding to the settings.

[0083] Sixth Embodiment The imaging device 100 according to the sixth embodiment identifies the type of event and performs different control depending on the type of event. When an event occurs, the device or the like that is the subject of imaging outputs an alert signal with a different pattern depending on the type of event as information indicating the occurrence of the event. The imaging device 100 stores the pattern of the alert signal in advance in the storage unit 140, and stores event setting information in the storage unit 140 in association with the pattern, defining control when an event occurs. The operation when an event occurs may be the control in the above-mentioned first to fifth embodiments or a combination of these, and the length, start, end, etc. of the recording period, non-response period, and monitoring period in each embodiment may be arbitrarily settable.

[0084] In the imaging device 100 in which the operation at the time of event occurrence is defined in this manner, when an alert signal of a certain pattern is input to the event input terminal 130, the control controller 110 consults the memory unit 140 for the pattern of the input alert signal, and performs control to record the captured images of the recording period including the time before and after the event occurrence in the event recording area 224 of the memory card 200 in accordance with the event setting information corresponding to the pattern.

[0085] The control of event recording performed by the imaging device 100 when an event occurs may vary depending on the characteristics of the event, the content of interest, the form of information indicating the occurrence of an event emitted by the device, etc., but in this embodiment, event recording can be performed using control that is predefined according to the type of event.

[0086] The imaging device 100 may record information indicating the type of event together with the captured images during the recording period. The information indicating the type of event may be recorded, for example, as additional information of the captured image corresponding to the event occurrence. Even if different control is not performed according to the type of event as in the first to fifth embodiments, it is preferable to identify the event that has occurred and record information indicating the type of event together with the captured image.

[0087] The imaging device 100 described above can eliminate the need to manually input information indicating the type of event. Therefore, in a case where an apparatus installed in a remote factory sends images stored at the time of an event to a management department or the like in a lump, and the contents of the images are checked by the management department, the side sending the file obtained by shooting with the imaging device 100 can send the file in which information indicating the type of event is automatically recorded as is. Also, the side checking the sent image can handle the file with information indicating the type of event reliably recorded. Therefore, the labor of both the sending side and the receiving side can be reduced.

[0088] If a corresponding pattern is not stored in the storage unit 140, a predetermined control (for example, the control in the first embodiment) may be performed.

[0089] When recording as described above, it is advisable to display information indicating the type of event corresponding to the captured image being displayed in a dedicated browser or the like for displaying and viewing the captured image. By displaying in this way, it becomes easier to understand the events shown in the image. [Modifications of the embodiment]

[0090] The present invention is not limited to the above-described embodiments, and the present invention includes combinations, modifications, improvements, etc. For example, the lengths of the recording period, non-response period, and monitoring period described in the above-described embodiments are arbitrary, and may be freely set by the user.

[0091] In each of the above embodiments, the imaging target may be any device that controls the device to notify humans of the occurrence of an event such as an abnormality, but the imaging device 100 is particularly effective when the imaging target is a machine tool. For example, in a factory, a logistics warehouse, an automated warehouse, or other similar site, the imaging target may be a machine tool, an automated conveyor, or other machine that performs some kind of automatic processing. In particular, when constructing and starting up such an automatic processing system, the imaging device described in each embodiment is used to solve various problems that arise, and improvement activities are carried out to solve the problems. The imaging device is suitable as a system that records images to investigate the causes of problems until they are solved.

[0092] Furthermore, devices that are not automated but are expected to be used by general users, such as automated teller machines (so-called ATMs) and self-checkouts, may be imaged. An error caused by a user using the device incorrectly or an alarm generated when fraudulent use occurs can be used as information indicating the occurrence of an event, and this is preferable because it can be used to check the usage status when an error occurs and to record the situation in which fraud has occurred. However, this is more effective for devices such as self-checkouts that link multiple cash registers and a management system and have different specifications depending on the customer or location, such as for each store, than for mass-produced devices that operate independently, such as automated teller machines (so-called ATMs).

[0093] In particular, this is particularly effective in a system that has a function of notifying a person such as a manager or a supervisor of the device of the occurrence of an abnormality by a lamp or an alarm sound when some abnormality occurs. In the first embodiment, by using a branched wiring such as an electrotap to branch a connection line to a device for notifying a person of an abnormality in the device, it is possible to record an image including an abnormality in the device without adding a function to output a new event signal to the device. It is preferable that the imaging device 100 recognizes the occurrence of an event by using an optical signal or the like used by the device for notifying a person of an abnormality, or information that a person can recognize by sight, hearing, or the like, and it is particularly preferable that the occurrence of an event is determined from a signal line to a device for notifying a person.

