JP2006330094A - Color image display device, color image display method, program and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device by which preferable color reproduction is realized by suppressing a phenomenon wherein a color in appearance of an important color seems different by an area effect of a color that lightness seems high when an area becomes large and on the contrary, lightness seems low when the area becomes small even in the case of the same color. <P>SOLUTION: This color image display device has: a storage means 32 for storing data for color display for one screen; an object color specification means 34 for specifying an object color whose the lightness is compensated; an object color area calculation means 42 for integrating the number of continuous pixels having the object color in the data for color display to calculate an object color area occupied by the continuous pixels having the object color; a lightness compensation means 46 for changing lightness data about the continuous pixels having the object color based on ratio of the object color area to the whole image area of one screen; and a display means 48 for performing the color display on the basis of the data for color display for one screen including data about the continuous pixels having the object color after changing the lightness data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a color image display device and a color image display method. For example, the present invention relates to a color image display device and a color image display method in which one pixel can be displayed in three primary colors and a color signal corresponding to a mixing ratio of the three primary colors is input and displayed.

  CRT, LCD (Liquid Crystal Display), PDP and the like are used as a device for color display, and RGB (red green blue) three primary colors are used as general basic colors.

  In such a display device, it is an important factor to faithfully reproduce the input image. Various methods have been proposed for correction to faithfully reproduce an input image. For example, Patent Document 1 discloses an invention that compensates for the color area effect.

  The color area effect is a phenomenon in which lightness appears to be different depending on the size of the area of the same color. According to the area effect of color, it is said that even if the area is the same color, the lightness looks high when the area is large, and conversely, the lightness appears low when the area is small. Patent Document 1 proposes a method for compensating for the area effect of color between an input image and an output image in an image processing apparatus that scales the input image and outputs the image after the scaling. Yes. By correcting the lightness value of the image data after scaling according to the magnification of the scaling, the same impression can be given to the user regarding the colors of the input image and the output image.

  FIG. 6 and FIG. 7 show the lightness correction procedure in the method disclosed in Patent Document 1. FIG. 8A shows an example of a document to be read. Here, a case where the document shown in FIG. 8A is read will be described. The brightness correction procedure according to the method of Patent Document 1 will be described with reference to FIGS.

  Assume a process in which a user sets color copy conditions in a color copier.

  When the “auto density” mode is selected, a “image quality monitor” key for instructing to output a monitor image is displayed on the touch panel. When the user presses this “image quality monitor” key, the CPU executes the image quality monitor mode process shown in FIG. 6 as follows.

  When the image quality monitor mode is selected (S601), first, the size of the document of FIG. 8A placed on the document glass is determined based on the output of the document size detection sensor (S602).

  Next, the currently selected paper size is determined (S603). In order to input the number of monitor images desired by the user, “Please select the number of images on the monitor” is displayed on the touch panel, and “AUTO (automatic)” is displayed on the magnification display section (S604). . Here, the reason for displaying “AUTO (automatic)” is that the magnification ratio is increased to 70% as the number of monitor images increases to 2, 4, and 8 in order to fit all the monitor images on one sheet. This is because it is gradually reduced to x50% and x35%.

  Next, the CPU calculates and sets a scaling factor according to the number of input monitor images (S605).

  Next, the CPU controls the brightness correction processing unit to perform the brightness correction process shown in FIG. 7 (S606). Specifically, as shown in FIG. 7, the brightness correction processing unit refers to the brightness correction table in accordance with the control of the CPU (S701), and the magnification of the monitor image (the magnification set in the process of S605) and The brightness value is corrected according to the brightness value of the input document image (S702).

  The lightness correction processing unit refers to the lightness correction table, performs correction to decrease the lightness value when the magnification is enlargement, and performs correction to increase the lightness value when the magnification is reduction. This is because, according to the color area effect, even if the area of the same color increases, the lightness looks high, and conversely, when the area becomes small, the lightness looks low, so this is compensated. Further, the brightness correction table is such that if the brightness value of the input document image is high, the correction amount with respect to the brightness value is increased. Conversely, if the brightness value of the input document image is low, the original image data The correction amount for the brightness value is set to be small. The reason for this is that if the input image has a high lightness value, such as skin color, the color area effect is large, and conversely if the input image has a low lightness value, the color area effect is small. This is to compensate for the difference in effect.

  The effect of the above brightness correction will be specifically described below using an example of monitor image output.

