Image processing device, image displaying system, image processing method, and image processing program

Abstract

The present invention has a purpose of improving the ease of watching images.　This image processing device (10) comprises: an acquisition unit (11) that acquires a left-eye source image (101L) and a right-eye source image (101R); a generation unit (13, 13B, 13C) that generates a left-eye displayed image (105L) and a right-eye displayed image (105R) on the basis of the left-eye source image and the right-eye source image acquired by the acquisition unit; and an output unit (14) that outputs the left-eye displayed image and the right-eye displayed image generated by the generation unit. The generation unit corrects at least one of the left-eye source image and the right-eye source image such that the color difference between the left-eye displayed image and the right-eye displayed image has a predetermined value.

Description

Image processing device, image display system, image processing method, and image processing program

[0001] The present invention relates to an image processing device, an image display system, an image processing method, and an image processing program.

[0002] For example, as disclosed in Patent Document 1, a stereo presentation method is used in which separate images are presented to the left and right eyes and the images are presented in three dimensions (3D) based on binocular parallax. However, such a stereo presentation method leaves room for improvement in terms of visibility, as the presented images may appear unnatural or the sense of depth may be difficult to perceive.

[0003] JP 2016-177281 A

[0004] According to a first aspect of the present invention, there is provided an image processing device comprising: an acquisition unit that acquires a source image for the left eye and a source image for the right eye; a generation unit that generates a display image for the left eye and a display image for the right eye based on the source image for the left eye and the source image for the right eye acquired by the acquisition unit; and an output unit that outputs the display image for the left eye and the display image for the right eye generated by the generation unit, wherein the generation unit corrects at least one of the source image for the left eye and the source image for the right eye so that the color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

[0005] According to a second aspect of the present invention, there is provided an image display system comprising: an image processing device according to the above aspect; and a display device having a display unit capable of displaying a display image for the left eye and a display image for the right eye output from the output unit.

[0006] According to a third aspect of the present invention, there is provided an image processing method including acquiring a source image for the left eye and a source image for the right eye, generating a display image for the left eye and a display image for the right eye based on the acquired source image for the left eye and the source image for the right eye, and outputting the generated display image for the left eye and the display image for the right eye, wherein in generating the display image for the left eye and the display image for the right eye, at least one of the source image for the left eye and the source image for the right eye is corrected so that a color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

[0007] According to a fourth aspect of the present invention, there is provided an image processing program that causes a computer to acquire a source image for the left eye and a source image for the right eye, generate a display image for the left eye and a display image for the right eye based on the acquired source image for the left eye and the source image for the right eye, and output the generated display image for the left eye and the display image for the right eye, wherein in generating the display image for the left eye and the display image for the right eye, the image processing program corrects at least one of the source image for the left eye and the source image for the right eye so that a color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

[0008] 1 is a diagram showing an example of the appearance of an image display system according to a first embodiment; FIG. 2 is a functional block diagram showing an example of an image display system according to the first embodiment; FIG. 3 is a diagram showing an example of a source image that appears stereoscopically according to the first embodiment, and a source image for the left eye and a source image for the right eye included in the source image; FIG. 4 is a diagram showing an example of a display image for the left eye and a display image for the right eye that are generated by correcting each pixel in each of the source image for the left eye and the source image for the right eye according to the first embodiment; FIG. 5 is a diagram showing an example of a display image including a display image for the left eye and a display image for the right eye according to the first embodiment; FIG. 6 is a flowchart showing an example of an image processing method according to the first embodiment; FIG. 7 is a diagram showing an example of a display image for the left eye and a display image for the right eye that are generated by correcting each pixel in each of the source image for the left eye and the source image for the right eye according to the second embodiment; FIG. 8 is a flowchart showing an example of an image processing method in an image display system according to a third embodiment; FIG. 9 is a functional block diagram showing an example of an image display system according to a fourth embodiment; FIG. 10 is a flowchart showing an example of an image processing method in an image display system according to the fourth embodiment; FIG. 11 is a diagram showing an example of an image display system according to a fifth embodiment; FIG. 12 is a diagram showing an example of an image display system according to a sixth embodiment.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the contents described below. In addition, in order to explain the embodiments, the drawings are shown with appropriate scale changes, such as enlarging or emphasizing some parts, and the shape, dimensions, etc. of the actual product may differ.

