Image processing device, image processing method, and computer program

Abstract

The purpose of the present invention is to provide an image processing device, an image processing method, and a computer program that suppress flicker and prevent degradation of image quality due to flicker suppression processing. An image processing apparatus that performs correction processing for correcting a second frame on the basis of a first frame and the second frame includes a flicker component estimation unit configured to obtain a flicker component value on the basis of pixel values of pixels in regions of the first frame and the second frame, and a pixel value correction unit configured to correct the flicker component value on the basis of the pixel values of the pixels in the regions of the first frame and the second frame. The in-region pixels are composed of a plurality of pixels included in a predetermined region of a first frame and a second frame, the plurality of pixels including a pixel of interest and surrounding pixels provided around the pixel of interest; the flicker component value corresponds to a degree of flicker occurring in the image display unit due to a pixel response delay of pixels in the region when the first frame transitions to the second frame. The pixel response delay corresponds to a difference in response speed between an increasing pixel in which the pixel value increases and a decreasing pixel in which the pixel value decreases among the plurality of pixels when transitioning from a first frame to a second frame; the pixel value correction unit is configured to acquire a corrected pixel value, which is a value obtained by correcting the pixel value of the pixel of interest in the second frame, on the basis of the flicker component value.

Description

Technical Field

[0001] The present invention relates to an image processing device, an image processing method and a computer program. Background Art

[0002] When the frame displayed on the image display unit transitions, the pixel value (brightness) of each pixel changes based on the displayed frame. Among them, since the response speed of the pixel value of the pixel whose pixel value increases is different from the response speed of the pixel value of the pixel whose pixel value decreases, flickering may occur in the image display unit when the frame transitions. In other words, since there is a pixel response delay between the pixel whose pixel value increases and the pixel whose pixel value decreases, flickering may occur in the image display unit, resulting in reduced image quality. Therefore, patent document 1 discloses a technology for suppressing flickering by reducing the response speed of the pixel whose pixel value decreases. Prior art documents (Patent Document)

[0003] Patent Document 1: U.S. Patent Application Publication No. 2011 / 0199287 Summary of the invention (Problems to be solved by the invention)

[0004] When the frame displayed on the image display unit is, for example, a frame called a dot grid in which white pixels and black pixels are alternately arranged, flickering often occurs. On the other hand, the image display unit may also display frames that are less prone to flickering. As an example, the transition from a pure white frame (e.g., the maximum pixel value of all pixels) to a pure black frame (e.g., the minimum pixel value) can be cited. In this case, the pixel values ​​of all pixels of the image display unit decrease during the frame transition. In this case, if the technology of patent document 1 is uniformly applied to the frames, the response speed of all pixels of the image display unit will decrease, which may in turn reduce the image quality.

[0005] The present invention has been invented in view of such circumstances, and aims to provide an image processing device, an image processing method, and a computer program that suppress flicker and prevent degradation of image quality due to flicker suppression processing. (Technical solutions to problems)

[0006] According to the present invention, there is provided an image processing device for performing correction processing of correcting a second frame based on a first frame and a second frame, the device comprising a flicker component estimation unit and a pixel value correction unit, wherein the flicker component estimation unit is configured to obtain a flicker component value based on pixel values ​​of pixels within an area of ​​the first frame and the second frame, the pixels within the area being composed of a plurality of pixels included in a predetermined area of ​​the first frame and the second frame, the plurality of pixels having a focus pixel and surrounding pixels arranged around the focus pixel, the flicker component value corresponding to a degree of flicker occurring in an image display unit due to a pixel response delay of pixels within the area when transitioning from the first frame to the second frame, the pixel response delay corresponding to a difference in response speed between increasing pixels whose pixel values ​​increase and decreasing pixels whose pixel values ​​decrease in the plurality of images when transitioning from the first frame to the second frame, the pixel value correction unit being configured to obtain a corrected pixel value based on the flicker component value, the corrected pixel value being a value obtained by correcting the pixel value of the focus pixel of the second frame.

[0007] In the present invention, the pixel value correction unit is configured to obtain a corrected pixel value based on a flicker component value. The flicker component value is based not only on the pixel value of the focus pixel in the first frame and the second frame, but also on the pixel values ​​of the surrounding pixels arranged around the focus pixel. Since the value of the content (type) of the first frame and the second frame is taken into consideration, the corresponding correction pixel value is also taken into consideration. The value of the content of the first frame and the second frame. Therefore, when flicker is suppressed, the degradation of image quality can be prevented according to the content of the first frame and the second frame.