  FIG. 8B shows an example of monitor image output. FIG. 8A is an output example when 8 is specified as the number of monitor images for the input document in FIG. 8A. Here, the size of the output paper 130 in FIG. 8B is the input in FIG. 8A. Assume that the same size as the document size is specified and output. Here, it is assumed that the brightness value of the image 120 of the input document is V = 30.

  For the input document in FIG. 8A, as shown in FIG. 8B, eight monitor images 121 to 128 are arranged in one page in order of brightness. In FIG. 8B, the higher the lightness value, the denser the hatched density, and the lower the lightness value, the denser the hatched density.

Of the eight monitor images in FIG. 8B, the monitor image 124 is an image having the same brightness as the input document 120 in FIG. Since the input document of FIG. 8A and the output size of FIG. 8B are the same, the monitor image 124 is output with the image 120 reduced, so the brightness of the monitor image 124 is obtained by the brightness correction process described above. The value V ₀ is corrected to be brighter than the brightness value V of the image 120, and the brightness value is V ₀ = 35. However, due to the color area effect, the impression that the monitor image 124 gives to the user matches the impression that the input original image 120 gives to the user.

The brightness values of the monitor images 123, 122, and 121 that are brighter than the monitor image 124 are (V ₀ +2) = 37, (V ₀ +4) = 39, and (V ₀ +6) = 41, respectively. The brightness values of the monitor images 125, 126, 127, and 128 that are darker than the image 124 are (V ₀ -2) = 33, (V ₀ -4) = 31, (V ₀ -6) = 29, V ₀ −8) = 27.

In Patent Document 1, lightness correction is performed in the above-described procedure.
JP 2001-339602 A

  However, since the conventional brightness correction method described above does not consider the influence of the area of the entire display area, there is a problem that the brightness impression received by the user changes when the area of the entire display area changes.

  In the lightness correction method described in Patent Document 1, the lightness correction amount is determined only on the basis of the variable magnification, that is, the area of the original image and the area of the output image, and does not consider the area of the entire display region.

  However, even if the size of the image is the same, if the area of the entire display region changes, the impression of the brightness that the user receives from the image changes even if the image has the same brightness. FIG. 8C shows an example in which the same image as that shown in FIG. 8B is output to the output paper 131 having a size four times larger than the output paper 130 shown in FIG. 8B. A portion indicated by a broken line in FIG. 8C indicates a paper size range of the output paper 131.

  The monitor images 121 to 128 shown in FIG. 8C are exactly the same as the monitor images 121 to 128 shown in FIG. 8B, that is, output with the same brightness, but for example, monitors with the same brightness. Looking at the image 124, the user receives a darker impression in FIG. 8C than in FIG. 8B. This is because, even if both monitor images 124 are the same size, the area ratio of FIG. 8C with respect to the entire output sheet is smaller.

  In the brightness correction method described in Patent Document 1, both the monitor image is output on the output paper 130 of FIG. 8B and the output paper 131 of FIG. 8C having a larger size. 124 is also output with the same brightness, and as a result, the user receives the impression that the monitor images 124 of the same brightness have different brightness in FIGS. 8B and 8C. become.

  The present invention solves the above-described conventional problems, and provides a color image display device and a color image display method that reduce the uncomfortable feeling of color appearance due to the area effect in consideration of the influence of the area of the entire display region. It is intended to provide.

In order to solve the above-described problem, the first aspect of the present invention provides:
Storage means for storing color display data for one screen;
A target color specifying means for specifying a target color for correcting the brightness;
A target color area calculating means for calculating the target color area occupied by the continuous pixels having the target color by accumulating the number of continuous pixels having the target color in the color display data;
Based on the ratio of the target color area to the total image area occupied by the color display data for one screen, the continuous pixels having the target color are darker as the ratio is larger and brighter as the ratio is smaller. Brightness correction means for changing the brightness data of
A color image display device comprising: display means for performing color display based on color display data for one screen including data of continuous pixels having the target color after changing brightness data.

The second aspect of the present invention
Furthermore, the value of the ratio of the target color area to the total image area is grouped step by step for each predetermined width in the order of size, and a lightness correction magnification table in which a correction magnification indicating the degree of change in lightness is set for each group. With
The color image display according to the first aspect of the invention, wherein the brightness correction unit changes brightness data of continuous pixels having the target color using a correction magnification of a group to which the ratio belongs based on the brightness correction magnification table. Device.

