JP5337498B2 - Color correction processing apparatus, color correction processing method, color correction processing program, and computer-readable medium storing the program - Google Patents

Description

  The present invention relates to a color correction processing apparatus that performs predetermined color correction on color image data, a color correction processing method, a color correction processing program, and a computer-readable medium storing the program. More specifically, the present invention relates to a color correction processing apparatus, a color correction processing method, a color correction processing program, and a computer-readable medium storing the program for performing color correction so that a color blind person can accurately recognize colors.

  “Color blindness” means that color recognition and identification cannot be performed correctly due to the lack or incompleteness of color-sensitive pyramidal cells present in the retina of the eye. This color vision disorder is classified into type 1 to type 3 depending on the type of cone cell having the disorder. Hereinafter, the contents of these failures will be described in order.

  Type 1 shows a color blindness that is difficult to recognize red mainly due to a failure of L cone cells that recognize red. Type 2 shows a color blindness that is difficult to recognize green mainly due to a failure of M cone cells that recognize green. Type 1 and type 2 account for the largest number of color blindness, and as of January 2009, it is said that in Japan, it corresponds to 1 in 20 males and 1 in 500 females.

  Type 3 color blindness is mainly caused by S pyramidal cells recognizing blue, but it is rare that this disorder occurs congenitally and does not feel much inconvenience in daily life.

  People with these color vision impairments (hereinafter referred to as “color vision impaired people”) appear to have the same specific color, and when these colors are adjacent, it becomes difficult to distinguish them. For example, in the case of type 1 and type 2 color blind people, if red and green are adjacent, they will be confused. For this reason, it may be difficult to distinguish between green leaves and autumn leaves, calendar weekdays and holidays, meat burnt portions and raw portions, and the like, which may hinder life. Furthermore, it is difficult for type 1 color blind persons to distinguish between dark red and black, and changes in saturation with respect to red cannot be normally identified.

As a means for solving the above-mentioned inconveniences for color blind persons, there is a technique disclosed in Patent Document 1. In this technique, a grayscale image having a color that is difficult to distinguish is created, and the image and the original image are alternately displayed in flash so that these colors can be identified.
Patent No. 4097628

  However, in the technique of Patent Document 1, an original image, a grayscale image, and a light gradation image are alternately displayed, so that the image becomes very unnatural. In addition, the mixed colors of red and green that are difficult to recognize for type 1 and type 2 color blind persons are easy to distinguish, but other colors, for example, the boundary between red and black, are difficult to distinguish. In addition, the technology only deals with hue, and does not consider other color elements such as brightness and saturation. Therefore, it cannot be said that the above-mentioned inconvenience is completely solved.

  The present invention was devised in view of the above circumstances, and an object of the present invention is to provide a color image to make it easier for color blind persons of type 1 and type 2 to distinguish between red, green, and their mixed colors. To provide a color correction processing apparatus, a color correction processing method, a color correction processing program, and a computer readable medium storing the program for performing predetermined color correction.

  Another object of the present invention is to provide a color correction processing device, a color correction processing method, a color correction processing program, and a computer-readable computer storing the program for facilitating recognition of red saturation by a type 1 color blind person. To provide a medium.

The invention of claim 1 devised to solve the above-mentioned problems is a color correction processing device that performs predetermined color correction on color image data, and is a pixel constituting the color image data, and its R level. The brightness of the red part composed of pixels with a greater than G level and the brightness of the green part composed of pixels constituting the color image data with the G level greater than the R level are different from each other. The color correction processing apparatus is characterized in that the color correction processing apparatus is changed with a period.

The invention of claim 2 which is made to solve the above problems, the color correction processing apparatus according to claim 1, brightness of the red portion and the green part is varied within the variation range, their variation range , respectively, and wherein the Rukoto is changed according to the hue of the red portion and the green portion.

Invention of Claim 3 created in order to solve the said subject WHEREIN: The color correction processing apparatus of Claim 1 or 2 WHEREIN : The brightness of the said red part and the said green part changes within a change range, Those variation range, respectively, and wherein the Rukoto is changed according to the saturation of the red portion and the green portion.

Invention of Claim 4 created in order to solve the said subject is a color correction processing apparatus as described in any one of Claim 1 thru | or 3. WHEREIN: The brightness of the said red part and the said green part is a different period, respectively. It is characterized by changing in stages.

