JP2019211714A - Display device and brightness correction method - Google Patents

Abstract

To provide an art capable of improving the possibility of displaying even when a power supply unit gets troubled.SOLUTION: The display device includes: a correction part for correcting the brightness of a first image signal; a display part; multiple power supply units for supplying current to the display part; and a failure detection part configured to detect a failure of each of the multiple power supply units. The display part displays images on the basis of second image signals which are the first image signals the brightness of which has been corrected by the correction part. The correction part corrects the brightness of the first image signals on the basis of the failure detection result by the failure detection part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to video display.

  Patent Document 1 describes a redundant power supply device including a plurality of power supply units.

JP 2000-284863 A

  When a display device is operated using a plurality of power supply units, there is a possibility that the display device cannot perform display when any of the plurality of power supply units fails.

  Accordingly, the present invention has been made in view of the above points, and an object thereof is to provide a technique capable of improving the possibility of performing display even when a power supply unit has failed. And

  One aspect of the display device according to the present invention displays a video based on a correction unit that corrects the luminance of a first video signal, and a second video signal that is the first video signal whose luminance is corrected by the correction unit. A display unit, a plurality of power supply units that supply current to the display unit, and a failure detection unit that detects a failure of each of the plurality of power supply units, and the correction unit is a failure in the failure detection unit The luminance is corrected based on the detection result.

  Another aspect of the luminance correction method according to the present invention is a luminance correction method for correcting the luminance of a video signal, wherein current is supplied to a display unit that displays an image based on the video signal with the corrected luminance. A first step of detecting a failure of each of the plurality of power supply units, and a second step of correcting the luminance based on a failure detection result in the first step.

  According to the present invention, even when the power supply unit is out of order, the possibility that display can be performed is improved.

It is a figure which shows an example of a structure of a display apparatus. It is a figure for demonstrating an example of operation | movement of a display apparatus. It is a figure which shows an example of a structure of a correction | amendment part. It is a flowchart which shows an example of operation | movement of a correction | amendment part. It is a figure which shows an example of a correspondence table. It is a figure which shows an example of a structure of a correction | amendment part. It is a flowchart which shows an example of operation | movement of a correction | amendment part. It is a figure which shows an example of a correspondence table. It is a flowchart which shows an example of operation | movement of a correction coefficient determination part.

<Embodiment 1>
FIG. 1 is a block diagram illustrating an example of the configuration of the display device 100 according to the present embodiment. The display device 100 is, for example, an LED display device, and includes a plurality of LEDs (Light Emitting Diodes) arranged in a matrix. The display device 100 can display an image by controlling lighting of individual LEDs. Video is a concept that includes both still images and moving images.

  The display device 100 can display at least one of a still image and a moving image. The display device 100 can display various videos. For example, the display device 100 can display a natural image or a moving image such as an animation. The display device 100 is used indoors, for example. The display device 100 may be used outdoors. The display device 100 can be used in various applications. For example, the display device 100 can be used for displaying an advertisement or used for monitoring an indoor person or the like.

  As shown in FIG. 1, the display device 100 includes an input terminal 1, a processing unit 2, a correction unit 3, a drive unit 4, a display unit 5, a failure detection unit 6, and a power supply unit 7. .

  A video signal 200 from the outside of the display device 100 is input to the input terminal 1. For example, a video signal 200 indicating a video having (1920 × 1080) pixels is input to the input terminal 1. The video signal 200 can be said to be video signal data 200 or video data 200.

  The processing unit 2 performs predetermined processing including gamma correction and extraction of an effective area on the video signal 200 input to the input terminal 1. The processing unit 2 outputs the video signal 200 after the predetermined processing to the correction unit 3. The processing unit 2 can be said to be a processing circuit. Hereinafter, the video signal 200 after the predetermined processing is referred to as a video signal 201.

  The correction unit 3 corrects the luminance of the video signal 201 output from the processing unit 2 based on a failure detection result 210 described later in the failure detection unit 6. In other words, the correction unit 3 corrects the luminance of the video based on the video signal 201 (in other words, the video indicated by the video signal 201) based on the failure detection result 210 in the failure detection unit 6. The correction unit 3 can also be said to be a correction circuit. Hereinafter, the video signal 201 whose luminance has been corrected may be referred to as a corrected video signal 202 or a video signal 202. When there is no need to particularly distinguish the video signals 200, 201, and 202, each may be referred to as a video signal without a code.