The third aspect of the present invention
The lightness correction means does not change the lightness data of the continuous pixels having the target color when the ratio is a predetermined value, and darkens the lightness data when the ratio is larger than the predetermined value. In the color image display device according to the first aspect of the present invention, the brightness data is changed to be brighter when the brightness data is smaller than the predetermined value.

The fourth aspect of the present invention is
The target color specifying means is the color image display device according to the first aspect of the present invention, wherein the target color is specified by a combination of hue, saturation, and lightness.

The fifth aspect of the present invention provides
The color image display device according to the first aspect of the present invention, wherein the brightness correction means does not change the brightness data of the pixel of the target color when the accumulated number of consecutive pixels is less than a predetermined number. It is.

The sixth aspect of the present invention provides
The color image of the first aspect of the present invention, wherein the target color area calculation means integrates only pixels in which the number of consecutive pixels having the target color having the same X coordinate or Y coordinate is equal to or greater than a predetermined number of pixels. It is a display device.

The seventh aspect of the present invention
A storage step for storing color display data for one screen;
A target color specifying step for specifying a target color for correcting the brightness;
A target color area calculating step of calculating the target color area occupied by the continuous pixels having the target color by integrating the number of continuous pixels having the target color in the color display data;
Based on the ratio of the target color area to the total image area occupied by the color display data for one screen, the continuous pixels having the target color are darker as the ratio is larger and brighter as the ratio is smaller. A brightness correction step to change the brightness data of
A color image display method comprising: a display step of performing color display based on the color display data for one screen including data of continuous pixels having the target color after changing the brightness data.

In addition, the eighth aspect of the present invention
In the color image display method of the seventh aspect of the present invention, the storing step for storing color display data for one screen, the target color specifying step for specifying a target color for correcting the brightness, and continuous pixels having the target color The target color area calculating step for calculating the target color area occupied by the image, and the brightness of the continuous pixels having the target color based on the ratio of the target color area to the total image area occupied by the color display data for one screen The brightness correction step for changing data and the display step for color display based on color display data for one screen including data of continuous pixels having the target color after the brightness data is changed are executed. This is a program for causing a computer to function.

The ninth aspect of the present invention provides
A recording medium on which a program according to the eighth aspect of the present invention is recorded, and is a recording medium usable by a computer.

  According to the present invention, it is possible to provide a color image display device and a color image display method that reduce the uncomfortable feeling of color appearance due to the area effect in consideration of the influence of the area of the entire display region.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a configuration diagram of a display device 30 according to the first embodiment of the present invention.

  The display device 30 according to the first embodiment includes a writing unit 31, an image memory 32, a signal converting unit 33, a target color specifying unit 34, a target color frequency calculating unit 35, a target color frequency determining unit 36, a pixel signal extracting unit 38, X direction histogram creation means 39, solid image extraction means 40, target image position storage means 41, area calculation means 42, magnification calculation means 43, corrected brightness determination means 44, target image determination means 45, RGB signal correction means 46, reading means 47 and RGB display means 48.

  Hereinafter, the operation of each component of the display device 30 according to the first embodiment will be described.

  The writing unit 31 is a unit that records the RGB signals input in time series in the image memory 32. The image memory 32 is a memory that stores the input RGB signal at an address corresponding to the position of the screen, and records one frame image for color correction. An RGB signal can be written or read by designating an address.

  The signal conversion unit 33 is a unit that calculates and creates hue, saturation, and brightness signals from RGB signals.

  The target color specifying means 34 is a means for specifying the color of the target image to be corrected (hereinafter referred to as the target color) by a combination of hue, saturation, and brightness. Note that it is more practical to specify the combination of hue, saturation, and lightness specified here by giving each value a certain range.

  The target color frequency calculating means 35 is a means for calculating the frequency of the target color specified by the target color specifying means 34 for one frame image recorded in the image memory 32.

  The target color frequency determination unit 36 is a unit that determines whether the frequency of the target color calculated by the target color frequency calculation unit 35 is equal to or higher than a preset threshold value. When the frequency of the target color is equal to or higher than the threshold, the frequency determination signal notified to the pixel signal extraction unit 38 is set to 1 (True). Note that the threshold value in this case corresponds to an example of a predetermined number of the present invention. If the frequency of the target color is less than this threshold, it is determined that the area is a small area such as hatching, so that such a small area is not included in the target color area.

