Image display control device, image display system, and image display control method

Abstract

An image display control device includes a luminance control unit that generates backlight control information for controlling a plurality of light sources, a pixel compensation unit that corrects an input image on the basis of the backlight control information, and an abnormality detection unit. The abnormality detection unit detects an abnormality in the luminance control unit on the basis of whether second statistical data of luminance values of each light source included in the backlight control information is included in a range between an upper limit value and a lower limit value determined by first statistical data of pixel values included in first image information indicating the input image. Therefore, the abnormality of the brightness control part installed on the image display control device with the local dimming function can be detected.

Description

Technical Field

[0001] The invention relates to an image display control device, an image display system and an image display control method. Background Art

[0002] Recently, in a display control device for displaying an image on a display device, local dimming for adjusting the brightness of each light source according to the brightness of an input image is well known, wherein the display device has a backlight (backlight) in which a plurality of light sources are arranged in an array. By local dimming, contrast can be improved and power consumption can be reduced.

[0003] A backlight unit is known that includes a plurality of LED elements and a plurality of light sensors for detecting the luminance of each LED element, wherein the light emission of the plurality of LED elements can be independently controlled. In such a backlight unit, when any light sensor fails, other light sensors can be used to replace the failed light sensor to estimate the luminance of the LED element corresponding to the failed light sensor (for example, see patent document 1).

[0004] In addition, in the event that a failure occurs in any of the multiple light-emitting areas included in a light source for illuminating a liquid crystal panel, a method for moving an image in a display area corresponding to the failed light-emitting area to a display area corresponding to a normal light-emitting area is also well known (for example, see patent document 2).

[0005] [Reference document]

[0006] [Patent document]

[0007] [Patent Document 1] (Japan) Patent Publication No. 2014-182291

[0008] [Patent Document 2] (Japan) Patent Publication No. 2018-159796 Summary of the invention

[0009] [Technical issues to be solved]

[0010] For example, an image display control device that performs local dimming includes a brightness control unit that adjusts the brightness of multiple light sources according to the brightness of an input image and a pixel compensation unit that adjusts the brightness of the image according to the brightness of the adjusted light sources. If an abnormality occurs in the brightness control unit, the brightness or color tone of the image displayed on the display device may change.

[0011] For example, part of the abnormality of the brightness control unit can be detected by CRC (Cyclic Redundancy Check) verification, etc., wherein the CRC verification is used to detect the abnormality of the communication between the brightness control unit and the driver that drives the light source. However, in the case of displaying an image (video) in a state where each light source is emitting light but not turned off, it is difficult to confirm whether the brightness output value from the brightness control unit to the driver is normal (in a normal state). For example, by implementing the same circuit in parallel and comparing the two outputs, the abnormality of the brightness output value can be determined. However, in this case, the circuit scale increases, and the cost of the image display control device will also increase accordingly.

[0012] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to detect abnormality in a brightness control unit for controlling the brightness of a plurality of light sources mounted on an image display control device having a local dimming function.

[0013] [Technical solution]

[0014] In one embodiment of the present invention, an image display control device is an image display control device with a local dimming function, comprising:

[0015] a brightness control unit that generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image;

[0016] a pixel compensation unit that corrects the pixel values ​​included in the first image information according to the brightness of the plurality of light sources to generate second image information representing an output image;

[0017] a first statistics acquisition unit, which acquires first statistical data of pixel values ​​included in the first image information;

[0018] a second statistics acquisition unit, which acquires second statistical data of the luminance value of each light source included in the backlight control information; and

[0019] The abnormality detection unit detects abnormality of the brightness control unit based on whether the second statistical data is included in a range between an upper limit value and a lower limit value determined by the first statistical data.

[0020] [Beneficial Effects]

[0021] According to the disclosed technology, it is possible to detect abnormality in a luminance control unit for controlling the luminance of a plurality of light sources mounted on an image display control device having a local dimming function. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] [ Figure 1 ] is a block diagram showing an example of an image display system according to the first embodiment.

[0023] [ Figure 2 ]express Figure 1 A block diagram of an example of a display controller.

[0024] [ Figure 3 ]express Figure 2 A block diagram of an example of a local dimming unit.

[0025] [ Figure 4 ]Depend on Figure 3 A schematic diagram of an example of how a brightness control unit controls the brightness of a backlight.

[0026] [ Figure 5 ]Depend on Figure 3 A schematic diagram of an example of luminance distribution is generated by the luminance distribution calculation unit.

[0027] [ Figure 6 ]Depend on Figure 3 A schematic diagram of an example of how the RGB correction unit corrects the brightness of an image.

[0028] [ Figure 7 ]Depend on Figure 3 A schematic diagram of an example of statistical information acquired by the input color statistics acquisition unit and the output luminance statistics acquisition unit.

[0029] [ Figure 8 ] is used for Figure 3 A schematic diagram of an example of a threshold value for determining an abnormality in a brightness control unit.

[0030] [ Fig. 9 ] indicates that Figure 3 A flowchart of an example of a process in which a processor determines an abnormality in a brightness control unit.

[0031] [ Fig.10 ]express Fig. 9 Flowchart of an example of the processing of step S80.

[0032] [ Fig.11 ] is a block diagram showing an example of a display controller according to the second embodiment.

[0033] [ Fig.12 ] indicates that Fig.11 A block diagram of an example of an input color statistics acquisition unit, an output luminance statistics acquisition unit, and an output color statistics acquisition unit connected to a local dimming unit.

[0034] [ Fig.13 ]Depend on Fig.12 Schematic diagram of an example of an input color statistics acquisition unit, an output luminance statistics acquisition unit, and statistical data acquired by the output color statistics acquisition unit.

[0035] [ Fig.14 ] is used for Fig.12 A schematic diagram of an example of a threshold value for determining an abnormality in a brightness control unit.

[0036] [ Fig.15 ] indicates that Fig.12 A flowchart of an example of a process in which a processor determines an abnormality in a brightness control unit. DETAILED DESCRIPTION

[0037] The following describes the implementation mode with reference to the accompanying drawings. In the following, image data is sometimes referred to as image.

[0038] (First embodiment)

[0039] Figure 1 This is a block diagram showing an example of the image display system according to the first embodiment. Figure 1 The illustrated image display system 1 has a head unit 10 , a serializer 20 , a deserializer 30 , a display controller 40 , and a display device 70 including a display 50 and a backlight 60 .

[0040] The head unit 10 generates an image displayed on the display 50. In addition, the head unit 10 also outputs image data 10a and control information 10b corresponding to the generated image to the serializer 20. For example, the control information 10b contains information for controlling when the image is displayed on the display 50. For example, the image data 10a may include an overlay image such as an icon or the like overlaid on the original image.

