JP6369268B2 - Display unit state determination method, display unit state determination program, display unit state determination device, and display system - Google Patents

Description

  The present invention relates to a display unit state determination method, a display unit state determination program, a display unit state determination device, and a display system.

  Various information about roads such as traffic jam information and construction information is often notified to the driver of the vehicle by display on an information bulletin board installed on the road. In recent years, an electronic bulletin board using a light emitting diode (LED) is mainly used as an information bulletin board. Here, when characters or the like are displayed on the information bulletin board, it is preferable that important information is displayed in a color that the driver can easily recognize. For this reason, normally, information with low importance is displayed in green or orange characters, and road closure or accident information with high importance is displayed in red characters.

  Various methods for correcting visibility deterioration in an image display device are known (see, for example, Patent Documents 1 and 2).

JP 2003-228330 A JP 2008-107715 A

  For example, in the case of an information bulletin board on an expressway, visibility is reduced due to the influence of sunlight, weather, exhaust gas smog, yellow sand, etc., because it is installed in a harsh environment that operates 24 hours 365 days outdoors. Easy to do.

  However, conventionally, it has not been possible to correctly identify the cause of the deterioration of the visibility of the information bulletin board, that is, the state of the information bulletin board.

  In one aspect, the present invention provides a display unit state determination method, a display unit state determination program, a display unit state determination device, and a display system that can correctly determine the state of a display unit of an information bulletin board. Objective.

  In one aspect, the display state determination method uses a Cr value and a Cb value of the character or graphic color from the first RGB value that is the RGB value indicating the color of the character or graphic displayed on the display unit of the information bulletin board. The first Cr value and the first Cb value are calculated, the character or the figure is displayed on the display unit based on the first RGB value, and the display unit captures the display unit with the imaging device. A first Y value that is a Y value of the character or graphic in the image is calculated from a second RGB value that is an RGB value indicating the color of the character or graphic, and the first Y value and the first From the Cr value of 1 and the first Cb value, a third RGB value, which is an RGB value indicating the color of the character or figure, is calculated, and the display unit is configured to calculate the third RGB value based on the third RGB value. In front of an image in which characters or figures are displayed and the display unit is imaged by the imaging device A second Cr value and a second Cb value, which are Cr and Cb values of the character or graphic in the image, are calculated from a fourth RGB value that is an RGB value indicating the color of the character or graphic. A process for determining whether or not the display unit is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value. Is a display unit state determination method executed by.

  As one aspect, there is an effect that the state of the display unit of the information bulletin board can be correctly determined.

1 is a diagram schematically illustrating a configuration of a display system according to an embodiment. It is a figure which shows an example of system setting information. It is a figure which shows an example of an information bulletin board. It is a flowchart (the 1) which shows the process of a control apparatus. It is a flowchart (the 2) which shows the process of a control apparatus. It is a table | surface for demonstrating the case where a display part is dirty. It is a table | surface for demonstrating the case where LED of a display part has degraded.

  Hereinafter, an embodiment of a display system will be described in detail with reference to FIGS. FIG. 1 schematically shows a configuration of a display system 1 according to an embodiment.

  As shown in FIG. 1, the display system 1 controls a plurality of expressway information bulletin boards (hereinafter referred to as information bulletin boards) 2, an imaging device 3 that acquires images of the information bulletin boards 2, and display of the information bulletin boards 2. , A control device 4 as a display unit state determination device for executing processing for determining the state (normal, dirty, deteriorated, etc.) of the information bulletin board 2, and an information management device 5 for managing system setting information to be displayed on the information bulletin board 2. . Each of the information bulletin board 2, the imaging device 3, the control device 4, and the information management device 5 is connected to a network 6 such as the Internet.