[0010] [First Embodiment] A first embodiment will be described. Fig. 1 is a diagram showing an example of the appearance of an image display system according to the first embodiment. As shown in Fig. 1, the image display system 1 in this embodiment is, for example, a portable computer terminal 2. The computer terminal 2 as the image display system 1 includes a housing 3, an image processing device 10 provided in the housing 3, and a display device 20. The image processing device 10 and the display device 20 are provided in the same housing 3. Examples of computer terminals 2 configured to include the image processing device 10 and the display device 20 in the same housing 3 include game terminals, smartphones, tablet terminals, etc.

[0011] 2 is a functional block diagram showing an example of an image display system according to the first embodiment. As shown in FIG. 2, the image processing device 10 acquires data of a source image 101 that is the basis of an image to be displayed on the display device 20. The image processing device 10 generates a display image 105 to be displayed on the display device 20 based on the acquired source image 101 data. The image processing device 10 outputs data of the generated display image 105 to the display device 20. The display device 20 displays the display image 105 that appears three-dimensional based on the data output from the image processing device 10. The image processing device 10 functionally includes an acquisition unit 11, a storage unit 12, a generation unit 13, and an output unit 14.

[0012] FIG. 3 is a diagram illustrating an example of a stereoscopic source image according to the first embodiment, and a left-eye source image and a right-eye source image included in the source image. The acquisition unit 11 acquires a left-eye source image 101L and a right-eye source image 101R. The acquisition unit 11 acquires one source image 101 as a left-eye source image 101L and a right-eye source image 101R. As illustrated in FIG. 3, the source image 101 is an image that appears stereoscopically and includes a left-eye source image 101L and a right-eye source image 101R. The source image 101 may not be an image that appears stereoscopically, but may be a so-called two-dimensional image. In this case, the image processing device 10 may generate a left-eye source image 101L and a right-eye source image 101R as the stereoscopic source image 101 based on the source image, which is a two-dimensional image.

[0013] The acquisition unit 11 shown in FIG. 2 may acquire the source image 101, for example, from outside the housing 3 via a network such as the Internet, a public wireless communication network, Wi-Fi, Bluetooth (registered trademark), or infrared communication. The source image 101 acquired by the acquisition unit 11 may be stored in various portable storage media such as a USB memory, an SD card, or a CD-ROM. In this case, by connecting the storage medium to the computer terminal 2, the acquisition unit 11 reads and acquires the source image 101 from the storage medium. The source image 101 may also be stored in advance in the storage unit 12, which will be described later.

[0014] The storage unit 12 stores, for example, the acquired source image 101, a display image 105 (described later), various setting information, a program for executing processing, etc. The storage unit 12 may include a storage device built into the image processing device 10.

[0015] The generation unit 13 generates a display image 105L for the left eye and a display image 105R for the right eye as a display image 105 to be displayed on the display device 20, based on the source image 101L for the left eye and the source image 101R for the right eye acquired by the acquisition unit 11. The display image 105 is an image that appears stereoscopic when displayed on the display device 20, and includes the source image 101L for the left eye and the source image 101R for the right eye.

[0016] The generation unit 13 performs image processing based on a preset program to add a color difference ΔE00 between the left eye display image 105L and the right eye display image 105R. The generation unit 13 generates a display image 105 including the left eye display image 105L and the right eye display image 105R to which the color difference ΔE00 has been added. By adding a color difference between the left eye display image 105L and the right eye display image 105R, when the display image 105 is displayed (presented) on the display device 20, a user viewing the display image 105 is prevented from feeling uncomfortable with the display image 105 or from having difficulty perceiving a sense of depth, etc.

[0017] The generation unit 13 corrects at least one of the left eye source image 101L and the right eye source image 101R so that the color difference between the left eye display image 105L and the right eye display image 105R becomes a predetermined value. The color difference between the left eye display image 105L and the right eye display image 105R is a color difference ΔE00 in which coefficients corresponding to the lightness, saturation, and hue values ​​are introduced to correct for the visual non-uniformity of CIELAB. More specifically, the generation unit 13 corrects at least one of the left eye source image 101L and the right eye source image 101R so that the color difference ΔE00 between the left eye display image 105L and the right eye display image 105R, calculated based on CIE DE2000 when a 2-degree CIE standard illuminant D65 is used as the reference light, falls within a predetermined range.

[0018] The generation unit 13 preferably generates the left eye display image 105L and the right eye display image 105R so that the color difference ΔE00 between the left eye display image 105L and the right eye display image 105R is within the range of 0.98≦ΔE00≦4.29, for example. Furthermore, the generation unit 13 more preferably generates the left eye display image 105L and the right eye display image 105R so that the color difference ΔE00 between the left eye display image 105L and the right eye display image 105R is within the range of 1.74≦ΔE00≦4.29. By keeping the color difference ΔE00 between the left eye display image 105L and the right eye display image 105R within the above range, it is possible to obtain the effect of improving visual contrast while suppressing the occurrence of binocular rivalry.

