JPH04185579A - Train number display image input device - Google Patents

Abstract

PURPOSE:To correctly image-pick up a train number display image by varying the shutter speed of a camera according to the train speed, and simultaneously compensating the shortage of light quantity due to a difference to image-pickup an image pick-up area. CONSTITUTION:An apparatus in the title comprises an irradiation device 40 for irradiating an image pick-up area 13 containing a train number display device 12 in front of a train 10 and an internal synchronous shutter camera 50 for image-pickuping the image pickup area 13. At the time of stopping a train at platform, the train speed differes with the train organizing number. In this case, at the station, train detecting sensors 20a, 21a are disposed in front and in rear, and a voltage indicated value for outputting the shutter speed for image-pickuping a train number display image without blurring and the light emitting quantity corresponding to the shutter speed is output from a control device 30. That is, the detecting time t of the train detecting sensors 20a, 21a is divided into four time regions, the shutter speed is set corresponding to the respective regions. On the other hand, the light emitting quantity for substantially uniforming the photo detecting sensitivity of the camera 50 is actually obtained to command a voltage value corresponding to the obtained light emitting quantity.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention provides a method for capturing and inputting images of peripheral imaging areas including a train number display attached to the front and rear sides of a train. The present invention relates to a train number display image input device.

(Prior Art) Conventionally, a device for reading the license plate number of a vehicle is known as a device that automatically images a moving object and captures an image signal.

This conventional display image input device, as shown in FIG.
When a car 101 enters between the car body detection light emitter 102a and the car body detection light receiver 102b, the presence of the car 101 is detected and the signal is transmitted to the power supply unit 103 and the camera 10.
4. Output to camera interface (1/F) 105. In response to this output signal, the irradiator 106 momentarily emits light, and when the camera 104 inputs an external trigger signal in synchronization with this instantaneous light emission, the electronic shutter is activated for a preset fixed value of 1/1000 seconds. The CCD element is opened to expose the CCD element, and the accumulated charge is converted into an electric signal and output to the camera interface 105.

The camera interface 105 inputs a video signal (electrical signal) from the camera 104, detects the beginning of one screen, performs D/A conversion for each pixel, and converts it into a digital signal.
The image information for one screen is written in the image memory 106 by sequentially outputting it to the image memory 106.

In addition, a vehicle body detection light emitter 102a and a vehicle body detection light receiver 10
In some cases, instead of 2b, a timer 107 generates a trigger signal at a cycle of 0.5 seconds and captures an image signal in the same manner as above.

(Problem to be Solved by the Invention) However, in such a conventional display image input device for reading a license plate number of a car, illumination with a constant illuminance is emitted instantaneously to the imaging area. Furthermore, since the camera used was a camera with a constant shutter speed of 1/1000 second electronic shutter, it could not be used to take an image of the train number display.

This is because in recent years, heat-absorbing glass has been used for the front and rear windows of trains in order to reduce the rise in indoor temperature caused by sunlight on the driver's seat. It absorbs light in the infrared wavelength range to warm the glass and prevent the temperature inside the driver's cabin from rising, so it shines infrared light on the area around the train number display through the front glass of the driver's seat. If you try to take an image, the infrared light will be absorbed by the heat-absorbing glass, resulting in a completely black image, making it impossible to distinguish the characters on the train number display.

Therefore, if we try to irradiate visible light without using infrared light, in order to obtain a clear captured image, we must irradiate strong visible light, and that light will cause the driver's and conductor's eyes to There was a problem that permission could not be obtained for its use because it could cause blinding and make it impossible to see anything for a while.

This invention was made in view of these conventional problems, and instead of emitting infrared rays, it irradiates as weak light as possible to avoid disturbing the eyes of the driver and conductor. It is an object of the present invention to provide a train number display image input device capable of capturing an image of a display.

