JP2012098559A - Image processing device and image processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing device that employs a technology for preventing luminance suppression and increase in unnecessary power consumption in a display device, and reducing difference in brightness between display devices in a multi-display system.SOLUTION: A coefficient for brightness value correction that corresponds to APL in a second area and an average brightness value of a boundary pixel string, is multiplied by an updated color component value of respective pixels that constitute the boundary pixel string. ΔS=(APL2×n-Ave×p)/(n-p) is subtracted from a color component value of respective pixels other than those constituting the boundary pixel string in the second area to update the color component value of respective pixels.

Description

  The present invention relates to an image display technique.

  In recent years, a large screen of a flat-screen television such as a PDP has been increased. About 30 to 70 inches of products are distributed on home TV. In particular, in a PDP suitable for a large screen, a large screen product of 100 inches or more is commercialized and used as a commercial display.

  Another technique is the multi-output of a graphics card. This technique is also called multi-display or multi-monitor, and two or more displays can be connected to one computer and displayed as if it were one large display. Recently, there are some graphics cards that can display four displays. In such a multi-display using a large screen display or a graphics card, it is possible to make a large screen exceeding 200 inches.

  The power consumption of the display increases due to the large screen. However, the power consumption of the self-luminous large screen display such as the aforementioned PDP or the FED that has been developed in recent years varies greatly depending on the image. Therefore, these displays usually have a loading function for controlling the maximum value of the voltage in accordance with the displayed Average Pixel Level (hereinafter referred to as APL: pixel average information) for the purpose of reducing power consumption. On the other hand, when the input image is divided and displayed on the multi-display, the APL assigned to each display is different. For this reason, there is a problem that the brightness is different between adjacent displays even with the same pixel value.

  As a method for solving the above problem, as disclosed in Patent Document 1, there is a method in which the APL of each display is transmitted from the display, the APLs of all the displays are compared, and then a specific APL is reset to all the PDPs.

  As another method, as disclosed in Patent Document 2, there is a method in which divided image information and APL information common to all displays are transmitted simultaneously to unify the APL of all displays.

  As another method, as disclosed in Patent Document 3, the APL before and after the division is calculated, any APL and the divided image are transmitted to all PDPs according to the input image, and the APL of all displays is unified. There is a way. According to these methods, it is possible to match the brightness between adjacent displays.

JP 2002-006804 A JP 2003-015623 A JP 2004-226513 A

  However, in any of the aforementioned Patent Documents 1 to 3, an APL different from the APL of the image information that is actually displayed may be set. For example, when APL is set higher than the APL of the image, the peak luminance of the display is limited to be low, and the luminance of the display is suppressed. Further, when APL is set lower than the APL of the image, the peak luminance of the display becomes high, and the power consumption of the display increases.

  In the case of Patent Document 1, since the APL must be transmitted back from the panel side, there is a problem that the cost of the panel increases. In Patent Documents 2 and 3, since information other than image information is transmitted, there is a problem that the cost of the system increases.

  The present invention has been made in view of the above problems, and a technique for reducing brightness differences among display devices in a multi-display while avoiding luminance suppression and unnecessary power consumption increase in the display device. The purpose is to provide.

  In order to achieve the object of the present invention, for example, an image processing apparatus of the present invention comprises the following arrangement. That is, a dividing unit that divides the image into a first area for displaying one image on one display device and a second area for displaying on one display device, the first area, Pixels for which a difference in luminance value is obtained for each pixel pair between the pixel on the first region side and the pixel on the second region side adjacent to the boundary with the second region, and the obtained difference is smaller than a threshold value Means for specifying a pixel pair row in which pairs are continuously arranged, specifying a pixel group in the second region as a boundary pixel row in the specified pixel pair row, and color components in the first region APL is obtained using a value, APL is obtained using a color component value in the second region, APL in the second region is a denominator, and APL in the first region is a numerator The calculated fractional value is used as the color component value of each pixel constituting the boundary pixel row. And updating the color component value of each pixel, and among the luminance value correction coefficients preset for each different APL and each different luminance value, the APL in the second region and the Update means for specifying a luminance value correction coefficient corresponding to the average luminance value of the boundary pixel column, and multiplying the updated luminance component value of each pixel constituting the boundary pixel column by the specified luminance value correction coefficient; APL2 in the second region is APL2, n is the total number of pixels in the second region, p is the number of pixels constituting the boundary pixel column, and the updating means for each pixel constituting the boundary pixel column If the average luminance value calculated from the color component values updated in step A is Ave, means for calculating ΔS = (APL2 × n−Ave × p) / (np), and the boundary in the second region ΔS from the color component value of each pixel other than the pixel column Means for updating the color component value of each pixel by subtraction.

