JP2020059340A - Special signal detector - Google Patents

Abstract

To provide a special signal detector that can easily and reliably detect light emission from a special signal light emitting device.SOLUTION: Whether a captured image includes a light emission operation of a special signal light emitting device 200 which flashes at a prescribed cycle is grasped through extraction of a frequency related to brightness by an image processing unit 20. By setting a processing target in the image processing unit 20 as a partial image (continuous partial image) including a plurality of frames obtained by dividing the continuous image into image areas at this time, it is possible to handle situations where, for example, two special signal light emitting devices 200 flashing differently for half a cycle are captured at once, and the flashing operations of each special signal light emitting device cancels out the other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a special signal detection device for detecting light emission in a special signal light emitting device.

  In a railroad traffic signal, which is a device for transmitting train operation information to a train driver, the signal is transmitted by the driver visually confirming whether a colored light is on or off. For this reason, in order to confirm whether or not the driver has overlooked the railroad traffic signal, for example, an infrared light emitter is attached to the railroad traffic light, and an infrared video camera captures infrared light emitted from the infrared light emitter. (See Patent Document 1). In Patent Document 1, a railway traffic light is a railway color light traffic light, a sign or a special signal light emitter. That is, the special signal light emitting device is included in one aspect of the railway signal device.

  Further, there is also known a device for detecting disconnection in the internal structure so that the existing cable of the special signal light emitting device or the like can be used as it is when confirming whether or not the special signal light emitting device is visually approved (see Patent Document 2).

  However, as in the above-mentioned Patent Document 1, in order to use the infrared light emitting device, it is necessary to make a modification such as mounting the infrared light emitting device on an existing device such as a traffic light that emits light, and the time and labor for the modification are enormous. There is a problem that it will become something. Also in the above cited document 2, it is considered necessary to newly provide a structure for detecting disconnection.

  Furthermore, when two special signal light emitters are captured at one time, if the blinking cycles between the two special signal light emitters are shifted by a half cycle, the overall emission brightness is made uniform, and the blinking operation is performed. May not be captured accurately.

Japanese Patent No. 4925987 JP, 2005-178357, A

  The present invention has been made in view of the above points, and an object of the present invention is to provide a special signal detection device that can easily and surely detect light emission from a special signal light emitting device.

  In order to achieve the above object, the special signal detection device according to the present invention provides an amplitude data with respect to a frequency of luminance for an image capturing unit that captures a continuous image and a partial image including a plurality of frames obtained by dividing the continuous image into image regions. And a determination unit that determines whether or not the special signal light emitting device that blinks at a predetermined cycle emits light based on the extraction result of the partial image.

  In the special signal detection device, by extracting the amplitude data with respect to the frequency of the brightness of the continuous image acquired by the imaging unit, in the captured image, the emission of flashing light that blinks at a predetermined cycle in the special signal light emitting device. It is possible to accurately grasp whether or not a motion is included. In this case, since the judgment based on the frequency can absorb the influence of the backlight, the shaking of the image, and the like at the time of image capturing, it can be made highly robust against the external environment. Further, in this case, the processing target in the image processing unit is a partial image composed of a plurality of frames obtained by dividing a continuous image into image regions, so that, for example, two special signal light emitters blinking at different half cycles are at once. Even in the case where the flashing operation of each special signal light emitting device is canceled out after being imaged, it is possible to capture only one of these, and a more reliable special signal light emitting device. Can detect the emission of light. Further, in this case, it is not necessary to attach, for example, an infrared light emitter or a structure for detecting disconnection to the special signal light emitter to be imaged, and desired detection can be performed with a simple configuration.

  In a specific aspect of the present invention, the image processing unit performs Fourier transform processing on the entire partial image to extract data. In this case, the special signal light emitting device can be detected by performing the Fourier transform processing on the entire partial image.

  In another aspect of the present invention, the image processing unit has an image division processing unit that divides a continuous image into a plurality of image regions to create a plurality of partial images, and each partial image created by the image division processing unit. Extract the amplitude data to. In this case, the light emission can be detected for each partial image obtained by dividing.

  In still another aspect of the present invention, the determination unit determines whether or not the special signal light emitting device emits light for each partial image created by the image division processing unit. In this case, the special signal light emitting device can be determined for each partial image obtained by division.

  In still another aspect of the present invention, the image processing unit, when it is determined that there is no blinking in the special signal light emitting device in the determination result of the determination unit based on the entire continuous image, determines that the image division processing unit does Create. In this case, when the blinking of the special signal light emitting device is not detected in the detection based on the entire continuous image, a partial image is created and the special signal light emitting device can be detected based on the partial image.

  In still another aspect of the present invention, the image processing unit determines that the special signal light emitter is in the lighting state and is not in the blinking state based on the wavelength band characteristics of the light in the determination result of the determination unit based on the entire continuous image. In this case, the image division processing unit creates a plurality of partial images. In this case, when the state of the special signal light emitter is unknown by detection based on the entire continuous image, a partial image can be created and the special signal light emitter can be detected based on the partial image.

  In still another aspect of the present invention, the image processing unit determines whether the partial image is extracted if the blinking state is not determined even after performing the amplitude data extraction for the plurality of partial images created by the image division processing unit a predetermined number of times. Finish the creation. In this case, the final judgment can be made after extracting the amplitude data a predetermined number of times for the partial image.

  In still another aspect of the present invention, the image processing unit is configured such that, among the plurality of partial images created by the image division processing unit, the partial image determined to have the special signal light emitter turned off in the determination result of the determination unit. The subsequent processing is unnecessary. In this case, part of the processing can be omitted, and the processing can be simplified.

  In still another aspect of the present invention, the image processing unit changes the extraction method of the partial image according to the determination result of the determination unit. In this case, the extraction method can be changed to perform a new detection, and thus a new determination can be made regarding the special signal light emitting device.

  In still another aspect of the present invention, the determination unit determines whether or not to change the partial image extraction method according to a temporal change regarding the extraction result of the amplitude data in the image processing unit. In this case, it is judged from the change over time regarding the extraction result, for example, that there is a temporary change in luminance due to the influence of telephone poles, trees, etc. existing near the line, and whether the extraction method should be changed accordingly. By determining that, more accurate detection becomes possible.

  In still another aspect of the present invention, the determination unit is a special signal that emits light when amplitude data having peaks is extracted at different timings in one partial image and another partial image in which different image regions are extracted. It is determined that there are multiple light emitting devices. In this case, a plurality of special signal light emitters are detected.