[0008] Various embodiments of the present invention are described below. The embodiments described below can be combined with each other. (1) An image processing device that performs correction processing for correcting the second frame based on a first frame and a second frame, and includes a flicker component estimation unit and a pixel value correction unit, wherein the flicker component estimation unit is configured to obtain a flicker component value based on pixel values ​​of pixels within an area of ​​the first frame and the second frame, wherein the pixels within the area are composed of a plurality of pixels included in a predetermined area of ​​the first frame and the second frame, wherein the plurality of pixels have a focus pixel and surrounding pixels arranged around the focus pixel, wherein the flicker component value corresponds to a degree of flicker that occurs in an image display unit due to a pixel response delay of the pixels within the area when transitioning from the first frame to the second frame, wherein the pixel response delay corresponds to a difference in response speed between an increasing pixel whose pixel value increases and a decreasing pixel whose pixel value decreases among the plurality of pixels when transitioning from the first frame to the second frame, and wherein the pixel value correction unit is configured to obtain a corrected pixel value based on the flicker component value, wherein the corrected pixel value is a value obtained by correcting the pixel value of the focus pixel of the second frame. (2) An image processing device according to (1), wherein the flicker component estimation unit obtains the flicker component value based on a difference between a first statistical value and a second statistical value, wherein the first statistical value is a statistical value of the pixel values ​​of the multiple pixels within the area of ​​the first frame, and the second statistical value is a statistical value of the pixel values ​​of the multiple pixels within the area of ​​the second frame. (3) An image processing device according to (2), wherein the statistical value is an average value, a dispersion value, a median value or a low-frequency component value of the pixel values ​​of the multiple pixels in the pixel area, and the low-frequency component value is a weighted value in a probability density distribution based on at least one of the distance between pixels and the pixel value. (4) An image processing device according to any one of (1) to (3), wherein the flicker component estimation unit obtains the flicker component value based on an increase value and a decrease value, the increase value is based on the pixel value of the increased pixel among the multiple pixels when transitioning from the first frame to the second frame, and the decrease value is based on the pixel value of the decreased pixel among the multiple pixels when transitioning from the first frame to the second frame. (5) An image processing device according to (4), wherein the increase value is the sum of the difference values ​​of the pixel values ​​of the first frame and the second frame in the increase pixel, and the decrease value is the sum of the difference values ​​of the pixel values ​​of the first frame and the second frame in the decrease pixel. (6) The image processing device according to any one of (1) to (5) further includes a pixel value determination unit, the pixel value correction unit is configured to obtain a transformation amount based on the flicker component value, and obtain the corrected pixel value based on the transformation amount, and the pixel value determination unit determines the pixel value of the focus pixel of the first frame used in the correction processing after the current correction processing based on the size of the transformation amount. (7) In the image processing device according to (6), when the transition amount is greater than a predetermined threshold value, the pixel value determination unit uses the pixel value of the focus pixel of the first frame used in the correction processing after the current correction processing as the pixel value of the focus pixel of the second frame of the current correction processing; when the transition amount is less than the predetermined threshold value, the pixel value determination unit uses the pixel value of the focus pixel of the first frame used in the correction processing after the current correction processing as the transition pixel value, and the transition pixel value is the correction pixel value obtained in the current correction processing, the pixel value of the focus pixel of the second frame of the current correction processing, or a value between the two. (8) The image processing device according to any one of (1) to (7), further comprising the image display unit configured to display a frame reflecting the corrected pixel value acquired by the pixel value correction unit. (9) An image processing method, which performs correction processing for correcting the second frame based on the first frame and a second frame that is a frame subsequent to the first frame, The image processing method comprises a flicker component estimation step and a pixel value correction step. In the flicker component estimation step, a flicker component value is obtained based on the pixel values ​​of pixels in the area of ​​the first frame and the second frame. The pixels in the area are composed of a plurality of pixels included in a predetermined area of ​​the first frame and the second frame. The plurality of pixels have a focus pixel and surrounding pixels arranged around the focus pixel. The flicker component value corresponds to the degree of flicker occurring in the image display unit due to a pixel response delay within the pixels in the area when transitioning from the first frame to the second frame. The pixel response delay corresponds to the difference in response speed between an increasing pixel whose pixel value increases and a decreasing pixel whose pixel value decreases among the plurality of pixels when transitioning from the first frame to the second frame. In the pixel value correction step, a corrected pixel value is obtained based on the flicker component value. The corrected pixel value is a value obtained by correcting the pixel value of the focus pixel of the second frame. (10) A program causing a computer to execute the image processing method according to (9). BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 1 is a schematic diagram showing an image processing device 100 according to an embodiment and an output device 200 that outputs a video signal. Figure 2 middle, Figure 2 A is Figure 1 The functional block diagram of the image processing device 100 shown in FIG. 1 shows a data flow related to a pair of frames F1 and F2 (an example of the first and second frames). Figure 2 B is Figure 1 The functional block diagram of the image processing device 100 shown in FIG. 1 shows a data flow related to a pair of frames F2 and F3 (an example of the first and second frames). Figure 2 p2(x, y) and p3(x, y) in A and 2B correspond to the corrected pixel values ​​p(x, y) calculated sequentially using a pair of frames, and the "2" in "p2" or the "3" in "p3" indicates the order of the frames. Similarly, Figure 2 d2(x, y) and d3(x, y) in A and 2B correspond to pixel values ​​d(x, y) determined sequentially by the image processing unit 10 and stored in the frame memory 30 using a pair of frames, and the "2" in "d2" or the "3" in "d3" indicates the order of the frames. Figure 3 yes Figure 1 The functional block diagram of the image processing apparatus 100 shown in FIG. Figure 2 A shows the detailed structure of the image processing unit 10. Figure 4 middle, Figure 4 A and 4B show an example of a frame where flickering is likely to occur (a frame of a dot grid). Figure 4 A represents the pixel Rg in the frame, the focus pixel a1 and the surrounding pixels a2. Figure 4 B means Figure 4 A is a pixel Rg in the region of a different target pixel a1. Figure 5 This is a graph for explaining situations where flicker is likely to occur. Figure 6 middle, Figure 6 A and 6B are the added values ​​(R SUM ) and the reduction value (F SUM ) is an illustration of an example of a method, Figure 6 A represents the pixel value of the pixel Rg in the region of the Nth frame (corresponding to frame F1), Figure 6 B represents the pixel value of pixel Rg in the area of ​​frame N+1 (corresponding to frame F2). Figure 6 In A and 6B, the pixel values ​​(numbers) of the added pixels are highlighted by underlining. Figure 7 Is when Figure 6 B is an explanatory diagram of the pixel value (corrected pixel value) of the pixel a1 of interest when the correction process is performed on the pixel a1 of interest in the frame F2 of the pixel Rg in the region. Figure 8 This is Modification 5 of the image processing device 100 according to the embodiment. DETAILED DESCRIPTION

[0010] The following is an illustration of the embodiment of the present invention. The various features shown in the following embodiment can be combined with each other. In addition, each feature independently constitutes the present invention.

[0011] 1. Overall composition description The overall structure of the image processing device 100 according to the embodiment will be described. Figure 1 As shown, the image processing apparatus 100 is communicably connected to the output apparatus 200. The output apparatus 200 is an information processing apparatus (for example, a personal computer) and is configured to output a video signal.

[0012] like Figure 2As shown in FIG. 2A and FIG. 2B , the image processing device 100 includes an image processing unit 10, an image display unit 20, and a frame memory 30. The image display unit 20 may be formed of, for example, a liquid crystal monitor, and the frame memory 30 stores the pixel value of each pixel of the frame used in various processes of the image processing unit 10. Figure 3 As shown, the image processing apparatus 100 includes a flicker component estimation unit 1 , a pixel value correction unit 2 , and a pixel value determination unit 3 . Each component of the image processing device 100 can be implemented by software or hardware. When implemented by software, various functions can be implemented by executing a computer program by the CPU. The program can be stored in a built-in memory or in a non-temporary recording medium readable by a computer. Alternatively, the program stored in an external memory can be read out and implemented through so-called cloud computing. When implemented by hardware, it can be implemented by various circuits such as ASIC, FPGA or DRP (Dynamically Reconfigurable Processor). In this embodiment, various information or concepts including these are processed, which are represented by the high and low signal values ​​as a set of binary bits composed of 0 or 1, and can be communicated or calculated by the above-mentioned software or hardware.