  The display unit 5 is driven by the driving unit 4 to display a video based on the corrected video signal 202 (in other words, a video indicated by the corrected video signal 202). In the display unit 5, for example, a plurality of pixel units 50 are arranged in a matrix in the video display area. Each pixel unit 50 includes, for example, three LEDs having different emission colors. The three LEDs constituting the pixel unit 50 are configured by a red (R) LED, a green (G) LED, and a blue (B) LED. In the example of FIG. 1, the display unit 5 includes (4 × 4) pixel units 50, that is, 16 pixel units 50. One pixel unit 50 displays one pixel of a video based on the corrected video signal 202. The number and arrangement of the pixel units 50 in the display unit 5 are not limited to the example in FIG.

  The drive unit 4 displays the video based on the corrected video signal 202 on the display unit 5 by driving the display unit 5 based on the corrected video signal 202 output from the correction unit 3. The drive unit 4 can adjust the luminance of the video displayed on the display unit 5 by driving each LED included in the display unit 5 by, for example, a PWM (Pulse Width Modulation) method based on the corrected video signal 202. Is possible. The drive unit 4 can also be said to be a drive circuit.

  FIG. 2 is a diagram for explaining the operation of the drive unit 4. On the upper side of FIG. 2, one frame period 300 of the video signal, which is the basic period of PWM, is shown. An example of a current pulse 400 that the drive unit 4 gives to the LEDs of the display unit 5 is shown at the center and the lower side of FIG. In the center of FIG. 2, a current pulse 400 having a current pulse width 410 with a duty ratio of 100% is shown. 2 shows a current pulse 400 having a current pulse width 410 with a duty ratio of 75%. The current pulse width 410 with a duty ratio of 100% is equal to or less than 300 for one frame period.

  Compared with the case where a current pulse 400 with a duty ratio of 100% is applied to the LED, when the current pulse 400 with a duty ratio of 75% is applied to the LED, the energization time of the LED in one frame period 300 is short. The brightness of becomes smaller. The drive unit 4 adjusts the luminance of the LED by changing the duty ratio of the current pulse 400 within one frame period 300. In addition, when the current pulse 400 with a duty ratio of 75% is applied to the LED as compared with the case where the current pulse 400 with a duty ratio of 100% is applied to the LED, the power-on time of the LED is short, and thus the power consumption of the LED Is reduced.

  Thus, the magnitude of the PWM duty ratio is related to the brightness of the LED and the power consumption of the LED. Therefore, the smaller the luminance of the video signal 202 input to the drive unit 4, the smaller the duty ratio and the lower the power consumption of the LED. On the other hand, the greater the luminance of the video signal 202, the greater the duty ratio and the greater the power consumption of the LED. That is, the power consumption of the LED, the luminance of the LED, and the duty ratio are in a proportional relationship. For example, the power consumption and the luminance when the duty ratio is 75% and the LED is driven by the PWM method are 75% of the power consumption and the luminance when the LED is driven by the PWM method and the duty ratio is 100%. The drive unit 4 controls the duty ratio of the current pulse 400 applied to the LEDs of the display unit 5 according to the luminance of the video signal 202 input thereto.

  Here, one pixel value included in the video signal is composed of, for example, three color components of an R component, a G component, and a B component. Each color component constituting one pixel value is expressed by, for example, 8 bits and has a value in the range of 0 to 255. Therefore, each color component has 256 gradations.

  When the color component having the pixel value included in the video signal 202 input to the driving unit 4 indicates the maximum value (that is, 255), the driving unit 4 generates a current pulse applied to the LED corresponding to the certain color component on the display unit 5. Set the duty ratio to 100%. Thereby, when a color component shows the maximum value, the brightness | luminance of LED corresponding to the said color component becomes the maximum.

  The power supply unit 7 can output the power of the drive unit 4 to the drive unit 4. It can be said that the power supply unit 7 is a power supply circuit. The power supply unit 7 includes a plurality of power supply units 8 that supply current to the display unit 5. In this example, the power supply unit 7 includes four power supply units 8a to 8d. Each of the power supply units 8 a to 8 d supplies a current for the drive unit 4 to drive the display unit 5 to the drive unit 4. The drive unit 4 supplies current supplied from the power supply units 8 a to 8 d to the display unit 5, whereby current is supplied from the power supply units 8 a to 8 d to the display unit 5. For example, commercial power is supplied to the power supply units 8a to 8d. The power supply units 8a to 8d may include a battery.