  The information bulletin board 2 is installed at a predetermined position on the expressway, and displays system setting information such as traffic jam information, construction information, and accident information in characters and figures based on control information from the control device 4. As shown in FIG. 1, the information bulletin board 2 includes a communication unit 17, a display control unit 18, and a display unit 50. The communication unit 17 executes processing for receiving system setting information transmitted from the control device 4, processing for notifying the control device 4 that the system setting information has been correctly received, and the like. The display control unit 18 executes processing for causing the display unit 50 to display information based on the system setting information. The display unit 50 includes LEDs and the like, and displays characters and the like so as to be visible to the driver of the automobile under the instruction of the display control unit 18.

  For example, the same number of imaging devices 3 as the information bulletin boards 2 are prepared, and one imaging device 3 is installed at a position where the entire display unit 50 of one information bulletin board 2 can be imaged. The installation location of the imaging device 3 is a position where an image can be acquired in a state close to the line of sight or field of view when the driver views the system setting information displayed on the information bulletin board 2 (for example, a median strip on a highway) Can be adopted. As illustrated in FIG. 1, the imaging device 3 includes a communication unit 19 and an imaging unit 20. The communication unit 19 receives a signal requesting transmission of an image from the control device 4 or transmits an image obtained by capturing the information bulletin board 2 to the control device 4. The imaging unit 20 includes a lens, an imaging element, and the like, and executes processing for acquiring an image on the information bulletin board 2.

  The control device 4 includes a CPU (Central Processing Unit) 11, a RAM (Random Access Memory) 12, a storage device 13 such as an HDD (Hard Disk Drive), an input device 14 such as a mouse and a keyboard, an output device 15 such as a display, and information. And a communication device 16 that communicates with the bulletin board 2 and the like.

  Furthermore, the control device 4 can realize the characteristic functions of the present embodiment by causing a computer to execute a display control program for a bulletin board and a display state determination program. Specifically, the control device 4 includes a display control unit 21, a display state acquisition unit 22, a character color correction unit 23, and a correction value determination unit 24.

  The display control unit 21 creates system setting information including control character string information for specifying characters and graphics and control character color information for specifying a color when the control character string information is displayed on the information bulletin board 2. As the color information included in the system setting information, RGB values are used. When there are a plurality of information bulletin boards 2, information for specifying the information bulletin board 2 for displaying characters and the like is added. The system setting information can use the data transmitted from the information management apparatus 5 as it is.

  The display state acquisition unit 22 executes processing related to acquisition of a captured image of the information bulletin board 2 captured by the imaging device 3.

  The character color correction unit 23 corrects color information such as characters displayed on the information bulletin board 2 based on information included in the captured image acquired by the display state acquisition unit 22.

  The correction value determination unit 24 is based on the color information obtained by the display state acquisition unit 22 and the color information (system setting information) used by the display control unit 21 for control (state of the display unit 50 of the information bulletin board 2 ( Normal, dirt, LED deterioration, etc.). The correction value determination unit 24 causes the output device 15 to output (display, etc.) the determination result.

  Here, an example of system setting information, which is information displayed on the information bulletin board 2, will be described with reference to FIG. The system setting information includes a “bulletin board ID” assigned to each information bulletin board 2, a “block number” for specifying an area for displaying information on the information bulletin board 2, and a “control” for specifying a sentence or figure to be displayed. Each field includes a “character string” field and a “control character color” field for designating the color of the character string and graphic to be displayed. In FIG. 2, it is assumed that the display of one information bulletin board 2 is managed by one system setting information.

  For example, in the first line of the system setting information in FIG. 2, the control character string “Previous” is displayed in the area of the block number “1” of the display unit 50 of the information bulletin board 2 in which the bulletin board ID is set to “1”. It is shown that the color “R: 255, G: 255, B: 255” is displayed. In the second line of the system setting information, the control character string “construction traffic jam 3 km” is displayed in the area of the block number “2” of the display unit 50 of the same information bulletin board 2 and the control character color “R: 200, G: 200”. , B: 100 ”. Furthermore, the third line shows that the control character string “Caution for raining” is displayed in the control character color “R: 200, G: 200, B: 100” in the area of the block number “3”. ing. The control character color information is displayed as an RGB value, and the value stored here becomes the system setting information (first RGB value).

