JP2012175183A - Display state evaluation system for display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaluation system of the display state of a display device, which determines various abnormal display states on which a viewer feels discomfort.SOLUTION: An image taken by a camera 10 is acquired (S41), the acquired image is divided into plural regions (S42), and a luminance value of each region is calculated (S43). On the basis of the luminance value, a luminance difference is calculated (S44), and the variation pattern of the luminance difference is determined (S45). Moreover, a false signal is acquired and the variation pattern of the difference of the false signal is determined (S46). Then, the degree of correlation between both variation patterns is calculated (S47) and it is determined from the degree of the correlation whether the display state is abnormal (S48).

Description

  The present invention relates to a display state evaluation system for a display, and more particularly to a system for automatically determining an abnormality in a display state.

  As a device for automatically determining a display abnormality of a display device, a device of Patent Document 1 has been conventionally known. The device of Patent Literature 1 includes a camera that captures a display device and a personal computer that analyzes an image captured by the camera. The personal computer is provided with a memory, and the luminance for each picture element of the video imaged by the camera is stored in this memory. Then, the flicker of display on the display device is determined from the standard deviation of the luminance for each picture element.

Japanese Patent Laid-Open No. 2005-10642

  When the flicker is determined based on the standard deviation as in Patent Document 1, it is not possible to determine that there is flicker unless the luminance change appears as a significant difference in the standard deviation. That is, unless the luminance change is flickering that is repeated a certain number of times (periodic flickering), it cannot be determined that there is flickering.

  On the other hand, display abnormalities that people feel uncomfortable include those other than periodic flickering. For example, when considering an on-vehicle display that displays a change in luminance such as momentary lighting and extinction, and a meter needle as a display, a sense of incongruity is felt even when the meter needle does not operate smoothly. However, the apparatus of Patent Document 1 can only determine flicker that indicates a periodic luminance change, and cannot determine various other display abnormalities.

  The present invention has been made based on this circumstance, and the object thereof is to determine various display state abnormalities that people feel uncomfortable in the evaluation system for the display state of the display. .

  In order to achieve the object, the camera captures the display device over time, and the information processing apparatus acquires the image captured by the camera and changes the brightness of the image over time. Further, a change pattern of the luminance difference is determined based on the luminance calculated over time. Then, the display abnormality determination means determines whether there is an abnormality in the display state of the display, based on the comparison between the luminance difference change pattern and a predetermined reference pattern.

  When momentary lighting / extinguishing occurs, the luminance changes. In addition, a change in luminance also occurs when the operation of the graphic displayed on the display is an abnormal operation. Since the change in luminance can be determined from the luminance difference, the luminance difference change pattern is used as in the present invention, and whether the display state of the display device is abnormal by comparing the luminance difference change pattern with the reference pattern. If determined, it is possible to determine abnormalities in various display states in which a person feels uncomfortable.

  In the invention described in claim 2, the display abnormality determination means uses a preset abnormality change pattern as the reference pattern. In this way, if a preset abnormal change pattern is used, it can be determined that the luminance difference change pattern is abnormal when the brightness difference change pattern is similar to the preset abnormal change pattern.

  Furthermore, as in the invention described in claim 3, a plurality of types of abnormality change patterns respectively corresponding to a plurality of types of abnormality in the display state can be used as the abnormality change pattern.

  According to a fourth aspect of the present invention, the apparatus further includes a pseudo signal generating device that generates a pseudo display change signal, which is a signal for changing the display state of the display, and outputs the display change signal to the display. Then, the display abnormality determination unit uses a pseudo change pattern of the display change signal generated as the reference pattern. In this way, it is possible to determine the presence or absence of display abnormality of the display by setting the same conditions as when the display is mounted on the vehicle.

  Specifically, the determination by the display abnormality determination means may be performed based on a comparison between the occurrence time of the feature point in the luminance difference change pattern and the occurrence time of the feature point in the reference pattern, as in claim 5. it can. This characteristic point is, for example, at least one of a rising point and a falling point of a signal in the change pattern.

  In addition, the determination in the display abnormality determination unit is performed based on a comparison between a change in luminance difference at a predetermined time of the abnormal change pattern and a change in luminance difference at a predetermined time in the change pattern of the luminance difference, as in claim 7. May be.

  According to the eighth aspect of the present invention, the image is divided into a plurality of areas, and the luminance is calculated over time for each area for a part or all of the areas. The change pattern of the luminance difference is determined for one or a plurality of preset areas. In this way, since the change pattern of the brightness difference is determined for a part of the image, a detailed change pattern of the brightness difference limited to a part of the image can be determined.