  According to still another aspect of the present invention, the determination unit includes a notification unit that performs notification when it is determined that the special signal light emitting device emits light. In this case, the occurrence of an abnormal situation due to the operation of the special signal light emitting device can be notified on the side of the special signal detecting device by a method different from the transmission by the special signal light emitting device.

  In yet another aspect of the present invention, the notification unit is a voice unit that issues an alarm. In this case, the occurrence of an abnormal situation due to the operation of the special signal light emitting device can be notified by voice by an alarm on the side of the special signal detecting device.

It is a conceptual diagram for explaining an outline of an example of a special signal detection device according to the first embodiment. It is a front view showing an example about the appearance of a special signal light emitter. It is a block diagram for explaining an example of 1 composition of a special signal detecting device. It is a conceptual diagram shown about the extraction of the partial image which consists of a some frame which divided | segmented the continuous image for every image area. (A) is a conceptual diagram of an image composed of a plurality of frames to be processed, and (B) is data showing amplitude data with respect to frequency of luminance obtained from a processing result of an image composed of a plurality of frames. Is. (A) is an image view conceptually showing an example in which a plurality of special signal light emitters are included in one image, and (B) and (C) are a plurality of special signal light emitters simultaneously. It is a conceptual top view for demonstrating an example about the situation imaged. (A) to (C) are graphs for conceptually explaining the state of the cycle shift when two special signal light emitters blink. It is a graph for conceptually explaining the difference in the extraction of amplitude data due to the deviation of the cycle between two blinking special signal light emitters. (A) And (B) is an image figure which shows notionally an example of a mode that a continuous image in the situation where a plurality of special signal light emitters are imaged simultaneously is divided for every image field. It is a flow chart for explaining an example about operation of a special signal detecting device. It is a conceptual diagram shown about an example of image processing in the special signal detecting device concerning a 2nd embodiment. It is a flow chart for explaining an example about operation of a special signal detecting device. (A) is a conceptual diagram showing an example of image processing in the special signal detection device according to the third embodiment, and (B) and (C) are conceptual diagrams for explaining a modified example. It is a conceptual diagram for demonstrating another one modification. (A)-(C) is a graph for conceptually explaining the difference in change over time regarding the operation detection of the special signal light emitter.

[First Embodiment]
An example of the special signal detection device according to the embodiment of the present invention will be described below with reference to FIG. 1 and the like. FIG. 1 is a conceptual diagram for explaining an outline of an example of the special signal detection device 100 according to the present embodiment. In FIG. 1, a train TR of a railway equipped with the special signal detection device 100 and a train TR are It shows a state of a special signal generation system SG on the ground side including a special signal light emitting device 200 (hereinafter, the special signal light emitting device is also simply referred to as a special device) installed beside a track RR which is a dedicated traveling route. . In particular, here, when the special signal light emitting device 200 installed beside the track RR on which the train TR runs causes a blinking operation of the red light indicating the occurrence of an abnormal situation, this is a special signal mounted on the train TR. The state in the case of confirming in the detection device 100 is schematically shown.

  As a premise of the above configuration, in the illustrated example, first, the special signal detection device 100 mounted on the train TR is installed ahead of the moving direction of the train TR as indicated by an arrow A1. More specifically, as shown in a partially enlarged manner, the special signal detection device 100 includes, for example, an imaging unit 10 configured by a camera or the like, and is used to notify the inside of the train TR (especially the driver). The notification unit IP includes a voice unit 30 and a display unit 40 configured by a speaker, a monitor, and the like, and a management device MC for centrally controlling these units. The special signal detection device 100 arranges the image pickup unit 10 toward the front in the traveling direction of the train TR, captures the special signal light emitter 200 in the front, and manages the image data of the special signal light emitter 200 in the image pickup unit 10. By performing processing in the MC, it is confirmed whether the blinking operation indicating the occurrence of an abnormal situation is performed, and if necessary, the notification unit IP notifies the inside of the vehicle based on the confirmation result.

  As shown in the figure, the imaging unit 10 here is provided with a wavelength filter FI on the front side that takes in light. The wavelength filter FI has a transmission characteristic corresponding to the wavelength band of the light emitted by the special signal light emitter 200. As a result, the components of the light from the special signal light emitter 200 can be reliably taken in, while the other components can be blocked by the wavelength filter FI. That is, by providing the wavelength filter FI, the extraction of the wavelength band of the light to be the target of the image data acquired by the image pickup unit 10 becomes remarkable.

  Here, as described above, FIG. 1 illustrates not only the above-described special signal detection device 100 but also the ground-side special signal generation system SG including the special signal light emitter 200. Here, as an example, the special signal generation system SG is provided at the railroad crossing CR, and has the special signal light emitter 200 that is activated when the emergency button EB is pressed, in addition to the emergency button EB interlocking with the railroad crossing CR. It is composed. In this case, as shown in the figure, for example, when a vehicle VE such as an automobile is stuck inside the railroad crossing CR and the emergency button EB is pressed, the special signal light emitting device 200 starts a predetermined blinking operation with red light, thereby causing the railroad crossing. The train TR approaching the CR is informed of the occurrence of an emergency by a blinking display.

  Here, regarding the notification of an emergency occurrence due to the blinking operation of the special signal light emitting device 200, even if the special signal light emitting device 200 is operating normally, for example, the special signal light emitting device 200 installed in the outdoors and the train TR If it is difficult to confirm it with the naked eye because the position of and is in the condition of backlighting, or it is difficult to image the front due to severe vibration due to running, in the train TR, the human visual observation and the image data of the camera itself Only by itself, there is a possibility that the operation of the special signal light emitting device 200 cannot be accurately captured. In addition, the special signal light emitter 200 is turned off during normal operation, which is the case of most train operations, and blinks only when there is a rare abnormality, so it blinks normally. Even if the driver makes a motion, there is a possibility that the driver pays attention to various other motions and accidentally misses it.

  On the other hand, in the special signal detection device 100 of the present embodiment, in consideration of the above circumstances, the special signal detection device 100 is strong against the external environment such as backlight and vibration, that is, has high robustness, and the special signal by the driver. The light emitting device 200 also has a configuration for suppressing an oversight of the operation of the light emitting device 200.

  Hereinafter, as a premise for explaining the special signal detection device 100 of the present embodiment, first, the structure and the like of the special signal light emitter 200 will be described with reference to FIG. 2. In this example, the special signal light emitting device 200 is provided near the railroad crossing, but in addition to this, the special signal light emitting device 200 is installed at various places where an abnormal situation may occur, such as a place where falling rocks may occur. Has been done.