  FIG. 3 shows an example of the information bulletin board 2. As shown in FIG. 3, the display unit 50 of the information bulletin board 2 is provided with blocks 51 to 54 as an area in which an arbitrary character or figure can be displayed using a plurality of colors by LEDs, for example. Yes. Specifically, the blocks 51 to 54 are, as viewed from the driver, the first block 51 on the upper side and the left side, the second block 52 adjacent to the first block 51 on the upper side and the right side, and the first and first blocks. 3 includes a third block 53 disposed below the second block and a fourth block 54 located on the leftmost side. Each of the blocks 51 to 54 corresponds to the number specified by the block number information of the system setting information shown in FIG. For example, “1” in the block number information corresponds to the first block 51.

  In the example of FIG. 3, “the future” is displayed in the first block 51, “construction traffic jam 3 km” is displayed in the second block 52, and “rainy driving attention” is displayed in the third block 53. As a result, the display section 50 of the information bulletin board 2 displays the information “This pre-construction traffic jam 3 km rain caution” divided into two lines. In this case, “beyond” is displayed in the control character color “R: 255, G: 255, B: 255”, that is, white. On the other hand, “construction traffic jam 3 km” and “rain driving attention” are displayed in control character colors “R: 200, G: 200, B: 100”, that is, green.

  Returning to FIG. 1, for example, a server device is used as the information management device 5. The information management device 5 receives road traffic information from an external device (not shown), creates system setting information for each information bulletin board 2, and transmits the system setting information to the control device 4.

  Next, processing of the display system 1 will be described with reference to the flowcharts of FIGS. 4 and 5.

  In the flowchart of FIG. 4, first, in step S <b> 10, the control device 4 (display control unit 21) performs system setting information (first RGB value) for the information bulletin board 2 identified by the bulletin board ID included in the system setting information. ).

  Next, in step S <b> 12, the display state acquisition unit 22 waits until the communication unit 17 of the information bulletin board 2 receives the system setting information and receives a reception signal transmitted from the communication unit 17 and notifying that it has been received. When receiving the reception signal, the display state acquisition unit 22 proceeds to step S14. In the information bulletin board 2, after the communication unit 17 receives the system setting information, the display control unit 18 causes the display unit 50 to display characters and the like based on the system setting information. The information bulletin board 2 displays the character string specified by the control character string in the color specified by the RGB value of the control character color in the display area specified by the block number included in the system setting information. Thereby, for example, information as shown in FIG. 3 is displayed on the information bulletin board 2.

  In step S <b> 14, the display state acquisition unit 22 transmits an image acquisition command to the imaging device 3. In this case, when receiving the acquisition command, the imaging unit 20 of the imaging device 3 acquires an image (see FIG. 3) of the display unit 50 of the information bulletin board 2 based on the acquisition command, and controls this image from the communication unit 17. It outputs to the apparatus 4 (display state acquisition part 22).

  Next, in step S <b> 16, the display state acquisition unit 22 acquires the image output from the imaging device 3. In the following, the image acquired by the display state acquisition unit 22 in step S16 is also referred to as a “pre-control image”. The display state acquisition unit 22 delivers the acquired pre-control image to the character color correction unit 23.

  Next, in step S <b> 18, the character color correction unit 23 extracts one representative point of the pixel of the character of each block 51 to 54 included in the system setting information output from the display control unit 21 to the information bulletin board 2. Then, the character color correction unit 23 acquires the first RGB value of the extracted pixel and converts it into a YCrCb value. The CrCb value obtained here is referred to as a first Cr value and a first Cb value.