[0013] The image processing device 100 has a function of suppressing flicker, which is a flicker that occurs on the image display unit 20 due to pixel response delay during frame transition. It should be noted that the frame transition corresponds to the transition from a frame at any moment to a frame at the next moment.

[0014] In addition, the pixel response delay means that there is a response difference between pixels based on the operation details of the pixels of the image display unit 20. Specifically, the image display unit 20 is composed of a liquid crystal monitor, and the response speed of each pixel of the image display unit 20 when the pixel value increases is slower than the response speed when the pixel value of each pixel of the image display unit 20 decreases. In other words, when the frame transitions, the pixel whose pixel value decreases (decreasing pixel) reaches the desired pixel value faster than the pixel whose pixel value increases (increasing pixel).

[0015] In addition, in the present embodiment, an increase in pixel value means that the pixel value (relatively low value) of a pixel at any coordinate in frame F1 increases to the pixel value (relatively high value) of a pixel at the same coordinate in frame F2. Similarly, a decrease in pixel value means that the pixel value (relatively high value) of a pixel at any coordinate in frame F1 decreases to the pixel value (relatively low value) of a pixel at the same coordinate in frame F2. Next, an overview of data including frame F1 or frame F2 described here or its data stream will be described.

[0016] exist Figure 2In A, the image processing unit 10 obtains the video signal of frame F2 and simultaneously obtains the pixel value d1(x, y) corresponding to frame F1, which is the frame before frame F2. The pixel value d1(x, y) is Figure 2 The pixel value determined by the pixel value determination unit 3 described later before the processing of A corresponds to the pixel value d1 (x, y) of the frame F1 and is stored in the frame memory 30. Figure 2 As shown in A, the corrected pixel value p2(x, y) corresponding to the frame F2 is input to the image display unit 20. The corrected pixel value p2(x, y) is a pixel value calculated by the pixel value correction unit 2 described later. After the corrected pixel value p1(x, y) corresponding to the frame F1 is input to the image display unit 20 (p1 is not shown), the pixel value d1(x, y) corresponding to the frame F1 is a value that takes into account the conversion amount of the pixel value actually displayed on the image display unit 20. And the pixel value d1(x, y) corresponding to the frame F1 may be the same as or different from the pixel value actually displayed by the image display unit 20. The value of the pixel value d1(x, y) is determined by the pixel value determination unit 3 described later.

[0017] In addition, the frame having the pixel value d1 (x, y) corresponding to the frame F1 is an example of the first frame. The image processing unit 10 processes the frame F2 which is a frame after the frame F1 and is the correction object. The frame F2 is an example of the second frame. If the second frame is not corrected, flickering may occur in some cases when transitioning from the first frame to the second frame.

[0018] In the processing of the next frame, if Figure 2 As shown in FIG. 2B , the image processing unit 10 simultaneously obtains the pixel value d2(x, y) when obtaining the video signal of frame F3. The pixel value d2(x, y) corresponds to the frame before frame F3, i.e., frame F2. The pixel value d2(x, y) is Figure 2 The pixel value determined by the pixel value determination unit 3 in the process of A corresponds to the pixel value d2 (x, y) of the frame F2 and is stored in the frame memory 30. Figure 2 As shown in FIG. 2B, the corrected pixel value p3(x, y) corresponding to the frame F3 is input to the image display unit 20. Like the corrected pixel value p2(x, y), the corrected pixel value p3(x, y) is also a pixel value calculated by the pixel value correction unit 2 described later.

[0019] The frame having the pixel value d2 (x, y) corresponding to the frame F2 is an example of the first frame. The frame F3 which is a frame subsequent to the frame F2 and is a correction target is an example of the second frame.

[0020] 2 Image processing unit 10 like Figure 2As shown in A, the image processing unit 10 is configured to perform correction processing for correcting the frame F2 based on the video signal of the frame F1 and the video signal of the frame F2 that follows the frame F1. Figure 3 As shown, the image processing unit 10 includes a flicker component estimation unit 1 for executing various processes including the correction process, a pixel value correction unit 2, and a pixel value determination unit 3. The flicker component estimation unit 1 and the like will be described below.

[0021] 2-1 Flicker component estimation unit 1 The flicker component estimation unit 1 is configured to obtain a flicker component value F based on the pixel value of the pixel Rg in the region of the frame F1 and the pixel value of the pixel Rg in the region of the frame F2. DEGREE The flicker component value F is obtained based on the pixel Rg in the region of frame F1 and the pixel Rg in the region of frame F2 at the same position. DEGREE The operation in the flicker component estimation unit section 1 is an example of a flicker component estimation step. Flicker component value F DEGREE corresponds to the degree of flicker that occurs in the image display unit due to the pixel response delay in the pixel Rg in the region when transitioning from frame F1 to frame F2. DEGREE It is used to correct the pixel value of any focus pixel a1 included in the frame to suppress flickering during frame transition.

[0022] In addition, the flicker component value F is obtained for each pixel of interest a1 in the frame (each pixel at a predetermined coordinate in the frames F1 and F2). DEGREE That is, Figure 4 As shown in A and 4B, a plurality of focus pixels a1 are set in a frame (frames F1 and F2), and flicker component values ​​F are sequentially obtained for the focus pixels a1. DEGREE .

[0023] Furthermore, the flicker component estimation unit 1 obtains the flicker component values ​​F of an arbitrary pair of consecutive frames. DEGREE That is, the flicker component estimation unit 1 obtains each flicker component value F for correcting each focus pixel a1 of the N+1th frame based on the Nth frame (corresponding to the frame F1) and the N+1th frame (corresponding to the frame F2). DEGREE Subsequently, the flicker component estimation unit 1 obtains each flicker component value F for correcting each pixel of interest a1 of the N+2th frame based on the N+1th frame (corresponding to the frame F1) and the N+2th frame (corresponding to the frame F2). DEGREE It should be noted that N is a positive integer.

[0024] Pixel Rg in 2-1-1 area The pixel in the region Rg has one pixel of interest a1 included in each frame and surrounding pixels a2 arranged around the pixel of interest a1. That is, the pixel in the region Rg is a block of pixels composed of a plurality of pixels such as the pixel of interest a1 and the surrounding pixels a2. In addition, the pixel Rg in the region may include only one surrounding pixel a2, but in this embodiment, a more appropriate flicker component value F is obtained from DEGREE From the perspective of the embodiment, a plurality of surrounding pixels a2 may also be included. The setting range (shape) of the pixels Rg in the region is not particularly limited, but for example, it may be set to a rectangular range, such as Figure 4 A. Specifically, with respect to the size of the pixels Rg in the region, when the number of columns in the vertical direction is a and the number of columns in the horizontal direction is b, Figure 4 The pixels Rg in the area indicated by A are composed of 2 columns×5 columns of pixels.