  As shown in an example of the external appearance in FIG. 2, the special signal light emitting device 200 here has a structure in which a large number of linear LED light sources LS arranged on the front surface 200a are made to emit red light and blink, thereby making it possible to cross a railroad crossing or the like. Information such as abnormalities is transmitted to the driver. That is, the special signal light emitter 200 is installed beside the track so that the front surface 200a faces the special signal detection device 100 (see FIG. 1, etc.) arranged in the train TR.

  As an example of the blinking operation of the special signal light emitting device 200, it is assumed here that the blinking operation is performed about 500 times per minute. In other words, the frequency of the blinking operation of the special signal light emitter 200 is about 8.3 Hz. This frequency of 8.3 Hz can be considered to be a frequency peculiar to the special signal light emitting device 200 indicating the blinking operation of the special signal light emitting device 200. Hereinafter, this frequency of 8.3 Hz will be referred to as the spontaneous flashing frequency. The flashing operation as described above is common to all the special signal light emitting devices 200. That is, when there are two or more special signal light emitters 200, each of the special signal light emitters 200 blinks with the frequency of 8.3 Hz as the spontaneous blink frequency.

  As described above, the special signal light emitter 200 blinks the red light, that is, the light of the specific frequency band, at a certain specific cycle as an operation for notifying the occurrence of the abnormality. Therefore, in the present embodiment, attention is paid to the fact that the light emission operation of the special signal light emitter 200 is a blinking operation with light of a predetermined wavelength band in the above-described predetermined cycle, and the image capturing unit of the special signal detection device 100. The red component is extracted from the image data acquired in step 10, and the red lighting is detected from the difference between the current frame and the previous frame with respect to the frames forming each frame of the continuous moving image. That is, in the acquired image data, when it is detected that the red light is lit for a certain frame period, the special signal detection device 100 determines that the special signal light emitting device 200 emits light, and the sound unit that is the speaker. I am trying to sound an alarm from 30. Further, as will be described later in detail with reference to FIG. 4 and the like, in image processing in the special signal detection device 100, target image data is divided into image regions, and a partial image (hereinafter referred to as a partial image) including a plurality of divided frames is divided. , Also referred to simply as a continuous partial image.), The processing relating to the frequency of the above-mentioned blinking operation, that is, the frequency regarding the change in luminance is performed.

  Further, as the method of detecting the blinking cycle of the special signal light emitter 200 as described above, Fourier transform is used here. The Fourier transform here is a method of converting the time-series data acquired by the image capturing unit 10 into a size for each frequency component, and for example, the brightness of the entire continuous partial image extracted from the continuous image acquired by the image capturing unit 10. On the other hand, by performing the Fourier transform for each of a plurality of frames, the blinking period in the special signal light emitting device 200 can be detected. In other words, by performing the Fourier transform processing, the cycle or frequency of the blinking operation of the special signal light emitter 200 is captured, and the operation of the special signal light emitter 200 can be reliably detected. In other words, when the frequency characteristic relating to the luminance in each partial image is extracted by performing the Fourier transform process on the continuous partial images, the blinking operation of the special signal light emitting device 200 depends on whether or not the idiosyncratic blinking frequency exists. It is determined whether light is emitted.

  Further, as a result of the above analysis, when it is determined that the special signal light emitting device 200 emits light that blinks, the notifying unit IP notifies. That is, the special signal detection device 100 side can notify the driver by a method other than the transmission by the special signal light emitter 200.

  Hereinafter, with reference to the block diagram of FIG. 3, the configuration of the special signal detection device 100 and the functions of the respective parts constituting the special signal detection device 100 will be described.

  As illustrated, and as described above with reference to FIG. 1, the special signal detection device 100 includes the imaging unit 10, the management device MC, and the notification unit IP. Of these, the management device MC includes, as shown in the figure, an image processing unit 20 that performs various image processes, a storage device 50 that stores various data, and a control unit 60 that controls the operation of each unit. The notification unit IP includes the audio unit 30 and the display unit 40 as illustrated and as described above.

  In the special signal detection device 100, first, the imaging unit 10 is configured by a camera or the like, is capable of capturing a moving image, that is, a continuous image, and transmits the image data acquired by the imaging to the management device MC. As the continuous image here, for example, a moving image can be recorded at about 30 fps. Therefore, regarding the light emitting operation of the special signal light emitting device 200 that blinks at about 8.3 Hz, one blinking operation is captured in about several frames.

  Next, in the management device MC, the image processing unit 20 is configured by, for example, a GPU or the like, and performs various types of processing on the continuous image acquired by the imaging unit 10. In particular, here, the image processing unit 20 has an image division processing unit 20d that divides the continuous image acquired by the imaging unit 10 into a plurality of image regions to create a plurality of partial images. The image division processing unit 20d divides the continuous image composed of the plurality of frames GI acquired by the imaging unit 10 into four regions 1 to 4, and each of the plurality of frames GId, as conceptually illustrated in FIG. 4 partial images (continuous partial images) 1 to 4 are created. Returning to FIG. 3, the image processing unit 20 further performs Fourier transform processing, more specifically, on the continuous frames GId (see FIG. 4), that is, the image data arranged in time series, according to an instruction from the control unit 60 described later. Specifically, a fast Fourier transform (FFT) process is performed. Thereby, the amplitude data with respect to the frequency of the luminance in each continuous partial image is extracted. This makes it possible to detect whether or not there is a change in luminance at a frequency corresponding to the blinking operation of the special signal light emitter 200 described above.

  Next, in the management device MC, the storage device 50 is configured by a storage device or the like, for example, and stores various data and the like. That is, the storage device 50 functions as a recording device that stores various image data such as data acquired by the imaging unit 10 and data processed by the image processing unit 20, and also, for example, light emission in the special signal light emitting device 200. Stores various programs such as blinking cycle data (blinking frequency) data in step 1, and programs for performing fast Fourier transform (FFT) processing in the image processing unit 20. In addition, in the present embodiment, the data of the continuous partial image generated by the image division processing, which is one of the target data, is created by the image division processing unit 20d, and the data of the storage device 50 is stored. It is sequentially stored in the image storage unit 50d. In addition to this, for example, the storage device 50 stores the position of the special signal light emitting device 200 on the line, the position at which each of the special signal light emitting devices 200 can be visually recognized, and the image pickup of the image pickup unit 10 determined according to the position. Data or the like about the start position may be stored. That is, when the arrangement position of the special signal light emitting device 200 is grasped, it is conceivable that the operation start timing and the end timing of the special signal detecting device 100 are determined using these.