Here, the Y value indicating brightness, the Cr value indicating color difference, and the Cb value can be calculated by the following equations (1) to (3) using RGB values.
Y = 0.299 × R + 0.58 × G + 0.114 × B (1)
Cr = 0.500 × R−0.419 × G−0.081 × B (2)
Cb = −0.169 × R−0.332 × G + 0.500 × B (3)

  For example, an example of a calculation result (YCrCb value obtained by converting RGB values) of the character color of the second block 52 output as the system setting information is shown in the first line of FIG. As shown in the first line of FIG. 6, the Y value of the character color of the second block 52 of the system setting information is 188.60, the Cr value (first Cr value) is 8.10, The Cb value (first Cb value) is assumed to be −50.20.

  Next, in step S <b> 20, the character color correction unit 23 extracts one representative point of character pixels in the image (pre-control image) acquired from the imaging device 3 from each of the blocks 51 to 54. Then, the character color correction unit 23 acquires the RGB value of the extracted pixel as the second RGB value, and converts it into a YCrCb value using the above equations (1) to (3). Note that the Y value obtained in step S20 is hereinafter also referred to as a “first Y value”.

  Here, an example of the YCrCb value for the character color of the second block 52 in the pre-control image when the character is output based on the system setting information is shown in the second line of FIG. For example, it is assumed that the second RGB values of the characters of the second block 52 extracted from the pre-control image are R: 230, G: 200, and B: 100. In this case, as a result of converting the second RGB value to the YCrCb value using the above formulas (1) to (3), the Y value (first Y value) is 197.57, and the Cr value is It is assumed that the Cb value was −55.27.

  When comparing the first line and the second line in FIG. 6, the character color (first RGB) displayed on the information bulletin board 2 on the first line and the character color (second RGB) of the pre-control image on the second line, That is, the character color visually recognized by the driver should match. However, in FIG. 6, they do not match. This is because the character color of the information bulletin board 2 is captured as a color different from the original color due to external factors such as sunlight. This suggests that a driver traveling on a highway is recognized as a color different from the original character color.

Therefore, in the next step S22, the brightness Y (first Y value) obtained by converting the second RGB value of the pre-control image and the first RGB value of the system setting information are obtained. Correction data (third RGB value) such as characters is created using the Cr value and Cb value (first Cr value, Cb value). Here, since R, G, and B can be calculated based on the following equations (4) to (6), the first Y value, the first Cr value, and the first Cb value are expressed by the following equations ( By substituting in 4) to (6), the third RGB value is obtained.
R = Y + 1.402 × Cr (4)
G = Y−0.714 × Cr−0.344 × Cb (5)
B = Y + 1.772 × Cb (6)

  For example, in the example of FIG. 6, as shown in the third row, equations (4) to (6) are calculated using Y: 197.57, Cr: 8.10, and Cb: -50.20. As a result, R: 209, G: 209, and B: 109 are obtained as correction data (third RGB values). The first RGB values (system setting information) of the characters in the initial second block 52 were R: 200, G: 200, and B: 100, but the correction obtained by the process of step S22. The data (third RGB value) is R: 209, G: 209, and B: 109.

  The background color of the display unit 50 of the information bulletin board 2 is normally black. However, in the processing of steps S18 to S22, the RGB value of the background color of the display unit 50 of the information bulletin board 2 is set for each of the blocks 51 to 54. The background color may be corrected in addition to the character color. In this case, the RGB value (first RGB value) of the background color of the system setting information is acquired in step S18, and converted to a CrCb value (first Cr value and first Cb value). Further, the RGB value (second RGB value) of the background color of the second block 52 is acquired from the pre-control image, and converted into a YCrCb value. Then, the RGB value (third RGB value) of the background color using the Y value (first Y value) of the pre-control image and the Cr value and Cb value (first Cr, Cb value) of the original character color ) To obtain correction data.

  Next, in step S24, the display control unit 21 transmits the correction data obtained in step S22 toward the communication unit 17 of the information bulletin board 2. In this case, the display control unit 18 of the information bulletin board 2 displays characters and the like on the display unit 50 based on the correction data. Thus, if the display unit 50 is normal (no dirt or deterioration), it is considered that display according to the system setting information can be performed. When receiving the correction data, the communication unit 17 transmits a reception signal notifying that the correction data has been received to the display state acquisition unit 22 of the control device 4.