[0019] 4 is a diagram showing an example of a left-eye display image and a right-eye display image generated by correcting the pixels in each of the left-eye source image and the right-eye source image according to Embodiment 1. As shown in Fig. 4, each of the left-eye source image 101L and the right-eye source image 101R has a plurality of pixels PxL1, PxL2, ..., PxR1, PxR2, ... arranged in a matrix in the width direction and height direction of each image.

[0020] In each of the left-eye source image 101L and the right-eye source image 101R, the pixels PxL1, PxL2, ..., PxR1, PxR2, ... display a color corresponding to the image to be displayed. In each of the left-eye source image 101L and the right-eye source image 101R, the pixels PxL1, PxL2, ..., PxR1, PxR2, ... are set with RGB color coordinates corresponding to the color to be displayed. In this embodiment, color coordinates in the L*a*b* display are used as the RGB color coordinates of the pixels PxL1, PxL2, ..., PxR1, PxR2, .... The color coordinates in the L*a*b* display vary depending on the reference light source. In this embodiment, values ​​calculated using CIE standard illuminant D65 with a 2-degree field of view, which is standard for outdoor daylight, as the reference light are used.

[0021] The generation unit 13 generates the left eye display image 105L and the right eye display image 105R using the color coordinate values ​​of each of the multiple pixels PxL1, PxL2, ..., PxR1, PxR2, ... that make up the left eye source image 101L and the right eye source image 101R. More specifically, the generation unit 13 acquires the RGB color coordinates of each of the multiple pixels PxL1, PxL2, ..., PxR1, PxR2, ... that make up the left eye source image 101L and the right eye source image 101R. The RGB color coordinates of each of the multiple pixels PxL1, PxL2, ..., PxR1, PxR2, ... that make up the source image 101L for the left eye and the source image 101R for the right eye are included in the data of each of the multiple pixels PxL1, PxL2, ..., PxR1, PxR2, ... that make up the source image 101L for the left eye and the source image 101R for the right eye.

[0022] The generation unit 13 corrects the RGB color coordinates of each of the multiple pixels in at least one of the left eye source image 101L and the right eye source image 101R so as to create a color difference between pixels PxL1, PxL2, ... in the left eye source image 101L and pixels PxR1, PxR2, ... in the right eye source image 101R that are at positions corresponding to pixels PxL1, PxL2, ... in the left eye source image 101L. The generation unit 13 corrects the RGB color coordinates of each of the multiple pixels in at least one of the left eye source image 101L and the right eye source image 101R, and generates the left eye display image 105L and the right eye display image 105R.

[0023] The generation unit 13 uses either the left eye source image 101L or the right eye source image 101R as a reference, and corrects the RGB color coordinates of each of the multiple pixels in the other of the left eye source image 101L and the right eye source image 101R, thereby generating a left eye display image 105L and a right eye display image 105R. For example, in the example of Fig. 4, the generation unit 13 uses the left eye source image 101L as a reference, and corrects the RGB color coordinates of each of the multiple pixels based on the right eye source image 101R.

[0024] The generation unit 13 corrects the RGB color coordinates of each of the multiple pixels PxR1, PxR2, ... that make up the right-eye source image 101R, and generates the corrected image as the right-eye display image 105R. On the other hand, the reference left-eye source image 101L does not correct the RGB color coordinates of each of the multiple pixels PxL1, PxL2, ... that make up the left-eye source image 101L, and the left-eye source image 101L is used as is as the left-eye display image 105L.

[0025] In the above description, the generation unit 13 generates the right-eye display image 105R by correcting the RGB color coordinates of each of the plurality of pixels PxR1, PxR2, ... based on the right-eye source image 101R, using the left-eye source image 101L as a reference, but this is not limiting. The generation unit 13 may also generate the left-eye display image 105L by correcting the RGB color coordinates of each of the plurality of pixels PxL1, PxL2, ... based on the left-eye source image 101L, using the right-eye source image 101R as a reference.

[0026] When correcting the RGB color coordinates of each of the plurality of pixels, the generation unit 13 corrects the color coordinates of at least one of the three colors, R (red), G (green), and B (blue), in the L*a*b* display. The generation unit 13 may correct the color coordinates of two or all three of the three colors, R (red), G (green), and B (blue), in the L*a*b* display, for the plurality of pixels.