  Next, in the management device MC, the control unit 60 is configured by, for example, a CPU or the like, and integrally controls the operation of each unit configuring the special signal detection device 100. That is, necessary commands and data are appropriately read from the storage device 50 according to the processing, and various commands are issued. In addition, here, it functions as a determination unit that determines the presence or absence of light emission in the special signal light emitting device 200 that blinks at a predetermined cycle based on the extraction result by the fast Fourier transform (FFT) for image analysis in the image processing unit 20. To do. That is, the control unit 60 serves as a determination unit, based on the image data stored in the partial image storage unit 50d, for each partial image created by the image division processing unit 20d, whether or not the special signal light emitting device 200 emits light (especially Judgment of blinking operation).

  Next, of the notification unit IP, the voice unit 30 is configured by a speaker or the like. The voice unit 30 can notify the driver of the occurrence of abnormality by hearing, for example, by issuing an alarm with a volume that is sufficiently audible in the driver's seat. For normal driving, it is possible to make it easier to notice and reduce the possibility of being overlooked by notifying the driver who is performing various operations and checks by auditory abnormality occurrence.

  Finally, the display unit 40 of the notification unit IP is composed of a monitor or the like. The display unit 40 is arranged, for example, at a position where it is easily caught by the driver's eyes in the driver's seat to display characters and patterns, or various blinking / lighting displays, and display by light emission from the special signal light emitting device 200. Separately, it is possible to visually notify the driver of the occurrence of abnormality in the driver's seat.

  Hereinafter, the fast Fourier transform (FFT) for image analysis in the image processing unit 20 will be described with reference to FIG. FIG. 5A is a conceptual diagram of a continuous partial image to be processed by the image processing unit 20, and in the figure, a state in which each frame GId forming the continuous partial image is sequentially arranged in time series is conceptually illustrated. Is shown in. Here, a plurality of frames GId arranged in time series are extracted, and fast Fourier transform (FFT) is performed on these, so that the time series data is converted into a size for each frequency component.

  Further, FIG. 5B is a curve showing an example of data indicating the frequency related to the luminance obtained from the processing result by the image processing unit 20 for the plurality of frames GId which form the continuous partial image illustrated in FIG. 5A. (Polygonal line) The graph of C1 is shown. In FIG. 5B, the horizontal axis represents frequency and the vertical axis represents amplitude, that is, the degree of luminance change repeated at each frequency. As shown by the circle in the curve C1 in the figure, when a peak occurs at or near the spontaneous flashing frequency of 8.3 Hz, the luminance change at the frequency of 8.3 Hz, that is, in the special signal light emitting device 200 It can be understood that the blinking operation is occurring. Therefore, when a result such as the curve C1 of FIG. 5B is obtained, the control unit 60 as a determination unit determines that the special signal light emitting device 200 has a flashing operation, and according to the determination result. The notification unit IP is caused to perform an operation of notifying that an abnormality has occurred in the front. If the peak like the curve C1 does not occur, the control unit 60 determines that the special signal light emitting device 200 does not emit light. Note that even if a signal that causes a periodic blinking operation other than the light emission in the special signal light emitter 200, such as a crossing alarm, is also captured in the image, the above-mentioned special blinking frequency , Blinks at different frequencies, and therefore does not produce a peak corresponding to the spontaneous blinking frequency.

  In the above, the number of frames required for enabling the processing by the fast Fourier transform (FFT) with respect to a plurality of frames forming the continuous partial image is determined by the relationship between the spontaneous flashing frequency and the frame rate. As in the above example, when the spontaneous flashing frequency is about 8.3 Hz (blinking about 500 times per minute), and moving image capturing by the image capturing unit 10 is processed at a frame rate of about 30 fps, Assuming that the minimum number of blinks (blinking cycle) of the special signal light emitting device 200 required to perform one data acquisition as shown in (B) is about 2 to 3 times, image data for several frames to ten and several frames is obtained. Will be needed. That is, the data required for the determination can be obtained by performing the fast Fourier transform (FFT) on the frame GId for several frames to ten and more frames. Generally, in the imaging unit 10, the larger the frame rate number, that is, the finer the movement, the more detailed the luminance change can be captured, but from the above consideration, the spontaneous flashing frequency is about 8.3 Hz ( If the image capturing unit 10 has a moving image capturing capability of about 30 fps, it can be said that sufficient data can be obtained if the image capturing unit 10 has a moving image capturing capability of about 30 fps.

  Here, when the special signal light emitters 200 are detected, as shown conceptually in FIG. 6A, for example, a plurality of special signal light emitters 200 (i.e. It is possible that B) is present. Such a situation may occur, for example, when two or more railroad crossings CR are present close to each other on a straight line or on a curved line that is difficult to see ahead, as illustrated in FIGS. 6 (B) and 6 (C). In some cases, a plurality of special signal light emitting devices 200 are installed in advance.

  In the above case, if it is attempted to detect the blinking operation of the special signal light emitting device 200 using the spontaneous blinking frequency by the processing by the fast Fourier transform (FFT) for the entire continuous image, for example, When each of B and B operates, the change in brightness may be difficult to be captured or may not be captured depending on how the blinking cycle shifts between the spontaneous occurrence A and the specific occurrence B. Spontaneous A and Spontaneous B emit light having the same wavelength band characteristic at the same spontaneous flashing frequency. Therefore, on the special signal detection device 100 side, it is not possible to distinguish which component is derived, that is, in the above case, the special signal detection device 100 determines that the component originated from idiosyncratic A and idiosyncratic B. Only the blinking action of light combined with the derived components can be captured. Therefore, in particular, in the case of blinking at a timing at which the spontaneity A and the spontaneity B are reversed, there is a possibility that it may not be possible to catch this even if the blinking operation is performed. On the other hand, in the present embodiment, it is possible to avoid such a situation as much as possible by performing various types of processing on a continuous partial image obtained by dividing the continuous image into image regions instead of the entire continuous image.

  Hereinafter, first, with reference to the graphs of FIGS. 7A to 7C, etc., when two special signal light emitters 200 (spontaneous A and special B) are present and these flash and operate, A change in the blinking cycle as a whole due to a change in the degree of deviation of the cycle between A and the spontaneous event B will be described.