  According to the ninth aspect of the present invention, the change pattern of the luminance difference is determined for each of the plurality of regions. The reference patterns to be compared with the plurality of luminance difference change patterns are also different reference patterns for each luminance difference change pattern. In this way, it is possible to determine abnormalities in different display states for a plurality of areas.

  In the tenth aspect of the present invention, determination is performed by comparing one luminance difference change pattern with a plurality of different reference patterns. In this way, a plurality of types of display state abnormalities can be determined for one region.

It is a figure which shows the whole structure of the display state evaluation system to which this invention was applied. It is a flowchart which shows the procedure of the display state test of the indicator D performed using the display state evaluation system 1 of FIG. It is a figure which shows the example of abnormality of the display state of the indicator. It is a flowchart which shows in detail the display abnormality determination process which operation PC40 performs. It is a figure explaining the specific example of the display abnormality determination process of FIG. It is a figure explaining the correlation calculated by step S47 of FIG. It is a specific example of the abnormality determination in 1st Embodiment, Comprising: It is a figure explaining the example different from FIG. It is a flowchart which shows in detail the display abnormality determination process which operation PC40 performs in 2nd Embodiment. It is a figure explaining the specific example of the display abnormality determination process in 2nd Embodiment. It is a figure explaining the calculation method of a coincidence degree. It is a specific example of the abnormality determination in 2nd Embodiment, Comprising: It is a figure explaining the example different from FIG. It is a figure explaining the other specific example 1. FIG. It is a figure explaining the other specific example 2. FIG. It is a figure explaining the other specific example 3. FIG. It is a figure explaining the other specific example 4. FIG. It is a figure explaining the other specific example 5. FIG. It is a figure explaining the other specific example 6. FIG. It is a figure explaining the other specific example 7. FIG.

(First embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of a display state evaluation system 1 to which the present invention is applied. As shown in FIG. 1, the display state evaluation system 1 of this embodiment includes a camera 10, a simulator 20, and an operation PC 40.

  The camera 10 continuously captures the screen of the evaluation target display D, and outputs the captured image to the operation PC 40. Although the number of cameras 10 is two in FIG. 1, the number of cameras 10 is not particularly limited, and may be one or three or more. In this embodiment, the display device D captured by the camera 10 is a display device (vehicle-mounted display device) mounted on a vehicle, and displays a speed meter, a tachometer, and the like.

  The simulator 20 is a device that generates a simulated environment for the display D when the display D is mounted on a vehicle, and includes, for example, a simulated power supply and a communication line. The simulator 20 also has a function as a pseudo signal generation device in the scope of the claims, and is a signal input to the display D when the display D is mounted on a vehicle. A display change signal that is a signal for instructing a change in display state is generated in a pseudo manner and is output to the display device D (hereinafter, the pseudo display change signal is referred to as a pseudo signal).

  The simulator 20 generates various test conditions (power supply conditions, communication conditions, etc.) and various pseudo signals based on an automatic operation by the display state test program or an operator's direct input operation. As the pseudo signal, for example, a pseudo signal corresponding to a signal for turning on / off the direction indicating indicator lamp (indicating that the direction indicator lamp is lit) of the display unit D, and on / off of an AFS (Adaptive Front-Lighting System) There is a pseudo signal or the like corresponding to the signal indicating.

  The operation PC 40 includes a display state test program 41, a camera operation unit 42, a simulator operation unit 43, an image processing unit 44, an image analysis unit 45, an image determination unit 46, an image determination result output unit 47, a pseudo signal processing unit 48, and a storage unit. 49.

  When the display state test program 41 is executed, the units 42 to 49 of the operation PC 40 are operated according to the program to determine whether the display state of the display D is abnormal.

The camera operation unit 42 performs operations of the camera 10 such as recording start and end of the screen of the display D by the camera 10 according to the display state test program 41. The simulator operation unit 43 performs an operation on the simulator 20 and measures a signal output from the simulator 20 to the display unit D. The image processing unit 44 acquires an image captured by the camera 10, and performs preprocessing for image analysis in the image analysis unit 45 on the acquired image. The image analysis unit 45 analyzes the image processed by the image processing unit 44 and determines the luminance of a predetermined portion of the image.
The image determination unit 46 determines a change pattern of the luminance difference based on the luminance analyzed by the image analysis unit 45, and further compares the change pattern of the luminance difference with a predetermined reference pattern, so that the display D Determine if the display status is abnormal. The image determination result output unit 47 is a monitor, for example, and outputs the determination result of the image determination unit 46. The pseudo signal processing unit 48 acquires a pseudo signal from the simulator operation unit 43 and creates a change pattern of the pseudo signal difference. The storage unit 49 is a writable storage unit and stores the processing results of the units 42 to 48 of the operation PC 40. The storage unit 49 also stores a signal indicating an image captured by the camera 10 (hereinafter referred to as a captured image signal) and a luminance difference change pattern described later. The operation PC 40 corresponds to the information processing device in the claims.