[0041] The serializer 20 converts the image data 10a and the control information 10b output from the head unit 10 into serial data 20a. The serializer 20 transmits the serial data 20a obtained by the conversion to the deserializer 30 via one video connection (transmission line). Although there is no particular limitation, the transmission and reception of the serial data 20a via the video connection can be performed using an interface such as LVDS (Low Voltage Differential Signaling) and APIX (Automotive Pixel Link: registered trademark).

[0042] The deserializer 30 converts the serial data 20a received via the video connection into image data 30a and control information 30b. The image data 30a and the control information 30b correspond to the original image data 10a and the control information 10b output by the head unit 10, respectively. In addition, the deserializer 30 also outputs the image data 30a and the control information 30b obtained by the conversion to the display controller 40.

[0043] The display controller 40 outputs information 40a including image data representing an image displayed on the display 50 to the display 50 based on the image data 30a and the control information 30b received from the deserializer 30. In addition, the display controller 40 outputs information 40b for controlling the brightness of the backlight 60 to the backlight 60 based on the image data 30a and the control information 30b. The display controller 40 is an example of an image display control device.

[0044] Although not particularly limited, image data input to and output from the display controller 40 include pixel values ​​of red (R), green (G), and blue (B) pixels representing an RGB color space.

[0045] The display 50 is, for example, a liquid crystal display including a liquid crystal shutter and a color filter, wherein the liquid crystal shutter is used to adjust the transmittance of the light irradiated from the backlight 60, and the color filter is used to receive the light transmitted from the liquid crystal shutter. It should be noted that the display 50 may also be a display other than a liquid crystal display, as long as the transmittance of the light irradiated from the backlight 60 can be adjusted. The display 50 is an example of a display unit.

[0046] The backlight 60 includes a plurality of LED (Light Emitting Diode) light sources arranged in a matrix, and is arranged opposite to the surface on the opposite side of the image display surface of the display 50. Hereinafter, the irradiation area of ​​light corresponding to each LED light source in the display 50 is referred to as an LED area. It should be noted that, instead of the plurality of LED light sources arranged in a matrix, the backlight 60 may also have other plurality of light sources with adjustable brightness.

[0047] For example, the image display system 1 may be installed in a vehicle. In this case, the display device 70 may be used, for example, to display an instrument cluster or a central information display (CID) on a dashboard. Alternatively, the display device 70 may be used as a head-up display that projects an image onto a windshield.

[0048] The image display system 1 installed in the vehicle is designed to meet the requirements of ASIL (Automotive Safety Integrity Level). It should be noted that the image display system 1 equipped with a backlight and having a local dimming function is not limited to use in vehicles, but can also be used in other image display systems such as digital signage.

[0049] For example, the display controller 40 performs a local dimming process for adjusting the brightness of a plurality of LED backlights independently of each other according to the brightness (e.g., pixel value) of an image displayed on the display 50. It should be noted that in the local dimming process, the display controller 40 performs a compensation control for suppressing an increase in the brightness of the surrounding image caused by light leakage around the position of the LED backlight that is lit. By means of the local dimming process, the power consumption of the backlight 60 can be suppressed, and the reproducibility of the black color of the image displayed on the display 50 can be improved.

[0050] Figure 2 Yes means Figure 1 The display controller 40 is a block diagram of an example of a display controller 40. The display controller 40 is, for example, a semiconductor integrated circuit, and includes a display engine 200, a memory 300, and a processor 400 that are interconnected via a bus 500.

[0051] The display engine 200 includes an image input unit 210, a memory 220, a deformation unit 230, an input color statistics acquisition unit 240, a local dimming unit 250, an output luminance statistics acquisition unit 260, an image output unit 270, and a register interface 280. The local dimming unit 250 includes a luminance control unit 251 and a pixel compensation unit 252. For example, each element (each functional unit) of the display engine 200 works (operates) based on the control from the processor 400. Although not particularly limited, the display engine 200 performs processing of image data representing an RGB color space.

[0052] The image input unit 210 receives the Figure 1 The deformation unit 230 receives the image data (for example, the input image in frames) sent by the deserializer 30, and stores the received image data in the memory 220. The deformation unit 230 uses the image data stored in the memory 220 to perform distortion correction (correction) processing to obtain the image data in the memory 220. Figure 1 The distortion-free image is displayed on the display 50. The deformation unit 230 also outputs the distortion-corrected input image data VIN to the local dimming unit 250.

[0053] The input color statistics acquisition unit 240 sequentially acquires the average of the pixel values ​​of one screen (one frame) included in the input image data VIN input from the deformation unit 230 to the local dimming unit 250, that is, the average input video brightness AIVB. For example, the input color statistics acquisition unit 240 acquires the average input video brightness AIVB by calculation. The average input video brightness AIVB is an example of the first statistical data. The input image data VIN is an example of the first image information, and the input color statistics acquisition unit 240 is an example of the first statistics acquisition unit.

[0054] The input color statistics acquisition unit 240 outputs the acquired average input video brightness AIVB to the processor 400 via the register interface 280 and the bus 500. It should be noted that the input color statistics acquisition unit 240 may have a storage unit such as a buffer for holding the average input video brightness AIVB. In this case, the average input video brightness AIVB held in the storage unit can be read by the processor 400.

[0055] The display controller 40 has a local dimming function. That is, the luminance control unit 251 of the local dimming unit 250 generates a luminance control unit for adjusting the local dimming function according to the input image data VIN. Figure 1 The backlight control signal BLCNT is generated to adjust the brightness of the backlight 60 , and the generated backlight control signal BLCNT is output to the backlight 60 .

[0056] In addition, the brightness control unit 251 also outputs the brightness information LINF indicating the brightness of each of the plurality of LED light sources of the backlight 60 to the output brightness statistics acquisition unit 260. For example, the brightness information LINF may include the same information as the information included in the backlight control signal BLCNT indicating the brightness of each of the plurality of LED light sources, or may be the backlight control signal BLCNT itself. The brightness adjustment method of the backlight 60 performed by the brightness control unit 251 will be described below in conjunction with Figure 4 The luminance information LINF and the backlight control signal BLCNT are examples of the backlight control information.

[0057] The pixel compensation unit 252 of the local dimming unit 250 corrects the pixel value (for example, brightness value) of the input image data VIN according to the brightness of the backlight 60 adjusted by the brightness control unit 251, and outputs it to the image output unit 270 as the output image data VOUT. The output image data VOUT is an example of the second image information. For example, the pixel compensation unit 252 performs correction to make the pixel value of the area with higher brightness of the backlight 60 relatively smaller and to make the pixel value of the area with lower brightness of the backlight 60 relatively larger. At this time, the pixel compensation unit 252 corrects the pixel value by taking into account the light leakage around each LED light source. The image correction method performed by the local dimming unit 250 will be described below in conjunction with Figure 5 and Figure 6 Provide explanation.