  First, FIG. 7 (A) conceptually shows a state of a cycle deviation when there is no deviation in the blinking cycle between the two spontaneous cases A and B. The horizontal axis of the graph represents time, and the vertical axis represents lighting / extinction. Above this, a curve QA1 indicated by a solid line in the figure shows the lighting and blinking timing of the spontaneous event A, that is, the blinking cycle of the spontaneous event A. Similarly, a curved line QB1 indicated by a broken line shows the state of the blinking cycle of the spontaneous event B. A curve QC1 shows the state of the blinking cycle in which the operations of the special event A and the special event B are combined. In this case, the blinking cycle indicated by the curve QC1 coincides with the blinking cycles of the special event A and the special event B. Therefore, even if the image is not divided and the whole image is processed by the above-mentioned fast Fourier transform or the like for detection, the blinking cycle indicated by the curve QC1 is captured, and as a result, the blinking operation is captured. be able to. However, the existence of the two special signal light emitters 200 (spontaneous A and special B) is not always captured.

  On the other hand, for example, in FIG. 7 (B), when the blinking cycle of idiosyncratic A and the blinking cycle of idiosyncratic B are deviated by 1/4 cycle, as shown by curves QA1 and QB1, the curve QC1 is shown. As described above, a difference occurs between the lighting time and the extinguishing time, and it becomes difficult to capture the change in brightness. That is, as compared with the case of FIG. 7A, it becomes difficult to capture the peak value using the spontaneous blinking frequency, and for example, the level value (FFT level) detected in the processing by the fast Fourier transform (FFT) becomes low. It is thought that it will appear by that. In particular, as shown by curves QA1 and QB1 in FIG. 7 (C), the blinking cycle of idiosyncratic A and the blinking cycle of idiosyncratic B are shifted by 1/2 cycle, and the timings of lighting and extinguishing are idiosyncratic A and idiosyncratic B. If and are reversed, it means that either one is always lit. That is, in the combination of these, the emission brightness is made uniform as shown by the curve QC1, and the blinking operation is not exhibited.

  Hereinafter, the difference in extraction of the amplitude data due to the deviation of the cycle between the two blinking special signal light emitters 200 (spontaneous A and special B) will be conceptually described with reference to the graph of FIG. 8. In FIG. 8, the horizontal axis represents the period shift between the sporadic A and the sporadic B, and the vertical axis represents the FFT level detected in the processing by the fast Fourier transform (FFT). Further, the maximum FFT level detected for one special signal light emitter 200 is set to 100%. In FIG. 8, a change in the FFT level detected with the deviation of the cycle between the two sporadic cases A and B in the above case is shown as a curve QQ. It is known that the curve QQ is a sine curve (cosine). Therefore, as illustrated in FIG. 7A, in the case where there is no cycle difference between the two sporadic cases A and B, the maximum FFT level is 200%, but the two special signal light emitters 200 blink. As the operation shift approaches 1/2 cycle, it becomes more difficult to catch the blinking operation. It should be noted that if it deviates by 1/4 cycle or more, it is considered that detection becomes difficult.

  On the other hand, in the present embodiment, as described above, a continuous partial image is created by dividing the continuous image into image regions, and then the continuous partial images are analyzed. For example, as shown in FIG. 9A, the entire continuous image is divided into four regions 1 to 4. In this case, for example, as shown in FIG. 9 (B) corresponding to FIG. 6 (A), two special signal light emitters 200, i.e., special occurrence A and special occurrence B, can be captured in different image areas. Specifically, in the case shown in the figure, by performing processing on the continuous partial image corresponding to the area 1, the peak value or the like caused by the spontaneous phenomenon A is extracted, and by performing processing on the continuous partial image corresponding to the area 4. It is considered that the peak value and the like due to the spontaneous phenomenon B are extracted. On the other hand, in the areas 2 and 3, it is considered that the blinking operation is not detected.

  Note that, in the above illustration, for the sake of explanation, the sporadic A and the sporadic B are drawn as if they are within the region 1 or the region 4 as an in-focus image, but in reality, they are composed of a camera or the like. Due to the condensing ability of the imaging unit 10 and the like, the component light caused by the sporadic A and the sporadic B is not irradiated only on the light receiving elements corresponding to the regions 1 and 4, but the light receiving elements corresponding to other regions. Can also be received. However, for example, it is considered that the component light of idiopathic A captured in the region 1 is overwhelmingly larger than the component light of idiosyncratic A captured in other regions, while the component light of idiosyncratic B is overwhelmingly small. Therefore, as a result extracted by the above-mentioned various processes, the motion of idiopathic A is captured in the area 1 and the motion of idiosyncratic B is captured in the area 4, as described above. That is, it is possible to accurately grasp each blinking operation by the two spontaneous events A and B.

  Hereinafter, an example of the operation of the special signal detection device 100 will be described with reference to the flowchart of FIG. 10. Here, as described above, the four regions 1 to 4 divided by the image division processing unit 20d of the special signal detection device 100 are sequentially processed.

  Specifically, first, the control unit 60 of the special signal detection device 100 reads the image of the region 1 (region number N = 1) from the partial image storage unit 50d (step S101), and image-processes the image of the region 1. It is input to the unit 20 (step S102), the brightness of the entire area is calculated (step S103), and the blinking cycle in the area is detected (step S104). When the spontaneous flashing frequency (frequency 8.3 Hz), which is the frequency component of the special signal light emitter 200, is detected from the detection in step S104 or more (step S105: Yes), the special signal light emitter 200 of the special signal light emitter 200 is detected. When it is determined that the motion is detected, the control unit 60, as the management device MC, notifies the driver by the notification unit IP to call attention (step S106). After the process of step S106, or when the spontaneous flashing frequency (frequency 8.3 Hz) is not detected at or above the threshold value in step S105 (step S105: No), the control unit 60 determines that the continuous partial image to be processed It is determined that the special signal light emitting device 200 does not exist (is not displayed), or if the special signal light emitting device 200 exists, it is in the extinguished light (turned off) state, and the process for the next region is performed without performing any special process thereafter. The value of the area number N is increased to move to (step S107), and it is confirmed whether the processing has been completed for all areas, that is, four areas (step S108). When it is determined in step S108 that the processing is not completed (step S108: No), the control unit 60 performs the processing operation from step S102 on the next area and determines that the processing is completed. In the case (step S108: Yes), a series of processing operations is ended.