  FIG. 2 is a flowchart showing the procedure of the display state test of the display D performed using the display state evaluation system 1 of FIG. In the display state test, first, as shown in step S1, recording of the display D by the camera 10 is started. This start may be started by an operator's switch operation, or the operation PC 40 may control the camera 10 to automatically start recording. After step S1, captured image signals are sequentially input from the camera 10 to the operation PC 40, and the operation PC 40 stores the input captured image signals in the storage unit 49.

  In subsequent step S2, test conditions are generated. This test condition is, for example, disconnection or short circuit. It also generates pseudo signals for various sensor signals. This step S2 is performed when the operator operates the simulator 20. The pseudo signal generated by the simulator 20 is input to the display D. Further, the operation PC 40 measures a pseudo signal input from the simulator 20 to the display device D and stores it in the storage unit 49.

  In subsequent step S3, the recording of the display D by the camera 10 is terminated. This step S may be performed by the operator, or the operation PC 40 may determine that a predetermined time has elapsed, and the operation PC 40 may control the camera 10 to end the recording.

  The subsequent step S4 is a process performed by the operation PC 40, and an abnormality in the display state of the display D is determined based on the captured image signal and the pseudo signal acquired after step S1 and before executing step S3. . The process of step S4 will be described later with reference to FIG.

  The subsequent step S5 is also a process of the operation PC 40, and the determination result determined in step S4 is output from the image determination result output unit 47. This completes the series of procedures for the display state test.

  Before explaining the display abnormality determination process in step S4 described above, an example of the display state abnormality determined in step S4 will be described. FIG. 3 is an example of an abnormality in the display state of the display D. FIG. 3A shows that a lamp indicating the state of a certain device is lit for a moment at time t2. FIG. 3B shows that a letter indicating brake abnormality is lit for a moment at time t2.

  The operation PC 40 determines the display abnormality illustrated in FIG. 3 and other various display abnormalities by executing a display abnormality determination process. FIG. 4 is a flowchart showing in detail the display abnormality determination process executed by the operation PC 40. First, in step S41, the captured image signal recorded during steps S1 to S3 in FIG.

  In subsequent step S42, screen division is performed. In this screen division, a captured image obtained by imaging the display D is divided into a plurality of regions, and how the screen is divided is set in advance. FIG. 5 is a diagram for explaining a specific example of a series of processes of the display abnormality determination process of FIG. 4 such as the screen division process of step S42. An example of screen division in step S42 is shown in FIG. 5A. In this example, division lines are set at equal intervals in the vertical and horizontal directions, and a rectangular range surrounded by the division lines is divided into each division. It is an area.

The subsequent step S43 is processing equivalent to the luminance calculation means in the claims, and the luminance value of the divided area is set at predetermined time intervals (50 ms in FIG. 5) over the entire period from the start to the end of recording. Every). The divided areas for calculating the luminance value are all the divided areas divided in step S42. Here, in order to simplify the description, the luminance value of the region R shown in FIG.
FIG. 5 (B) shows the change over time of the brightness value calculated in step S43. In the example of FIG. 5 (B), the brightness value (= 70) indicating lighting is turned off every 50 ms. And a luminance value (= 0) indicating the above are repeated.

  In the subsequent step S44, the luminance difference is calculated by subtracting the luminance at the previous luminance calculation time from the luminance at each luminance calculation time, using the luminance value calculated at a predetermined time interval in step S43. By calculating the luminance difference, the display abnormality can be determined under the same conditions when the absolute value of the luminance changes from 0 → 100 → 0 and when the absolute value of the luminance changes from 150 → 250 → 150. Compared with it, versatility is enhanced. FIG. 5C shows an example of the luminance difference calculated in step S44.

  The subsequent step S45 corresponds to a change pattern determining means in the claims, and determines a change pattern of the luminance difference indicating the temporal change of the luminance difference calculated in step S44. In step S46, the pseudo signal change pattern is acquired and the pseudo signal difference change pattern is determined.