[0025] The value of the number of columns a and the value of the number of columns b are specifically, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63. They can also be defined as being within the range between any two values ​​exemplified here. In addition, the values ​​of the number of columns a and the number of columns b and the ranges of the number of columns a and the number of columns b can be the same or different.

[0026] In addition, there is no particular limitation on setting a pixel at any coordinate of the pixel Rg in the region as the focus pixel a1. Figure 4 As shown in A, it can be set to the pixel located at the upper left corner of the pixel Rg in the region. In addition, when the values ​​of the number of columns a and the number of columns b are both odd numbers, the pixel Rg in the region has a central pixel, so the focus pixel a1 can be the central pixel. In addition, the correction process according to the embodiment does not need to be performed on all pixels of the frame F2, but may be performed within a predetermined range. In other words, all pixels in each frame do not need to be set as the focus pixel a1.

[0027] 2-1-2 Flicker component value F DEGREE The following describes how the flicker component estimation unit 1 acquires the flicker component value F. DEGREE method. With respect to the straight line (corresponding to the average pixel value of a pair of arbitrary regions connecting two consecutive frames (for example, the average pixel value of the Nth frame and the average pixel value of the N+1th frame) Figure 5 The ideal transition line L1 in the actual average value of the transition (corresponding to Figure 5 The greater the deviation from the actual transition line L2 in FIG. 1 , the greater the degree of flickering. In addition, when the average pixel value of any region of the frame is along Figure 5 When the transition line L1 shown changes, it is an ideal transition and it is difficult for humans to perceive flicker. On the contrary, if the average value of the pixel value of the frame changes like the transition line L2 and is greater than the average value of the pixel value at the beginning or end of the transition line L1, whichever is greater or less than the smaller one, humans may perceive flicker. Generally speaking, the way the average value of the pixel value of an actual frame changes varies depending on the situation, but it will deviate from the transition line L1.

[0028] Flicker component value F DEGREE The above deviation is considered. There are two viewpoints on this deviation. The first point of view is Figure 5 The area T1 ( Figure 5 In other words, the first viewpoint corresponds to the area of ​​the transition line L2 that protrudes downward from the horizontal line HL. More generally, when a rectangle is defined with the start and end of the transition line L1 as diagonal lines, the area outside the rectangle of the transition line L2 corresponds to the first viewpoint. The second viewpoint is Figure 5 The maximum distance T2 shown. The maximum distance T2 corresponds to the maximum length between the horizontal line HL and the transition line L2. Specifically, when a rectangle is defined with the starting and ending points of the transition line L1 as diagonal lines, the transition line L2 that touches the outer area of ​​the rectangle from the side of the rectangle (at Figure 5 The longest vertical line extending from the side overlapping the horizontal line HL and intersecting the transition line L2 corresponds to the second viewpoint. When the area T1 of the first viewpoint and the maximum distance T2 of the second viewpoint are larger, the degree of perceived flicker increases.

[0029] Flicker component value F according to the embodiment DEGREE is a value that takes into account the first and second viewpoints. Specifically, the flicker component value F DEGREE It is expressed by the product of the following two items (the first item and the second item), as shown in the following equation (9). In addition, the flicker component value F can be obtained based on the following equations (1) to (8): DEGREE . In the calculation methods of the first and second items described herein, with respect to the size of the pixels Rg in the region, the number of columns a in the vertical direction is 2M+1 and the number of columns b in the horizontal direction is 2N+1 (however, M and N are positive integers). The variables in the formula are as follows. (x, y) is the coordinate of the pixel in the frame (x is the horizontal direction, y is the vertical direction). f(x, y) is the pixel value of the pixel (the focus pixel a1 and the surrounding pixels a2) at the coordinates (x, y) in the next frame (frame F2). f'(x, y) is the pixel value of the pixel (the focus pixel a1 and the surrounding pixels a2) at the coordinates (x, y) in the previous frame (frame F1). ·R THRESHOLD and F THRESHOLD For the purpose of adding the value (R SUM ) and reduction value (F SUM ) is normalized to a predetermined threshold between 0 and 1. In addition, R THRESHOLD You can use R SUM The value obtained is in the range of 0.4 to 0.6 times the maximum value. THRESHOLD You can use F SUM Gets a value in the range of 0.4 to 0.6 times the maximum value. bitdepth represents the bit depth, which is the sum of CF in equations (1) and (2) AVE and PF AVE The values ​​of are normalized to values ​​between 0 and 1.

[0030]

Number 1

[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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[0036]

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[0037]

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[0038]

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[0039] 2-1-2-1 Item 1: 1-|CF AVE -PF AVE | The first term is related to the difference between the average values ​​of the pixel values ​​of frames F1 and F2 (1-|CF AVE -PF AVE |). That is, the flicker component estimation unit 1 calculates the flicker component based on the first statistical value (PF AVE ) and the second statistical value (CF AVE ) to obtain the flicker component value F DEGREE . The first statistical value (PF AVE ) is a statistical value of the pixel values ​​of the pixels Rg in the region of the frame F1, which is an average value in this embodiment. The second statistical value (CF AVE ) is the statistical value of the pixel values ​​of the pixels Rg in the area of ​​the frame F2, which is the average value in this embodiment. Among them, it is preferable that the flicker component estimation unit 1 generates a first statistical value (PF AVE ) and the second statistical value (CF AVE ) is large, reduce the flicker component value F DEGREE , and increase the flicker component value F when the difference is small DEGREE .

[0040] The first statistical value (PF AVE ) is the average value of the pixel values ​​of the pixels in the region Rg in frame F1 (previous frame), as shown in the above formula (1). In addition, it is normalized by bitdepth and takes a value between 0 and 1. The second statistical value (CF AVE ) is the average value of the pixel values ​​of the pixels in the region Rg in frame F2 (the next frame), as shown in the above formula (2). In addition, it is also normalized by bitdepth and takes a value between 0 and 1. Thus, the first item is based on CF AVE (Second Statistic) and PF AVE (the first statistical value).