[0058] The output luminance statistics acquisition unit 260 sequentially acquires the luminance information LINF output from the local dimming unit 250 for each screen (frame). The output luminance statistics acquisition unit 260 acquires the average luminance of each LED light source contained in the luminance information LINF, that is, the average backlight luminance ABB. For example, the output luminance statistics acquisition unit 260 acquires the average backlight luminance ABB by calculation. The average backlight luminance ABB is an example of the second statistical data. The output color statistics acquisition unit 290 is an example of the second statistical acquisition unit.

[0059] The output luminance statistics acquisition unit 260 outputs the acquired average backlight luminance ABB to the processor 400 via the register interface 280 and the bus 500. It should be noted that the output luminance statistics acquisition unit 260 may have a storage unit such as a buffer for holding the average backlight luminance ABB. In this case, the average backlight luminance held in the storage unit can be read by the processor 400.

[0060] The image output unit 270 transmits the output image data VOUT (eg, the output image in units of frames) received from the local dimming unit 250 to the local dimming unit 250. Figure 1 The display 50 is configured to display an image.

[0061] The memory 300 holds, for example, an image display control program executed by the processor 400, data used by the image display control program, etc. The processor 400 is a controller such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). For example, the processor 400 controls the operation of the display controller 40 by executing the image display control program.

[0062] In addition, the processor 400 detects an abnormality of the brightness control unit 251 based on the average input video brightness AIVB obtained by the input color statistics acquisition unit 240 and the average backlight brightness ABB obtained by the output brightness statistics acquisition unit 260, for example, by executing the image display control program. The functional unit in the processor 400 that detects an abnormality of the brightness control unit 251 is an example of an abnormality detection unit. It should be noted that the processor 400 can make the detection of an abnormality easier or more difficult based on threshold information received from outside the processor 400. The threshold information can be supplied from outside the image display system 1.

[0063] It should be noted that the processor 400 suppresses the abnormality detection processing of the brightness control unit 251 when one or both of the average input video brightness AIVB from the input color statistics acquisition unit 240 and the average backlight brightness ABB from the output brightness statistics acquisition unit 260 have not been obtained. The abnormality detection processing of the brightness control unit 251 will be described below in conjunction with Figures 7 to 10 Provide explanation.

[0064] Figure 3 Yes means Figure 2 A block diagram of an example of a local dimming unit 250. Figure 3 In, yes Figure 2 The description (illustration) of the register interface 280 and the bus 500 is omitted. The pixel compensation unit 252 of the local dimming unit 250 includes a luminance distribution calculation unit 253 , an RGB correction unit 254 , and a saturation processing unit 255 .

[0065] The luminance distribution calculation unit 253 receives the luminance information LINF indicating the luminance of each LED light source and the luminance distribution function when only one LED light source is turned on, namely, LSF (Lighting Spread Function), received from the luminance control unit 251. The luminance distribution calculation unit 253 generates the luminance distribution of the backlight 60 taking into account the light leakage around each LED light source according to the luminance information LINF and the luminance distribution function LSF, and outputs the information indicating the generated luminance distribution to the RGB correction unit 254. For example, the luminance distribution generated by the luminance distribution calculation unit 253 indicates the distribution of the luminance value of the backlight 60 at each pixel in all the pixels of the display 50, and is expressed as a value greater than 0 and less than or equal to 1. Here, the luminance value of the luminance distribution is closer to 0 as it is lower, and closer to 1 as it is higher.

[0066] The RGB correction unit uses formula (1) to calculate the gain (Gain) of the pixel value applied to each pixel of the display 50 according to the luminance distribution (luminance value). As can be seen from formula (1), the minimum value of the gain is 1, and the maximum value of the gain is infinite. Here, infinity refers to the maximum value that can be represented by the number of bits representing the gain.

[0067] Gain = 1 / brightness distribution…(1)

[0068] In addition, the RGB correction unit 254 also uses formulas (2-1), (2-2), and (2-3) to multiply the pixel value of each color component of each pixel included in the input image data VIN by the gain calculated by formula (1), thereby calculating the correction value of the pixel value of each color component. The symbol R in formula (2-1) represents the pixel value of the red pixel. The symbol G in formula (3-2) represents the pixel value of the green pixel. The symbol B in formula (2-3) represents the pixel value of the blue pixel.

[0069] R=R×Gain…(2-1)

[0070] G=G×Gain…(2-2)

[0071] B=B×Gain…(2-3)

[0072] For example, the pixel value of each color component of each pixel of the input image data VIN is normalized to be greater than 0 and less than 1. Figure 2 When the image input unit 210 inputs 8-bit image data (0 to 255) for each pixel, the maximum value 255 in the input image data VIN becomes 1. The RGB correction unit 254 outputs the calculated correction value of the pixel value to the saturation processing unit 255 as image data VC.

[0073] For example, each pixel value of the image data VC is represented by 12 bits, the minimum value is 0, and the maximum value is 4095. It should be noted that each pixel value of the image data VC can also be represented by a number of bits other than 12 bits (for example, 10 bits, 14 bits, etc.). In addition, if each pixel value of the input image data VIN is represented by 8 bits (0 to 255), each pixel value of the image data VC can also be represented by 20 bits (0 to 1048576).

[0074] The saturation processing unit 255 sets the maximum pixel value of the image data VC to 1 and normalizes the other pixel values ​​to be greater than 0 and less than 1, thereby generating output image data VOUT. The saturation processing unit 255 also outputs the generated output image data VOUT to the display 50 .

[0075] Figure 4 Is Figure 3 Schematic diagram of an example of how the brightness control unit 251 controls the brightness of the backlight 60. For example, the brightness control unit 251 obtains the maximum value ZMAX of the pixel value and the average value ZAVE of the pixel value in the input image data VIN corresponding to the input image for each area corresponding to the LED area of ​​the backlight 60. Here, the maximum value ZMAX and the average value ZAVE are obtained based on the pixel values ​​of the red pixel, the green pixel, and the blue pixel corresponding to each LED area, and the maximum value is "1" and the minimum value is "0".

[0076] After that, the brightness control unit 251 calculates the brightness of each LED area using formula (3), and outputs the backlight control signal BLCNT indicating the brightness obtained by the calculation to the backlight 60, and outputs the brightness information LINF to the pixel compensation unit 252 and the output brightness statistics acquisition unit 260. In formula (3), the symbol α is a parameter for adjusting the brightness, and is set to be greater than 0 and less than 1, for example. For example, when the brightness adjustment parameter α is 0.5, the maximum value ZMAX and the average value ZAVE are mixed in a manner of 50% each. For example, the brightness adjustment parameter α can be set by the user using the image display system 1, or can be set from the outside.

[0077] Luminance of each LED area = α×ZMAX+(1-α)×ZAVE…(3)

[0078] Figure 5 Is Figure 3 The luminance distribution calculation unit 253 generates a schematic diagram of an example of luminance distribution. The light emitted from each LED light source spreads (diffuses) to the adjacent LED area, and therefore, the luminance distribution is obtained by considering the spread (bleeding) of light. The luminance distribution calculation unit 253 obtains the luminance distribution by convolutionally integrating the luminance information LINF of each LED area of ​​the backlight 60 and the luminance distribution function LSF.