[Structure of the Invention] (Means for Solving the Problems) The train number display image input device of the present invention is arranged at regular intervals along a track, and detects trains entering or leaving. detecting means; and when the train detecting means detects the entry or departure of the train, a signal is inputted to determine the time for the train to pass between these two train detecting means, and a preset time is set in accordance with the determined passing time. a shutter camera that receives the shutter speed selection signal from the control means and captures an image at the corresponding shutter speed; and a voltage output from the control means. Voltage generation means that inputs a value selection signal and generates a corresponding voltage; irradiation means that inputs the output voltage of the voltage generation means and emits light with an amount of light according to the voltage; and when the irradiation means emits light. and an image memory that captures and stores image information captured by the shutter camera of a peripheral imaging area including the train number display.

(Function) In the train number display image input device of the present invention, when a train advances on the track and passes the part of the train detection means, the train detection means detects the approach or separation of the train. The control means inputs a signal when the train detection means detects the entry or separation of the train, calculates the time for the train to pass between these two train detection means, and sets the control means in advance in accordance with the determined passing time. The selected shutter speed and voltage value type are output as selection signals.

The shutter camera receives a shutter speed selection signal from the control means and takes an image of the surrounding imaging area including the train number display attached to the front or rear of the train at the corresponding shutter speed. When taking an image with the shutter camera, upon receiving a voltage value selection signal from the control means, the voltage generation means generates a voltage of a corresponding strength and applies it to the irradiation means, and the irradiation means adjusts the voltage according to the applied voltage. The image capturing area is irradiated with visible light at a certain amount of light so that the image captured by the shutter camera becomes clear.

In this way, depending on the train's approach or departure speed, if the speed is fast, it is necessary to take an image with a fast shutter speed, so the amount of visible light irradiation is increased to take an image, and conversely, if the train is slow, the image needs to be taken with a high shutter speed. Because it is possible to capture images at a slow shutter speed, the amount of visible light irradiation is also weakened. A clear train number display image can be obtained.

(Example) Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, in which train detection sensors 20a and 21a are installed at regular intervals to detect when a train 10 is moving along a track 11. . Each of the train detection sensors 20a and 21a emits light and irradiates it to the light reflectors 20b and 21b installed on the opposite side of the track 11, and receives the reflected light again, so that the reflected light can be received. When detecting the entrance of a train by changing the state from being unable to receive reflected light to not being able to receive it, or detecting the separation of a train, detecting the passing of a train by changing from being unable to receive reflected light to being able to receive reflected light again. It looks like this.

The train number display image input device of this embodiment uses the signals Sl of these train detection sensors 20a and 21a.

A controller 30 for inputting S2, an irradiator 40 for illuminating the surrounding imaging area 13 including the train number display 12 attached to the front of the train 10, and an internal synchronizer for imaging the imaging area 13. (Once the shutter speed is set, images can be captured periodically at the same shutter speed) Shutter camera 50 and this camera 50
Camera interface (1/F
) 60, and an image memory 61 for storing image signals.

As shown in FIG. 2, the controller 30 includes a microprocessor (MPU) 31, a ROM 32, a RAM 33, an interrupt module (interrupt M) 34, and a clock module (clock M) 35 for time management. and a digital output module (digital output M) 36 for outputting digital signals P, C, and I.

Then, the MPU 31 takes out the program stored in the ROM 32 one step at a time, decodes it, and executes it. The interrupt module 34 detects the rising edge of the input pulse from the train detection sensors 20a, 21a and the clock module 35 and notifies the MPU 31 of the interrupt, and the MPU 31 takes out the program starting from the interrupt destination address from the ROM 32 and executes it.

The clock module 35 is a module that generates a pulse every second and outputs it to the interrupt module 34. Further, the RAM 3B temporarily stores data required during program processing and stores data during calculations.

Digital output module 36 outputs contact information or voltage signal C via relay 51 to give a shutter speed command to camera 50, and outputs contact information or voltage signal P to instruct voltage generator 41. , and further outputs the trigger signal (2) to the camera interface 60 as contact information and voltage.

The camera 50 adjusts the shutter speed to 1/1 according to the train speed.
It is possible to switch between four shutter speeds of 60.1/120.1/180.1/240 seconds, and this selection is made based on a command given from the controller 30 via the relay 51.