[0041] like Figure 5As shown in FIG. 1 , when transitioning from frame F1 (Nth frame) to frame F2 (N+1th frame), the values ​​of the first and second viewpoints (area T1 and maximum distance T2) tend to increase as the average values ​​of the frame pixel values ​​are closer. That is, the values ​​of the first and second viewpoints tend to increase as the average value of the pixel values ​​of frame F1 of the previous frame is closer to the average value of the pixel values ​​of frame F2 of the next frame. The proximity of these average values ​​corresponds to a smaller |CF AVE -PF AVE |, thus corresponding to the larger term 1. This is equivalent to the constituent pixels of frames F1 and F2 being, for example, Figure 4 A and 4B show the case of the dot grid.

[0042] 2-1-2-2 Item 2: max(R SUM , F SUM ) The second term is a term related to the sum of the differences of the pixels whose pixel values ​​change in the region Rg when the frame F1 transitions to the frame F2 (max(R SUM , F SUM )). In addition, since it is known that R SUM and F SUM The absolute value of one or both of them is larger in a frame prone to flickering (for example, a dot grid frame). Therefore, this embodiment adopts max(R SUM , F SUM ). In addition, using only the first item, in the case of a still image or when the number of pixels added and pixels dropped is small, the first item becomes large, and the flicker component value (F DEGREE ). As a countermeasure to this, in addition to item 1, this embodiment also adopts item 2. The flicker component estimation unit 1 calculates the value of the flicker component based on the increase value (R SUM ) and reduction value (F SUM ) Get the flicker component value F DEGREE For example, when increasing the value (R SUM ) and reduction value (F SUM ) is large, increase the flicker component value (F DEGREE ). In addition, for example, when the ratio of the increase (decrease) of pixels in one direction in a still image or region is large and the first term is large, the flicker component value F DEGREE )reduce. The increase value (R) in formula (5) can be obtained using formula (3) SUM (x, y)). The increase value (R SUM (x, y)) is based on the pixel value of the pixel whose pixel value increases (increase pixel) among the pixels of the pixel Rg in the region when the frame F1 transitions to the frame F2. Specifically, the increase value (R SUM(x, y)) is the sum of the differences in pixel values ​​of frames F1 and F2 in added pixels. The reduction value (F SUM (x, y)) can be obtained from formula (4). The reduction value (F SUM (x, y)) is based on the pixel value of the pixel (decreased pixel) that is decreased among the pixels of the pixel Rg in the region when the frame F1 transitions to the frame F2. Specifically, the decreased value (F SUM (x, y)) is the sum of the differences in pixel values ​​of frames F1 and F2 in reduced pixels.

[0043] In this embodiment, as shown in equations (7) and (8), the increase value (R SUM (x, y)) and the reduction value (F SUM (x, y)) is normalized. That is, in calculating the flicker component value F in equation (9) DEGREE When using the normalized increase value (R SUM ) and reduction value (F SUM ). The larger the first term and the larger the second term, the larger the values ​​of the first and second viewpoints (area T1 and maximum distance T2) tend to be.

[0044] 2-2 Pixel value correction unit 2 The pixel value correction unit 2 is configured to correct the flicker component value F DEGREE Get the corrected pixel value p (corresponding to Figure 2 A and 2B show corrected pixel values ​​p1 to p3). In order to suppress flicker occurring in the relationship between frames F1 and F2, the corrected pixel value p is a value (pixel value) obtained by correcting the pixel value of the focus pixel a1 of frame F2. In the present embodiment, first, the pixel value correction unit 2 is configured to correct the flicker component value F1 based on the flicker component value F2. DEGREE A transition amount T described later is acquired, and a corrected pixel value p is obtained based on the transition amount T. The operation in the pixel value correction unit 2 is an example of a pixel value correction step.

[0045] In addition, the conversion amount T and the corrected pixel value p are acquired for each pixel of interest a1 included in the frame (for each pixel at a predetermined coordinate in the frame F2 ). In addition, the pixel value correction unit 2 acquires the transformation amount T and the correction pixel value p for an arbitrary pair of continuous frames. That is, the pixel value correction unit 2 acquires each transformation amount T or each correction pixel value p for correcting each pixel of interest a1 of the (N+1)th frame based on the Nth frame (corresponding to the frame F1) and the N+1th frame (corresponding to the frame F2). Subsequently, the pixel value correction unit 2 acquires each transformation amount T and each correction pixel value p for correcting each pixel of interest a1 of the N+2th frame based on the N+1th frame (corresponding to the frame F1) and the N+2th frame (corresponding to the frame F2).

[0046] 2-2-1 Transformation variable T The two purposes of obtaining the transformation variable T are explained as follows. The first purpose is to obtain a corrected pixel value p to correct the pixel value of the focus pixel a1 of the frame F2. The second purpose is to determine the pixel value of the pixel a1 of interest in the frame F1 for correction processing after the current correction processing. The determination method will be described later in the pixel value determination unit 3.

[0047] The transformation amount T of the coordinate (x, y) is as shown in the following formula (13). When the pixel value of the focus pixel a1 of the coordinate (x, y) of the next frame (frame F2) is greater than the pixel value of the focus pixel a1 of the coordinate (x, y) of the previous frame (frame F1), the transformation amount T of the formula (11) is R . In other cases, the transformation variable T of the coordinate (x, y) is T of formula (12) F In other words, the transformation amount T of the coordinate (x, y) is when the pixel value of the focus pixel a1 of the coordinate (x, y) of the next frame (frame F2) is less than the pixel value of the focus pixel a1 of the coordinate (x, y) of the previous frame (frame F1), then it is T of (12) F .

[0048] In equation (11), the flicker component value F obtained by the flicker component estimation unit 1 is used. DEGREE , CLIP function, preset value R AMP and the predetermined value R CLIP . In addition, in equation (12), the flicker component value F obtained by the flicker component estimation unit 1 is used. DEGREE , CLIP function, preset value F AMP and the predetermined value F CLIP . The CLIP function (hereinafter referred to as clipping processing) in equation (10) limits the range of values ​​that the transformation variables T (TR and TF) can take. ·R AMP is relative to the increase (R SUM ) is the amplitude parameter. R AMP Can be set to any value. ·F AMP is relative to the reduced value (F SUM ) is the amplitude parameter. AMP Can be set to any value. ·R CLIP T R Clipping processing parameters. CLIP Can be set to a value greater than -1 and less than 1. ·F CLIP T F Clipping processing parameters. CLIP Can be set to a value greater than -1 and less than 1. Clipping processing parameters R CLIP and F CLIP The positive and negative values ​​can be based on R AMP and F AMP set up.