[0079] Figure 5 In the formula shown, the symbol x represents the horizontal coordinate for identifying the LED area, and the symbol y represents the vertical coordinate for identifying the LED area. bl(x', y') represents the brightness of each LED area, and lsf(x-x', y-y') represents the brightness distribution function LSF. Figure 5 The square brackets in show the situation where the luminance distribution when two LED light sources are lit and the other LED light sources are not lit is calculated by convolution integral.

[0080] Figure 6 Is Figure 3 Schematic diagram of an example of how the RGB correction unit 254 corrects the brightness of an image. When the input image data VIN is output as the output image data VOUT without being corrected according to the brightness distribution, the brightness of the image displayed on the display 50 is the product of the brightness of the input image and the brightness of the backlight, so an image with correct brightness cannot be displayed.

[0081] To this end, the RGB correction unit 254 calculates the gain of each pixel (each of RGB) of the input image data VIN using formula (1), and multiplies the calculated gain by the pixel value of the input image data VIN to correct the pixel value, thereby offsetting the brightness of the backlight 60. Therefore, the brightness of the image displayed on the display 50 can be correctly set using the light from the backlight 60, wherein the brightness of each LED light source of the backlight 60 is individually (separately) adjusted according to the brightness of the image.

[0082] It should be noted that in Figure 3 In the saturation processing of the pixel value performed by the saturation processing unit 255, the maximum value Vmax of all the pixel values ​​included in the image data VC is set to the pixel value 1 of the output image data VOUT.

[0083] Figure 7 Is Figure 3 Schematic diagram of an example of statistical information acquired by the input color statistics acquisition unit 240 and the output luminance statistics acquisition unit 260.

[0084] The input color statistics acquisition unit 240 obtains the maximum value MAX of the pixel value (the maximum value of the pixel value of the red pixel, the pixel value of the green pixel, and the pixel value of the blue pixel) for each pixel in all pixels of the input image data VIN of each frame. Then, the input color statistics acquisition unit 240 obtains the average input video brightness AIVB by dividing the sum (total) of the maximum values ​​MAX of all pixels by the number of all pixels. Figure 7 Calculation examples of the input color statistics acquisition section 240 when the number of pixels is “4” (2 pixels horizontally and 2 pixels vertically) are shown in FIG.

[0085] The output luminance statistics acquisition unit 260 acquires the luminance (set luminance) of each LED light source of the backlight 60 according to the luminance information LINF received from the luminance control unit 251. Then, the output luminance statistics acquisition unit 260 acquires the average backlight luminance ABB by dividing the sum of the acquired luminances of each LED light source by the total number of LED light sources. Figure 7 Calculation examples of the output luminance statistics acquisition unit 260 when the number of LED light sources is 10 (5 horizontally and 2 vertically) are shown in FIG.

[0086] Figure 8 It is used to determine Figure 3 Schematic diagram of an example of an abnormal threshold value of the brightness control unit 251. The processor 400 determines whether the brightness of the backlight 60 is abnormal according to the input image data VIN of each frame. For example, the processor 400 obtains the upper and lower threshold values ​​of the brightness range of the normal backlight 60 based on the average input video brightness AIVB of the determination object (target) frame obtained by the input color statistics acquisition unit 240. The upper threshold value is an example of an upper limit value, and the lower threshold value is an example of a lower limit value.

[0087] For example, when the pixel value of at least one pixel in the pixel area corresponding to the illumination area of ​​one LED light source, i.e., the LED area, is "1" (i.e., white), the maximum value ZMAX of formula (3) is "1". When the maximum value ZMAX in formula (3) is "1" and the brightness adjustment parameter α is greater than "0", the brightness of the LED area obtained by formula (3) is higher than the average value ZAVE of the pixel values ​​of the pixel area corresponding to the LED area, which is the upper limit. For this reason, by applying this condition (ZMAX = "1") to formula (3) and using the average input video brightness AIVB instead of the average value ZAVE of the pixel values ​​corresponding to the LED area in formula (3), the upper limit threshold can be obtained by formula (4).

[0088] Upper threshold = α + (1-α) × AIVB… (4)

[0089] In addition, when the brightness adjustment parameter α is "0", the brightness of each LED area shown in formula (3) is the average value ZAVE. Therefore, by applying this condition (α = "0") to formula (3) and using the average input video brightness AIVB instead of the average value ZAVE of the pixel values ​​corresponding to the LED area in formula (3), the lower limit threshold can be obtained by formula (5).

[0090] Lower threshold = AIVB…(5)

[0091] For example, when α = "0.5" and the average input video brightness AIVB of the determination target frame = "0.5", the upper threshold can be determined as "0.75" based on formula (4), and the lower threshold can be determined as "0.5" based on formula (5).

[0092] Thereafter, when the average backlight brightness ABB is not included in the range between the upper threshold and the lower threshold of the average input video brightness AIVB of the determination target frame, the processor 400 determines that an abnormality has occurred in the brightness control unit 251 (NG in a black circle). For example, the abnormality of the brightness control unit 251 occurs due to an abnormality in the generation process of the brightness information LINF and the backlight control signal BLCNT. On the other hand, when the average backlight brightness ABB in the average input video brightness AIVB of the determination target frame is included in the range between the upper threshold and the lower threshold, the processor 400 determines that the brightness control unit 251 is in a normal state (OK in a white circle).

[0093] Fig. 9 Is Figure 3 The flowchart is a flowchart of an example of a process in which the processor 400 determines an abnormality of the brightness control unit 251. That is, Fig. 9 An example of an image display control method executed by the processor 400 and an example of an image display control program executed by the processor 400 are shown. Fig. 9 The illustrated flow starts to be executed, for example, when the image display system 1 is activated or when the display controller 40 is activated. It should be noted that the processing from step S10 to step S70 is executed for each frame.

[0094] First, in step S10, the processor 400 causes the image input unit 210 to acquire frame image data. Next, in step S20, the processor 400 causes the input color statistics acquisition unit 240 to acquire the average input video brightness AIVB of the input image data VIN.

[0095] Then, in step S30, the processor 400 obtains the upper and lower thresholds of the average backlight brightness ABB according to the average input video brightness AIVB obtained in step S20. In addition, after step S10, in step S40, the processor 400 causes the output brightness statistics acquisition unit 260 to acquire the average backlight brightness ABB.

[0096] After steps S30 and S40, in step S60, the processor 400 determines whether the average backlight brightness ABB obtained in step S40 is included in the range of the upper threshold and the lower threshold obtained in step S30. When the average backlight brightness ABB is included in the range of the upper threshold and the lower threshold, the processor 400 determines that the brightness control unit 251 is in a normal state and returns the process to step S10. When the average backlight brightness ABB is not included in the range of the upper threshold and the lower threshold, the processor 400 determines that an abnormality has occurred in the brightness control unit 251 and enters the process into step S70.