Invention of Claim 5 created in order to solve the said subject WHEREIN: The color correction processing apparatus of Claim 4 WHEREIN: The brightness of the said red part and the said green part changes in two steps with a respectively different period. It is characterized by.

The invention of claim 6 devised to solve the above-mentioned problem is a color correction processing method for performing color correction on color image data, and for each of the pixels constituting the color image data , its R level and G comparing the level of the pixel is larger R level red portion, a color identifying step of identifying the pixels larger G level as a green part, the brightness of the brightness and the green portion of the red portion of the above identified The color correction processing method includes: a brightness change step for changing the values at different periods.

Invention of Claim 7 created in order to solve the said subject WHEREIN: The color correction processing method of Claim 6 WHEREIN : The brightness of the said red part and the said green part changes within the change range, and those change range , respectively, and wherein the Rukoto is changed according to the hue of the red portion and the green portion.

Invention of Claim 8 created in order to solve the said subject is the color correction processing method of Claim 6 or 7 , The brightness of the said red part and the said green part changes within the change range, Those variation range, respectively, and wherein the Rukoto is changed according to the saturation of the red portion and the green portion.

Invention of Claim 9 created in order to solve the said subject WHEREIN: The color correction processing method of Claim 6 thru | or 8 WHEREIN: The brightness of the said red part and the said green part is a different period in the said brightness change step, respectively. It is characterized by being changed in stages.

Invention of Claim 10 created in order to solve the said subject WHEREIN: In the color correction processing method of Claim 9 , changing the lightness of the said red part and the said green part in two steps with a respectively different period. Features.

The invention of claim 11 created to solve the above problem is a program that causes a computer to execute the color correction processing method according to any one of claims 6 to 10 .

Invention of Claim 12 created in order to solve the said subject is a computer-readable medium which stored the program of Claim 11 .

A thirteenth aspect of the invention, which was created to solve the above problem, is an electronic circuit that performs the color correction processing method according to any one of the sixth to tenth aspects.

The invention of claim 14 , which was created to solve the above-mentioned problems, is a display device storing the electronic circuit according to claim 13 .

Colors that are difficult to recognize by type 1 and type 2 color blind persons are red, green, and mixed colors thereof. Therefore, in the first and sixth aspects of the invention, the red portion and the green portion in the original color image are selectively corrected. If the type 1 and type 2 color blind persons know the correction conditions in advance, they can accurately grasp the color situation in the image according to the change in brightness. Further, by performing color correction in units of pixels of the original color image, detailed and highly accurate color correction is provided.

In the second and seventh aspects of the invention, for example, in the red portion, as the R level is higher than the G level, that is, as the hue approaches red, the amount of change in brightness increases. On the other hand, in the green portion, the amount of change in brightness increases as the hue approaches green. Therefore, the type 1 and type 2 color blind persons can recognize the difference in hue between the red part and the green part in the image based on the degree of change in brightness. That is, by changing the “lightness” that is an attribute relating to color, it is possible to recognize the difference in “hue” of other attributes.

In the inventions of claims 3 and 8 , the lightness of the red portion and the green portion changes according to the saturation. Therefore, the type 1 and type 2 color blind persons can recognize the difference in color saturation based on the degree of change in lightness. That is, by changing the “brightness” that is an attribute relating to the color, the difference in “saturation” of other attributes can also be recognized.

In the inventions according to claims 4 and 9 , the brightness of the red part and the green part is changed stepwise. As the number of steps increases, the brightness changes gradually, so it looks more natural. On the other hand, if the number of steps is reduced, the amount of data to be calculated is reduced and the load on the apparatus is reduced. Therefore, it is preferable to set the number of stages of lightness change in consideration of the aspect of lightness change and the load on the apparatus.

In the invention of claim 5 and claim 10 , the brightness of the red part and the green part is changed in two steps. Therefore, the present invention can be implemented with a processing apparatus with a low load on the apparatus and a low computing capacity.

The invention of claim 11 through claim 14 provides a color correction of the present invention programs are a computer readable medium, an electronic circuit, in the form of a display device.