[0049] When the transition amount T is positive, a so-called overdrive correction process is performed to accelerate the transition of the pixel value of the pixel a1 of the frame F2. On the other hand, when the transition amount T is negative, a so-called underdrive correction process is performed to slow down the transition of the pixel value of the pixel a1 of the frame F2. As an example of an overdrive correction process or an underdrive correction process, it corresponds to the equation (14) described later.

[0050]

Number 10

[0051]

Number 11

[0052]

Number 12

[0053]

Number 13

[0054] In the present embodiment, the description is made on the premise that the response speed when the pixel value of each pixel of the image display unit 20 increases is slower than the response speed when the pixel value of each pixel of the image display unit 20 decreases. On the one hand, depending on the response characteristics of the liquid crystal monitor, in some cases, the response speed when the pixel value of each pixel of the image display unit 20 increases is faster than the response speed when the pixel value of each pixel of the image display unit 20 decreases. Even in this case, when the transition amount T is positive, the so-called overdrive correction processing is performed to accelerate the transition of the pixel value of the focus pixel a1 of the frame F2. On the other hand, when the transition amount T is negative, the so-called underdrive correction processing is performed to slow down the transition of the pixel value of the focus pixel a1 of the frame F2.

[0055] 2-2-2 Correcting pixel value p The pixel value correction unit 2 can obtain the corrected pixel value p based on the following formula (14). That is, the corrected pixel value p is obtained based on the pixel value (f'(x, y)) of the focus pixel a1 of the first frame coordinate (x, y), the pixel value (f(x, y)) of the focus pixel a1 of the second frame coordinate (x, y), and the transformation amount T. Then, the pixel value correction unit 2 outputs the corrected pixel value p of each focus pixel a1 to the image display unit 20.

[0056]

Number 14

[0057] The pixel value correction unit 2 obtains the corrected pixel value p based on the pixel of interest a1 of the frame F1 (an example of the first frame) and the pixel of interest a1 of the frame F2 (an example of the second frame). In other words, the pixel value correction unit 2 obtains the corrected pixel value p based on the difference between the pixel of interest a1 of the frame F1 (an example of the first frame) and the pixel of interest a1 of the frame F2 (an example of the second frame). More specifically, the pixel value correction unit 2 obtains the corrected pixel value p based on the difference between the pixel value (f'(x, y)) of the pixel of interest a1 of the coordinates (x, y) of the frame F1 (an example of the first frame) and the pixel value (f(x, y)) of the pixel of interest a1 of the coordinates (x, y) of the frame F2 (an example of the second frame).

[0058] Furthermore, in the present embodiment, in addition to the frames F1 and F2, the correction pixel value p is obtained using the transformation amount T. That is, in the present embodiment, the pixel value correction unit 2 obtains the correction pixel value p based on the difference between the pixel value (f'(x, y)) of the attention pixel a1 at the coordinates (x, y) of the frame F1 (an example of the first frame) and the pixel value (f(x, y)) of the attention pixel a1 at the coordinates (x, y) of the frame F2 (an example of the second frame) and the transformation amount T.

[0059] In addition, when there is no difference between the focus pixel a1 of frame F1 (an example of the first frame) and the focus pixel a1 of frame F2 (an example of the second frame), the pixel value correction unit 2 may not correct the focus pixel a1 of frame F2 (an example of the second frame) which is the correction object.

[0060] 2-3 Pixel value determination unit 3 Based on the size of the transformation amount T, the pixel value determination unit 3 determines the pixel value of the focus pixel a1 of the frame F1 for the correction processing (correction processing of the Nth frame and the N+1th frame) performed after the current correction processing (correction processing of the Nth frame and the N+1th frame). In addition, d(x, y) in the following formula (15) corresponds to the pixel value determined by the pixel value determination unit 3, and the pixel value is stored in the frame memory 30. In other words, in this embodiment, the subsequent correction processing (correction processing of the N+1th frame and the N+2th frame) is not limited to using the corrected pixel value p, and the uncorrected pixel value (the pixel value of the N+1th frame itself) is used depending on the conditions.

[0061] As shown in the following formula (15), when the transition amount T is a predetermined threshold value D THRESHOLD In the above case, the pixel value determination unit 3 determines the pixel value of the attention pixel a1 of the frame F1 used in the correction process after the current correction process as the pixel value of the attention pixel a1 of the frame F2 of the current correction process. That is, the uncorrected pixel value is used. On the other hand, when the transition amount T is less than the predetermined threshold value D THRESHOLD , the pixel value determination unit 3 determines the pixel value of the focus pixel a1 of the frame F1 used in the correction process after the current correction process as the correction pixel value p obtained by the pixel value correction unit 2. That is, the corrected pixel value is used. The pixel value (correction pixel value p) determined by the pixel value determination unit 3 is an example of a transition pixel value.

[0062]

Number 15

[0063] In this way, the pixel value determination unit 3 changes the pixel value used in the subsequent correction process based on the magnitude of the transition amount T, thereby suppressing the flicker component value F in the subsequent correction process. DEGREE Reduced computational accuracy. That is, when the transition amount T is large, the transition response time in the image display unit 20 may be longer than one frame. Then, a difference is generated between the pixel value (brightness) reached by the image display unit 20 until the next frame and the pixel value (grayscale) stored in the frame memory 30. This difference may cause the flicker component value F to be larger in the correction process after the current correction process. DEGREEThe calculation accuracy is reduced. Therefore, the pixel value determination unit 3 is configured to select a pixel value to be used in the correction processing after the current correction processing based on the size of the transformation amount T. In other words, the pixel value determination unit 3 selects, based on the size of the transformation amount T, whether the pixel value (grayscale) stored in the frame memory 30 is f(x, y) (uncorrected pixel value) shown in formula (15) or p(x, y) (corrected pixel value) shown in formula (15). For example, when the pixel value (grayscale) stored in the frame memory 30 is f(x, y) shown in formula (15), the pixel value used in the image display unit 20 is the corrected pixel value p(x, y), and the pixel value stored in the frame memory 30 is different from the pixel value used in the image display unit 20. On the contrary, when the pixel value (grayscale) stored in the frame memory 30 is p(x, y) as shown in formula (15), the pixel value stored in the frame memory 30 is the same as the pixel value used by the image display unit 20.