[0094] In each of the above embodiments, any information may be received as information indicating the occurrence of an event, but it is particularly preferable to branch a signal to the stacked signal light 21 connected to the machine tool 2 and receive it as information indicating the occurrence of an event. Other information may be used as information indicating the occurrence of an event. For example, if the device to be imaged has a function of outputting an external output signal for notifying the outside of the occurrence of an event such as an abnormality, this external output signal may be used as information indicating the occurrence of an event. When a branched signal or an external output signal is used as information indicating the occurrence of an event, the imaging device 100 can reliably detect information indicating the occurrence of an event since the signal is received via a physically connected wire or the like. This is particularly preferable when the imaging device 100 is permanently installed and does not require much effort in installation and removal.

[0095] When a branched signal or an external output signal is used as information indicating the occurrence of an event, the signal may be a continuous pulse as in the first embodiment or a single pulse as in the second embodiment, or may be a status signal indicating an ON / OFF state (e.g., two values, high and low), a pulse train repeated in a predetermined pattern, an analog signal such as an audio signal, or the like.

[0096] In the case of controlling to provide a non-response period as in the second embodiment, when a pulse train repeated in a predetermined pattern is detected as an alert signal indicating the occurrence of an event, the non-response period should be set longer than the longest low time in the pulse train pattern, thereby making it possible to prevent the occurrence of a new event from being recognized while the alert signal is continuing.

[0097] When a pulse train repeated in a predetermined pattern is received as an alert signal indicating the occurrence of an event, the predetermined pattern may be stored in advance, and an event may be detected as occurring when a pulse train of a pattern matching the stored pattern is input. In this case, the pattern to be stored in advance may be manually input by the user, but it is particularly preferable to provide a learning mode that learns and stores the pattern of the alert signal actually input to the event input terminal 130. By providing such a learning mode, the task of registering a pattern in the imaging device 100 becomes easier, and the imaging device 100 becomes easier to install.

[0098] The imaging device 100 may be installed so that a plurality of devices are within the imaging field of view of the imaging unit 120, and the logical sum of alert signals from the plurality of devices may be input to the event input terminal 130. In this manner, a single imaging device 100 can capture images of situations when an event occurs in a plurality of devices.

[0099] Also, the imaging device 100 may be provided with a light receiving element for detecting the emission of the signal light, and the emission of the signal light may be detected as information indicating the occurrence of an event. The imaging device 100 may be installed so that the signal light is within the imaging field of view of the imaging unit 120, and the imaging unit 120 may detect the emission of the signal light as information indicating the occurrence of an event. In this case, the control controller 110 may analyze the captured image at any time to detect the emission of the signal light. In this way, in a configuration in which visual information is detected as information indicating the occurrence of an event, troublesome work such as branching a signal is not required when installing the imaging device, and the installation is easy and removal is also easy. In addition, when detecting information indicating the occurrence of an event in a captured image, a special configuration such as a sensor is not required on the imaging device side, and therefore the installation is easy. Therefore, it is particularly preferable when the imaging device 100 is temporarily installed, such as for a period until a trouble in a newly launched production line is resolved.

[0100] Furthermore, when capturing an image of a device that emits an alarm sound such as a siren or buzzer when an abnormality occurs, a microphone for detecting the alarm sound may be provided in the imaging device 100, and the alarm sound of a rotating light may be detected as information indicating the occurrence of an event. In this manner, a configuration that detects audio information as information indicating the occurrence of an event does not require troublesome work such as branching signals when installing the imaging device, and is easy to install and remove. Therefore, it is particularly preferable when the imaging device 100 is installed temporarily, such as until a problem is resolved in a newly launched production line.

[0101] In addition, in a configuration in which different controls are performed depending on the type of the event that has occurred, as in the sixth embodiment, the method of identifying the event is not limited to the method described in the sixth embodiment. For example, if the device to be imaged has a function of outputting information indicating the type of event, such as an error code indicating the type of abnormality, to the outside, the imaging device 100 may be configured to include an event identification information input terminal for inputting the information indicating the type of event. Then, the event that has occurred may be identified based on the information input to the event identification information input terminal.

[0102] As another example, when a device to be imaged by the imaging device 100 outputs multiple types of external output signals, the imaging device may identify the type of event according to the received external signal. Specifically, the type of event may be identified according to the signal that controls each color (red, yellow, blue) of the stacked signal lights. In this way, for example, when a signal that turns on a red signal light occurs, it is assumed that a serious abnormality has occurred, and the recording period is set so that the period before the light is turned on is relatively long, and when a signal that turns on a yellow signal light occurs, it is assumed that an abnormality may subsequently occur, and the recording period is set so that the period after the light is turned on is relatively long.

[0103] In a configuration in which visual information such as the illumination of a signal light is detected as information indicating the occurrence of an event, it is preferable to identify the type of event by color, position, temporal light emission pattern, etc.