  Next, in step S26, the display state acquisition unit 22 waits until it receives a reception signal from the communication unit 17 of the information bulletin board 2, and when it is received, the process proceeds to step S30 in FIG.

  When the process proceeds to step S <b> 30, the display state acquisition unit 22 transmits an image acquisition command to the imaging device 3 as in step S <b> 14. In this case, when receiving the acquisition command, the imaging unit 20 of the imaging device 3 acquires an image (see FIG. 3) of the display unit 50 of the information bulletin board 2 based on the acquisition command, and controls this image from the communication unit 17. It outputs to the apparatus 4 (display state acquisition part 22).

  Next, in step S32, as in step S16, the display state acquisition unit 22 acquires an image output from the imaging device 3. In the following, the image acquired by the display state acquisition unit 22 in step S16 is also referred to as a “post-control image”. The display state acquisition unit 22 passes the acquired image to the correction value determination unit 24.

  Next, in step S34, the correction value determination unit 24 extracts one representative point of the character pixel from each of the blocks 51 to 54 of the post-control image, and uses the RGB value of the pixel as the fourth RGB value. get.

  Next, in step S36, the fourth RGB value is compared with one representative third RGB value of the same block to determine whether or not the fourth RGB value is abnormal. In this case, for example, in the fourth RGB value and the third RGB value, the absolute value of the difference between the R values, the absolute value of the difference between the G values, and the absolute value of the difference between the B values are calculated. It is determined whether or not the fourth RGB value is abnormal depending on whether or not the predetermined threshold value m is exceeded. The threshold value m can be set to 5, for example. In addition, it can be said that this step is a process for determining whether the display unit 50 is normal or abnormal (dirt or LED deterioration occurs).

  If the determination in step S36 is negative, that is, if the fourth RGB value is normal, the process proceeds to step S46, and the correction value determination unit 24 indicates that the display unit 50 is normal. 15 for output (display, etc.).

  On the other hand, if the determination in step S36 is affirmative, that is, if the fourth RGB value is abnormal, the process proceeds to step S38. In step S38, the correction value determination unit 24 converts the representative fourth RGB value of each point of each block into a YCrCb value using the above equations (1) to (3). The Cr value and the Cb value obtained in step S38 are referred to as “second Cr value” and “second Cb value”.

  Next, in step S40, a CrCb value (second Cr value, Cb value) based on the fourth RGB value of one representative point of each block and a CrCb value (first value) based on the first RGB value of the same point. It is determined whether the absolute value of the difference between the Cr value and the Cb value of 1 is greater than the threshold value n. As the threshold value n, for example, n = 5 can be adopted as a condition for classification into similar colors. Here, it is assumed that the RGB value of the fourth row in FIG. 6 is obtained as the fourth RGB value, and 35.91 and −46.82 are obtained as the second Cr value and Cb value.

in this case,
| First Cr Value−Second Cr Value | = | 8.10−35.91 |
= 27.81 (7)
| First Cb value−Second Cb value | = | −50.20 − (− 46.82) |
= 3.38 (8)
It becomes. Accordingly, as a result of the above equation (7), since the absolute value of the difference in Cr value exceeds the threshold value n = 5, the determination in step S40 is affirmed. When the determination in step S40 is affirmed, the process proceeds to step S42, and the correction value determination unit 24 determines that the display unit 50 is dirty. In the next step S46, the correction value determination unit 24 outputs (displays, etc.) the determination result (dirt of the display unit 50) via the output device 15.

  On the other hand, if the determination in step S40 is negative, the process proceeds to step S44, and the correction value determination unit 24 determines that the LED included in the display unit 50 has deteriorated (failed) because the display unit 50 is not dirty. To do. In the next step S46, the correction value determination unit 24 outputs (displays, etc.) the determination result (deterioration of the display unit 50) via the output device 15. In addition, after the process of step S46 is performed, the whole process of FIG. 4, FIG. 5 is complete | finished.