  FIGS. 5D and 5E respectively show the time change of the switch signal as a pseudo signal and the difference between the switch signals. It should be noted that the time interval for calculating the difference between the switch signals is equal to or shorter than the time interval for calculating the luminance difference. Here, since the time interval is sufficiently shorter than the above time interval, as shown in FIG. 5E, the difference between the switch signals is a value even at a time different from the luminance difference calculation cycle (every 50 ms). Has changed.

  In the subsequent step S47, the degree of correlation between the luminance difference change pattern determined in step S45 and the pseudo signal difference change pattern determined in step S46 is calculated. In calculating the degree of correlation, the feature of the luminance difference change pattern is extracted, and the feature corresponding to the luminance difference change pattern is also extracted from the pseudo signal difference change pattern. Then, the degree of correlation is calculated from the extracted features. The extracted features include, for example, a luminance difference presenting a positive value, a luminance difference presenting a negative value, a luminance difference local maximum, a local minimum, and the like. Is set.

  FIG. 6 is a diagram for explaining the degree of correlation calculated in step S47. In this embodiment, the time difference between the present time of the positive value and the current time difference of the negative value is calculated. The degree of correlation is calculated using these two time differences. Here, the following will be described using the average value of two time differences as the degree of correlation. The correlation degree calculated in this way means that the smaller the value is, the more the brightness difference and the pseudo signal difference are correlated.

  In subsequent step S48, an abnormality in the display state of the display D is determined based on the correlation degree calculated in step S47. For example, if the degree of correlation is smaller than a preset threshold value, that is, if the correlation between the luminance difference and the pseudo signal difference is high, it is considered that the display state of the display D has changed according to the pseudo signal. The display state of the display device D is determined to be normal. Conversely, if the degree of correlation is greater than or equal to a preset threshold value, it is considered that the display state of the display D has shown a change that does not correspond to the pseudo signal, and therefore the display state of the display D is determined to be abnormal. . Steps S46 to S48 are processing corresponding to display abnormality determination means in the claims.

If this step S48 is performed, the process shown in FIG. 4 will be complete | finished. Thereafter, the determination result is output from the display screen of the operation PC 40 in step S5 of FIG.
(Specific example 2 of the first embodiment)
Next, a specific example of abnormality determination in the first embodiment, which is an example different from FIG. 5, will be described with reference to FIG. In FIG. 7, (A) is a picked-up image picked up by the camera 10, and in this specific case, picked up at a cycle of 40 ms. (B) is the luminance corresponding to each captured image. In this example, the image is divided into small squares, and the average luminance for each divided region is determined. (C) is a luminance difference, and FIG. 7 shows the luminance difference in the lower right region of the divided regions shown in the figure. As can be seen from FIGS. 7A to 7C, this case is a case where the “AFS OFF” lamp is extinguished for a short time (for example, 100 ms or less). The last (D) shows the difference between the switch (SW) signal, which is a pseudo signal, and the SW signal. This SW signal is a signal for instructing lighting of “AFS OFF” in the captured image. The SW signal remains in the ON state during the period shown in FIG. 7, so that the difference between the SW signals remains at a constant value of zero.

  The luminance difference in FIG. 7C changes in value between 120 ms and 200 ms, while the SW signal difference does not change. That is, there is no correlation between the two. Therefore, it can be determined that the display state of the display D is abnormal.

  As described above, according to the first embodiment described above, the change pattern of the brightness difference (that is, the change over time in the brightness difference of the display D) is determined from the image of the display D captured by the camera 10. The change pattern of the luminance difference is compared with the change pattern of the difference of the pseudo signal. Therefore, it can be determined whether the luminance change of the display device D is a normal change corresponding to the signal input to the display device D. In addition, since a change in luminance occurs even when the indicator D is turned on / off instantaneously, the fact that the instantaneous turn-on / off occurs is reflected in the change pattern of the luminance difference. Therefore, as in this embodiment, by comparing the change pattern of the luminance difference with the change pattern of the difference of the pseudo signal, it is automatically determined whether or not the instantaneous lighting / turning off has occurred due to the abnormality of the display D. can do.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The system configuration of the second embodiment has the configuration shown in FIG. 1 as in the first embodiment, and the test procedure is the procedure shown in FIG. 2 as in the first embodiment. However, the contents of the display abnormality determination process executed in step S4 in FIG. 2 are different from those in the first embodiment. In the first embodiment, the change pattern of the brightness difference is compared with the change pattern of the difference of the pseudo signal. In the second embodiment, the change pattern of the brightness difference is compared with the abnormal change pattern. This abnormal change pattern is a change pattern of a luminance difference when the display device D is in an abnormal state. In the second embodiment, one or more types of abnormal change patterns are stored in the storage unit 49. ing. This abnormal change pattern may be an actual luminance difference change pattern when the display D is abnormal, or may be a pattern set arbitrarily.