[0097] In step S70, the processor 400 determines whether the content of the image displayed on the display 50 has been switched. In the case where the content has been switched, the processor 400 determines that the switching of the content has caused the deviation of one or both of the average input video brightness AIVB and the average backlight brightness ABB to increase, and the brightness control unit 251 is determined to be abnormal.

[0098] After that, the processor 400 returns the process to step S10. That is, when the content of the image is switched, even if the average backlight brightness ABB is not included in the range of the upper threshold and the lower threshold, the processor 400 suppresses the abnormality detection process of the brightness control unit 251. When the content is not switched, the processor 400 determines that the brightness control unit 251 is abnormal and enters the process into step S80.

[0099] In step S80, the processor 400 executes processing when an abnormality in the brightness control unit 251 is detected, and ends the process. Fig. 9 An example of step S80 is shown in Fig.10 .

[0100] It should be noted that, when it is determined in step S70 that the content has been switched, the processor 400 may not perform the abnormality determination in step S60 for at least one frame, deeming the brightness control unit 251 to be in a normal state, and returning the process to step S10.

[0101] In addition, the processor 400 may suppress the abnormality detection process of the brightness control unit 251 in step S60 during at least one frame when the image display system 1 or the display controller 40 is started. After that, the processor 400 may not perform the determination of step S60, deeming that the brightness control unit 251 is in a normal state, and return the process to step S10. In this way, it is possible to suppress the false detection of abnormality of the brightness control unit 251 caused by video disturbances when the content is switched or when the device is started.

[0102] Fig.10Yes means Fig. 9 The flowchart of an example of the processing of step S80 of FIG. 4 is shown. First, in step S81, the processor 400 stops the pixel value correction operation of the pixel compensation unit 252. Thereafter, the processor 400 bypasses the pixel compensation unit 252 to output the input image data VIN as the output image data VOUT to the display 50. Accordingly, when the luminance information LINF becomes abnormal due to an abnormality in the luminance control unit 251 and the luminance distribution calculation unit 253 cannot generate a normal luminance distribution, it is possible to suppress the RGB correction unit 254 from using an erroneous luminance distribution to generate the image data VC.

[0103] Next, in step S82, the processor 400 stops the dimming of the local dimming unit 250, turns on all LED light sources of the backlight 60, and sets the backlight 60 to a preset brightness (e.g., the highest brightness). That is, the processor 400 turns on all LED light sources at a predetermined brightness regardless of the operation of the brightness control unit 251. Accordingly, even if the abnormality of the brightness control unit 251 is a reduction in brightness, the image can be displayed on the display 50 without reducing the brightness.

[0104] Then, in step S83, the processor 400 determines whether to allow the display of the icon for indicating the abnormality of the brightness control unit 251. If the display of the icon for indicating the abnormality is allowed, the processor 400 advances the process to step S84. If the display of the icon for indicating the abnormality is not allowed, the processor 400 ends the process. Fig.10 Processing shown.

[0105] In step S84, the processor 400 displays an icon indicating an abnormality on the display 50, and ends the process. Fig.10 In step S84, the processor 400 may also directly control the display 50 and use the OSD (On Screen Display) function of the display 50 to display an icon for indicating an abnormality. In addition, the processor 400 may also input image data for indicating an icon into the image input unit 210 or use the icon data to overwrite the area in the memory 220 that holds the image data, thereby displaying the icon for indicating an abnormality on the display 50.

[0106] As described above, in this embodiment, an abnormality of the brightness control section 251 that could not be detected conventionally can be detected based on the input image data VIN input to the pixel compensation section 252 and the brightness information LINF output from the brightness control section 251 .

[0107] The processor 400 obtains the upper and lower thresholds of the average backlight brightness ABB for determining the abnormality of the brightness control unit 251 based on the average input video brightness AIVB of the input image data VIN input to the local dimming unit 250. Accordingly, the upper and lower thresholds for detecting the abnormality of the brightness control unit 251 can be appropriately set according to the characteristics of the image represented by the input image data VIN of each frame. Therefore, the accuracy of abnormality determination of the brightness control unit 251 can be improved.

[0108] When the content is switched or the display controller 40 is activated, the processor 400 does not perform abnormality detection on the brightness control unit 251 for at least one frame. This can suppress false detection of abnormality of the brightness control unit 251 due to video disturbances when the content is switched or activated.

[0109] When the abnormality of the luminance control unit 251 is detected, the processor 400 stops the pixel value correction operation of the pixel compensation unit 252. Accordingly, when the luminance information LINF becomes abnormal due to the abnormality of the luminance control unit 251 and the luminance distribution calculation unit 253 cannot generate a normal luminance distribution, the RGB correction unit 254 can be prevented from generating the image data VC using an incorrect luminance distribution.

[0110] When an abnormality of the brightness control unit 251 is detected, by lighting all the LED light sources of the backlight 60, even if the abnormality of the brightness control unit 251 is a reduction in brightness, the image can be displayed on the display 50 without reducing the brightness. In addition, when an abnormality of the brightness control unit 251 is detected, the abnormality of the brightness control unit 251 can be notified to the user, etc. by displaying an icon for indicating the abnormality on the display 50. It should be noted that, in fact, the icon for indicating the abnormality is one or both of a graphic and text that can recognize the abnormality of the display controller 40 by the user, etc.

[0111] In addition, even if the brightness control unit 251 is abnormal and the normal local dimming process is not performed, and the contrast of the image displayed on the display device 70 is low, the abnormality of the brightness control unit 251 can be detected and all the LED light sources of the backlight 60 can be turned on. In this way, the contrast of the image displayed on the display device 70 can be improved, thereby meeting the ASIL requirements.

[0112] (Second embodiment)

[0113] Fig.11 FIG. 1 is a block diagram showing an example of a display controller according to the second embodiment. Figure 2 Similar elements are given the same reference numerals, and detailed descriptions thereof are omitted. Fig.11 The display controller 40A shown in the figure is installed in place of the display controller 40, for example. Figure 1An image display system 1.

[0114] Display controller 40A replaces Figure 2 The display engine 200 has a display engine 200A. The display engine 200A has Figure 2 The display engine 200 of the present invention has an additional output color statistics acquisition unit 290 and a Figure 2 The display engine 200 is similarly constructed.

[0115] The output color statistics acquisition unit 290 sequentially acquires the average output video brightness AOVB, which is the average of pixel values ​​of one screen (one frame) included in the output image data VOUT output from the local dimming unit 250 to the image output unit 270. For example, the output color statistics acquisition unit 290 acquires the average output video brightness AOVB by calculation.