  As described above, in the special signal detection device 100 according to the present embodiment, by extracting the amplitude data with respect to the frequency of the luminance of the continuous image acquired by the image capturing unit 10, the special signal in the captured image is extracted. It is possible to accurately grasp whether or not the light emitting device 200 includes a light emitting operation that blinks at a predetermined cycle. In this case, since the judgment based on the frequency can absorb the influence of the backlight, the shaking of the image, and the like at the time of image capturing, it can be made highly robust against the external environment. Further, in this case, the processing target in the image processing unit 20 is a partial image (continuous partial image) formed of a plurality of frames GId obtained by dividing a continuous image into image regions, so that, for example, two blinking different half cycles. In such a case that the special signal light emitters 200 (spontaneous A, special accident B) are imaged at once and the blinking operations of the respective special signal light emitters (spontaneous A, special accident B) are cancelled. Also, in either of the continuous partial images, only one of the special event A and the special event B can be captured, and more reliable light emission detection of the special signal light emitter 200 can be performed. Further, in this case, for the special signal light emitter 200 to be imaged by the image pickup unit 10, for example, it is not necessary to attach an infrared light emitter or to provide a structure for detecting disconnection, and a simple configuration The desired detection can be performed.

  In the above, the special signal detection device 100 provided in the train TR illustrated in FIG. 1 may always acquire an image, divide the image, and perform a necessary detection operation. The start timing and the end timing may be set appropriately. Here, as an example, a method of determining the start timing and the end timing of the operation by utilizing that the installation position of the special signal light emitting device 200 is predetermined will be described.

  First, as a premise, the installation position of a single or a plurality of special signal light emitting devices 200 installed on a railroad crossing along the line RR illustrated in FIG. It is also known that the driver can visually recognize the position of each special signal light emitter 200 associated with the information and the installation position. For example, necessary information is stored in the storage device 50 and can be called by the control unit 60. And Further, along with this, it is assumed that the range on the line RR that needs to be detected by the special signal detection device 100 is also predetermined. Here, as illustrated in FIG. 1, the driver can visually recognize each special signal light emitting device 200 (a predetermined position 600 m to 800 m before each special signal light emitting device 200), and a detection start position before AA ( It is assumed that the special signal detection device 100 starts detection from a predetermined position (XX) about 1 km before each special signal light emission device 200 and the special signal detection device 100 performs detection up to the installation position BB of the special signal light emission device 200. That is, the position XX is set as the start position of the detection by the special signal detection device 100, and the installation position BB of the special signal light emitter 200 is set as the end position of the detection by the special signal detection device 100, and the section DD (section of about 1 km) in between. Is a range on the line RR where the special signal light emitter 200 needs to be detected.

  Further, here, it is assumed that the information on the traveling position of the train TR can be acquired by, for example, an on-vehicle device (not shown). As a method of position information, various known position detection methods such as position detection using a tachometer can be used. That is, the special signal detection device 100 can receive information about the traveling position of the train TR from the train TR side, for example.

  By setting as described above, the start timing and the end timing of the detection operation by the special signal detection device 100 can be appropriately determined according to the passage position as the train TR moves.

[Second Embodiment]
Hereinafter, an example of the special signal detection device according to the second embodiment will be described with reference to FIG. 11. The special signal detection device according to the present embodiment is a modification of the special signal detection device 100 of the first embodiment, and in the management device MC, an internal processing mechanism such as various image processing in the image processing unit 20 is provided. Except for this, it is the same as the case of the first embodiment, and since it is common to the one illustrated in FIG. 3 and the like, the constituent elements will be appropriately referred to as necessary, and detailed description will be omitted.

  FIG. 11 is a conceptual diagram showing an example of image processing in the special signal detection device 100 according to the present embodiment, and is a diagram corresponding to FIG. 4 referred to in the first embodiment. In the present embodiment, the management device MC also detects the blinking operation of the special signal light emitting device 200 for a continuous image composed of the entire image before division. However, as described above, when the continuous image composed of the whole image before the division is analyzed by the processing such as the FFT, the degree of the shift of the operation timing between the plurality of special signal light emitting devices 200 (the blinking cycle There is a possibility that accurate detection may not be possible due to the degree of deviation. Therefore, in the present embodiment, as shown in the figure, first, it is possible that accurate analysis cannot be performed by performing analysis on a continuous image composed of whole images before division composed of a plurality of frames GI. If it has occurred, a division process is performed to create a partial image (continuous partial image) composed of a plurality of frames GId, and the created continuous partial image is an analysis target for determining detection of a blinking operation. Has become.

  An example of the operation of the special signal detection device according to this embodiment will be described below with reference to the flowchart in FIG. Here, as described above, the special signal detection device first performs various processes on the entire image acquired by the imaging unit 10, that is, on the plurality of frames GI in FIG. 11, prior to the division process. The blinking cycle in the entire area is detected, and the detection based on the division processing is performed as necessary.

  Specifically, first, when the control unit 60 of the special signal detection device 100 acquires a continuous image (entire image) composed of a plurality of frames GI captured by the image capturing unit 10 (step S201), the image By performing the fast Fourier transform (FFT) processing by the processing unit 20, the brightness of the entire area is calculated (step S202), and the blinking cycle in the entire area is detected (step S203). That is, when the special signal light emitting device 200 is reflected in the entire image, it is detected whether or not the special signal light emitting device 200 is performing the light emitting operation (blinking operation).

  If the spontaneous flashing frequency (frequency 8.3 Hz), which is the frequency component of the special signal light emitter 200, is detected from the detection in step S203 (for example, a predetermined threshold or more is detected) (step S203: Yes), the special When it is determined that the blinking operation of the signal light emitter 200 is detected, the control unit 60, as the management device MC, notifies the driver by the notification unit IP to call attention (step S204), and the special signal light emitter. A series of processing relating to the detection of 200 is ended.

  On the other hand, in step S203, when the spontaneous flashing frequency (frequency 8.3 Hz) is not detected (for example, not detected above the threshold) (step S203: No), the control unit 60 further detects light in the specific wavelength band. It is determined whether or not (step S205). That is, it is confirmed whether or not the light in the wavelength band of the red light used in the special signal light emitter 200 is detected in a predetermined threshold value or more in each frame GI or in a continuous image in which the frames are collected.

  In step S205, when the light of the specific wavelength band is not detected (step S205: No), the control unit 60 does not include the special signal light emitter 200 in the image (is not displayed), or even if it exists. It is determined that the light is off (turned off) (step S206), and the series of processes regarding the detection of the special signal light emitter 200 is ended.