[0064] 3 to the process of obtaining the corrected pixel value p Reference Figure 6 A to Figure 7 The process of obtaining the corrected pixel value p is described below. Note that in this embodiment, the bit depth described here is 8. like Figure 6 As shown in A, the pixels Rg in the region of the Nth frame corresponding to the frame F1 include the focus pixel a1 set at the center and 8 surrounding pixels a2 set to surround it. The pixel value of each pixel in the region Rg is Figure 6 The value shown in A changes to Figure 6 B. For example, the pixel of interest a1 increases from 50 to 128. That is, the pixel of interest a1 is an increased pixel. In addition, for example, the four surrounding pixels a2 (pixels with underlined numbers) increase from 0 to 100, from 0 to 150, from 0 to 255, and from 0 to 200. That is, these four surrounding pixels a2 are also increased pixels.

[0065] Use the above formula to estimate the flicker component value F DEGREE . The first term ((1-|CF AVE -PF AVE |)) is as follows. CF AVE For use Figure 6 The values ​​shown in B are calculated. CF AVE =(0+100+0+150+128+255+0+200+0) / (3×3×255)≒0.36 PF AVE For use Figure 6The values ​​shown in A are calculated. PF AVE =(255+0+100+0+50+0+150+0+255) / (3×3×255)≒0.35 Therefore, (1-|CF AVE -PF AVE |)=(1-|0.36-0.35|)=0.99

[0066] Item 2 (max(R SUM , F SUM ))as follows. R SUM is used Figure 6 A and Figure 6 B shows the numerical difference calculation of the added pixels (pixels with numbers underlined). R SUM =(100+150+78+255+200) / (3×3×255)≒0.34 F SUM is used Figure 6 A and Figure 6 Numerical difference calculations for reduced pixels (pixels whose numbers are not underlined) are shown in B. F SUM =(255+100+150+255) / (3×3×255)≒0.33 Therefore, max(R SUM , F SUM )=0.34

[0067] Based on the above calculation, F DEGREE =0.99×0.34≒0.3 Next, the transformation amount T is calculated. Here, the focus pixel a1 is the added pixel. Therefore, based on the condition of equation (13), the transformation amount T is T of equation (11): R .

[0068] Based on formula (11), T(=T R )as follows. T=T R = CLIP(F DEGREE ×R AMP , R CLIP ) = CLIP (0.3 × 1, 1) = 0.3 Among them, R AMP and R CLIP Both are 1.

[0069] Then, by Figure 6 By substituting the pixel value of the focus pixel a1 in A and 6B into equation (14), the corrected pixel value p of the focus pixel a1 at the coordinates (x, y) can be obtained. p=128+((128-50)×0.3)≒151 That is, Figure 7 As shown, the pixel value of the focus pixel a1 in the N+1th frame (frame F2) is corrected from 128 to 151. In this example, since the response speed when the pixel value increases is slower than the response speed when the pixel value decreases, the focus pixel a1 with increased pixel value is subjected to overdrive correction processing.

[0070] 4. Effects of Implementation The pixel value correction unit 2 is configured to correct the flicker component value F DEGREE Get the corrected pixel value p. Flicker component value F DEGREE The value of the flicker component value F1 is not only based on the pixel value of the attention pixel a1 in the frames F1 and F2, but also based on the pixel values ​​of the surrounding pixels a2 arranged around the attention pixel a1. DEGREE Since the value takes into account the content (type) of the frames F1 and F2, the corresponding corrected pixel value p is also a value taking into account the content of the first frame and the second frame. For example, when a pure white frame (e.g., maximum pixel value) is changed to a pure black frame (e.g., minimum pixel value), flickering is not likely to occur. Even in this case, if the technique as in Patent Document 1 is uniformly applied, it will unnecessarily slow down the response speed of the pixel, thus causing image quality degradation, such as the appearance of afterimages and overshoot and undershoot of brightness.

[0071] In contrast, in the correction process according to the present embodiment, when a pure white frame (pixel value is 255) is changed to a pure black frame (pixel value is 0), the flicker component value F DEGREE is 0 and the corrected pixel value p is also 0, so the pixel value does not change, an unnecessary decrease in pixel response speed can be avoided, and a decrease in image quality can be suppressed. In addition, for frames that are prone to flickering, you can use the reference above Figure 6 A to Figure 7 The corrected pixel value p is used to suppress flicker. Figure 6 A and 6B are prone to flickering. If the correction process is performed, the area T1 will be as shown in FIG. Figure 5 As shown, the area T1 increases and flickering is likely to occur. In contrast, in the embodiment, the area T1 is reduced by correction processing, or the average value of the pixel value is shifted to protrude upward from the transition line L1, thereby playing a role in canceling the area T1 (integration effect). This can suppress the occurrence of flickering.

[0072] 5. Modification 5-1 Variation 1: Statistical Values In this embodiment, the first statistical value (PF AVE ) and the second statistical value (CF AVE ), the average value of the pixel values ​​of the pixels Rg in the region of frames F1 and F2 is used, but it is not limited to this. Instead of the average value, the dispersion value of the pixels Rg in the region of frames F1 and F2, the median value of the pixels Rg in the region of frames F1 and F2, or the low-frequency component value of the pixels Rg in the region of frames F1 and F2 may be used. In addition, the low-frequency component value is a weighted value in the probability density distribution corresponding to at least one of the inter-pixel distance and the pixel value of the pixel Rg in the region.

[0073] 5-2 Modification 2: Flicker component value F DEGREE Item 2 In this embodiment, max(R SUM , F SUM ) is used to calculate the flicker component value F DEGREE , but not limited to this. Even if min(R SUM , F SUM ) instead of max(R SUM , F SUM ), the same functions and effects as those in the implementation method can also be obtained. In addition, instead of max(R SUM , F SUM ), using max(R SUM , F SUM ) and min(R SUM , F SUM ) between the values, the same functions and effects as those in the embodiment can also be obtained. SUM , F SUM )+min(R SUM , F SUM )} / 2 Generally, use R SUM and F SUM The value corresponding to the average value of . Alternatively, (α×R SUM +β×F SUM ) / (α+β) is generally used for R SUM and F SUM The value of the weight of flicker sensitivity is set (α and β are values ​​greater than or equal to 0). In this way, based on R SUM and F SUM The value of can also be used to calculate the flicker component value F DEGREE .

[0074] 5-3 Variation 3: Transforming pixel values In the present embodiment, the pixel value determination unit 3 uses the correction pixel value p as the transition pixel value when the transition amount T is less than a predetermined threshold value, but the invention is not limited thereto. For example, the transition pixel value may be the correction pixel value p obtained in the current correction process, the pixel value of the focus pixel a1 (the pixel value before correction itself) in the frame F2 of the current correction process, or a value between the two. Note that the value between the two is a value between the correction pixel value p obtained in the current correction process and the pixel value of the focus pixel a1 (the pixel value before correction itself) in the frame F2 of the current correction process.