  According to the configuration of the present invention, it is possible to avoid luminance suppression in the display device and unnecessary increase in power consumption, and to reduce the brightness difference between the display devices in the multi-display.

1 is a block diagram illustrating a configuration example of an image processing apparatus. FIG. 3 is a block diagram illustrating a configuration example of a correction processing circuit 110. FIG. 3 is a block diagram illustrating a configuration example of an image dividing unit 202. The figure which shows the relationship of Dcol, Drawing, Icol, and Irow in the case of m1 = m2 = 2. The figure which shows the relationship between Dcol, Drawing, Icol, and Irow after a scaling process in the case of m1 = m2 = 2. The block diagram which shows the structural example of the continuous area extraction part 203. FIG. The figure which shows an example of the divided image 1 and the divided image 2. FIG. The figure which shows an example of table information. The figure which shows the structural example of the brightness correction | amendment part 207. FIG. The figure which shows the structural example of the feature correction amount calculation part 205. FIG. The figure which shows the relationship between each APL and the largest output luminance value. 10 is a flowchart of processing performed by the correction processing circuit 110.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. The embodiment described below shows an example when the present invention is specifically implemented, and is one of the specific examples of the configurations described in the claims.

[First Embodiment]
First, a configuration example of the image processing apparatus according to the present embodiment will be described with reference to the block diagram of FIG. The image processing apparatus according to the present embodiment divides one image (an image of each frame in the case of a moving image) based on a video signal supplied from the outside into a plurality of areas, and each divided image is divided. , Output to the same number of display devices as the number of divisions. Thus, the single image is displayed on the plurality of display devices.

  The analog broadcast input terminal 101 is a terminal for inputting analog broadcast signals such as terrestrial analog broadcast and satellite analog broadcast. The analog external input terminal 102 is a terminal for inputting an analog video signal, such as a D terminal. The digital broadcast input terminal 103 is a terminal for inputting digital broadcast signals such as terrestrial digital broadcast and satellite digital broadcast. The digital external input terminal 104 is a terminal for inputting a digital video signal such as HDMI.

  The analog tuner 105 is a device for converting an analog broadcast signal input via the analog broadcast input terminal 101 into a video signal. The digital tuner 106 is a device for converting a digital broadcast signal input via the digital broadcast input terminal 103 into a video signal.

  The A / D converter 107 is a device for converting an analog video signal input via the analog tuner 105 or the analog external input terminal 102 into a digital video signal. The decoder 108 is a device for decoding a video signal encoded by an encoding technique such as MPEG input via the digital tuner 106 or the digital external input terminal 104 into a reproducible decoded video signal.

  The selector 109 selects one of the A / D converter 107 and the decoder 108 and supplies a video signal output from the selected one to the correction processing circuit 110 at the subsequent stage. The correction processing circuit 110 is a device that performs image processing such as image quality improvement and correction on the video signal supplied via the selector 109 based on given parameters.

  The CPU 111 controls the operation of the entire image processing apparatus using computer programs and data stored in the ROM 112, and also controls the operation of the above-described units constituting the image processing apparatus.

  The ROM 112 stores a computer program and data for causing the CPU 111 to perform operation control of the entire image processing apparatus, and a computer program and data for causing the CPU 111 to execute each process described later as what the image processing apparatus performs. . The ROM 112 also stores setting data for the image processing apparatus. Computer programs and data stored in the ROM 112 are appropriately loaded into the RAM 113 under the control of the CPU 111 and are processed by the CPU 111.

  The RAM 113 has an area for temporarily storing various data, a work area used when the CPU 111 executes various processes, and the like. That is, the RAM 113 can provide various areas as appropriate.

  The operation unit 114 is for inputting various instructions to the CPU 111 by an operator of the image processing apparatus. The operation unit 114 includes buttons as real objects, touch panel type input devices provided on the panels (displays) 115 to 117, and the like.

  Panels 115 to 117 are used to display one image that has been subjected to image processing by correction processing circuit 110. For example, when one image is vertically divided into three equal parts, the left image may be displayed on the panel 115, the middle image may be displayed on the panel 116, and the right image may be displayed on the panel 117. In FIG. 1, the number of panels is three. However, as will be apparent from the following description, the number of panels may be any number as long as it is plural.