  On the other hand, when the light in the specific wavelength band is detected in step S205 (step S205: Yes), the control unit 60 determines the special signal light emitting device from the wavelength band characteristic of the light as the determination result based on the entire continuous image described above. The special signal detection device 100 determines that 200 may be in the lighting state and that the blinking state may not be detected, and the special signal detection device 100 causes the image division processing unit 20d to create a plurality of partial images (step). S207). Here, among the partial images created in step S207, in the case where the light in the specific wavelength band is not detected, it is in a region where the special signal light emitter 200 is not included or the special signal light emitter 200 is in the off state. It is determined that the image is a partial image of a certain area, and the subsequent processing is removed as unnecessary, that is, it is excluded from the processing target (step S208). Thereafter, the image processing unit 20 performs a fast Fourier transform (FFT) process on the partial image to be processed to calculate the luminance of the region (step S209), and further, the blinking cycle in the region is determined. It is detected (step S210). That is, it is detected whether the special signal light emitting device 200 shown in each partial image is emitting light (flashing).

  When the spontaneous flashing frequency, which is the frequency component of the special signal light emitter 200, is detected from the detection in step S210 (step S210: Yes), the control unit 60 alerts the driver by alerting (step S204). Then, a series of processes regarding the detection of the special signal light emitter 200 is ended.

  On the other hand, when the spontaneous flashing frequency is not detected in step S210 (step S210: No), the control unit 60 confirms whether or not the dividing process is performed a predetermined number of times or more (step S211).

  When it is determined in step S211 that the number of times has not reached the predetermined number (step S211: No), the control unit 60 performs the division process from step S207. At this time, the division method may be changed and the special signal light emitter 200 may be detected by a new division.

  On the other hand, when it is determined in step S211 that the number of times has reached the predetermined number (step S211: Yes), the control unit 60 ends the series of processes regarding the detection of the special signal light emitter 200. In this case, that is, in the case where the blinking operation of the special signal light emitting device 200 is not detected although the light in the specific red light wavelength band is detected, the special signal light emitting device 200 is It is conceivable that the image pickup unit 10 captures light that originates from something other than the special signal light emitter 200 that includes a specific red light wavelength band component to be generated.

  When the series of processing shown in each of the above steps is completed, the special signal detection device 100 starts the above operation for the next acquired image data, and repeats the above operation until the light emission detection of the special signal light emitter is no longer necessary. .

  As described above, even in the special signal detection device according to the present embodiment, the special signal is determined not by the images themselves but by the frequency of the luminance indicating the characteristic of the blinking state extracted from the continuous images. It is possible to absorb the effects of back light and image shake when the light emitting device takes an image, and to make it highly robust against the external environment. On the other hand, if the required results cannot be obtained by analyzing the entire continuous image, the continuous partial image obtained by dividing the continuous image into image regions can be used as the analysis target for the determination. Even if two special signal light emitters that blink in different cycles are imaged at the same time and the blinking operations of the special signal light emitters cancel each other out, one of the continuous partial images is displayed. In, it is possible to capture only one of the two special signal light emitting devices, and more reliable light emission detection of the special signal light emitting device can be performed.

[Third Embodiment]
Hereinafter, an example of the special signal detection device according to the third embodiment will be described with reference to FIG. 13 and the like. The special signal detection device according to the present embodiment is a modification of the special signal detection device 100 according to the first embodiment, and the case of the first embodiment and the like except for the method of image division in the image division processing unit 20d. Therefore, regarding the constituent elements, other drawings will be appropriately referred to as necessary, and detailed description thereof will be omitted.

  FIG. 13A is a conceptual diagram showing an example of image division processing in the image processing in the special signal detection device 100 according to the present embodiment. For example, in the first embodiment, as the division into the four areas 1 to 4, the division into four rectangular areas of 2 × 2 in the vertical and horizontal directions as shown as a division pattern PT1 in FIG. 13 is adopted. The division method is not limited to this, and various modes can be considered. For example, as shown in the division pattern PT2, it is conceivable that the entire rectangular area is divided into four triangular areas divided by two diagonal lines into areas 1 to 4. Further, as shown in the division pattern PT3 and the division pattern PT4, the long regions divided in the vertical direction or the horizontal direction may be arranged in a line. Further, it is also possible to give variations to the way of division by sequentially changing these division patterns as shown by arrows AR1 to AR4. For example, in the second embodiment, it is conceivable to combine the above-described patterns as the predetermined number of division patterns in step S211 in the flowchart of FIG. That is, the extraction method of the partial image can be changed according to the determination result of the control unit 60 which is the determination unit.

  The area occupied by the special signal light emitting device 200 displayed in the image capturing unit 10 in the image can be considered to be different depending on the installation environment, as illustrated in FIGS. 6B and 6C. Furthermore, the imaging situation changes momentarily as the train runs. Therefore, when two or more special signal light emitters 200 appear, it is not always possible to unconditionally specify what kind of division pattern is most suitable for classifying them. Therefore, the reliability of detection is enhanced by preparing various division patterns.

  It should be noted that in the above, each of the four divisions is illustrated as an example, but the present invention is not limited to this. For example, division patterns PTα and PTβ shown in FIG. 13B and FIG. May be Furthermore, it is also possible to divide into other numbers. Further, as shown by hatching in FIG. 14, each of the divided regions 1 to 4 may be a partially overlapped region in the original entire image. Furthermore, in other words, the partial image may be cut out to create a partial image.

  As described above, also in the special signal detection device according to the present embodiment, a continuous partial image obtained by dividing a continuous image into image areas is an analysis target for determination, and the division pattern is changed as necessary. As a result, even if, for example, two special signal light emitters that blink for different half cycles are imaged at once and the blinking operations of the special signal light emitters cancel each other out, In either of the partial images, only one of the two special signal light emitters can be captured, and more reliable light emission detection of the special signal light emitter can be performed.

[Other]
The present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the scope of the invention.

  First, in each of the above-described aspects, it may be determined whether or not to change the extraction method of the partial image, depending on the change over time regarding the extraction result of the amplitude data. 15 (A) to 15 (C) are graphs for conceptually explaining a difference in change over time regarding operation detection of the special signal light emitter 200. In each figure, the horizontal axis of the graph represents the passage of time, which represents the distance from the special signal detection device 100 mounted on the traveling train to the special signal light emitter 200 fixedly installed. Equivalent to showing a change (approaching gradually). On the other hand, the vertical axis of the graph shows the FFT level detected by the special signal detection device 100.

  Of these, FIG. 15A conceptually shows a typical example of the extraction result of the amplitude data when the special signal detection device 100 detects the blinking operation of one special signal light emitter 200. It is a thing. That is, in the illustrated case, the distance from the special signal detection device 100 to the special signal light emitter 200 is reduced with the passage of time, so that the FFT level is gradually increasing and is a rising line (curve or straight line) CC1. .