  According to the present invention, a color correction processing device, a color correction processing method, a color correction processing program, and the program for facilitating identification of red, green, and their confusion colors by persons with type 1 and type 2 color blindness are stored. A computer readable medium can be provided. Furthermore, a color correction processing device, a color correction processing method, a color correction processing program, and a computer-readable medium storing the program for facilitating recognition of red saturation by a type 1 color blind person are also provided. It becomes possible.

A color correction processing apparatus according to an embodiment of the present invention is an apparatus that performs color correction on an original color image so that persons with type 1 and type 2 color blindness can recognize colors appropriately. A specific correction method changes the lightness of the red and green portions, which are difficult for the type 1 and type 2 color blind persons to recognize, at different periods. The period can be set to an arbitrary value, but the difference can be recognized more suitably as the difference between the periods is larger. In the present embodiment, the brightness switching period for the red part is set to 0.5 seconds, and the brightness switching period for the green part is set to 0.1 seconds.
Hereinafter, functions of a color correction processing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a functional block diagram of a color correction processing apparatus 1000 according to an embodiment of the present invention. When original color image data in a predetermined digital format is input to the color correction processing apparatus 1000, color image data subjected to color correction is output. The color correction processing apparatus 1000 includes a color processing unit 10, a frame image generation / storage unit 20, and an image output unit 30 as functional elements. Hereinafter, each functional element will be described in detail.

[Color processing section]
The color processing unit 10 has a function of performing calculation related to color correction of the original color image in units of pixels, and includes an R / G level comparison unit 110 and a lightness calculation unit 120.

  When receiving the data of the original color image (for example, the image shown in FIG. 2A), the R / G level comparison unit 110 obtains the color (R, G, B) level in each pixel constituting the image, Among them, the R level and the G level are compared. Here, the level of each color component is represented by a numerical value of a predetermined bit. For example, when it is expressed by 8 bits, it is a numerical value in the range of 0 to 255. Therefore, the R / G level comparison unit 110 compares these numerical values (levels) in the R component and the G component. As a result of the comparison, if the level of the R component is higher, the pixel is set as a red part pixel (hereinafter referred to as an R system pixel), and a pixel having a higher G component level is set as a green part pixel (hereinafter referred to as the R part pixel). , G pixels).

  In parallel with the above-described processing, the lightness calculation unit 120 calculates a lightness increase / decrease rate d in each pixel of the original color image. The lightness increase / decrease rate d is a constant indicating how much the lightness of the color is changed, that is, how dark and bright the color is, and is obtained by the following equation.

式中、ｄは明度増減率、Ｒｉｎは元色彩画像の所定の画素におけるＲレベル、ＧｉｎはＧレベルである。
また、ｋは調整用変数である。人間の視感覚には個人差があり、また、元画像の色彩状況や、赤色および緑色部分の変化周期によっても見え方は変化する。したがって、ｋを用いてｄを可変して最適化する。ｋの値は特に限定するものではなく任意に設定してよいが、本発明者等はｋを０．１〜１．０の範囲の任意の値に設定すればｄを最適化できることを実験より確認している。

In the equation, d is a brightness increase / decrease rate, Rin is an R level in a predetermined pixel of the original color image, and Gin is a G level.
K is an adjustment variable. There are individual differences in human visual sensation, and the appearance changes depending on the color condition of the original image and the change cycle of the red and green portions. Therefore, optimization is performed by varying d using k. The value of k is not particularly limited and may be arbitrarily set. However, the present inventors have shown from experiments that d can be optimized by setting k to an arbitrary value in the range of 0.1 to 1.0. I have confirmed.

  Next, using the brightness increase / decrease rate d obtained by Expression (1), the amount of change in brightness (change range) in each pixel is obtained from Expressions (2) and (3) below.

Rco_upはＲレベルの明度の変化範囲内における最明値（以下、「最高明度値」とする）、Gco_upはＧレベルの最高明度値、Bco_upはＢレベルの最高明度値である。さらに、

Rco_up is the maximum brightness value (hereinafter referred to as “maximum brightness value”) within the brightness change range of the R level, Gco_up is the maximum brightness value of the G level, and Bco_up is the maximum brightness value of the B level. further,

Rco_downはＲレベルの明度の変化範囲内における最暗値（以下、「最低明度値」とする）、Gco_downはＧレベルの最低明度値、Bco_downはＢレベルの最低明度値である。

Rco_down is the darkest value (hereinafter referred to as “minimum brightness value”) within the brightness change range of the R level, Gco_down is the lowest brightness value of the G level, and Bco_down is the lowest brightness value of the B level.