  Next, a configuration example of the correction processing circuit 110 will be described with reference to the block diagram of FIG. In the following description, a well-known APL is used as the image feature amount, but it will be apparent from the following description that other features may be used.

<Operation of the high-quality image conversion unit 201>
The high image quality conversion unit 201 performs preprocessing such as noise reduction, I / P conversion, resolution conversion, γ correction, contour correction, and panel-dependent processing on the video signal supplied from the selector 109. The received video signal is sent to the subsequent image dividing unit 202.

<Operation of Image Dividing Unit 202>
The image dividing unit 202 divides one image represented by the video signal supplied from the high image quality converting unit 201 into the same number of regions as the number of panels. In the case of FIG. 1, since the number of panels is 3, one image represented by the video signal supplied from the high image quality conversion unit 201 is divided into three regions. Further, the size of the single image may be appropriately scaled before the area division.

  Here, the operation of the image dividing unit 202 will be described in more detail. As shown in the block diagram of FIG. 3, the image dividing unit 202 includes a resolution conversion unit 301 and an image allocation unit 302.

  The resolution conversion unit 301 acquires the number of panels connected to the image processing apparatus from the CPU 111 or the like. There are various methods for counting the number of panels connected to the image processing apparatus, such as counting by the CPU 111 at the time of connection. Since this is a well-known technique, description thereof will be omitted.

  Here, it is assumed that a total of m1 × m2 panels, m1 in the vertical direction and m2 in the horizontal direction, are two-dimensionally arranged and connected to the image processing apparatus. Further, the vertical pixel number of the screen of each panel is Dcol, and the horizontal pixel number is Drow.

  In this case, the resolution conversion unit 301 is such that the vertical size (number of pixels) Icol and the horizontal pixel number Irow of the image (input image) represented by the video signal supplied from the high image quality conversion unit 201 satisfy the following expressions: The vertical and / or horizontal size of the input image is scaled so as to be the size.

Icol = m1 × Dcol
Irow = m2 × Drow
Various methods such as nearest neighbor, bicubic, and bilinear can be used for this magnification. FIG. 4 shows the relationship between Dcol, Draw, Icol, and Irow when m1 = m2 = 2. FIG. 5 shows the relationship between Dcol, Draw, Icol, and Irow after the above scaling process in the case of m1 = m2 = 2. By such a scaling process, the size of one input image can be matched with the total size of the display screens of the respective panels. Next, the image allocating unit 302 divides the input image into m1 × m2 areas by dividing the input image after scaling by m1 vertically and m2 horizontally.

<Operation of Continuous Region Extraction Unit 203>
Next, the operation of the continuous area extraction unit 203 will be described. The continuous area extraction unit 203 includes a reference luminance calculation unit 601, a luminance comparison unit 602, and a continuous area information calculation unit 603, as shown in the block diagram of FIG.

  Further, in the following description, the case where the image dividing unit 202 divides the input image into two divided images (regions) will be described. However, the essence of the following description is not limited to this, from the following description. It will be clear.

  The division into two divided images means that the number of panels connected to the image processing apparatus is 2, so that one divided image is displayed on one panel and the other panel is on the other. A divided image is displayed. In the following description, one panel is referred to as panel 1 and the other panel is referred to as panel 2, the divided image displayed on panel 1 is divided image 1 (first region), and the divided image displayed on panel 2 is divided image. 2 (second region). In the following, the divided image 1 is displayed on the panel 1 as it is, and the divided image 2 is displayed on the panel 2 after being corrected as follows.

  First, the reference luminance calculation unit 601 calculates the luminance value of each pixel constituting the pixel row Y1 for the pixel row Y1 adjacent to the divided image 2 on the input image in the pixel group constituting the divided image 1. . Since each pixel has a pixel value (color component value) of R, G, and B, the luminance value of the pixel can be obtained by calculating the following equation.

Y = α × R + β × G + γ × B
Here, α, β, and γ are constants. When the color space of the image is sRGB, α = 0.2126, β = 0.7152, and γ = 0.0722. Of course, the method of calculating the luminance value is not limited to this.

  In addition, the reference luminance calculation unit 601 similarly sets the luminance value of each pixel constituting the pixel row Y2 for the pixel row Y2 adjacent to the divided image 1 on the input image in the pixel group constituting the divided image 2. Ask.