[0075] 5-4 Modification 4: Relationship between the Image Processing Unit 10 and the Image Display Unit 20 In this embodiment, the image processing unit 10, the frame memory 30, and the image display unit 20 are described as being integrated (described as being accommodated in the same frame), but the present invention is not limited thereto. The image processing unit 10 and the frame memory 30 may be separated from the image display unit 20. In other words, the image processing unit 10 and the frame memory 30 may be provided in separate and different frames from the image display unit 20.

[0076] 5-5 Modification 5: Method without pixel value determination unit 3 In the embodiment, the image processing device 100 is described as having the pixel value determination unit 3, but the pixel value determination unit 3 is not an essential configuration. Figure 8 As shown, the image processing apparatus 100 may not include the pixel value determination unit 3. In this case, the pixel value d1 (x, y) is not the pixel value determined by the pixel value determination unit 3 but the pixel value itself of each frame. For example, Figure 8 As shown, when the frame F2 is input to the image processing device 100, the frame F2 is output not only to the flicker component estimation unit 1 but also to the frame memory 30 and is stored in the frame memory 30. DEGREE When the input frame F2 and the frame F1 stored in the frame memory 30 are used.

[0077] 5-6 Modification 6: Each component is stored in a separate device In this embodiment, the configuration for storing a video signal (output device 200) and the configuration for displaying a video signal (image processing device 100) are described as separate entities, but the present invention is not limited thereto, and these configurations may be integrated. Furthermore, in this embodiment, the image processing device 100 is described as including the image display unit 20 , but the present invention is not limited thereto, and the image processing device 100 may not include the image display unit 20 . Explanation of symbols

[0078] 1: Flicker component estimation unit 2: Pixel value correction unit 3: Pixel value determination unit 10: Image processing unit 20: Image display unit 30: Frame memory 100: Image processing device 200: Output device.

Claims

1. An image processing device that performs correction processing for correcting the second frame based on a first frame and a second frame, It is equipped with a flicker component estimation unit and a pixel value correction unit. The flicker component estimation unit is configured to obtain a flicker component value based on pixel values ​​of pixels in the area of ​​the first frame and the second frame. The pixels in the region are composed of a plurality of pixels included in a predetermined region of the first frame and the second frame. The plurality of pixels include a focus pixel and surrounding pixels arranged around the focus pixel. The flicker component value corresponds to the degree of flicker that occurs in the image display unit due to pixel response delay of pixels in the area when transitioning from the first frame to the second frame. The pixel response delay corresponds to a difference in response speed between the increasing pixels whose pixel values ​​increase and the decreasing pixels whose pixel values ​​decrease among the plurality of pixels when transitioning from the first frame to the second frame. The pixel value correction unit is configured to obtain a corrected pixel value based on the flicker component value. The corrected pixel value is a value obtained by correcting the pixel value of the focus pixel in the second frame.

2. The image processing device according to claim 1, wherein: The flicker component estimation unit obtains the flicker component value based on a difference between the first statistical value and the second statistical value, The first statistical value is a statistical value of the pixel values ​​of the plurality of pixels in the area of ​​the first frame, The second statistical value is a statistical value of the pixel values ​​of the plurality of pixels in the region of the second frame.

3. The image processing device according to claim 2, wherein: The statistical value is an average value, a dispersion value, a median value or a low-frequency component value of the pixel values ​​of the plurality of pixels in the pixel area, The low-frequency component value is a weighted value in a probability density distribution based on at least one of an inter-pixel distance and a pixel value.

4. The image processing device according to any one of claims 1 to 3, wherein: The flicker component estimation unit acquires the flicker component value based on the increase value and the decrease value, The increase value is based on the pixel value of the increase pixel among the plurality of pixels when transitioning from the first frame to the second frame, The reduced value is based on the pixel value of the reduced pixel among the plurality of pixels when transitioning from the first frame to the second frame.

5. The image processing device according to claim 4, wherein: The added value is the sum of the differences between the pixel values ​​of the first frame and the second frame in the added pixel. The reduced value is the sum of the differences between the pixel values ​​of the first frame and the second frame in the reduced pixel.

6. The image processing device according to any one of claims 1 to 3, Also provided is a pixel value determination unit, The pixel value correction unit is configured to obtain a transition amount based on the flicker component value, and obtain the corrected pixel value based on the transition amount. The pixel value determination unit determines the pixel value of the pixel of interest of the first frame used in a correction process subsequent to a current correction process based on the size of the transition amount.

7. The image processing device according to claim 6, wherein: When the transition amount is greater than a predetermined threshold, the pixel value determination unit uses the pixel value of the focus pixel of the first frame used in the correction process after the current correction process as the pixel value of the focus pixel of the second frame of the current correction process, When the transition amount is less than the predetermined threshold, the pixel value determination unit uses the pixel value of the focus pixel of the first frame used in the correction process after the current correction process as the transition pixel value, The transition pixel value is the correction pixel value acquired in the current correction process, the pixel value of the focus pixel in the second frame of the current correction process, or a value between the two.

8. The image processing device according to any one of claims 1 to 3, further comprising the image display unit, The image display unit is configured to display a frame reflecting the corrected pixel value acquired by the pixel value correction unit.

9. An image processing method, comprising: performing a correction process for correcting the second frame based on a first frame and a second frame subsequent to the first frame, The image processing method comprises a flicker component estimation step and a pixel value correction step. In the flicker component estimation step, a flicker component value is obtained based on pixel values ​​of pixels in the area of ​​the first frame and the second frame. The pixels in the region are composed of a plurality of pixels included in a predetermined region of the first frame and the second frame. The plurality of pixels include a focus pixel and surrounding pixels arranged around the focus pixel. The flicker component value corresponds to the degree of flicker that occurs in the image display unit due to pixel response delay within the pixels in the area when transitioning from the first frame to the second frame. The pixel response delay corresponds to a difference in response speed between the increasing pixels whose pixel values ​​increase and the decreasing pixels whose pixel values ​​decrease among the plurality of pixels when transitioning from the first frame to the second frame. In the pixel value correction step, a corrected pixel value is obtained based on the flicker component value, The corrected pixel value is a value obtained by correcting the pixel value of the focus pixel in the second frame.

10. A program for causing a computer to execute the image processing method according to claim 9.

Images