[0027] Furthermore, when correcting the color coordinates of at least one color in the L*a*b* display for each of the multiple pixels, the generation unit 13 may correct the color coordinates by a preset value. The color coordinates of R (red), G (green), and B (blue) in the L*a*b* display are each set to 128 gradation values ​​from 1 to 128. The generation unit 13 may correct the color coordinates of at least one color among the color coordinates of the three colors R (red), G (green), and B (blue) in the L*a*b* display for each of the multiple pixels so that the color coordinates decrease by a preset value (for example, 2).

[0028] Here, it is preferable that the generation unit 13 sets the correction amount of the color coordinates in the L*a*b* display so that the color difference ΔE00 between the left eye display image 105L and the right eye display image 105R generated in this manner falls within the predetermined range.

[0029] The color difference ΔE00 at each pixel between the left eye display image 105L and the right eye display image 105R is calculated according to a document describing a calculation method (Gaurav Sharma, et. al., The CIEDE2000 Color-Difference Formula: Implementation Notes, Supplementary Test Data, and Mathematical Observations, COLOR research and application, Volume 30, Number 1, February 2009, pp. 111-115, 2009). 2005) and a spreadsheet distributed by the author of the document (http: / / www2.ecce.rochester.edu / ~gsharma / ciede2000 / ), the color coordinates of each pixel in the L*a*b* display are used to calculate the color coordinates from the L* value, a* value, and b* value.

[0030] The generation unit 13 further generates a display image 105 including the left eye display image 105L and the right eye display image 105R to display the left eye display image 105L and the right eye display image 105R on the display device 20 as a single display image 105. The output unit 14 outputs data of the display image 105 including the left eye display image 105L and the right eye display image 105R generated by the generation unit 13 to the display device 20.

[0031] 2, the display device 20 is a display unit incorporated in the housing 3, and includes a display control unit 22 and a display unit 21 capable of displaying a display image 105. The display control unit 22 causes the display unit 21 to display the display image 105 based on data of the display image 105, including a display image 105L for the left eye and a display image 105R for the right eye, output from the output unit 14. The display unit 21 may display the display image 105L for the left eye and the display image 105R for the right eye by superimposing them on one display image 105.

[0032] 5 is a diagram showing an example of a display image including a left-eye display image and a right-eye display image according to the first embodiment. As shown in FIG. 5 , the display image 105 displayed on the display unit 21 has pixels of a left-eye display image 105L and pixels of a right-eye display image 105R arranged in an alternating overlapping arrangement, shifted left and right. The display unit 21 is provided with a mask 25 having an opening 25s. Due to binocular parallax caused by the user's left and right eyes being separated laterally and the opening 25s in the mask 25, the user views the left-eye display image 105L of the display image 105 with his left eye and the right-eye display image 105R with his right eye.

[0033] Next, an example of an image processing method according to the embodiment will be described based on the configuration of the above-described image display system 1. Fig. 6 is a flowchart showing an example of the image processing method according to the embodiment. The image processing method according to the present embodiment includes acquiring a left-eye source image 101L and a right-eye source image 101R, generating a left-eye display image 105L and a right-eye display image 105R based on the acquired left-eye source image 101L and right-eye source image 101R, and outputting the generated left-eye display image 105L and right-eye display image 105R.

[0034] 6 , in step S1, the acquisition unit 11 acquires a left-eye source image 101L and a right-eye source image 101R. In step S2, the generation unit 13 generates a left-eye display image 105L and a right-eye display image 105R as a display image 105 to be displayed on the display device 20, based on the left-eye source image 101L and the right-eye source image 101R acquired by the acquisition unit 11. The generation unit 13 generates the left-eye display image 105L and the right-eye display image 105R so that the color difference between the left-eye display image 105L and the right-eye display image 105R is a predetermined value. The generation unit 13 generates the left-eye display image 105L and the right-eye display image 105R so that the color difference ΔE00 between the left-eye display image 105L and the right-eye display image 105R is within the range of 0.98≦ΔE00≦4.29, for example.

[0035] In step S3, the output unit 14 outputs the left eye display image 105L and the right eye display image 105R generated by the generation unit 13. In step S4, the display unit 21 displays the display image 105 including the left eye display image 105L and the right eye display image 105R. As a result, the user is presented with the display image 105 in which the color difference between the left eye display image 105L and the right eye display image 105R has been corrected to a predetermined value, thereby achieving the effect of improving visual contrast while suppressing binocular rivalry.