  The pixel signal extraction unit 38 is a unit that extracts a pixel having a target color from each pixel of an image of one frame when the frequency determination signal notified from the target color frequency determination unit 36 is 1 (True).

  The X direction histogram creation means 39 is a means for creating a frequency histogram for the X direction (or Y direction) of an image. This frequency histogram can be created by examining how many pixels having the target color are in the X direction line (or Y direction line).

  The solid image extraction unit 40 is a unit that extracts a pixel region having a continuous target color. Pixels with the same X-direction address value having the target color are extracted as a pixel area having the target color when the number of pixels is equal to or greater than a predetermined number. When there is a pixel area having the target color, the target image position storage unit 41 is notified by the solid image determination signal that “a solid image exists”.

  The target image position storage unit 41 stores a position on the screen where the target image having the target color exists when it is notified that a solid image exists by the solid image determination signal from the solid image extraction unit 40. It is.

  The area calculation means 42 is a means for calculating the area of the target image having the target color by accumulating the frequency of the pixels having the target color determined to be a solid image, obtained from the solid image extraction means 40. .

  The magnification calculating means 43 is a means for setting a correction magnification for changing the brightness of the target image.

  The corrected lightness determination unit 44 multiplies the lightness of the target color by the correction magnification set by the magnification calculator 43 to obtain the lightness of the target color after correction (hereinafter referred to as corrected lightness). Is a means for determining.

  The target image determination unit 45 is a unit that determines whether or not the position information of the target color given from the target image position storage unit 41 is equal to the reading address specified from the reading unit 47. When it is equal to the read address, the target image determination unit 45 determines that the pixel of the read address is a target color pixel, and sets the target image determination signal to the RGB signal correction unit 46 to 1 (True).

  The RGB signal correction unit 46 acquires the target image determination signal notified from the target image determination unit 45, the RGB signal read from the image memory 32 by the read address specified by the read unit 47, and the corrected lightness determination unit 44. This is means for creating an RGB signal 79 obtained by correcting the brightness data from the corrected brightness. The RGB signal correction means 46 changes the RGB signal read from the image memory 32 when the target image determination signal is 1 (True), and creates the RGB signal 79 so that the brightness data becomes the corrected brightness.

  The reading unit 47 is a unit that designates an address and extracts an RGB signal recorded in the image memory 32. The RGB signals read from the image memory 32 are input to the reading means 47 through the RGB signal correcting means 46. The reading unit 47 is also a unit that creates and outputs a synchronization signal and an RGB signal in accordance with a format for displaying an image on the RGB display unit 48 from the RGB signal input through the RGB signal correction unit 46. .

  The RGB display means 48 is a means for displaying an image from the synchronization signal and the RGB signal input from the reading means 47.

  The display device 30 corresponds to an example of the color image display device of the present invention. The image memory 32 corresponds to an example of the storage unit of the present invention. A combination of the target color frequency calculation means 35, the target color frequency determination means 36, the pixel signal extraction means 38, the X-direction histogram creation means 39, the solid image extraction means 40, and the area calculation means 42 is a target color of the present invention. This is an example of the area calculating means. A combination of the magnification calculation means 43, the corrected lightness determination means 44, and the RGB signal correction means 46 is an example of the lightness correction means of the present invention. A combination of the reading means 47 and the RGB display means 48 is an example of the display means of the present invention.

  Next, an operation for correcting the brightness in the display device 30 of the first embodiment will be described.

  FIG. 2 shows an example of a display screen on which brightness correction is desired in the first embodiment. The entire display area 11 is an entire area that can be displayed on the screen, and the portion of the target image 10 indicates a color area for which brightness correction is performed.

  FIG. 3 shows the lightness correction procedure of the first embodiment.

  First, the target color to be corrected is specified by the target color specifying means 34 (S301). Here, the color of the portion of the target image 10 in FIG. 2 is designated as the target color. The target image 10 is designated by setting the hue, saturation, and brightness of the target color. Note that the processing of S301 corresponds to an example of the target color designation step of the present invention.

  Next, the writing unit 31 records the RGB signals input in time series in the image memory 32. The processing for storing the RGB signals in the image memory 32 corresponds to an example of the storage step of the present invention.

  Next, the target color frequency calculation means 35 extracts the frequency of the target image 10 having the target color for a certain whole image (here, the entire display area 11) to be subjected to color correction (S302).