  In this example, the power supply units 8a to 8d have the same current supply capability. Therefore, the current supply capability of each of the power supply units 8a to 8d is 1/4 of the total current supply capability of the power supply units 8a to 8d. Further, the sum of the current supply capabilities of the power supply units 8a to 8d, in other words, the current supply capability of the entire power supply unit 7 is such that the duty ratio of the current pulse 400 applied to all the LEDs of the display unit 5 is 100%. In addition, the power source unit 7 is set so that the current necessary for the drive unit 4 to drive the display unit 5 can be supplied to the drive unit 4. Note that the number of the plurality of power supply units 8 included in the power supply unit 7 may be less than four, or may be five or more.

  The failure detection unit 6 detects a failure in each of the power supply units 8a to 8d. For example, the failure detection unit 6 monitors the output of the power supply unit 8 and detects a failure of the power supply unit 8 based on the output. If the failure detection unit 6 determines that the power supply unit 8 cannot supply current to the drive unit 4 based on the output of the power supply unit 8, the failure detection unit 6 determines that the power supply unit 8 has failed. The failure detection unit 6 outputs the failure detection result 210 for the power supply units 8 a to 8 d to the correction unit 3. For example, the failure detection unit 6 outputs a failure detection result 210 including the number of failed power supply units 8 among the power supply units 8 a to 8 d to the correction unit 3. The failure detection unit 6 repeatedly performs failure detection of the power supply units 8a to 8d, and outputs a failure detection result 210 to the correction unit 3 each time failure detection is executed. Hereinafter, the number of failed power supply units 8 may be simply referred to as the number of failed units.

  The correction unit 3 performs correction processing for correcting the luminance of the video signal 201 from the processing unit 2 based on the failure detection result 210 output from the failure detection unit 6. Then, the correction unit 3 outputs the corrected video signal 201, that is, the corrected video signal 202 to the drive unit 4. The drive unit 4 displays the video based on the corrected video signal 202 (in other words, the video indicated by the corrected video signal 202) by driving the display unit 5 based on the current (power supply) supplied from the power supply unit 7. This is displayed on part 5.

  FIG. 3 is a block diagram illustrating an example of the configuration of the correction unit 3. As shown in FIG. 3, the correction unit 3 includes a correction coefficient determination unit 31 and a luminance correction unit 32. The correction coefficient determination unit 31 determines a correction coefficient X1 for correcting the luminance of the video signal 201 based on the failure detection result 210 from the failure detection unit 6. The luminance correction unit 32 corrects the luminance of the video signal 201 based on the correction coefficient X1 determined by the correction coefficient determination unit 31. The correction coefficient X1 indicates the rate at which the luminance of the video signal 201 is reduced.

  In this example, the correction unit 3 executes correction processing for each frame of the video signal 201, for example. FIG. 4 is a flowchart showing an example of correction processing for a certain frame. The correction unit 3 executes the correction process shown in FIG. 4 for each frame.

  Hereinafter, one frame of video data included in the video signal may be referred to as a frame image signal. In addition, a video indicated by the frame image signal, that is, a video for one frame may be referred to as a frame image. It can be said that the video for one frame is an image for one frame. In addition, a frame image signal to be described may be referred to as a target frame image signal, and an image indicated by the frame image signal may be referred to as a target frame image.

  As illustrated in FIG. 4, in step s 1, the correction coefficient determination unit 31 of the correction unit 3 acquires the latest failure detection result 210 from the failure detection unit 6. Next, in step s2, the correction coefficient determination unit 31 determines a correction coefficient X1 used for correcting the luminance of the target frame image signal based on the failure detection result 210 acquired in step s1.

  In this example, the correction coefficient determination unit 31 stores a correspondence table 500 in which the value of the number of failures and the value of the correction coefficient X1 are associated with each other. FIG. 5 is a diagram illustrating an example of the correspondence table 500. In the correspondence table 500 shown in FIG. 5, correction coefficients 1.00, 0.75, 0.50, 0.25, and 0.00 are associated with the number of failures 0, 1, 2, 3, and 4, respectively. It has been. The correspondence table 500 is not limited to the example of FIG.