[0036] In this manner, according to the present embodiment, the color difference between the left eye display image 105L and the right eye display image 105R is corrected to a predetermined value. By being presented with the corrected display image 105, the user can improve the visibility of the stereoscopically presented image.

[0037] In the above embodiment, the image display system 1 includes, for example, a computer system. The image display system 1 reads a detection program stored in the storage unit 12 and executes various processes in accordance with the detection program. The detection program, for example, causes the computer to acquire a left-eye source image 101L and a right-eye source image 101R, generate a left-eye display image 105L and a right-eye display image 105R based on the acquired left-eye source image 101L and right-eye source image 101R, and output the generated left-eye display image 105L and right-eye display image 105R. In generating the left-eye display image 105L and the right-eye display image 105R, the program corrects at least one of the left-eye source image 101L and the right-eye source image 101R so that a color difference between the left-eye display image 105L and the right-eye display image 105R becomes a predetermined value. The detection program may be provided in a form recorded on a computer-readable storage medium.

[0038] Second Embodiment A second embodiment will be described. In this embodiment, components similar to those in the above-described embodiments are denoted by the same reference numerals, and descriptions thereof will be omitted or simplified. In an image display system 1B according to this embodiment shown in FIG. 2, a generation unit 13B corrects the RGB color coordinates of each of a plurality of pixels in both a left-eye source image 101L and a right-eye source image 101R, and generates a left-eye display image 105L and a right-eye display image 105R.

[0039] 7 is a diagram showing an example of a left-eye display image and a right-eye display image generated by correcting the pixels in each of the left-eye source image and the right-eye source image according to the second embodiment. As shown in FIG. 7, the generation unit 13B generates a left-eye display image 105L by correcting the RGB color coordinates of each of a plurality of pixels based on the left-eye source image 101L. The generation unit 13B also generates a right-eye display image 105R by correcting the RGB color coordinates of each of a plurality of pixels based on the right-eye source image 101R.

[0040] At this time, the correction amount of the RGB color coordinates of each of the plurality of pixels PxL1, PxL2, ... constituting the left eye source image 101L, which is corrected when generating the left eye display image 105L from the left eye source image 101L, is made different from the correction amount of the RGB color coordinates of each of the plurality of pixels PxR1, PxR2, ... constituting the right eye source image 101R, which is corrected when generating the right eye display image 105R from the right eye source image 101R. In this way, the generation unit 13B corrects the left eye source image 101L and the right eye source image 101R so that the color difference between the left eye display image 105L and the right eye display image 105R becomes a predetermined value.

[0041] As described above, according to this embodiment, by correcting the RGB color coordinates of each of the multiple pixels in both the left-eye source image 101L and the right-eye source image 101R, the color difference between the left-eye display image 105L and the right-eye display image 105R is corrected to a predetermined value. As a result, the user can improve the visibility of the stereoscopically presented image by being presented with the corrected display image 105.

[0042] Third Embodiment A third embodiment will be described. In this embodiment, the same components as those in the above embodiments are assigned the same reference numerals, and their description will be omitted or simplified. Here, in the generation unit 13 in the above first embodiment, the color coordinates of each of the multiple pixels are corrected by a preset value, thereby correcting the color difference between the left eye display image 105L and the right eye display image 105R to a predetermined value. In contrast, in the image display system 1C in this embodiment, image processing is performed in the following manner.

[0043] Fig. 8 is a flowchart showing an example of an image processing method in an image display system according to the third embodiment. As shown in Fig. 8, an image display system 1C according to this embodiment executes steps S1 and S2 in the image processing method according to the first embodiment in the same manner, and in step S2, a generation unit 13C corrects color coordinates in the L*a*b* display.

[0044] In step S5 of this embodiment, which is performed following step S2, the color difference ΔE00 between the generated left eye display image 105L and right eye display image 105R is calculated. Then, in step S6, the generation unit 13C determines whether the calculated color difference ΔE00 is within the predetermined range.

[0045] If the color difference ΔE00 between the generated left eye display image 105L and right eye display image 105R is within a preset range, the process proceeds to steps S3 and S4, where the left eye display image 105L and right eye display image 105R are output and displayed. On the other hand, if the color difference ΔE00 between the generated left eye display image 105L and right eye display image 105R is not within the preset range in step S6, the process returns to step S2, where the correction amount of the R (red), G (green), and B (blue) color coordinates in the L*a*b* display is changed, and the left eye display image 105L and right eye display image 105R are generated again.