[0104] In the sixth embodiment, the information indicating the type of event may be recorded in any manner, but it is particularly preferable to record the information indicating the type of event as additional information of the captured image. The method of recording the information indicating the type of event is not limited to this. For example, the information indicating the type of event may be used as part of the name of the file. By including the information indicating the type of event in the file name, it is possible to easily grasp the contents of the captured image stored in the file without loading the file into a dedicated browser. In addition, an error code is embedded in the header of the frame when the event occurs in the moving image to be recorded. By searching for the frame in which the error code is embedded during playback, it is possible to quickly check the image at the moment the event occurs. For example, the information indicating the type of event may be embedded in the image as a watermark. In this way, the information indicating the type of event can be embedded without increasing the size of the file and without any visible effect on the image. In addition, it is possible to make it difficult to tamper with the information indicating the type of event. As another example, the information indicating the type of event may be embedded as characters superimposed on the image.

[0105] In each of the above embodiments, the imaging unit 120 captures a moving image as an image, but may capture, for example, a still image. The image may be, for example, a 2D image or a 3D image. The image may be, for example, a black and white image or a color image. The lens section of the imaging unit 120 may be a short focal length lens instead of a zoom lens.

[0106] In each of the above embodiments, any storage medium may be used, but it is particularly preferable to use the memory card 200 inserted into the memory card slot 160. In addition, instead of a memory card, other storage devices such as a hard disk drive may be used. In addition, the storage medium is not limited to a removable one, and may be built in the housing 105 in a non-removable form. In addition, the captured image may be stored in a storage area provided on a communication network as a storage medium. However, the best configuration is to store the captured image in a storage medium such as the memory card 200 that is removable from the imaging device 100 described above. In particular, when a manufacturing line has just been constructed in a factory, for a period of about 3 to 4 months, in a temporary case such as when monitoring for trouble, it is possible to simply install and record with the imaging device without building a large-scale system. In addition, when checking the recorded captured image, the memory card or the like can be removed from the imaging device and played back on a personal computer, etc., so that the trouble of reinstalling it each time it is checked can be eliminated. In addition, not only in a temporary case, but also when an event does not occur so frequently, it is possible to easily capture the situation when an abnormality occurs in the machine tool without construction of a large-scale system.

[0107] In the above embodiment, the recording destination for temporarily recording the captured image is arbitrary, and for example, the captured image may be temporarily recorded in a memory element such as an SDRAM built into the imaging device 100, and when an event occurs, the captured image temporarily recorded in the memory element may be finally recorded in the event recording area 224 of the memory card 200. However, as in the above embodiment, it is particularly preferable to record the captured image constantly captured by the imaging unit 120 in the constant recording area 222 of the memory card 200, and record the captured image when an event occurs in the event recording area 224 of the memory card 200.

[0108] Furthermore, captured images for which a predetermined time has passed since the image was captured may be stored in the continuous recording area 222 while reducing the storage size by, for example, lowering the frame rate (for example, one frame per second), lowering the resolution, converting to monochrome, etc. In this way, it is possible to save the storage capacity per unit time required for continuous recording when no event is occurring.

[0109] In the above embodiment, whether or not to perform continuous recording is optional, but it is particularly preferable to record captured images during a recording period associated with the occurrence of an event in the event recording area and record captured images continuously in the continuous recording area. In addition, the captured images recorded when an event occurs should be recorded with a larger amount of information than the captured images recorded continuously, by increasing the frame rate, decreasing the compression rate of the image file (or not compressing it), increasing the image quality of the image file (for example, HD (High Definition) images), making it a color image, etc. Conversely, the captured images recorded continuously may be recorded with a smaller amount of information than the captured images recorded when an event occurs, by decreasing the frame rate, increasing the compression rate of the image file, decreasing the image quality of the image file (for example, VGA images), making it a black and white image, etc.

[0110] In the above first embodiment, an example was described in which a dedicated browser executed on a personal computer separate from the imaging device 100 is used as a display viewing means, but the imaging device 100 may also be provided with a playback means integrated into the housing 105 for playing back and displaying captured images.

[0111] In the first embodiment, the imaging device 100 may be fixed by any method, but a simple method is particularly preferable. In particular, it is preferable to fix the imaging device 100 by a fixing means that is easy to attach / detach, such as a clip, a clamp, a Velcro tape, or an adhesive mat. In the case of temporarily installing the imaging device 100, such as for a period until a trouble is resolved in a newly launched production line, it is particularly preferable to fix the imaging device 100 by such a fixing means that is easy to attach / detach. In addition, it is preferable that the fixing means is attached to an existing structure such as a protective frame or a pillar provided around the equipment to be imaged. In this way, the imaging element can be easily temporarily installed and easily removed.