  FIG. 8 is a flowchart showing in detail the display abnormality determination process executed by the operation PC 40 in the second embodiment. In FIG. 8, in the step given the same step number as FIG. 4, the same processing as in FIG. 4 is executed. That is, also in FIG. 8, an image is acquired from the camera 10 (step S41), the captured image is divided (step S42), the luminance of the divided area is calculated (step S43), and the luminance difference is calculated (step S42). S44), a change pattern of the luminance difference is determined (step S45).

  After step S45 is executed, the degree of coincidence between the luminance difference change pattern determined in step S45 and the abnormal change pattern stored in the storage unit 49 is calculated in step S47-1.

  FIG. 9 is a diagram for explaining a specific example of display abnormality determination processing in the second embodiment, and FIGS. 9A to 9C are the same as FIGS. 5A to 5C, respectively. FIG. 9D is an example of the abnormal change pattern used in step S47-1 in FIG. The abnormal change pattern shown in FIG. 9D is a past actual abnormal case (with flickering, and the luminance difference is a large positive value (+70) → 0 → a negative value having a large absolute value (−70). It repeats with a short cycle.

  Here, the degree of match will be specifically described. FIG. 10 is a diagram for explaining a method of calculating the degree of coincidence, and schematically shows a part of the change pattern. As shown in FIGS. 10 (1) and (2), the degree of coincidence calculated in the second embodiment is the degree of coincidence (1) of the vertical axis value (luminance difference value) and the horizontal axis value (time). This is the degree of match indicating the degree of match (2). As (1), in each change pattern, a difference between adjacent signals, a difference between a maximum value and a minimum value within a predetermined time, and the like are calculated, and the difference between the calculated values is set as a matching degree. As (2), in each change pattern, the time difference between the time when the luminance difference value changes to positive and the time when it changes to negative, or the time difference between the time when the maximum value and the time when the minimum value is shown are calculated. The difference between the calculated values is taken as the degree of match. It should be noted that the degree of matching calculated in this way means that both the degree of matching in (1) and the degree of matching in (2) match both change patterns as the value decreases.

  When the degree of coincidence is calculated in this way, the process proceeds to step S48. In step S48, it is determined whether or not the display state of the display D is abnormal based on the degree of matching calculated in step S47. Specifically, as described above, the degree of match of this embodiment means that the smaller the value, the more matched, so when the value of the degree of match is smaller than a predetermined determination value, The change pattern of the brightness difference matches the abnormal change pattern, and it is determined that the display state of the display D is abnormal. Since the degree of coincidence is calculated as (1) and (2), the determination value is set for each degree of coincidence. In addition, it is preferable to determine that both of (1) and (2) are smaller than the determination value. However, depending on the required determination accuracy, (1), ( You may make it determine with matching, when at least one of 2) is smaller than a determination value.

  In the example of (C) and (D) shown in FIG. 9, the change pattern of the luminance difference does not match the abnormal change pattern, and it is determined that the display state of the display D is normal. .

(Specific example 2 of the second embodiment)
Next, a specific example of abnormality determination in the second embodiment, which is different from FIG. 9, will be described with reference to FIG. In FIG. 11, (A), (B), and (C) are the same as FIG. That is, the case of FIG. 11 is also a case where the “AFS OFF” lamp is turned off for a short time. FIG. 11D shows an abnormal change pattern. In order to compare (C) and (D) in FIG. 11, the degree of coincidence between them is calculated. In this example, as the degree of coincidence of the vertical axis values, the degree of coincidence of the luminance difference values ((1) -1) (that is, the difference between (C) and (D)) in the period in which the luminance difference is decreasing, and the luminance The degree of coincidence of the luminance difference value ((1) -2) in the period in which the difference is increasing is calculated, and the degree of coincidence (2) of the horizontal axis value is from the decreasing tendency to the increasing tendency. The degree of match for the period is calculated. Although specific numerical values of these matching degrees are not shown, as can be understood by comparing FIGS. 11C and 11D, the matching degree is a value indicating that both change patterns are well matched. That is, it can be determined that the change pattern of the luminance difference matches the abnormal change pattern well. Therefore, it can be determined that the display state of the display D is abnormal.