  Here, FIG. 7 shows a table regarding RGB values and YCrCb values when the LED deteriorates (a table corresponding to FIG. 6). As shown in FIG. 7, when the LED is deteriorated, the fourth RGB value is abnormal compared to the third RGB value (threshold value m = 5 is exceeded) (step S36: affirmative) The absolute value of the difference between the second Cr value and Cb value and the first Cr value and Cb value is smaller than the threshold value n (No at Step S40). Therefore, in the case of FIG. 7, it is determined in step S44 that the LED is deteriorated.

  In the present embodiment, since representative pixels are extracted and processed for each of the blocks 51 to 54, whether each block 51 to 54 is normal, dirty, or the LED is deteriorated. Can be determined.

  4 and 5 are executed each time new system setting information is input to the information management apparatus 5 from an external apparatus. However, with respect to the information bulletin board 2 that is easily affected by sunlight, even if new system setting information is not input, the processes of FIGS. 4 and 5 are executed at predetermined time intervals (for example, every few tens of minutes). Also good.

  As can be seen from the above description, the character color correction unit 23 of the present embodiment is an example of a first calculation unit, a second calculation unit, and a third calculation unit. The correction value determination unit 24 is an example of a fourth calculation unit, a first determination unit, a detection unit, and a second determination unit.

  As described above in detail, according to the present embodiment, the character color correction unit 23 determines the RGB value (first RGB value) indicating the color of the character or graphic displayed on the display unit 50 of the information bulletin board 2 as follows. It converts into the Cr value and Cb value (1st Cr value, Cb value) of the color of a character or a figure (S18), a character or a figure is displayed on the display part 50 based on a 1st RGB value (S10), A second RGB value, which is an RGB value indicating the color of a character or a figure in an image (pre-control image) obtained by imaging the display unit 50 with the imaging device 3, is converted into a Y value (first Y value) (S20). ), A third RGB value (correction data), which is an RGB value indicating the color of the character or figure, is created from the first Y value, the first Cr value, and the Cb value (S22). Then, the correction value determination unit 24 displays characters or figures on the display unit 50 based on the third RGB values (S24), and changes the color of the characters or figures in the image obtained by imaging the display unit 50 with the imaging device 3. The indicated RGB value (fourth RGB value) is converted into the Cr value and Cb value (second Cr value, Cb value) of the character or figure in the image (S38), and the second Cr value, Cb value and Based on the comparison result with the first Cr value and the Cb value, it is determined whether or not the display unit 50 is dirty (S40). As described above, in the present embodiment, the second Cr value and the Cb value after the display unit 50 is controlled so that characters and figures are displayed with the first RGB value on the display unit 50 are used as the first RGB value. Since the display unit 50 is compared with the first Cr and Cb values obtained by converting the values to determine whether or not the display unit 50 is dirty, the display unit 50 is also affected by sunlight or lighting. The cause of the deterioration in the visibility of the display unit 50 can be correctly specified. Even when the display unit 50 is normal, the display color is adjusted according to the brightness of the environment around the display unit 50, so that the color originally intended or a color close to the intended color is used. Thus, it becomes possible to make the driver recognize characters and figures. As a result, the importance of information can be reliably transmitted to the driver.

  In the present embodiment, the correction value determination unit 24 executes a process (S36) of detecting an abnormality of the display unit 50 based on the comparison result between the third RGB value and the fourth RGB value. When it is determined that the display unit 50 is abnormal and the display unit 50 is not dirty, it is determined that the LED of the display unit 50 has deteriorated. Thereby, even in a situation where the display unit 50 is affected by sunlight or illumination, it can be accurately determined whether or not the LED of the display unit 50 has deteriorated. Thus, by using the display system of the present embodiment, an administrator who manages the expressway can clean the information bulletin board 2 and perform maintenance at an appropriate timing based on the determination result. Become. Further, the visibility of the information bulletin board 2 by the driver can be improved by cleaning and maintenance of the information bulletin board 2.