  Here, when the target color frequency determination unit 36 determines that the frequency of the target color is larger than a predetermined threshold (S303), the X-direction histogram creation unit 39 extracts the pixel signal using the pixel signal extraction unit 38. A frequency histogram for the X direction (or Y direction) of the image of the region having the target color, that is, the target image 10 is created from the pixels having the target color (S304).

  An example of the frequency histogram of the target color in the entire display area 11 is shown below the entire display area 11 in FIG. 2, and the X-direction histogram creating means 39 creates such a frequency histogram. In the case of FIG. 2, since the region having the target color in the entire display region 11 is only the portion of the target image 10, the frequency histogram is a histogram as shown in FIG. 2.

  Then, the solid image extraction unit 40 extracts a solid image region from the target image 10 from the frequency histogram created by the X direction histogram creation unit 39 (S305).

The solid image is extracted using the frequency of the target color pixel at each address in the X direction. FIG. 4 shows an example of the frequency of pixels having a target color for addresses in the X direction. Using the frequency histogram of FIG. 4, a region where the frequency is equal to or higher than a predetermined threshold and is continuous for a predetermined number of pixels is determined as a solid portion, and the other regions are not solid portions (non-solid portion). Is determined. In the case of FIG. 4, the range of X _{0 to} X _{1 in} which the frequency of the target color exceeds a predetermined threshold is determined as a solid part, and the other is determined as a non-solid part. Note that the threshold value in this case corresponds to an example of the predetermined number of pixels of the present invention.

  Next, the area calculation means 42 calculates the area of the solid area in the target image 10 (S306). The area of the solid area is obtained by accumulating the frequency of pixels having the target color of the solid area. Here, as shown in FIG. 2, since the region of the target image 10 having the target color is one region, the region of the target image 10 itself is determined to be a solid image region, and thus the area of the target image 10 is calculated. Will be.

  Note that the processing of S304 to S306 corresponds to an example of a target color area calculation step of the present invention.

  Next, the magnification calculation means 43 sets the correction magnification for changing the brightness of the target color using the area of the target image 10 obtained here (S307), and the corrected brightness determination means 44 sets the correction magnification. New brightness data (corrected brightness) is determined by multiplying the brightness data of the target color (S308).

  In the process of S303, when it is determined that the frequency of the target color is equal to or less than a predetermined threshold, the above-described correction lightness determination process (S304 to S308) is not performed.

  The correction magnification set in the process of S307 is given by, for example, Equation 1 using the coefficient A, the area of the target image 10, and the area of the entire image (area of the entire display area 11).

数１において、例えば、対象画像面積が全画像面積の１／４のときに明度の変更をせず、対象画像面積が全画像面積の１／４より大きいときに明度を下げ、小さいときに明度を上げたいとした場合には、係数Ａ＝２とすればよい。

In Equation 1, for example, the brightness is not changed when the target image area is 1/4 of the total image area, the brightness is decreased when the target image area is greater than 1/4 of the total image area, and the brightness is decreased when the target image area is small. If it is desired to increase the coefficient, the coefficient A = 2 may be set.

  FIG. 5A shows the relationship between the correction magnification, the target image area, and the total image area expressed by Equation 1 when the coefficient A = 2.

  In this case, for example, when the target image area / total image area = 1/4, the correction magnification is 1 from Equation 1. For example, when the target image area / total image area = 1/16, the correction magnification is 2, and the brightness can be increased. When the target image area / total image area = 1, the correction magnification is The brightness can be lowered to 0.5.

  In this case, the value of the area ratio (target image area / total image area) of ¼ that does not change the brightness corresponds to an example of a predetermined predetermined value of the present invention.

  Then, the target image determination unit 45 determines whether or not the position information of the target image 10 given from the target image position storage unit 41 is equal to the reading address specified by the reading unit 47. Is notified to the RGB signal correcting means 46 as 1 (True).

  The RGB signal correction unit 46 creates an RGB signal to be input to the reading unit 47 from the target image determination signal, the RGB signal read from the image memory 32, and the corrected brightness 75 acquired from the corrected brightness determination unit 44. When the target image determination signal is 1 (True), the RGB signal correction means 46 changes the RGB signal read from the image memory 32 and creates an RGB signal using the brightness data as corrected brightness data.

  Note that the processing of S307 and S308 and the processing in which the RGB signal correcting means 46 generates the RGB signal having the corrected brightness data are an example of the brightness correction step of the present invention.