  As described above, according to the second embodiment described above, the change pattern of the brightness difference is determined from the image of the display D captured by the camera 10, and the change pattern of the brightness difference is compared with the abnormal change pattern stored in advance. is doing. Therefore, it can be determined whether or not the luminance change of the display device D is an abnormal change. In addition, since a change in luminance occurs even when the indicator D is turned on / off instantaneously, the fact that the instantaneous turn-on / off occurs is reflected in the change pattern of the luminance difference. Therefore, as in the second embodiment, by comparing the change pattern of the luminance difference with the abnormal change pattern, it is automatically determined whether or not the instantaneous turn-on / off generated in the display device D is abnormal. be able to.

(Other specific cases 1)
Furthermore, specific examples will be described. FIG. 12 is a diagram for explaining another specific case 1. FIG. In this case, the simulator 20 temporarily lowers the power supply voltage supplied to the display D from 12V to 4V as a test condition, as shown in FIG. In this case, as a result, as shown in FIG. 12B, the lamp is extinguished for a moment at time t2. Therefore, as shown in FIG. 12C, the luminance difference of the lamp portion area decreases at the time t2 when the lamp is momentarily turned off, and increases at the time t3 when the lamp is turned on again. On the other hand, the switch signal instructing turning on / off of the lamp remains off in this case as shown in FIG. Therefore, although not shown, the difference between the switch signals also remains zero. Therefore, as in the first embodiment, when the degree of correlation between the change pattern of the luminance difference and the change pattern of the difference between the pseudo signals (switch signals) is calculated, the degree of correlation is a value indicating that the two change patterns do not correlate. It becomes. Therefore, it can be determined that the change pattern of the luminance difference is not due to the change of the switch signal, and in this case, it can be determined that the display state is abnormal.

(Other specific case 2)
Next, another specific example 2 will be described. FIG. 13 is a diagram for explaining another specific example 2. In this case, the simulator 20 temporarily shorts the communication line for transmitting information to the display unit D as shown in FIG. In this case, due to this short circuit, as shown in FIG. 13B, the character “brake” is lit for a moment in part of the image on the display D (at time t2). For this reason, the change pattern of the luminance difference in the region including the character portion increases at time t2 and decreases at time t3, as shown in FIG. 13C. In this example, as in the second embodiment, the change pattern of the luminance difference is compared with the abnormal change pattern. Similar to FIG. 11, the degree of coincidence of the luminance difference value when the luminance difference value increases or decreases ( (1) -1, (1) -2) and the degree of coincidence (2) of the period between the decreasing tendency and the increasing tendency of the luminance difference is calculated. In this example, the degree of match is a value indicating that both change patterns match well. That is, it can be determined that the change pattern of the luminance difference matches the abnormal change pattern well. Therefore, it can be determined that the display state of the display D is abnormal.

(Other specific case 3)
Next, another specific example 3 will be described. FIG. 14 is a diagram for explaining another specific example 3. In this case, the display D is a vehicle meter, and a needle 50 that can be turned on and off is shown on the meter. In this case, it is determined whether or not the operation of the needle 50 is normal.

  As an operation example, as shown in FIG. 14A, a normal operation and three types of abnormal operations are illustrated. Normal operation means that the needle 50 operates at a constant speed. Further, as examples of abnormal operations, there are illustrated an abrupt operation that jumps up, an operation that lacks smoothness (in other words, an operation with a non-constant operation speed), and an operation in which the needle vibrates finely. In this case, the luminance difference of the region R shown in (A) is used.

  The luminance difference in the region R is as shown in the leftmost column of FIG. 14B when the meter needle 50 operates normally. The reason why such a change pattern of luminance difference is obtained will be described. First, since the brightness increases when the needle 50 is approached, a positive peak P (+) occurs in the brightness difference. Thereafter, since the time T1 during which the needle 50 passes has a substantially constant luminance, the luminance difference is substantially zero. And if the needle | hook 50 passes the area | region R, since the brightness | luminance of the area | region R will fall, the negative peak P (-) will arise in a brightness | luminance difference. Therefore, when the meter needle 50 operates normally, the luminance difference changes as shown in the leftmost column of FIG.

  On the other hand, when the meter needle 50 is abruptly moved up, the time required for the needle 50 to pass through the region R is shortened, so that the second column from the left in FIG. The change pattern as shown in FIG. Further, when the meter needle 50 operates without smoothness, the interval between the positive peak P (+) and the negative peak P (−) varies, so that the left side of FIG. The change pattern is as shown in the third column. In addition, when the meter needle 50 vibrates finely, the state in which the interval between the positive peak P (+) and the negative peak P (−) is narrow continues, so the rightmost column in FIG. The change pattern as shown in FIG.