  In the above embodiment, the process of step S36 may be performed after step S40 is denied. In this case, when the determination in step S36 is affirmed, the process proceeds to step S44, and when the determination is negative, the process proceeds to step S46.

  In the above-described embodiment, the case where the display unit 50 of the information bulletin board 2 corrects the character color for each of the blocks 51 to 54 and determines whether or not the display unit 50 is dirty has been described. However, the present invention is not limited to this. Absent. For example, it is good also as correcting the character color for every pixel and determining whether the display part 50 is dirty.

  Note that the control target of the display system 1 of the above embodiment is not limited to the information bulletin board 2 installed on the expressway. For example, it may be an information bulletin board on a general road, or other information bulletin board installed outdoors.

  The above processing functions can be realized by a computer. In that case, a program describing the processing contents of the functions that the processing apparatus should have is provided. By executing the program on a computer, the above processing functions are realized on the computer. The program describing the processing contents can be recorded on a computer-readable recording medium (except for a carrier wave).

  When the program is distributed, for example, it is sold in the form of a portable recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory) on which the program is recorded. It is also possible to store the program in a storage device of a server computer and transfer the program from the server computer to another computer via a network.

  The computer that executes the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its own storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. Further, each time the program is transferred from the server computer, the computer can sequentially execute processing according to the received program.

  The above-described embodiment is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

In addition, the following additional remarks are disclosed regarding description of the above embodiment.
(Supplementary Note 1) From the first RGB value, which is the RGB value indicating the color of the character or graphic displayed on the display section of the information bulletin board, the first Cr value, which is the Cr value and Cb value of the character or graphic color, and the first 1 Cb value is calculated,
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device To calculate a first Y value that is a Y value of the character or graphic in the image,
From the first Y value, the first Cr value, and the first Cb value, a third RGB value that is an RGB value indicating the color of the character or figure is calculated.
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device From the value, a second Cr value and a second Cb value, which are the Cr value and Cb value of the character or graphic in the image, are calculated,
Determining whether the display section is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value;
A display unit state determination method, wherein a computer executes a process.
(Additional remark 2) The process which detects abnormality of the said display part based on the comparison result of the said 3rd RGB value and the said 4th RGB value,
The computer executes a process of determining that the display unit is faulty when an abnormality of the display unit is detected and the determination unit determines that the display unit is not dirty. The display unit state determination method according to claim 1.
(Supplementary Note 3) From the first RGB value that is the RGB value indicating the color of the character or graphic displayed on the display unit of the information bulletin board, the first Cr value and the first Cr value that are the Cr value and Cb value of the character or graphic color 1 Cb value is calculated,
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device To calculate a first Y value that is a Y value of the character or graphic in the image,
From the first Y value, the first Cr value, and the first Cb value, a third RGB value that is an RGB value indicating the color of the character or figure is calculated.
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device From the value, a second Cr value and a second Cb value, which are the Cr value and Cb value of the character or graphic in the image, are calculated,
Determining whether the display section is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value;
A display unit state determination program which causes a computer to execute processing.
(Additional remark 4) The process which detects abnormality of the said display part based on the comparison result of the said 3rd RGB value and the said 4th RGB value,
An additional note that causes the computer to execute a process of determining that the display unit is faulty when an abnormality of the display unit is detected and the determination unit determines that the display unit is not dirty. The display unit state determination program according to 3.
(Additional remark 5) From the 1st RGB value which is the RGB value which shows the color of the character or the figure which is displayed on the display section of the information bulletin board, the 1st Cr value which is the Cr value and the Cb value of the color of the character or the figure A first calculation unit for calculating a Cb value of 1;
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device A second calculation unit that calculates a first Y value that is a Y value of the character or graphic in the image;
A third calculator that calculates a third RGB value, which is an RGB value indicating the color of the character or graphic, from the first Y value, the first Cr value, and the first Cb value; ,
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device A fourth calculation unit for calculating a second Cr value and a second Cb value, which are the Cr value and Cb value of the character or graphic in the image, from the value;
A first determination for determining whether or not the display unit is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value. And
A display unit state determination device.
(Supplementary Note 6) Based on a comparison result between the third RGB value and the fourth RGB value, a detection unit that detects an abnormality in the display unit;
A second determination unit that determines that the display unit is defective when the detection unit detects an abnormality of the display unit and the first determination unit determines that the display unit is not soiled;
The display part state determination apparatus of Additional remark 5 provided with these.
(Appendix 7) An information bulletin board having a display unit;
An imaging device for imaging the display unit;
A display system comprising the display unit state determination device according to appendix 5 or 6.