  FIG. 7 shows the divided image 1 and the divided image 2, and the pixel columns Y1 and Y2 in the respective divided images are shown in gray. Further, a boundary portion where the divided image 1 and the divided image 2 are adjacent to each other is indicated by a dotted line.

  The luminance comparison unit 602 includes luminance values of pixels x (x = 1,..., XY: total number of pixels constituting the pixel column Y1 (Y2)) constituting the pixel column Y1 and pixels constituting the pixel column Y2. A difference (absolute value) DF (x) between the luminance value of x is obtained. The luminance comparison unit 602 compares the obtained difference DF (x) with the threshold value ΔY stored in the ROM 112 in advance. This threshold value ΔY may be a luminance discrimination interval amount based on Weber-Fechner. Further, the threshold value ΔY may be an amount such that ΔY is a Lab color difference and an AA class tolerance (ΔE = 0.8 to 1.6). Further, the threshold value ΔY may be an amount such that ΔY becomes a class A tolerance (ΔE = 1.6 to 3.2) by Lab color difference. Further, the threshold value ΔY may be an amount such that ΔY is equal to Lab color difference and ΔE = 1.

  The luminance comparison unit 602 sets 1 to the flag FL (x) if DF (x) <ΔY, and sets 0 to the flag FL (x) if DF (x) ≧ ΔY. Such processing is performed for each x satisfying x = 1,..., XY.

  Then, the luminance comparison unit 602 identifies a section of x satisfying the flag FL (x) = 1, and selects a pixel column composed of pixels at positions indicated by x in the identified section among the pixels constituting the pixel column Y2. , Specified as a boundary pixel column.

  That is, the processing performed by the brightness comparison unit 602 so far is, in other words, the following processing. First, a luminance value difference DF (x) is obtained for each pixel pair of a pixel on the first region side and a pixel on the second region side adjacent to the boundary between the first region and the second region. Then, a pixel pair row in which pixel pairs having the obtained difference DF (x) smaller than the threshold value ΔY are continuously arranged is specified. Then, the pixel group in the second region in the specified pixel pair column is specified as the boundary pixel column. The continuous area information calculation unit 603 calculates the average luminance value using the luminance value of each pixel constituting the boundary pixel column.

<Operation of Feature Correction Amount Calculation Unit 205>
Next, the operation of the feature correction amount calculation unit 205 will be described. The feature correction amount calculation unit 205 includes a feature amount calculation unit 1001 and a feature correction amount search unit 1002, as shown in the block diagram of FIG.

  The feature amount calculation unit 1001 calculates the average value of the G pixel values of each pixel in the divided image 1 (in the first region) as the APL (APL1) of the divided image 1. Similarly, the feature amount calculation unit 1001 calculates the average value of the G pixel values of each pixel in the divided image 2 (in the second region) as the APL (APL2) of the divided image 2. Of course, the APL calculation method is not limited to this.

  First, the feature correction amount search unit 1002 acquires the table information shown in FIG. 8 stored in the display characteristic information DB 204. In the table information of FIG. 8, output luminance values for each input luminance value are registered for each different APL. For example, when APL = 16, even if a signal value = 16 is input as an input luminance value, only a luminance value of 0.22 is output. Even if signal value = 255 is input as the maximum input luminance value, only 100 luminance values are output. The relationship between each APL and the maximum output luminance value is shown in FIG. Such table information is created in advance as display characteristic information of the panel 2 and stored in the display characteristic information DB 204.

  However, the feature correction amount search unit 1002 specifies the maximum output luminance value for the calculated APL2 from the table information of FIG. 8, and the average luminance value calculated by the continuous region information calculation unit 603 is greater than the maximum output luminance value. Judge whether it is small or not. If it is smaller, the feature correction amount search unit 1002 calculates a fractional value Gain (= APL2 / APL1) with APL1 as the denominator and APL2 as the numerator.

  When the average luminance value calculated by the continuous area information calculation unit 603 is equal to or greater than the maximum output luminance value, the feature correction amount search unit 1002 performs APL such that the average luminance value is smaller than the maximum output luminance value. It is acquired from the table information of FIG. 8, and it is set as APL2, and Gain is calculated.