  Since change patterns for these abnormalities can be prepared in advance, the degree of coincidence with the abnormal change pattern prepared in advance is calculated, and abnormality determination is performed based on the calculated degree of coincidence. Can be automatically determined as abnormal. As described above, in the present invention, it is possible to determine an abnormal operation of the figure (here, the meter needle 50) displayed on the display D and operating.

(Other specific cases 4)
Next, other specific example 4 will be described. FIG. 15 is a diagram for explaining another specific example 4. In this example, the display state of the lamps (“Startup”, “End”) of the display D is shown, and both are cases where the luminance changes slowly at a constant speed. FIG. 15A shows a temporal change in the display state of each lamp. As shown in (A-1), the case of the lamp “Startup” is a case where the lamp is changed from being turned off to being turned on, and as shown in (A-2), the case of the lamp “End” is changed from being turned on to turned off. It is a changed case. FIG. 15B shows a region where a luminance difference is extracted in this case. As shown in FIG. 15B, in this example, the luminance difference of the display area for one character is extracted. FIG. 15C shows a change pattern of the luminance difference. When the lamp slowly changes from a light-off state to a light-on state at a constant speed, the luminance difference becomes a constant positive value in the changing process, and when the lamp is turned on, the luminance difference becomes zero and constant. Therefore, the change pattern shown in FIG. On the other hand, when the lamp changes slowly from a light-off state to a light-on state at a constant speed, the luminance difference becomes a constant negative value in the changing process, and when the lamp goes off, the luminance difference becomes zero and constant. . Therefore, the change pattern shown in FIG.

  FIG. 15D shows the determination result. Although the abnormal change pattern is not shown, the two cases shown in FIG. 15 are changes in the normal display state and do not match the abnormal change pattern. Therefore, it is determined that the display state is normal. Thus, in the present invention, even when the display state of the display device D changes slowly (both from lighting to turning off and from turning off to lighting), the correct determination is performed even if the change is only once. be able to.

(Other specific cases 5)
Next, other specific example 5 will be described. FIG. 16 is a diagram for explaining another specific example 5. In this example, an abnormality in the display state of a specific character / graphic displayed on the display D is determined. As shown in FIG. 16A, an area slightly larger than the character / graphic is a luminance difference. Is set in the region R from which the. (A-1) is an example of the letter “A”, which indicates that the display is temporarily darkened from the displayed state, and then returns to the original luminance. (A-2) is an example of the figure “◯”, and the change in the display state is the same as in the case of the letter “A”.

  FIG. 16B shows a luminance difference change pattern in this case. A negative peak P (−) occurs corresponding to the temporary darkening from the displayed state. Thereafter, a positive peak P (+) is generated corresponding to the return to the original luminance. In addition, if the change in luminance is the same, the change pattern of the luminance difference is the same change pattern regardless of the shape of the character / graphic. Therefore, as shown in FIG. 16B, the change pattern of the luminance difference is the same for both the character “A” and the graphic “◯”. By comparing this luminance difference change pattern with a pseudo signal difference change pattern or an abnormal change pattern, an abnormality in the display state of a specific character or figure can be determined. Further, according to the present invention, it is possible to determine an abnormality in the display state of the display D without being affected by the shape of characters or figures.

(Other specific cases 6)
Next, another specific example 6 will be described. FIG. 17 is a diagram for explaining another specific example 6. The display example in FIG. 17A is the same as the display example (A-1) in FIG. In FIG. 17, the difference between the right side and the left side is the size of the luminance difference extraction area as shown in FIG. 17B. On the right side, the same area R (3 pixels × 3 pixels) as in FIG. In contrast to the difference extraction area, on the left side, only one pixel of the area R (more specifically, the upper left pixel) is used as the luminance difference extraction area. Although there are differences in the extraction areas as described above, the change pattern of the luminance difference is a change pattern having the same tendency as each other as shown in FIG. Thus, in the present invention, the size of the area from which the luminance difference is extracted can be changed as appropriate.

(Other specific cases 7)
Next, another specific example 7 will be described. FIG. 18 is a diagram for explaining another specific example 7. In the case of FIG. 18, the display state of the meter is an object of abnormality determination, but the entirety is not the object of determination, and the determination object is a meter needle and a lamp provided in the meter. In this case, the determination condition for the meter needle is different from the determination condition for the lamp.