  In step s2, the correction coefficient determination unit 31 determines a correction coefficient X1 used for correcting the luminance of the target frame image signal based on the failure detection result 210 and the correspondence table 500. Specifically, the correction coefficient determination unit 31 specifies the value of the correction coefficient X1 corresponding to the value of the number of failures included in the failure detection result 210 in the correspondence table 500, and uses the specified value as the target frame image signal. The correction coefficient X1 used for correction is output to the luminance correction unit 32.

  After step s2, in step s3, the luminance correction unit 32 corrects the luminance of the target frame image signal based on the correction coefficient X1 from the correction coefficient determination unit 31. Specifically, the luminance correction unit 32 multiplies each of the three color components (R component, G component, and B component) of each pixel value included in the target frame image signal by the correction coefficient X1. Thereby, the luminance of the target frame image signal (in other words, the luminance of the target frame image) is corrected. The target frame image signal whose luminance has been corrected is included in the corrected video signal 202.

  When step s3 is executed, the correction process for the target frame image signal ends. The correction unit 3 performs the correction process shown in FIG. 4 on each frame image signal included in the video signal 201.

  In this example, each of the processing unit 2, the correction unit 3, and the failure detection unit 6 is realized by a hardware circuit that does not require software for realizing its functions. Each of the processing unit 2, the correction unit 3, and the failure detection unit 6 includes, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), and an FPGA (field- It may be composed of at least one of a programmable gate array.

  In addition, at least one of the processing unit 2, the correction unit 3, and the failure detection unit 6 may be realized by a functional block that is realized by a processor executing a program. The processor may include a CPU (Central Processing Unit) or a DSP (Digital Signal Processor). In addition, at least one of the processing unit 2, the correction unit 3, and the failure detection unit 6 is both a functional block realized by the processor executing a program and a hardware circuit that does not require software to realize the function. It may be realized by.

  In the present embodiment, by performing the correction processing as described above, the possibility that the display device 100 can perform display is improved even when the power supply unit 8 fails. This point will be described in detail below.

  For example, consider a case where none of the power supply units 8a to 8d has failed. In this case, the number of failures included in the failure detection result 210 is zero. The correction coefficient determination unit 31 outputs the correction coefficient 1.00 to the luminance correction unit 32 based on the correspondence table 500. The luminance correction unit 32 multiplies each color component of each pixel value included in the frame image signal of the video signal 201 by the correction coefficient X1 from the correction coefficient determination unit 31. Since the correction coefficient X1 is 1.00, the luminance of the corrected video signal 202 is 100% of the luminance of the video signal 201, and the corrected video signal 202 does not change from the video signal 201. Therefore, when the number of faults is 0, the display unit 5 displays an image with the luminance of the video signal 201 output from the processing unit 2, that is, the original luminance. When a color component having a pixel value included in the video signal 201 indicates the maximum value, the same color component having the same pixel value included in the corrected video signal 202 also indicates the maximum value. Therefore, when a color component having a pixel value included in the video signal 201 shows a maximum value, the duty ratio of the current pulse that the driving unit 4 gives to the LED corresponding to the certain color component in the display unit 5 is 100%. .

  Next, consider a case where any one of the power supply units 8a to 8d has failed, that is, the number of failed units is 1. When one of the power supply units 8a to 8d breaks down and current supply is impossible, that is, among the four power supply units 8a to 8d, when there are three power supply units that can supply current, the power supply units 8a to 8d The total power supply capability of 8d is 3/4 (75%) compared to the case where the number of failures is zero. Therefore, when the consumption current in the display unit 5 exceeds 75% of the maximum, the supply current from the power supply unit 7 to the display unit 5 may be insufficient. As a result, the display device 100 may not be able to display.