<Operation of Feature Correction Unit 206>
Next, the operation of the feature correction unit 206 will be described. The feature correction unit 206 multiplies the fractional value Gain by the pixel values of R, G, and B of each pixel that forms the boundary pixel sequence (continuous region information), so that the R of each pixel that configures the boundary pixel sequence. , G, B pixel values are updated.

<Operation of Brightness Correction Unit 207>
Next, the operation of the brightness correction unit 207 will be described. As shown in the block diagram of FIG. 9, the luminance correction unit 207 includes a continuous area determination unit 1301, a first correction unit 1302, a feature maintenance parameter calculation unit 1303, and a second correction unit 1304.

  The continuous area determination unit 1301 refers to each pixel constituting the divided image 2 and determines whether it belongs to the boundary pixel column. Since the position of each pixel constituting the boundary pixel column can be determined by the above processing, this determination process is performed by comparing the position of each pixel constituting the divided image 2 with the position of each pixel constituting the boundary pixel column. Can be achieved.

  Here, when the reference pixel that is currently referred to in the divided image 2 is a pixel that forms a boundary pixel row, the R, G, and B pixel values of the reference pixel are sent to the first correction unit 1302. . On the other hand, when the reference pixel currently referred to in the divided image 2 is not a pixel constituting the boundary pixel column, the R, G, and B pixel values of the reference pixel are sent to the second correction unit 1304.

  The first correction unit 1302 specifies a luminance value correction coefficient corresponding to the average luminance value of APL2 and the boundary pixel column among the luminance value correction coefficients set in advance for each different APL and each different luminance value. . The “brightness value correction coefficient set in advance for each different APL and each different brightness value” is registered in advance in a memory such as the ROM 112. Then, the first correction unit 1302 multiplies the R, G, and B pixel values received from the continuous region determination unit 1301 by the specified luminance value correction coefficient, respectively, thereby calculating the R, G, and B pixel values. Update.

  The feature maintenance parameter calculation unit 1303 updates the total number of pixels in the divided image 2 to n, the number of pixels constituting the boundary pixel column to p, and the pixels constituting the boundary pixel column (by the first correction unit 1302). The following formula is calculated by setting Ave as the average luminance value calculated from the color component values.

ΔS = (APL2 × n−Ave × p) / (n−p)
The second correction unit 1304 subtracts ΔS from the R, G, and B pixel values of each pixel other than the boundary pixel column in the divided image 2. As described above, the R, G, and B pixel values of the boundary pixel column are corrected by the first correction unit 1302, and the R, G, and B pixel values of pixels other than the boundary pixel column are corrected by the second correction unit 1304. The divided image 2 can be obtained. However, the correction processing circuit 110 outputs the divided image 2 corrected in this way to the panel 2.

  As described above, according to the present embodiment, it is not necessary to fix the feature values of all the panels in a specific state, and the brightness between the panels can be minimized by changing the feature values of each panel as necessary. Make corrections. Therefore, it is possible to correct the difference in brightness between the panels while suppressing the performance of the panels and suppressing an increase in power consumption. Furthermore, since only image information is transmitted, it is possible to correct brightness differences between panels without increasing the system cost.

  Each process described above will be described with reference to the flowchart of FIG. Since the process in each step is as described above, the process in each step will be briefly described here. Each main body that executes the processing according to the flowchart of FIG. 12 operates based on operation control by the CPU 111.

  First, in step S <b> 1201, the high image quality conversion unit 201 performs various kinds of preprocessing as described above on the video signal supplied from the selector 109, and sends it to the subsequent image division unit 202.

  In step S1202, the image dividing unit 202 adjusts the size of one image represented by the video signal supplied from the high image quality converting unit 201 to the total size of the display screens of the panel 1 and the panel 2 in order to match the size of the image. Perform scaling processing. The image dividing unit 202 divides the scaled image into a divided image 1 and a divided image 2.

  In step S <b> 1203, the continuous area extraction unit 203 specifies a boundary pixel string for the divided image 2. The continuous area extraction unit 203 calculates an average luminance value using the luminance value of each pixel constituting the boundary pixel row. In step S1204, the feature correction amount calculation unit 205 calculates APL1 and APL2. Further, the feature correction amount calculation unit 205 calculates the fractional value Gain.

  In step S1205, the feature correction unit 206 multiplies the fractional value Gain by the pixel values of R, G, and B of each pixel that configures the boundary pixel column, so that the R, The pixel values of G and B are updated.