  In the determination condition 1 shown in FIG. 18B, the determination pattern A is applied to the meter needle, and a different determination pattern B is applied to the lamp. Note that these determination patterns use either pseudo signal difference change patterns or abnormal change patterns. Further, in the determination condition 2 shown in FIG. 18C, determination is performed using the determination pattern C for determining using the abnormal change pattern and the change pattern of the difference between the switch signals (pseudo signals) for the meter needle. Two determination patterns D to be applied are applied. On the other hand, for the lamp, determination is performed using a change pattern of a difference between switch signals (pseudo signals) different from determination pattern E and determination pattern D in which determination is performed using an abnormal change pattern different from determination pattern C. Two determination patterns F are applied. In this way, different determination patterns can be applied depending on the region for determining the display state, and a plurality of conditions can be set for determination of one display region.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, The following embodiment is also contained in the technical scope of this invention, and also the summary other than the following is also included. Various modifications can be made without departing from the scope.

  For example, in the first embodiment described above, the time difference between the present time of the positive value and the time difference of the present time of the negative value in the change pattern is calculated, and the correlation is the average value of these two time differences. It is also possible to calculate only the time difference of and to use the degree of correlation as it is.

  Moreover, although the aspect (1st Embodiment) and the aspect (2nd Embodiment) which calculate a degree of coincidence were demonstrated as a comparison of a change pattern, the method of a comparison is not restricted to this. For example, the shapes of two patterns may be compared.

1: Display state evaluation system, 10: Camera, 20: Simulator (pseudo signal generation device), 40: Operation PC (information processing device), 41: Display state test program, 42: Camera operation unit, 43: Simulator operation unit, 44: Image processing unit, 45: Image analysis unit, 46: Image determination unit, 47: Image determination result output unit, 48: Pseudo signal processing unit, 49: Storage unit, 50: Needle, D: Display, R: Area S43: Luminance calculation means, S45: Change pattern determination means, S46 to S48: Display abnormality determination means

Claims (10)

A display state evaluation system for a display device, comprising: a camera that images the display device; and an information processing device that acquires an image captured by the camera and determines an abnormality in the display state of the display device,
The camera images the display over time,
The information processing apparatus includes:
Luminance calculation means for acquiring an image captured by the camera and calculating the luminance of the image over time;
A change pattern determining means for determining a change pattern of a brightness difference based on the brightness calculated by the brightness calculating means over time;
Display abnormality determining means for determining whether there is an abnormality in the display state of the display based on a comparison between the change pattern of the luminance difference determined by the change pattern determining means and a predetermined reference pattern. The display state evaluation system of the display. In claim 1,
The display abnormality evaluation unit uses a preset abnormality change pattern as the reference pattern. In claim 2,
A display state evaluation system for a display device, wherein a plurality of types of abnormality change patterns respectively corresponding to a plurality of types of abnormality in the display state are used as the abnormality change pattern. In claim 1,
Further comprising a pseudo signal generating device that pseudo-generates a display change signal that is a signal for changing a display state of the display and outputs the display change signal to the display;
A display state evaluation system for a display device, wherein the display abnormality determination means uses a pseudo change pattern of display change signals generated as the reference pattern. In any one of Claims 1-4,
The display abnormality determination unit performs the determination based on a comparison between a generation time point of the feature point in the luminance difference change pattern and a generation time point of the feature point in the reference pattern. Evaluation system. In claim 5,
The display state evaluation system for a display device, wherein the feature point is at least one of a rising point and a falling point of a signal in the change pattern. In any one of Claims 2, 3, 5, and 6,
The display abnormality determination unit performs the determination based on a comparison between a change in luminance difference at a predetermined time of the abnormal change pattern and a change in luminance difference at a predetermined time of the change pattern of the luminance difference determined by the change pattern determination unit. A display state evaluation system for a display device. In any one of Claims 1-7,
The luminance calculation means divides the image into a plurality of regions, calculates luminance over time for each region for some or all regions,
The change pattern determining means determines a change pattern of a brightness difference for one or a plurality of preset regions based on the brightness calculated by the brightness calculating means over time. Display state evaluation system. In claim 8,
The change pattern determining means determines a change pattern of luminance difference for each region for a plurality of regions,
The display abnormality determination unit uses a different reference pattern for each luminance difference change pattern as a reference pattern to be compared with the luminance difference change pattern determined by the change pattern determination unit. . In claim 8 or 9,
The display abnormality evaluation unit according to claim 1, wherein the display abnormality determination unit performs determination by comparing a change pattern of one luminance difference with a plurality of different reference patterns.