  Reading means 47 designates a reading address and takes out an RGB signal recorded in the image memory 32. The RGB signal extracted from the image memory 32 is input to the reading unit 47 through the RGB signal correcting unit 46. The reading means 47 creates a synchronization signal and an RGB signal to be displayed by the RGB display means 48 from the input RGB signals, and inputs them to the RGB display means 48.

  The RGB display unit 48 displays an image from the synchronization signal and the RGB signal input from the reading unit 47. The process in which the RGB display means 48 displays a video corresponds to an example of the display step of the present invention.

  If it is determined in step S303 that the target color frequency determination unit 36 determines that there is no target color area, that is, if the frequency determination signal is not 1 (True), as shown in FIG. 39, the solid image extraction means 40, the target image position storage means 41, the area calculation means 42, the magnification calculation means 43, and the corrected brightness determination means 44 need not be processed, and the brightness change need not be performed.

  In the first embodiment, the target color designating unit 34 designates the target color by a combination of hue, saturation, and lightness in the process of S301. However, the target color is not necessarily designated by a combination of these three elements. The target color may be specified by any one of these three elements or a combination of two elements.

  In the first embodiment, the processing for obtaining the correction magnification by the magnification calculator 43 is calculated using Equation 1, but the correction magnification associated with the ratio of the target image area to the total image area is provided. A brightness correction magnification table may be provided, and the correction magnification may be determined using the brightness correction magnification table.

  FIG. 5B shows an example of the area ratio (target image area / total image area) set in the brightness correction magnification table and the correction magnification associated therewith when the brightness correction magnification table is used. In this way, by using the brightness correction magnification table in which the area ratio is grouped for each predetermined width and the correction magnification is set for each group, the correction magnification can be obtained from the area ratio.

  It should be noted that the calculation formula of the correction magnification used by the magnification calculation means 43, its coefficient, and the brightness correction magnification table are adapted to the characteristics of each display so that appropriate brightness correction is performed according to the characteristics of the display to be displayed. Try to use what you have.

  As described above, by using the color image display device or the color image display method of the present invention, even if the area of the entire display area changes, the user does not feel a sense of discomfort in the color appearance due to the area effect. Can be displayed.

  For example, even when the total image areas (130 and 131) are different as in FIGS. 8B and 8C, the image 124 in FIG. 8B and the image 124 in FIG. 8C have the same brightness. As can be seen, the brightness of the image 124 in FIG. 8C can be made lower than the brightness of the image 124 in FIG. 8B so that the user feels the same brightness.

  Further, in the related art disclosed in Patent Document 1, brightness cannot be corrected unless the system “scales an input image and outputs the image after scaling”. For example, it has not been possible to deal with a case where a target image having a certain color is displayed multiple times on the display display while changing the area without changing the color. The color image display device or the color image display method of the present invention can be applied to such a case, and even when an image is displayed a plurality of times while changing the area without changing the color, the image of the image is displayed to the user. It can be displayed without giving the impression that the brightness changes.

  As described above, when the color image display apparatus or the color image display method of the present invention is used, even if the area is the same, the brightness increases when the area increases, and conversely, the phenomenon that the brightness decreases when the area decreases (area effect) is canceled. And faithful color transmission becomes possible.

  Note that the program of the present invention includes all or part of the operations of the storage step, the target color designation step, the target color area calculation step, the brightness correction step, and the display step of the color image display method of the present invention described above. A program that is executed by a computer and that operates in cooperation with the computer.

  The recording medium of the present invention is an operation of all or part of the storage step, target color specifying step, target color area calculating step, lightness correction step, and display step of the color image display method of the present invention described above. Is a recording medium that records a program for causing the computer to execute the program, and is a recording medium that can be read by the computer and that is used in cooperation with the computer.

  The “partial steps” of the present invention mean one or several steps out of the plurality of steps.

  Further, one usage form of the program of the present invention may be an aspect in which the program is recorded on a computer-readable recording medium and operates in cooperation with the computer.

  Further, the recording medium includes a ROM and the like.

  The computer of the present invention described above is not limited to pure hardware such as a CPU, and may include firmware, an OS, and peripheral devices.

  As described above, the configuration of the present invention may be realized by software or hardware.

  The color image display device and the color image display method according to the present invention have an effect of reducing the uncomfortable feeling of the color appearance due to the area effect in consideration of the influence of the area of the entire display region, and the mixing of the three primary colors. This is useful as a color image display device and a color image display method for inputting and displaying a color signal corresponding to the ratio.