[0116] In this embodiment, the average input video brightness AIVB is an example of the first statistical data. The input color statistics acquisition unit 240 is an example of the first statistical data acquisition unit. The average output video brightness AOVB is an example of the second statistical data. The output color statistics acquisition unit 290 is an example of the second statistical data acquisition unit. The average backlight brightness ABB is an example of the third statistical data. The output brightness statistics acquisition unit 260 is an example of the third statistical data acquisition unit.

[0117] The output color statistics acquisition unit 290 outputs the acquired average output video brightness AOVB to the processor 400 via the register interface 280 and the bus 500. It should be noted that the output color statistics acquisition unit 290 may have a storage unit such as a buffer for holding the average output video brightness AOVB. In this case, the average output video brightness AOVB held in the storage unit can be read by the processor 400.

[0118] Fig.12 It means Fig.11 1 is a block diagram of an example of an input color statistics acquisition unit 240, an output luminance statistics acquisition unit 260, and an output color statistics acquisition unit 290 connected to the local dimming unit 250. Fig.12 In, yes Figure 2 The description of the register interface 280 and the bus 500 is omitted. In addition, except for the addition of the output color statistics acquisition unit 290, the configuration and connection relationship of the local dimming unit 250, the input color statistics acquisition unit 240 and the output brightness statistics acquisition unit 260 are the same as those of the previous embodiment. Figure 3 similar.

[0119] It should be noted that the input color statistics acquisition unit 240 acquires the statistical data of the input image data VIN normalized to be greater than 0 and less than 1, namely, the average input video brightness AIVB. The output color statistics acquisition unit 290 acquires the statistical data of the output image data VOUT normalized to be greater than 0 and less than 1, namely, the average output video brightness AOVB. Accordingly, the processor 400 can calculate the upper and lower thresholds described later without matching the scales (number of bits, etc.) of the average input video brightness AIVB and the average output video brightness AOVB.

[0120] Fig.13 It means by Fig.12 The statistical data (average input video brightness AIVB and average backlight brightness ABB) acquired by the input color statistics acquisition unit 240 and the output brightness statistics acquisition unit 260 are compared with the statistical data (average input video brightness AIVB and average backlight brightness ABB) acquired by the input color statistics acquisition unit 240 and the output brightness statistics acquisition unit 260. Figure 7 similar.

[0121] The output color statistics acquisition unit 290 obtains the maximum value MAX of the pixel value (the maximum value of the pixel value of the red pixel, the pixel value of the green pixel, and the pixel value of the blue pixel) for each pixel in all pixels of the output image data VOUT of each frame. Then, the output color statistics acquisition unit 290 obtains the average output video brightness AOVB by dividing the sum of the maximum values ​​MAX of all pixels by the number of all pixels.

[0122] Fig.14 It is used to determine Fig.12 FIG. 4 is a diagram showing an example of an abnormal threshold value of the brightness control unit 251. The processor 400 determines whether the brightness of the backlight 60 is abnormal according to the input image data VIN for each frame.

[0123] like Figure 6 As described above, in the image brightness correction performed by the RGB correction unit 254, the input image data VIN is divided by the brightness (brightness distribution) of the backlight 60, and accordingly, as shown in formula (6), the brightness of the backlight 60 can be offset. By moving the "backlight brightness" on the left side of formula (6) to the right side, formula (7) can be obtained.

[0124] Input image data VIN / backlight brightness = output image data VOUT…(6)

[0125] Input image data VIN = backlight brightness × output image data VOUT (7)

[0126] For example, in formula (7), "input image data VIN" can be approximated to the "average input video brightness AIVB" obtained by the input color statistics acquisition unit 240. "Output image data VOUT" can be approximated to the "average output video brightness AOVB" obtained by the output color statistics acquisition unit 290. "Backlight brightness" can be approximated to the "average backlight brightness ABB" obtained by the output brightness statistics acquisition unit 260. Then, by substituting each approximation term into formula (7), formula (8) can be obtained. That is, "average backlight brightness ABB×average output video brightness AOVB" has a value equivalent to (approximate to) the "average input video brightness AIVB".

[0127] Average input video brightness AIVB≈average backlight brightness ABB×average output video brightness AOVB…(8)

[0128] In this embodiment, with respect to the "average input video brightness AIVB" acquired by the input color statistics acquisition unit 240, if the "average backlight brightness ABB×average output video brightness AOVB" does not fall within the predetermined range, the processor 400 determines that an abnormality has occurred in the brightness control unit 251. The predetermined range is represented by an upper threshold and a lower threshold. "Average backlight brightness ABB×average output video brightness AOVB" is an example of output statistical data. The upper threshold is an example of an upper limit value, and the lower threshold is an example of a lower limit value.

[0129] Here, if Figure 5 As described above, the luminance distribution of the backlight 60 is obtained by taking into account the color bleeding of light to the adjacent LED regions. Since the amount of color bleeding from the adjacent LED regions is increased, the actual luminance of each LED region of the backlight 60 is higher than the set luminance set for each LED light source. That is, since the amount of color bleeding from the adjacent LED regions is not taken into account, the "average backlight luminance ABB" is less than the actual luminance average value of the LED regions of the backlight 60.

[0130] Therefore, the "average backlight brightness ABB×average output video brightness AOVB" of formula (8) will not exceed the product of the actual brightness of the backlight 60 and the output image data VOUT output from the pixel compensation unit 252. In formula (8), the upper limit threshold of the "average backlight brightness ABB×average output video brightness AOVB" will not exceed the average input video brightness AIVB. Therefore, the "average input video brightness AIVB" itself is set as the upper limit threshold (formula (9)).

[0131] Upper threshold = average input video brightness AIVB…(9)

[0132] Since the "average backlight brightness ABB" is less than the actual brightness average of the LED area of ​​the backlight 60, the lower limit threshold of "average backlight brightness ABB × average output video brightness AOVB" needs to be set by considering the amount of color bleeding from the adjacent LED area. For this purpose, the lower limit threshold is set to the value obtained by multiplying the "average input video brightness AIVB" by the brightness adjustment parameter β (0<β<1) (Formula (10)). The brightness adjustment parameter β is an example of a coefficient multiplied by the average input video brightness AIVB. For example, the brightness adjustment parameter β is set to Fig.14 The ratio of area A to area B is A / B. Area A is the integrated value of the brightness when one LED light source is turned on without considering the light bleeding. Area B is the integrated value of the brightness when the light bleeding is considered. Figure 5 The integrated value of the luminance of the luminance distribution shown.

[0133] Lower threshold = average input video brightness AIVB × β…(10)

[0134] The "average input video brightness AIVB" of formula (9) and the "average input video brightness AIVB×β" of formula (10) are examples of input statistical data. Afterwards, when the "average backlight brightness ABB×average output video brightness AOVB" of the judgment object frame is not included in the range between the upper threshold and the lower threshold shown in formula (9) and formula (10), the processor 400 determines that an abnormality has occurred in the brightness control unit 251 (NG with a black circle). When the "average backlight brightness ABB×average output video brightness AOVB" of the judgment object frame is included in the range between the upper threshold and the lower threshold shown in formula (9) and formula (10), the processor 400 determines that the brightness control unit 251 is in a normal state (OK with a white circle).