  On the other hand, in actual measurement, it is considered that the line CC2 shown in FIG. That is, the FFT level temporarily decreases as compared with the line CC1 indicated by the broken line, but after a while, it may be possible to return to the same state as in the case of FIG. This is considered to occur when, for example, a utility pole, a tree, or the like existing near the line is shaded and the brightness temporarily changes. In such a case, it is considered that the blinking operation in one special signal light emitting device 200 is captured, as in the case of FIG.

  On the other hand, for example, the line CC3 shown in FIG. That is, in FIG. 15 (C), the FFT level decreases as in the case of FIG. 15 (B), but thereafter, even if time elapses, the state equivalent to the case shown by the line CC1 cannot be restored. . In such a case, unlike the case of FIG. 15 (A) or FIG. 15 (B), two or more special signal light emitters 200 are projected at the time when the FFT level is lowered, and the interference between them causes the amplitude. It is considered that the extraction result of data may be affected.

  In consideration of the above situation, for example, when the tendency illustrated in FIG. 15C is seen, the operation detection of the special signal light emitting device 200 based on the divided image shown in each of the above modes It is conceivable that even if the operation detection of the plurality of special signal light emitting devices 200 occurs, it is possible to surely catch the operation detection.

  The items described in each of the above-described embodiments may be appropriately combined and configured.

  Moreover, although the case where the special signal detecting device 100 is mounted on a railroad train as a moving body on a track as a dedicated travel path has been described above, the present invention is not limited to this, and for example, a track as a dedicated travel path ( For a tram that is a vehicle (moving body) traveling on a new track or a combined track, or a bus that is a vehicle that travels on a dedicated road as a dedicated travel route, a special signal light emitting device 200 provided beside the dedicated road On the other hand, it is also possible to provide the special signal detection device 100.

  When a camera such as a train is provided for various kinds of detection such as detection of the presence or absence of an obstacle, the camera may be used as the imaging unit 10. That is, the light emission detection by the special signal light emitting device 200 according to the configuration of the present application may be performed using the image information acquired by the camera provided for various detections. For example, of the data captured by the obstacle detection camera, only the image data in the detection target section by the special signal detection device 100 may be used. Further, although the image pickup unit 10 is a camera, various types can be applied as long as it can receive light necessary for data extraction, and it may be considered that the image pickup unit 10 is composed of only a light receiving element without a lens. To be Further, in the above, the wavelength filter FI is provided on the front surface side of the imaging unit 10, but the position of the wavelength filter FI may be other than the front surface, and the wavelength filter FI may be provided at another position on the optical path in the imaging unit 10. Good. Further, the light receiving characteristic of the light receiving element in the imaging unit 10 may be made to correspond to the characteristic of the light from the special signal light emitting device 200.

  Further, for example, each part of the special signal detection device 100, which is partially enlarged and illustrated in FIG. You may be able to attach.

  10 ... Imaging unit, 20 ... Image processing unit, 20d ... Image division processing unit, 30 ... Audio unit, 40 ... Display unit, 50 ... Storage device, 50d ... Partial image storage unit, 60 ... Control unit, 100 ... Special signal detection Device, 200 ... Special signal light emitter, 200a ... Front surface, A, B ... Special (special signal light emitter), A1 ... Arrows, AA ... Predetermined position, AR1 to AR4 ... Arrows, BB ... Installation position, C1 ... Curve, CC1 -CC3 ... Line, CR ... Railroad crossing, DD ... Section, EB ... Emergency button, FI ... Wavelength filter, GI ... Frame, GId ... Frame, IP ... Notification section, LS ... LED light source, MC ... Management device, PT1 to PT4. PTα, PTβ ... Division pattern, QA1, QB1, QC1 ... Curve, QQ ... Curve, RR ... Line, SG ... Special signal generation system, TR ... Train, VE ... Vehicle, XX ... Position

Claims (13)

An imaging unit that captures continuous images,
An image processing unit that extracts amplitude data with respect to a frequency of luminance, with respect to a partial image composed of a plurality of frames obtained by dividing the continuous image into image regions.
A special signal detection device, comprising: a determination unit that determines whether or not the special signal light emitting device blinks at a predetermined cycle based on the extraction result of the partial image.   The special signal detection device according to claim 1, wherein the image processing unit performs Fourier transform processing on the entire partial image to extract data.   The image processing unit has an image division processing unit that divides the continuous image into a plurality of image regions to create a plurality of the partial images, and amplitude data for each of the partial images created by the image division processing unit. The special signal detection device according to claim 1, wherein the special signal detection device extracts the signal.   The special signal detection device according to claim 3, wherein the determination unit determines whether or not the special signal light emitting device emits light for each of the partial images created by the image division processing unit.   The image processing unit, when it is determined that there is no blinking in the special signal light emitting device in the determination result of the determination unit based on the entire continuous image, performs the plurality of partial images by the image division processing unit, The special signal detection device according to any one of claims 3 and 4.   The image processing unit, in the determination result of the determination unit based on the entire continuous image, when the special signal light emitting device is in the lighting state from the wavelength band characteristic of light The special signal detection device according to claim 3, wherein a plurality of partial images are created by a division processing unit.   The image processing unit ends the creation of the partial image when it is not determined that the partial image is a blinking state even after performing a predetermined number of times of amplitude data extraction for the partial images created by the image division processing unit, The special signal detection device according to claim 6.   The image processing unit, among the plurality of partial images created by the image division processing unit, the partial image for which it is determined that the special signal light emitting device is in the off state in the determination result of the determination unit, The special signal detection device according to any one of claims 6 and 7, which does not require processing.   The special signal detection device according to any one of claims 1 to 8, wherein the image processing unit changes a method of extracting the partial image according to a determination result of the determination unit.   The special signal detection device according to claim 9, wherein the determination unit determines whether or not to change the extraction method of the partial image according to a temporal change regarding the extraction result of the amplitude data in the image processing unit. .   If the amplitude data having peaks at different timings is extracted in the one partial image and the other partial image in which different image regions are extracted, the determination unit determines that there are a plurality of special signal light emitters that emit light. The special signal detection device according to any one of claims 1 to 10, which makes a determination.   The special signal detection device according to any one of claims 1 to 11, further comprising: a notification unit that performs a notification when it is determined by the determination result of the determination unit that the special signal light emitter emits light.   The special signal detection device according to claim 12, wherein the notification unit is a voice unit that issues an alarm.

Images