  From the above equations (2) and (3), the brightness of the R, G, and B components in each pixel is set to change at the same rate. Further, the greater the lightness increase / decrease rate d, in other words, the greater the difference between the R level and the G level, that is, the closer the hue is to red or green, the greater the degree of change in lightness. On the other hand, when the lightness increase / decrease rate d is 0, that is, when the R level and the G level are the same (hue is yellow), the lightness does not change.

  When the lightness calculation unit 120 obtains the maximum lightness value and the minimum lightness value in all the pixels, the attribute of each pixel obtained by the R / G level comparison unit 110, that is, whether it is an R system pixel or a G system pixel. The result is added and sent to the frame image generation / storage unit 20.

[Frame image generation / storage unit]
The frame image generation / storage unit 20 has a function of generating a plurality (four in this embodiment) of frame images based on the calculation result of the lightness calculation unit 120. The first frame image generation unit 210, A two-frame image generation unit 220, a third frame image generation unit 230, and a fourth frame image generation unit 240 are provided.

  The first frame image generation unit 210 converts the first frame image (converted so that the lightness in the R and G pixels set by the R / G level comparison unit 110 is the maximum lightness value obtained by Expression (2)). For example, the image shown in FIG. Further, the second frame image generation unit 220 converts the brightness of the R-system pixel into the maximum brightness value, and further converts the brightness of the G-system pixel into the minimum brightness value (for example, the image shown in FIG. 2C). ), And the third frame image generation unit 230 converts the lightness of the R-system pixel into the minimum lightness value and the lightness of the G-system pixel into the maximum lightness value (for example, as shown in FIG. 2D). The fourth frame image generation unit 240 generates a fourth frame image (FIG. 2E) obtained by converting the lightness in the R system and G system pixels to be the minimum lightness value.

When the first to fourth frame images are generated, the frame image generation / storage unit 20 stores these frame images in a buffer (not shown) constituted by a memory, a hard disk, and the like.
In order to more clearly show the effect of this color correction, please refer to the color original image diagram of FIG. 2 attached as a reference color drawing to the property submission file submitted at the same time as the present application.

[Image output section]
The image output unit 30 has a function of selectively reading out and outputting the first to fourth frame images stored in the buffer, and includes a frame image selection unit 310. The frame image selection unit 310 outputs the output timing of each frame image based on a preset brightness change period of the red portion and the green portion (in this embodiment, red is 0.5 seconds and green is 0.1 seconds). To decide. FIG. 3 shows an example of the time chart. Frame types I to IV in the figure correspond to first to fourth frame images, respectively.

  Using the functions of the color processing unit 10, the frame image generation / storage unit 20, and the image output unit 30, the color correction processing apparatus 1000 performs the above-described color correction on the input original color image, and performs the first and second types. A color image that can be easily identified by a color blind person is output.

It should be noted that the amount of change (change range) in lightness of the red and green portions of the output color image is determined according to the degree of saturation. More specifically, between the pixels having the same hue in the original color image (between pixels having the same R level and G level), the increase / decrease rate d obtained by the above equation (1) is the same value. Therefore, the amount of change in the brightness of these pixels depends only on the values of Rin, Gin, and Bin with reference to equations (2) and (3). On the other hand, since the saturation increases as the R, G, and B levels increase, as a result, the amount of change in lightness increases as the saturation increases in pixels having the same hue.
For example, when d = 0.2, and the amount of change in brightness of two pixels where Rin is 30 and 200, respectively,
When Rin = 30, Rco_up = 36, Rco_down = 24, and the brightness change amount = 12.
When Rin = 200, Rco_up = 240 and Rco_down = 160, and the brightness change amount = 80.
Therefore, even if the pixels have the same hue, the degree of saturation difference can be indicated by the magnitude of the change in brightness.

  The color correction processing apparatus 1000 described above can be applied to various uses. For example, the color correction processing apparatus 1000 can be applied to a terminal having an imaging device (a mobile phone with a camera, a computer to which a camera is connected, etc.). In this case, the landscape captured by the imaging device is color-corrected by the color correction processing device 1000, and the corrected landscape is displayed on the monitor of the terminal. Therefore, the color blind person can know the color of the scenery by taking an image of the scenery that the user wants to know the color and observing the taken image on the monitor.