DESCRIPTION OF SYMBOLS 1 Display system 2 Information bulletin board 3 Imaging device 4 Control apparatus (display part state determination apparatus)
23 character color correction unit (first calculation unit, second calculation unit, third calculation unit)
24 correction value determination unit (fourth calculation unit, first determination unit, detection unit, second determination unit)
50 display section

Claims (5)

From the first RGB value that is the RGB value indicating the color of the character or graphic displayed on the display unit of the information bulletin board, the first Cr value and the first Cb value that are the Cr value and Cb value of the character or graphic color To calculate
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device To calculate a first Y value that is a Y value of the character or graphic in the image,
From the first Y value, the first Cr value, and the first Cb value, a third RGB value that is an RGB value indicating the color of the character or figure is calculated.
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device From the value, a second Cr value and a second Cb value, which are the Cr value and Cb value of the character or graphic in the image, are calculated,
Determining whether the display section is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value;
A display unit state determination method, wherein a computer executes a process. A process of detecting an abnormality in the display unit based on a comparison result between the third RGB value and the fourth RGB value;
The computer executes a process of determining that the display unit is faulty when an abnormality of the display unit is detected and the determination unit determines that the display unit is not dirty. Item 4. The display unit state determination method according to Item 1. From the first RGB value that is the RGB value indicating the color of the character or graphic displayed on the display unit of the information bulletin board, the first Cr value and the first Cb value that are the Cr value and Cb value of the character or graphic color To calculate
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device To calculate a first Y value that is a Y value of the character or graphic in the image,
From the first Y value, the first Cr value, and the first Cb value, a third RGB value that is an RGB value indicating the color of the character or figure is calculated.
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device From the value, a second Cr value and a second Cb value, which are the Cr value and Cb value of the character or graphic in the image, are calculated,
Determining whether the display section is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value;
A display unit state determination program which causes a computer to execute processing. From the first RGB value that is the RGB value indicating the color of the character or graphic displayed on the display unit of the information bulletin board, the first Cr value and the first Cb value that are the Cr value and Cb value of the character or graphic color A first calculation unit for calculating
A second RGB value that is an RGB value indicating the color of the character or figure in an image obtained by displaying the character or figure on the display unit based on the first RGB value and picking up the display unit with an imaging device A second calculation unit that calculates a first Y value that is a Y value of the character or graphic in the image;
A third calculator that calculates a third RGB value, which is an RGB value indicating the color of the character or graphic, from the first Y value, the first Cr value, and the first Cb value; ,
The fourth RGB which is an RGB value indicating the color of the character or figure in the image obtained by displaying the character or figure on the display unit based on the third RGB value and imaging the display unit by the imaging device A fourth calculation unit that calculates a second Cr value and a second Cb value that are the Cr value and the Cb value of the character or graphic in the image from the value;
A first determination for determining whether or not the display unit is dirty based on a comparison result between the second Cr value and the second Cb value and the first Cr value and the first Cb value. And
A display unit state determination device. An information bulletin board having a display unit;
An imaging device for imaging the display unit;
A display system comprising: the display unit state determination device according to claim 4.

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