The irradiator 40 is provided with a voltage generator 41, and when one of four signals instructed according to the shutter speed is input from the controller 30, the voltage generator 41 changes the corresponding shutter speed. A preset voltage value is output to the irradiator 40 in order to obtain the amount of light emitted corresponding to It is designed to compensate for the decrease in light-receiving sensitivity due to

When the camera interface 60 receives the input timing of the imaging signal from the camera 50 from the controller 30, it detects the vertical synchronization signal of the camera 50, captures the imaging signal of the first pixel for one screen as an electrical signal, and /A conversion and sequentially convert all pixels one by one (256 dots horizontally x 256
This is an interface for sending the image to the image memory 61 (vertical dot). The image memory 61 stores 64 to 128 bits of information for one pixel (0 bit is black, b3 or 127 bits is white, 0 to 63 or O to 12 bits).
The area between 7 and 7 is a part where intermediate colors between black and white are stored as numerical values.

Next, the operation of the train number display image input device described above will be explained.

Based on Figure 3, to explain the relationship between the number of train formations and train detection speed, for three types of train formation numbers of 4 cars, 6 cars, and 8 cars, When the train stops, the train speed is 1 for an 8-car train.
The vehicle draws a curve of (speed-position) and comes to a stop with the front section located near point A. Similarly, for a 6-car train, the train speed is 11
The train stops near point B, and the train speed is 11 for a 4-car train.
1 and stop near the 0 point.

Therefore, now, the train detection sensors 20a, 21. When a is arranged as shown in Fig. 3, the average speed between the train detection sensors 20g, 21a for an 8-car train is V], and V2 and v3 for a 6-car and 4-car train, respectively. . In addition,
For a 4-car train, this is the average speed at the time of departure after stopping at 6 points.

In this way, since the average speed measured differs depending on the number of vehicles in the train, stopping position, and driving operation, measurements are performed between two points.

Then, in order to output a shutter speed that allows the train number display image to be captured without blurring based on the average speed measured in this way and a voltage instruction value that can output the amount of light emission corresponding to the shutter speed, the controller 30 is set as shown in FIG. Control data such as this is stored.

That is, the detection time Δ of the train detection sensors 20a and 21a
Divide t into time domains 1, 2, 3.4 and calculate the shutter speeds C(1), C(2), C(3), C(4)
respectively 1/240.1/180.1/120.1/
60 seconds, while voltages V(1), V(2),
The amount of light emitted by V (3) and V (4) at which the light receiving sensitivity of the camera 50 becomes almost constant is actually determined, and the voltage values Vl, V2°VB, and V4 corresponding to the amount of light emitted are commanded. There is.

Therefore, to explain the operation of the controller 30, the train 1
0 travels on the track 11 and approaches the mounting position of the train detection sensor 20a, the optical signal emitted from the train detection sensor 20a is reflected from the reflector 20b and does not return. As a result, the front part of the train 10 is connected to the train detection sensor 20a.
It is possible to detect that the vehicle has entered the position of , and input the detection signal S1 to the interrupt module 34 of the controller 30.

In response to this, the interrupt module 34 sets the interrupt destination address to interrupt, and the MP 31 analyzes the interrupt and
The execution address of the program is moved to the interrupt destination address B30 shown in the figure, and the program starting from block B500 is executed.

The program in block B500 ends by writing 0 to the memory address T that counts the clock pulses output by the clock module 35. here,
The clock pulses generated every second by the clock module 35 are executed via the interrupt module 34 to the execution address of the program starting from the clock interrupt block B40 (this processing operation will be described later), according to the flowchart shown in FIG.

Next, when the train 10 reaches the train detection sensor 21a,
The train detection sensor 21a outputs a train presence detection signal S2. This signal is input to the interrupt module 34 of the controller 30, and execution is shifted to program block B510 starting from the S2 interrupt processing start address B31.

Block B510 reads the content Δt of the clock storage address T counted up by a clock interrupt, which will be described later, and executes the next block B520.

Block B520 has a value of Δt in the time domain 1 to 1 in FIG.
Find which of 4 applies, and move to the next block B530.
Execute. In other words, if Δt is smaller than time t1, then 1
If it is between t1 and t2, it is set as 2, if it is between t2 and t3, it is set as 3, and if it is between t3 and t4, it is set as 4. Next, block 8330 extracts shutter speed C (n: 1, 2, 3.4) and voltage V from a previously stored shutter speed and voltage setting table (not shown).
(n: 1, 2, 3.4) is taken out to memory address C01vO and the next block B540 is executed.