[0135] Fig.15 It means by Fig.12 The flowchart is a flowchart of an example of a process in which the processor 400 determines an abnormality of the brightness control unit 251. That is, Fig.15 4 is a schematic diagram of an example of an image display control method executed by the processor 400 and an image display control program executed by the processor 400. Fig. 9 Similar processing is omitted in its detailed description. Fig.15 The illustrated flow starts to be executed, for example, when the image display system 1 is activated or when the display controller 40 is activated. It should be noted that the processing from step S10 to step S70 is executed for each frame.

[0136] Fig.15 In the process shown, replace Fig. 9 Steps S30 and S60 are respectively performed, and steps S30A and S60A are respectively performed. In addition, step S50 is added between step S30A and step S60A. Fig.15 Other processing and Fig. 9 The processing of step S80 is similar to Fig.10 The processing shown is the same.

[0137] In step S30A, the processor 400 calculates the upper threshold and the lower threshold corresponding to the product of the average backlight brightness ABB and the average output video brightness AOVB according to the average input video brightness AIVB obtained in step S20 and the brightness adjustment parameter β obtained in advance. Then, in step S50, the processor 400 enables the output color statistics acquisition unit 290 to acquire the average output video brightness AOVB of the output image data VOUT. It should be noted that step S50 can be executed in parallel with steps S20 and S40.

[0138] After steps S40 and S50, in step S60A, the processor 400 obtains the product "ABB×AOVB" of the average backlight brightness ABB and the average output video brightness AOVB obtained in steps S40 and S50. Thereafter, the processor 400 determines whether the obtained product "ABB×AOVB" is included in the range of the upper threshold and the lower threshold obtained in step S30A.

[0139] If the product "ABB×AOVB" is within the range of the upper threshold and the lower threshold, the processor 400 determines that the brightness control unit 251 is in a normal state and returns the process to step S10. If the product "ABB×AOVB" is not within the range of the upper threshold and the lower threshold, the processor 400 determines that an abnormality has occurred in the brightness control unit 251 and returns the process to step S70. The processes of steps S70 and S80 are similar to those of steps S11 and S12. Fig. 9 The processing of steps S70 and S80 is the same.

[0140] As described above, even in this embodiment, effects similar to those of the above-described embodiment can be obtained. For example, based on the input image data VIN input to the pixel compensation unit 252, the output image data VOUT output from the pixel compensation unit 252, and the brightness information LINF output from the brightness control unit 251, an abnormality of the brightness control unit 251 that could not be detected in the past can be detected.

[0141] In addition, in the present embodiment, the processor 400 can also obtain the upper threshold and the lower threshold without using the brightness adjustment parameter α. Accordingly, the upper threshold or the lower threshold can be suppressed from changing depending on the brightness adjustment parameter α set by the user or the like. Therefore, for example, the normal range of the brightness of the backlight 60 set by the upper threshold and the lower threshold can be suppressed from becoming larger depending on the brightness adjustment parameter α, and the decrease in the abnormality detection accuracy of the brightness control unit 251 can be suppressed.

[0142] It should be noted that in the first and second embodiments, the pixel value of the input image data VIN input to the local dimming unit 250 is Fig. 9 Step S30 or Fig.15 The example of obtaining the upper and lower thresholds in step S30A is described. However, when the image displayed on the display device 70 is determined, the upper and lower thresholds can also be obtained based on the pixel values ​​corresponding to the displayed image acquired in advance. In this case, the upper and lower thresholds corresponding to the displayed image are stored in the memory 300 and can be referenced (read) by the processor 400. In this case, the upper and lower thresholds can be omitted. Fig. 9 Step S30 and Fig.15 The process of calculating the upper threshold value and the lower threshold value in step S30A.

[0143] In addition, in the first and second embodiments described above, an example is described in which an upper threshold value and a lower threshold value are calculated based on all pixel values ​​of the input image data VIN input to the local dimming unit 250, and an abnormality of the brightness control unit 251 is detected based on the calculated upper threshold value and lower threshold value. However, the upper threshold value and the lower threshold value may be calculated based on pixel values ​​of a smaller number of pixels in the image obtained by thinning a part of the pixels included in the input image data VIN, not based on all pixel values ​​included in the input image data VIN. In this case, the calculation load of the input color statistics acquisition unit 240 and the output color statistics acquisition unit 290 can be reduced, and the calculation load of the processor 400 for the upper threshold value and the lower threshold value can be reduced. Therefore, the increase in power consumption of the display controllers 40 and 40A can be suppressed.

[0144] Although the present invention has been described above based on the various embodiments, the present invention is not limited to the requirements shown in the above embodiments. These can be changed within the scope of the gist of the present invention and can be appropriately determined based on the application form.

[0145] [Explanation of Reference Numerals]

[0146] 1 Image display system

[0147] 10 head unit

[0148] 20Serializer

[0149] 30 deserializer 40, 40A display controller

[0150] 50 Display

[0151] 60 backlight 200, 200A display engine

[0152] 210 Image input unit

[0153] 220 Memory

[0154] 230 Deformation Department

[0155] 240 Input color statistics acquisition unit 250 Local dimming unit

[0156] 251 Brightness Control Unit

[0157] 252 pixel compensation unit

[0158] 253 Luminance distribution calculation unit

[0159] 254RGB correction unit

[0160] 255 Saturation Processing Unit

[0161] 260 Output brightness statistics acquisition unit 270 Image output unit

[0162] 280 register interface

[0163] 290 Output color statistics acquisition unit 300 Memory

[0164] 400 processors

[0165] 500 bus ABB average backlight brightness AIVB average input video brightness AOVB average output video brightness

[0166] BLCNT backlight control signal

[0167] LINF brightness information

[0168] LSF brightness distribution function

[0169] VC image data

[0170] VIN input image data

[0171] VOUT outputs image data.

Claims

1. An image display control device with a local dimming function, comprising: a brightness control unit that generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image; a pixel compensation unit that corrects the pixel values ​​included in the first image information according to the brightness of the plurality of light sources to generate second image information representing an output image; a first statistics acquisition unit, which acquires first statistical data of pixel values ​​included in the first image information; a second statistics acquisition unit, which acquires second statistical data of the brightness value of each light source included in the backlight control information; and The abnormality detection unit detects abnormality of the brightness control unit based on whether the second statistical data is included in a range between an upper limit value and a lower limit value determined by the first statistical data.

2. The image display control device according to claim 1, wherein: The first statistical data is an average value of the brightness of the input image obtained based on the pixel values ​​of the first image information. The second statistical data is an average value of the luminance values ​​of the light sources included in the backlight control information.