  In this embodiment, the brightness of the pixel of the color image is changed in two stages. However, the brightness change method of the present invention is not limited to this method. Alternatively, one or more intermediate values may be obtained, and the brightness may be changed in three or more stages. As the number of steps increases, the number of frame images to be created increases and the amount of data to be processed increases, but the brightness seems to change more naturally. For example, when the original image is a still image, many brightness change steps are set so that the change in brightness looks more natural, and in the case of a moving image, color correction processing is performed in real time following the frame rate. The brightness change step can be set as few as possible. That is, it is preferable that the number of steps of changing the brightness is appropriately determined based on the type of the original color image for performing color correction, the computing ability of the apparatus for performing the correction process, the visual sensation of the user who is color blind, .

  Furthermore, the present invention can be applied to various display devices such as an electric bulletin board and a liquid crystal bulletin board. In this case, it is preferable to switch between normal display and color-corrected display at a predetermined interval. As a result, it is possible to observe the contents displayed by both the color vision normal person and the color blind person at the same time.

  The function of the color correction processing apparatus according to the embodiment of the present invention has been described above. Next, the procedure of color correction processing performed by this color correction processing apparatus will be described with reference to the flowcharts of FIGS.

  Referring to FIG. 4 for the first time, original color image data as shown in FIG. 2A, which is a processing target, is input to the color processing unit 10 of the color correction processing apparatus 1000 (step S10). Next, a pixel to be processed is determined from the pixels constituting the image (step S20). When the pixel to be processed is determined, the R / G level comparison unit 110 compares the R level and the G level in the pixel (step S30). If the R level is greater than the G level (“YES” in step S30), the corresponding pixel is determined as an R system pixel (step S40). On the other hand, if the G level is greater than the R level (“NO” in step S30), the corresponding pixel is determined as a G-system pixel (step S50).

  The following processing is performed in parallel with the processing in steps S30 to S50. The lightness calculation unit 120 calculates the lightness increase / decrease rate d using the expression (1) for the pixel to be processed (step S60). Subsequently, the brightness change amount (maximum brightness value Rco_up and minimum brightness value Rco_down) is obtained using the brightness increase / decrease rate d and equations (2) and (3) (step S70).

  When the processes of steps S40, S50, and S70 are completed, the pixel attributes (R system and G system) and the brightness change amount, which are the results obtained by these processes, are associated with the coordinates of this pixel. If unprocessed pixels remain (“NO” in step S90), the processes in steps S20 to S80 are repeated for the unprocessed pixels. If all pixels have been processed (“YES” in step S90), all the data associated in the process of step S80 is passed to the frame image generation / storage unit 20.

  Next, a description will be given with reference to FIG. The frame image generation / storage unit 20 generates first to fourth frame images based on the received data. Specifically, the first frame image generation unit 210 converts the R, G, and B brightness of the original color image R and G pixels to the maximum brightness value Rco_up obtained in step S70 (step S100). This image is written in the buffer as a first frame image (step S110).

  Further, the second frame image generation unit 220 sets the R, G, and B lightness of the R pixel of the original color image to the maximum lightness value Rco_up obtained in step S70, and further the R, G, and B lightness of the G pixel. The minimum brightness value Rco_down obtained in step S70 is converted (step S120). This image is written in the buffer as a second frame image (step S130).

  Further, the third frame image generating unit 230 sets the R, G, and B brightness of the original color image to the minimum brightness value Rco_down, and further sets the R, G, and B brightness of the G pixel to the maximum brightness value Rco_up. Conversion is performed (step S140). This image is written in the buffer as a third frame image (step S150).

  Further, the fourth frame image generation unit 240 converts the R, G, and B brightness of the R color pixel and the G color pixel of the original color image into the minimum brightness value Rco_down (step S160), and this image is used as the fourth frame image. Write to the buffer (step S170).

When all the frame images are written in the buffer, the image output unit 30 next, based on the predetermined change period of the red part (0.5 seconds) and the change period of the green part (0.1 seconds), A time chart as shown in FIG. 3 is generated, and a frame image to be output is determined (step S180). Then, the determined frame image is read from the buffer (step S190) and output (step S200).
The above is the procedure of the color correction method according to the present embodiment. This method can provide color-corrected color images for type 1 and type 2 color blind persons.