Block B540 outputs 4 signals from the digital output module 36 to the relay 51 and voltage generator 41 in the front stage of the camera 50.
Go to the appropriate book! Output digital output signal (Do) signals P, C (contact signal or 9 voltage signal),
The next block B550 is executed.

In block B550, the time m seconds (this is called a delay time) until the irradiator 40 stably emits light is set in the memory address K, and this process is ended.

Next, based on the flowchart in FIG. 7, the processing program block B4O0 starting from the clock interrupt execution start address B40 adds 1 to the contents ((T)) of the memory address T storing the clock, and then Block B of
Execute 410.

In block B410, if the content at the memory address where the delay time is stored is 0, it remains O, but if it is not 0, it is subtracted by 1 and the next block B420 is executed.

If the content of the memory address is 0, the block B420 considers that the irradiator 40 has stably emitted light, and the block B420 selects the next block B430.
Execute 440.

Block 8430 outputs the bird signal I from the digital output module 36 to the camera interface 60 and ends the process. Block B440 also turns off the trigger signal through the output signal l of the digital output module 36, and ends this process.

In this way, when a train stops at a platform and departs after handling passengers, especially trains with different train sizes, in order to capture images of the surrounding area including the train number display with one camera, it is possible to stop or Images are taken using the low-speed driving area just before departure. This allows the train to be imaged while the train is moving, and the shutter speed to avoid blurring to be specified, and since the train is running at low speed, the shutter speed can be kept low. The negative impact of lighting on driving and conductor duties can be reduced.

On the other hand, since no infrared irradiator is used, clear images can be obtained using visible light even when heat-absorbing glass is used for the cab surface glass.

In addition, the shutter speed is variable according to the running speed of the train, and the minimum amount of illumination corresponding to each shutter speed is irradiated, so the captured image does not dazzle the eyes of the train crew. An image with a constant contrast can be obtained.

Furthermore, the system detects a running train and adjusts the light intensity and shutter speed according to the speed of the train to capture the image of the train number on the train number display, so the train number is displayed on the platform. A display image device can be installed, and there is no need to install cameras or other necessary equipment outside the platform, resulting in lower equipment costs.

[Effects of the Invention] As described above, according to the present invention, the shutter speed of the camera is made variable according to the slowness of the train speed, and at the same time, the insufficient amount of light due to the difference in shutter speed is compensated for by adjusting the amount of light emitted by the irradiation means. This method is used because it is necessary to irradiate the imaging area with a strong amount of visible light as in the conventional method, which would blind the crew's eyes. To enable a train number display image to be captured while irradiating a necessary and sufficient amount of visible light without always irradiating with a bright amount of light that dazzles the eyes of a train crew.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of a controller in the above embodiment, and FIG. 3 is an explanatory diagram illustrating the characteristics of the train detection sensor in the above embodiment.
FIG. 4 is an explanatory diagram showing the relationship between train speed, shutter speed, and light emission amount regulation voltage in the above embodiment, FIGS. 5 to 7 are flow charts showing the operation of the above embodiment, and FIG.
The figure is a block diagram of a conventional example. 10... Train 11... Track 12...
Train number display 13...imaging areas 20a, 21
a... Train detection sensor 30... Controller 40... Irradiator 41...
・Voltage generator 50...Camera 51...Relay 60...Camera interface 61...Image memory

Claims (1)

[Claims] Train detection means arranged at regular intervals along a track to detect when a train is approaching or leaving; a control means that inputs a signal to determine the time it takes for the train to pass between these two train detection means, and outputs a preset shutter speed and voltage value type as a selection signal corresponding to the determined passage time; a shutter camera that receives a shutter speed selection signal from the control means and captures an image at the corresponding shutter speed; a voltage generation means that receives a voltage value selection signal from the control means and generates a corresponding voltage; irradiation means that inputs the output voltage of the voltage generation means and emits light with an amount of light according to the voltage; and when the irradiation means emits light, the shutter camera images an imaging area in the periphery including the train number display. A train number display image input device comprising an image memory that captures and stores image information.