  In this example, when the number of failures is 1, the correction coefficient determination unit 31 outputs a correction coefficient 0.75 to the luminance correction unit 32 based on the correspondence table 500. The luminance correction unit 32 multiplies each color component of each pixel value included in the frame image signal of the video signal 201 by the correction coefficient X1 from the correction coefficient determination unit 31. Thereby, the luminance of the corrected video signal 202 is 75% of the luminance of the video signal 201. As a result, when a certain color component of the pixel value included in the video signal 201 shows the maximum value, the duty ratio of the current pulse that the driving unit 4 gives to the LED corresponding to the certain color component in the display unit 5 is 75%. It becomes. As described above, since the duty ratio of the current pulse 400 is proportional to the power consumption, the amount of current required for the drive unit 4 to drive the display unit 5 is 75% compared to the case where the number of failures is zero. It becomes. Thereby, the possibility that the current consumption in the display unit 5 exceeds the sum of the current supply capabilities of the power supply units 8a to 8d is reduced. As a result, the possibility that the drive unit 4 cannot drive the display unit 5 can be reduced. Therefore, even if the power supply unit 8 fails, the possibility that the display device 100 can perform display is improved. When the number of failures is 1, the display unit 5 displays an image with the luminance of the video signal 201 output from the processing unit 2, that is, the luminance of 75% of the original luminance.

  When any two of the power supply units 8a to 8d have failed, that is, when the number of failed units is 2, the correction coefficient determination unit 31 outputs the correction coefficient 0.50 to the luminance correction unit 32. Then, the luminance correction unit 32 multiplies each color component of each pixel value included in the frame image signal of the video signal 201 by 0.50. As a result, the luminance of the corrected video signal 202 is 50% of the luminance of the video signal 201. As a result, when a certain color component of the pixel value included in the video signal 201 shows the maximum value, the duty ratio of the current pulse that the driving unit 4 gives to the LED corresponding to the certain color component in the display unit 5 is 50%. It becomes. Therefore, even when the number of failures is 2, the possibility that the current consumption in the display unit 5 exceeds the total current supply capability of the power supply units 8a to 8d is reduced. As a result, even if the power supply unit 8 is out of order, the possibility that the display device 100 can perform display is improved. When the number of failures is 2, the display device 100 can operate while displaying an image with a luminance of 50% of the original luminance.

  When any three of the power supply units 8a to 8d have failed, that is, when the number of failed units is 3, the correction coefficient determination unit 31 outputs the correction coefficient 0.25 to the luminance correction unit 32. Then, the brightness correction unit 32 multiplies each color component of each pixel value included in the frame image signal of the video signal 201 by 0.25. Thereby, the luminance of the corrected video signal 202 is 25% of the luminance of the video signal 201. When the number of failures is 3, the display device 100 can operate while displaying an image with a luminance of 25% of the original luminance.

  When all of the power supply units 8a to 8d have failed, that is, when the number of failures is 4, the correction coefficient determination unit 31 outputs the correction coefficient 0.00 to the luminance correction unit 32. The luminance correction unit 32 multiplies each color component of each pixel value included in the frame image signal of the video signal 201 by 0. As a result, no video signal is input to the drive unit 4 to which no current is supplied from the power supply unit 7. Therefore, the display on the display unit 5 stops, and the operation of the display device 100 stops.

  In the above example, the correction unit 3 corrects the luminance of the video signal 201 according to the number of faults, but may correct the video signal 201 according to whether the power supply unit 8 is faulty. For example, when the number of failures is 0, the correction coefficient X1 is set to 1.00 as described above. If at least one of the plurality of power supply units 8a to 8d has failed, the correction coefficient X1 is set to, for example, 0.25 regardless of the number of failed units. Even in this case, it is possible to reduce the possibility that the display device 100 cannot perform display compared to the case where the luminance of the video signal 201 is not corrected.

  As described above, in the display device 100 according to the present embodiment, the correction unit 3 corrects the luminance of the video signal 201 based on the failure detection result 210 in the failure detection unit 6, so that the power supply unit 8 fails. Even in this case, the possibility that the display device 100 can perform display can be improved.

  For example, when the display device 100 is used for monitoring an indoor person or the like, the display device 100 may be operated for 24 hours. In the present embodiment, even if the power supply unit 8 is out of order, the operation of the display device 100 can be continued, so that monitoring of people and the like can be continued.

  Further, in the present embodiment, when a part of the plurality of power supply units 8 breaks down, it is possible to reduce the possibility that the power supply unit 8 that operates normally is excessively loaded. Therefore, even when the display device 100 is used in a system such as a monitoring system, it is possible to reduce the possibility that the power supply unit 8 is overloaded and the entire system stops.