  Note that the functions of the color correction processing apparatus according to an embodiment of the present invention are not limited to specific hardware resources or software processing. That is, as long as this function can be realized, any hardware (electronic circuit or the like), software (program), or a combination thereof may be used.

  When the above-described image processing method according to an embodiment of the present invention is implemented as a program, the program is downloaded from an external server or the like to an information processing apparatus that executes the method, or in the form of a computer-readable medium It is preferable that it is distributed by. Examples of the computer readable medium include a CD-ROM, DVD, magnetic tape, flexible disk, magneto-optical disk, and hard disk.

  As mentioned above, although this invention was demonstrated using embodiment shown in drawing, these are only an illustration and those skilled in this technical field can variously be within the range which does not deviate from the range and the meaning of this invention. It will be understood that modifications and variations are possible. Accordingly, the scope of the invention should not be determined by the described embodiments, but by the technical spirit described in the claims.

It is a block diagram which shows the function of the color correction processing apparatus 1000 which concerns on one Embodiment of this invention. It is a figure of a color image, (a) is an original color image to be processed, (b) is a first frame image, (c) is a second frame image, and (d) is a third frame. (E) is a fourth frame image. This color image is attached to the property submission form. It is a time chart which shows the output timing of the 1st-4th frame image. It is a flowchart of the color correction process which the color correction processing apparatus 1000 which concerns on one Embodiment of this invention performs. It is a flowchart of the color correction process which the color correction processing apparatus 1000 which concerns on one Embodiment of this invention performs.

DESCRIPTION OF SYMBOLS 10 Color processing part 20 Frame image generation / storage part 30 Image output part 110 R / G level comparison part 120 Lightness calculating part 210 1st frame image generation part 220 2nd frame image generation part 230 3rd frame image generation part 240 4th Frame image generation unit 310 Frame image switching control unit 1000 Color correction processing device

Claims (14)

A color correction processing device that performs predetermined color correction on color image data,
Pixels constituting the color image data, the lightness of a red part composed of pixels whose R level is larger than the G level, and pixels constituting the color image data, the G level being lower than the R level A color correction processing apparatus characterized by changing the brightness of a green portion composed of large pixels at different periods. Brightness of the red portion and the green part is varied within the variation range, their variation range, respectively, according to claim 1, wherein the red portion and said changed according to the hue of the green part, wherein Rukoto Color correction processing device. Brightness of the red portion and the green part is varied within the variation range, their variation range, respectively, claim 1 or to the red portion and the changes accordingly the saturation of the green part, wherein Rukoto color correction processing apparatus according to 2. The color correction processing apparatus according to any one of claims 1 to 3 , wherein the brightness of the red portion and the green portion changes stepwise with different periods . The color correction processing apparatus according to claim 4 , wherein the brightness of the red part and the green part changes in two stages with different periods . A color correction processing method for performing color correction on color image data,
For each pixel constituting the color image data , the R level and the G level are compared, and a pixel having a larger R level is identified as a red portion, and a pixel having a greater G level is identified as a green portion. Stages,
A brightness change step of changing at different periods and brightness of the brightness and the green portion of the red portion of the above identified,
A color correction processing method comprising: Brightness of the red portion and the green part is varied within the variation range, their variation range, respectively, according to claim 6, characterized in Rukoto is changed according to the hue of the red portion and the green portion Color correction processing method. Brightness of the red portion and the green part is varied within the variation range, their variation range, respectively, according to claim 6 or, characterized in Rukoto is changed according to the saturation of the red portion and the green portion 8. The color correction processing method according to 7 . Wherein the brightness change stage, color correction processing method according to any one of claims 6 to 8, characterized in that the stepwise change of the brightness of the red portion and the green portion at different periods. The color correction processing method according to claim 9 , wherein the brightness of the red portion and the green portion is changed in two stages at different periods . A program for causing a computer to execute the color correction processing method according to any one of claims 6 to 10 . A computer readable medium storing the program according to claim 11 . Electronic circuitry for performing a color correction processing method according to any one of claims 6 to 10. A display device storing the electronic circuit according to claim 13 .

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