[0112] In the above first embodiment, an example was described in which a format count master value indicating the number of times the memory card has been formatted is recorded in the management area of ​​the memory card. However, if the memory card can be identified by unique identification information or the like, the format count master value may be recorded in a personal computer that runs a dedicated browser program that formats the memory card, and the format count master value stored in the personal computer may be incremented by 1 each time the memory card is formatted.

[0113] In the first embodiment, the overwrite count master value recorded in the management area of ​​the memory card may be updated by any method, but it is particularly preferable that the overwrite count master value be updated by a dedicated browser. Note that the overwrite count master value may be updated by the imaging device 100. In this way, the latest overwrite count master value can be recorded in the management area without using a dedicated browser.

[0114] In the first embodiment, the method of notifying the information about the lifespan of the memory card is arbitrary, but it is particularly preferable to display the information about the lifespan of the memory card on a dedicated browser using the overwrite count value and the overwrite upper limit value recorded in the memory card. Such information about the lifespan may also be notified by the imaging device. For example, if the imaging device has a liquid crystal screen, it is preferable to display the information about the lifespan on the liquid crystal screen. If the imaging device has a monitor lamp that indicates the operating state, it is preferable to notify the information about the lifespan by turning on or blinking the monitor lamp. If the imaging device has a sound source such as a buzzer, it is preferable to make the sound source emit a sound to notify information about the lifespan.

[0115] The timing of notifying the notification regarding the lifespan in the imaging device may be any timing. For example, it may be when the power is turned on, or it may be constantly monitored and notified. However, if the frequency of overwriting is not high, it is particularly preferable to periodically (for example, once a week) compare the overwrite count value with the overwrite upper limit value and notify when the condition is met. Furthermore, when the imaging device recognizes that the condition for notifying the notification regarding the lifespan is met, it is preferable to treat the satisfaction of the condition for notifying the notification regarding the lifespan as the occurrence of an event, record the captured image in the event recording area, and record information indicating the type of event indicating that the condition for notifying the notification regarding the lifespan is met together. In this way, the captured image caused by the satisfaction of the condition for notifying the notification regarding the lifespan is mixed into the record of the captured image caused by the event that occurred in the device to be imaged, making it easier for the administrator to notice that the lifespan is approaching.

[0116] In the first embodiment, the condition for providing the notification regarding the lifespan may be any, but it is particularly preferable to display the notification regarding the lifespan when the overwrite count value reaches 80% of the overwrite upper limit value. Also, for example, an index indicating the degree of wear may be calculated using the overwrite count value and the format count value, and the notification regarding the lifespan may be displayed according to the result of comparing this with the overwrite upper limit value. For example, when formatting puts stress on the memory area of ​​the memory card and accelerates deterioration compared to normal overwriting, it is preferable to calculate an index indicating the degree of wear by weighting the format count value more than the overwrite count value.

[0117] In the first embodiment, the method of specifying the overwrite upper limit value indicating the approximate lifespan of the memory card is arbitrary, but it is particularly preferable that the user specifies the overwrite upper limit value of the memory card to be used and stores it in the management area (222A, 224A). When the recording medium has information regarding the lifespan stored in advance, this information may be used to provide guidance regarding the lifespan.

[0118] The method of recording to a memory card described in relation to the first embodiment can also be applied to a drive recorder for a vehicle. In this case, it is preferable to record the image in front of the vehicle at all times and to record an event triggered by an impact, acceleration, or the like that corresponds to an accident. [Explanation of symbols]

[0119] 1. Imaging system 2 Machine tools 3 Monitors 100 Imaging device 105 Case 110 Controller 120 Imaging unit 130 Event input terminal 160 Memory card slot 200 Memory Card

Claims

1. a function of recording data representing a captured image in a storage medium and recording the number of times the data representing the captured image is overwritten in the storage medium; a function of notifying a user of a guide regarding the life of the storage medium based on the number of overwrites recorded on the storage medium; a function of recording the number of times the storage medium has been formatted on the storage medium; having The function of notifying the guidance is When an index indicating a degree of wear calculated by weighting the number of times data indicating the captured image is overwritten onto the storage medium and the number of times the storage medium has been formatted satisfies a condition for notifying the notification regarding the lifespan, a notification regarding the lifespan of the storage medium is issued. Device.

2. A function of notifying a user of information regarding the life of a storage medium that is removable from an imaging device, the storage medium recording data representing an image captured on the storage medium and recording the number of times the data representing the image captured on the storage medium has been overwritten and the number of times the storage medium has been formatted, the function comprising: a function of notifying a notification regarding the lifespan of the storage medium when an index indicating a degree of wear calculated by weighting the number of times data indicating the captured image has been overwritten onto the storage medium and the number of times the storage medium has been formatted satisfies a condition for notifying the notification regarding the lifespan of the storage medium; An apparatus having the above configuration.

3. A program for causing a computer to function as the device according to claim 1 or 2.

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