  Further, as in this example, when the number of failures is included in the failure detection result 210, the correction unit 3 can correct the luminance of the video signal 201 according to the number of failures. The possibility of becoming impossible can be reduced more reliably.

<Embodiment 2>
In the display device 100 according to Embodiment 1 described above, when the number of failures is 1 or more, the luminance of the video displayed on the display unit 5 is the original luminance regardless of the content of the video indicated by the video signal 200. Of 75% or less.

  On the other hand, all pixels constituting the frame image of the video signal 201 may not have the maximum luminance. In this case, there is a possibility that the display device 100 operates in a state where the suppliable current of the power supply units 8 a to 8 d has a margin with respect to the current consumption of the display unit 5.

  In the present embodiment, even if the power supply unit 8 is out of order, the possibility that an image can be displayed is improved, and further, the amount of decrease in luminance of the image to be displayed can be reduced. Such a display device 100 will be described.

  The display device 100 according to the present embodiment is different from the display device 100 according to the first embodiment described above in the configuration of the correction unit 3. FIG. 6 is a diagram illustrating an example of the configuration of the correction unit 3 according to the present embodiment. As illustrated in FIG. 6, the correction unit 3 includes a luminance information acquisition unit 33, a correction coefficient determination unit 34, and a luminance correction unit 35.

  In the present embodiment, the correction unit 3 performs a correction process for correcting the luminance of the video signal 201 based on the failure detection result 210 and the luminance information of the video signal 201. FIG. 7 is a flowchart illustrating an example of correction processing according to the present embodiment.

  In step s11, the luminance information acquisition unit 33 of the correction unit 3 acquires luminance information from the video signal 201. As the luminance information, for example, an average luminance rate is adopted. The average luminance rate is information regarding the average luminance of the video signal 201. Specifically, the average luminance rate means the ratio of the average luminance of the frame image indicated by the frame image signal included in the video signal 201 to the maximum value of the range that the average luminance can take. In step s11, the luminance information acquisition unit 33 obtains an average luminance rate for the target frame image signal of the video signal 201.

  Here, the total number of pixels of the target frame image is num. And the R component, G component, and B which comprise the pixel value of the i (1 <= i <= num) th pixel when the number from 1 to num is provided with respect to the some pixel which comprises an object frame image The components are ZRi, ZGi, and ZBi, respectively. The average luminance Y1 of the target frame image is expressed by the following formula (1).

  As described above, each of the R component, G component, and B component constituting the pixel value has 256 gradations. Therefore, the maximum value of the range that the average luminance Y1 can take is 255. Therefore, the average luminance rate Y2 is expressed by the following formula (2).

  In step s11, the luminance information acquisition unit 33 calculates the average luminance rate Y2 for the target frame image using the equations (1) and (2), and outputs the calculated average luminance rate Y2 to the correction coefficient determination unit 34. .

  After step s11, in step s12, the correction coefficient determination unit 34 acquires the latest failure detection result 210 from the failure detection unit 6. In step s13, the correction coefficient determination unit 34 determines the correction coefficient X1 based on the acquired failure detection result 210 and the luminance information acquired by the luminance information acquisition unit 33. In this example, the correction coefficient determination unit 34 determines the correction coefficient X1 based on the failure detection result 210 and the average luminance rate Y2.

  In step s 13, first, the correction coefficient determination unit 34 obtains a power supply operation rate indicating the operation rate of the power supply unit 8 based on the failure detection result 210. For example, the correction coefficient determination unit 34 stores a correspondence table 600 in which values of the number of failures and values of power supply operating rates are associated with each other. FIG. 8 is a diagram showing an example of the correspondence table 600. In the correspondence table 600 shown in FIG. 8, the power availability ratios 1.00, 0.75, 0.50, 0.25, and 0.00 correspond to the number of failures 0, 1, 2, 3, and 4, respectively. It is attached. The correspondence table 600 is not limited to the example of FIG.

  In step s13, the correction coefficient determination unit 34 obtains the current power supply operation rate based on the failure detection result 210 and the correspondence table 600. Specifically, the correction coefficient determination unit 34 specifies the value of the power supply operation rate corresponding to the value of the number of failures included in the failure detection result 210 in the correspondence table 600. Then, the correction coefficient determination unit 34 sets the specified value as the current power supply operation rate Y3.