3. An image display control device with a local dimming function, comprising: a brightness control unit that generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image; a pixel compensation unit that corrects the pixel values ​​included in the first image information according to the brightness of the plurality of light sources to generate second image information representing an output image; a first statistics acquisition unit, which acquires first statistical data of pixel values ​​included in the first image information; a second statistics acquisition unit, which acquires second statistical data of pixel values ​​included in the second image information; a third statistical acquisition unit, which acquires third statistical data of the brightness value of each light source included in the backlight control information; and The abnormality detection unit detects abnormality of the brightness control unit based on whether the output statistical data obtained based on the second statistical data and the third statistical data are included in a range between an upper limit value and a lower limit value determined by the input statistical data obtained based on the first statistical data.

4. The image display control device according to claim 3, wherein: The first statistical data is an average value of the brightness of the input image obtained based on the pixel values ​​of the first image information. The input statistical data is the first statistical data or a value obtained by multiplying the first statistical data by a coefficient, The second statistical data is an average value of the brightness of the output image obtained based on the pixel values ​​of the second image information. The third statistical data is an average value of the luminance values ​​of each light source included in the backlight control information. The output statistical data has a value corresponding to an average value of the luminance of the input image obtained by multiplying the second statistical data and the third statistical data.

5. The image display control device according to claim 1, wherein: When the content of the image displayed on the display unit indicated by the second image information is switched or the image display control device is activated, the abnormality detection unit suppresses a process of detecting an abnormality of the brightness control unit during at least one frame.

6. The image display control device according to claim 1, wherein: When an abnormality of the brightness control unit is detected, the abnormality detection unit outputs the first image information as the second image information regardless of an operation of the pixel compensation unit, and turns on the plurality of light sources regardless of the operation of the brightness control unit.

7. The image display control device according to claim 3, wherein: When the content of the image displayed on the display unit indicated by the second image information is switched or the image display control device is activated, the abnormality detection unit suppresses a process of detecting an abnormality of the brightness control unit during at least one frame.

8. The image display control device according to claim 3, wherein: When an abnormality of the brightness control unit is detected, the abnormality detection unit outputs the first image information as the second image information regardless of an operation of the pixel compensation unit, and turns on the plurality of light sources regardless of the operation of the brightness control unit.

9. An image display control device having a display engine that performs local dimming processing and a processor that controls the operation of the display engine, wherein: The display engine inputting first image information for representing an image to be displayed on the display unit, maintaining the first image information, generating backlight control information for controlling a plurality of light sources included in a backlight according to the first image information, The pixel values ​​included in the first image information are corrected according to the brightness of the plurality of light sources to generate second image information representing an output image. obtaining first statistical data of pixel values ​​included in the first image information, acquiring second statistical data of the brightness value of each light source included in the backlight control information, outputting the second image information to the display unit, The processor detects an abnormality in the generation process of the backlight control information based on whether the second statistical data is included in a range between an upper limit value and a lower limit value determined by the first statistical data.

10. An image display control device having a display engine that performs local dimming processing and a processor that controls the operation of the display engine, wherein: The display engine inputting first image information for representing an image to be displayed on the display unit, maintaining the first image information, generating backlight control information for controlling a plurality of light sources included in a backlight according to the first image information, The pixel values ​​included in the first image information are corrected according to the brightness of the plurality of light sources to generate second image information representing an output image. obtaining first statistical data of pixel values ​​included in the first image information, acquiring second statistical data of pixel values ​​included in the second image information, obtaining third statistical data of the brightness value of each light source included in the backlight control information, outputting the second image information to the display unit, The processor detects abnormality in the generation process of the backlight control information according to whether the output statistical data obtained based on the second statistical data and the third statistical data are included in a range between an upper limit value and a lower limit value determined by input statistical data obtained based on the first statistical data.

11. An image display control device with a local dimming function, comprising: a brightness control unit that generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image; a pixel compensation unit that corrects the pixel values ​​included in the first image information according to the brightness of the plurality of light sources to generate second image information representing an output image; A first statistical acquisition unit, which acquires first statistical data of the brightness value of each light source included in the backlight control information; and The abnormality detection unit detects abnormality of the brightness control unit based on whether the first statistical data is included in a range between an upper limit value and a lower limit value determined by the input image or the output image.

12. An image display control device with a local dimming function, comprising: a brightness control unit that generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image; a pixel compensation unit that corrects the pixel values ​​included in the first image information according to the brightness of the plurality of light sources to generate second image information representing an output image; a first statistics acquisition unit, which acquires first statistical data of pixel values ​​included in the second image information; a second statistics acquisition unit, which acquires second statistical data of the brightness value of each light source included in the backlight control information; and The abnormality detection unit detects abnormality of the brightness control unit based on whether output statistical data obtained based on the first statistical data and the second statistical data are included in a range between an upper limit value and a lower limit value determined by the input image or the output image.

13. An image display system comprising: The image display control device according to claim 1; Display unit; The backlight is arranged opposite to the display portion; and The head unit generates an image and outputs the first image information indicating the generated image to the image display control device.

14. An image display system comprising: The image display control device according to claim 3; Display unit; The backlight is arranged opposite to the display portion; and The head unit generates an image and outputs the first image information indicating the generated image to the image display control device.

15. An image display control method performed by an image display control device having a local dimming function, wherein: The brightness control unit of the image display control device generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image. The pixel compensation unit of the image display control device corrects the pixel values ​​included in the first image information according to the luminance of the plurality of light sources to generate second image information representing an output image. The first statistic obtaining unit of the image display control device obtains first statistic data of pixel values ​​included in the first image information. The second statistical data of the luminance value of each light source included in the backlight control information is acquired by a second statistical acquisition unit of the image display control device. The abnormality detection unit included in the image display control device detects abnormality in the brightness control unit based on whether the second statistical data is included in a range between an upper limit value and a lower limit value determined by the first statistical data.

16. An image display control method performed by an image display control device having a local dimming function, wherein: The brightness control unit of the image display control device generates backlight control information for controlling a plurality of light sources included in the backlight based on first image information representing an input image. The pixel compensation unit of the image display control device corrects the pixel values ​​included in the first image information according to the luminance of the plurality of light sources to generate second image information representing an output image. The first statistic obtaining unit of the image display control device obtains first statistic data of pixel values ​​included in the first image information. The second statistic obtaining unit of the image display control device obtains second statistic data of pixel values ​​included in the second image information. The third statistical data of the luminance value of each light source included in the backlight control information is acquired by a third statistical acquisition unit of the image display control device. The abnormality detection unit possessed by the image display control device detects abnormality of the brightness control unit based on whether the output statistical data obtained based on the second statistical data and the third statistical data are included in the range between the upper limit value and the lower limit value determined by the input statistical data obtained based on the first statistical data.

Images