  In step S1206, the luminance correction unit 207 corrects the R, G, and B pixel values of the pixels constituting the boundary pixel column by multiplying the luminance value correction coefficient. In step S1207, the luminance correction unit 207 calculates the above ΔS, and corrects the R, G, and B pixel values of the pixels other than the boundary pixel column in the divided image 2 using the ΔS.

[Second Embodiment]
Each part of the correction processing circuit 110 shown in FIG. 1 may be configured by hardware, but a part or all of it may be implemented as a computer program. In this case, the computer program is stored in a memory such as the ROM 112. Then, the CPU 111 executes this computer program, thereby realizing the function of the corresponding functional unit.

(Other examples)
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, or the like) of the system or apparatus reads the program. It is a process to be executed.

Claims (3)

A dividing unit that divides the image into a first area for displaying one image on one display device and a second area for displaying on one display device;
The difference obtained by obtaining a difference in luminance value for each pixel pair of the pixel on the first region side and the pixel on the second region side adjacent to the boundary between the first region and the second region. Means for specifying a pixel pair row in which pixel pairs having a threshold value smaller than a threshold value are continuously arranged, and specifying a pixel group in the second region in the specified pixel pair row as a boundary pixel row;
Means for determining APL using the color component values in the first region and determining APL using the color component values in the second region;
Calculating a fractional value using the APL in the second region as a denominator and the APL in the first region as a numerator, and multiplying the calculated fractional value by a color component value of each pixel constituting the boundary pixel column; And a means for updating the color component value of each pixel,
Among the luminance value correction coefficients set in advance for each different APL and for each different luminance value, specify the luminance value correction coefficient corresponding to the APL in the second area and the average luminance value of the boundary pixel column Updating means for multiplying the specified luminance value correction coefficient by the updated color component value of each pixel constituting the boundary pixel column;
APL2 in the second region is APL2, n is the total number of pixels in the second region, p is the number of pixels constituting the boundary pixel column, and the updating means for each pixel constituting the boundary pixel column A means for calculating ΔS = (APL2 × n−Ave × p) / (n−p), where Ave is the average luminance value calculated from the color component values updated in step S;
An image processing apparatus comprising: means for updating the color component value of each pixel by subtracting ΔS from the color component value of each pixel other than the boundary pixel column in the second region.   When the average luminance value is equal to or greater than the maximum output luminance value of the other display device in the APL in the second region, the updating means replaces the APL with the average luminance value being the maximum output luminance. The image processing apparatus according to claim 1, wherein an APL that is smaller than a luminance value and a luminance value correction coefficient corresponding to an average luminance value of the boundary pixel column are specified. An image processing method performed by an image processing apparatus,
A dividing step in which the dividing means of the image processing device divides the image into a first region for displaying one image on one display device and a second region for displaying on one display device; ,
The specifying unit of the image processing apparatus determines luminance for each pixel pair of the pixel on the first area side and the pixel on the second area side adjacent to the boundary between the first area and the second area. A value difference is obtained, a pixel pair row in which pixel pairs having the obtained difference smaller than a threshold value are continuously arranged is specified, and a pixel group in the second region in the specified pixel pair row is defined as a boundary pixel row. A process identified as
The calculating means of the image processing apparatus calculates APL using the color component values in the first area and calculates APL using the color component values in the second area;
The updating means of the image processing apparatus calculates a fractional value using the APL in the second region as a denominator and the APL in the first region as a numerator, and the calculated fractional value is configured in the boundary pixel column. Updating the color component value of each pixel by multiplying the color component value of each pixel to be
The update means of the image processing device sets the APL in the second region and the average luminance value of the boundary pixel column among the luminance value correction coefficients set in advance for each different APL and each different luminance value. An update step of identifying a corresponding luminance value correction coefficient and multiplying the updated color component value of each pixel constituting the boundary pixel column by the specified luminance value correction coefficient;
The calculation means of the image processing apparatus is configured such that the APL in the second area is APL2, the total number of pixels in the second area is n, the number of pixels constituting the boundary pixel column is p, and the boundary pixels A step of calculating ΔS = (APL2 × n−Ave × p) / (n−p) where Ave is an average luminance value calculated from the color component values updated in the updating step of each pixel constituting the column. When,
Means for updating the color component value of each pixel by subtracting ΔS from the color component value of each pixel other than the boundary pixel column in the second region, wherein the means for updating the color component value of the image processing device An image processing method comprising:

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