  In step s13, when the current power supply availability Y3 is obtained, the correction coefficient determination unit 34 performs a determination process for determining the correction coefficient X1 based on the obtained power supply availability Y3 and the average luminance rate Y2. FIG. 9 is a flowchart showing an example of the determination process executed in step s13.

  As shown in FIG. 9, in step s21, the correction coefficient determination unit 34 determines whether or not the power supply operation rate Y3 is larger than the average luminance rate Y2. If YES is determined in step s21, the correction coefficient determination unit 34 sets the correction coefficient X1 to 1.00 in step s22. When the power supply operation rate Y3 is larger than the average luminance rate Y2, there is a possibility that the current supply amount of the power supply units 8a to 8d is sufficient without reducing the luminance of the video signal 201. Therefore, the correction coefficient 1 is set to 1.00.

  On the other hand, if NO is determined in step s21, the correction coefficient determination unit 34 determines the correction coefficient X1 using the following equation (3) in step s23.

  As shown in Expression (3), a value obtained by dividing the power supply operating rate Y3 by the average luminance rate Y2 is set as the correction coefficient X1. When the average luminance rate Y2 is equal to or higher than the power supply operating rate Y3, the current supply amount of the power supply units 8a to 8d may be insufficient unless the luminance of the video signal 201 is reduced. By setting X1 = Y3 / Y2, it is possible to reduce the amount of decrease in luminance of the video signal 201 while reducing the possibility that the current supply amount of the power supply units 8a to 8d will be insufficient.

  When the determination process ends in step s13, in step s14, the luminance correction unit 35 uses the correction coefficient X1 determined by the correction coefficient determination unit 34 in the same manner as described above, and each color component of each pixel value of the target frame image signal. Is multiplied to correct the luminance of the target frame image.

  When step s14 is executed, the correction process for the target frame image signal ends. The correction unit 3 performs the correction process shown in FIG. 7 on each frame image signal included in the video signal 201.

  In step s21 of the determination process, it may be determined whether or not the power supply operation rate Y3 is equal to or higher than the average luminance rate Y2. If YES is determined in step s21, step s22 is executed, and if NO is determined in step s21, step s23 is executed.

  Further, the luminance information acquired by the luminance information acquisition unit 33 may be information other than the average luminance rate as long as it is information relating to the luminance of the video signal 201. The method by which the correction coefficient determination unit 34 determines the correction coefficient X1 based on the failure detection result 210 and the luminance information is not limited to the above example.

  As described above, the display device 100 according to the present embodiment corrects the luminance of the video signal 201 based on the failure detection result 210 and the luminance information of the video signal 201, so that the power supply unit 8 has failed. Even in such a case, the possibility of display can be improved, and the amount of reduction in luminance of the displayed video can be reduced. Therefore, for example, when the video indicated by the video signal 201 is dark, it is possible to reduce the possibility that a situation occurs in which the display video is further darkened and the visibility of the display video is reduced.

  In the above example, the display device 100 is an LED display device, but other display devices may be used. That is, the display element of the display unit 5 may be other than the LED.

  Further, within the scope of the invention, the present invention can be freely combined with each other, or can be appropriately modified or omitted.

  3 correction unit, 5 display unit, 6 failure detection unit, 8, 8a to 8d power supply unit, 100 display device, 201, 202 video signal.

Claims (5)

A correction unit for correcting the luminance of the first video signal;
A display unit for displaying a video based on a second video signal that is the first video signal with the luminance corrected by the correction unit;
A plurality of power supply units for supplying current to the display unit;
A failure detection unit for detecting a failure of each of the plurality of power supply units,
The said correction | amendment part is a display apparatus which correct | amends the said brightness | luminance based on the failure detection result in the said failure detection part. The display device according to claim 1,
The failure detection result includes a display device including the number of failed power supply units among the plurality of power supply units. A display device according to any one of claims 1 and 2,
The correction unit is
Obtaining luminance information from the first video signal;
A display device that corrects the luminance based on the failure detection result and the luminance information. The display device according to claim 3,
The display device, wherein the luminance information includes information related to an average luminance of the first video signal. A luminance correction method for correcting the luminance of a video signal,
A first step of detecting a failure of each of a plurality of power supply units that supply current to a display unit that displays an image based on the image signal with the corrected brightness;
A luminance correction method comprising: a second step of correcting the luminance based on a failure detection result in the first step.

Images