The block diagram which shows the structure of the display apparatus of Embodiment 1 of this invention. The figure which shows the example of the display screen which wants to perform brightness correction in Embodiment 1 of this invention The figure which shows the correction | amendment procedure of the brightness of Embodiment 1 of this invention. The figure explaining the method to extract the solid image in Embodiment 1 of this invention (A) The figure which showed an example of the relationship between the correction magnification and area ratio (target image area / total image area) in Embodiment 1 of this invention, (b) The lightness correction magnification in Embodiment 1 of this invention The figure which showed an example of the relationship between the correction magnification set to a table, and an area ratio (target image area / total image area) The figure which shows the process sequence of the image quality monitor mode at the time of correcting the conventional brightness The figure which shows the process sequence of the brightness correction process part at the time of correct | amending the conventional brightness. (A) A diagram showing an example of a document to be read, (b) a diagram showing an example of output of a monitor image, and (c) a diagram showing an example of outputting a monitor image on paper of different sizes

Explanation of symbols

DESCRIPTION OF SYMBOLS 30 Display apparatus 31 Writing means 32 Image memory 33 Signal conversion means 34 Target color designation means 35 Target color frequency calculation means 36 Target color frequency determination means 38 Pixel signal extraction means 39 X direction histogram creation means 40 Solid image extraction means 41 Target image position Storage means 42 Area calculation means 43 Magnification calculation means 44 Correction lightness determination means 45 Target image determination means 46 RGB signal correction means 47 Reading means 48 RGB display means

Claims (9)

Storage means for storing color display data for one screen;
A target color specifying means for specifying a target color for correcting the brightness;
A target color area calculating means for calculating the target color area occupied by the continuous pixels having the target color by accumulating the number of continuous pixels having the target color in the color display data;
Based on the ratio of the target color area to the total image area occupied by the color display data for one screen, the continuous pixels having the target color are darker as the ratio is larger and brighter as the ratio is smaller. Brightness correction means for changing the brightness data of
A color image display device comprising: display means for performing color display on the basis of the color display data for one screen including data of continuous pixels having the target color after changing the brightness data. Furthermore, the value of the ratio of the target color area to the total image area is grouped step by step for each predetermined width in the order of size, and a lightness correction magnification table in which a correction magnification indicating the degree of change in lightness is set for each group. With
2. The color image display according to claim 1, wherein the brightness correction unit changes brightness data of continuous pixels having the target color using a correction magnification of a group to which the ratio belongs based on the brightness correction magnification table. apparatus.   The lightness correction means does not change the lightness data of the continuous pixels having the target color when the ratio is a predetermined value, and darkens the lightness data when the ratio is larger than the predetermined value. The color image display device according to claim 1, wherein the brightness data is changed to be brighter when the brightness data is smaller than the predetermined value.   The color image display device according to claim 1, wherein the target color designating unit designates the target color by a combination of hue, saturation, and brightness.   2. The color image display device according to claim 1, wherein when the number of accumulated continuous pixels is less than a predetermined number, the brightness correction unit does not change the brightness data of the pixels of the target color. .   2. The color image according to claim 1, wherein the target color area calculation unit integrates only pixels in which the number of consecutive pixels having the target color having the same X coordinate or Y coordinate is equal to or greater than a predetermined number of pixels. Display device. A storage step for storing color display data for one screen;
A target color specifying step for specifying a target color for correcting the brightness;
A target color area calculating step of calculating the target color area occupied by the continuous pixels having the target color by integrating the number of continuous pixels having the target color in the color display data;
Based on the ratio of the target color area to the total image area occupied by the color display data for one screen, the continuous pixels having the target color are darker as the ratio is larger and brighter as the ratio is smaller. A brightness correction step to change the brightness data of
A color image display method comprising: a display step of performing color display based on color display data for one screen including data of continuous pixels having the target color after changing the brightness data.   The color image display method according to claim 7, wherein the storing step for storing color display data for one screen, the target color specifying step for specifying a target color for correcting brightness, and a continuous pixel having the target color The target color area calculating step for calculating the target color area occupied by the image, and the brightness of the continuous pixels having the target color based on the ratio of the target color area to the total image area occupied by the color display data for one screen The brightness correction step for changing data and the display step for color display based on color display data for one screen including data of continuous pixels having the target color after the brightness data is changed are executed. Program to make the computer function for the purpose. A recording medium on which the program according to claim 8 is recorded, the recording medium being usable by a computer.

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