[0046] In this way, the correction amount of the color coordinates of R (red), G (green), and B (blue) in the L*a*b* display may be adjusted until the color difference ΔE00 between the generated left eye display image 105L and right eye display image 105R falls within a predetermined range.

[0047] [Fourth Embodiment] A fourth embodiment will now be described. FIG. 9 is a functional block diagram showing an example of an image display system according to the fourth embodiment. In this embodiment, components similar to those in the above embodiments are denoted by the same reference numerals, and their description will be omitted or simplified. As shown in FIG. 9, in an image display system 1D according to this embodiment, an image processing device 10D includes an evaluation receiving unit 15. The evaluation receiving unit 15 receives an evaluation of a display image 105 displayed on the display unit 21, for example, by a user inputting the evaluation to an operation input unit 7 (see FIG. 1) provided on the housing 3. Specifically, a user who views the presented display image 105 inputs an evaluation of visibility, etc., via the operation input unit 7. The evaluation receiving unit 15 receives the input evaluation. A generation unit 13D corrects a left-eye display image 105L and a right-eye display image 105R based on the received evaluation.

[0048] Fig. 10 is a flowchart showing an example of an image processing method in an image display system according to the fourth embodiment. As shown in Fig. 10, an image display system 1D according to this embodiment executes steps S1 and S2 in the image processing method according to the first embodiment in the same manner, and in step S2, a generation unit 13D corrects color coordinates of R (red), G (green), and B (blue) in the L*a*b* display.

[0049] In step S7 of this embodiment, which is performed following step S2, the user is asked to evaluate the display image 105 displayed on the display unit 21 based on the generated display image for the left eye 105L and display image for the right eye 105R, for example by displaying a message on the display unit 21.

[0050] As a result, if the user gives a good evaluation (e.g., an evaluation that it is "easy to see") for the displayed image 105 in step S8, the process proceeds to steps S3 and S4, where the left eye display image 105L and the right eye display image 105R are output and displayed. On the other hand, if the user does not give a good evaluation for the displayed image 105 in step S8 (e.g., an evaluation that it is "difficult to see"), the process returns to step S2, where the correction amounts for the color coordinates of R (red), G (green), and B (blue) in the L*a*b* display are changed, and the left eye display image 105L and the right eye display image 105R are generated again.

[0051] As described above, according to the present embodiment, the visibility of the image can be further improved by receiving user evaluations of the display image 105 displayed on the display unit 21 and correcting the left eye display image 105L and the right eye display image 105R in accordance with the evaluations. This makes it possible to more effectively improve the visibility of the image, for example, by addressing individual differences in the display unit 21, differences in specifications due to specifications, variations in evaluations among multiple users, and the like.

[0052] Fifth Embodiment A fifth embodiment will be described. FIG. 11 is a diagram showing an example of an image display system according to the fifth embodiment. In this embodiment, the same components as those in the above embodiments are denoted by the same reference numerals, and their description will be omitted or simplified. As shown in FIG. 11 , a display device 20E of an image display system 1E in this embodiment includes a display unit 21L for the left eye and a display unit 21R for the right eye. The left eye display unit 21L displays a display image 105L for the left eye. The right eye display unit 21R displays a display image 105R for the right eye. The display device 20E is configured to be wearable on the user's head, for example, like glasses or goggles.

[0053] Even in this configuration, the left eye display image 105L and the right eye display image 105R are generated using the same configuration as those shown in the first to fourth embodiments so that the color difference between the left eye display image 105L and the right eye display image 105R is a predetermined value. Then, the generated left eye display image 105L is displayed on the left eye display unit 21L, and the right eye display image 105R is displayed on the right eye display unit 21R.

[0054] Thus, according to this embodiment, the color difference between the left eye display image 105L and the right eye display image 105R is corrected to a predetermined value, thereby improving the visibility of the image presented three-dimensionally.

[0055] Sixth Embodiment A sixth embodiment will now be described. Fig. 12 is a diagram showing an example of an image display system according to the sixth embodiment. In this embodiment, components similar to those in the above-described embodiments are denoted by the same reference numerals, and their description will be omitted or simplified. As shown in Fig. 12, in an image display system 1F according to this embodiment, an image processing device 10F and a display device 20F are separate entities.

[0056] In this case, the image processing device 10F may be incorporated into a computer device such as a personal computer, a tablet terminal, or a smartphone. Meanwhile, the display device 20F is configured to be wearable on the user's head, like the glasses or goggles shown in the fifth embodiment. The display device 20F may also be a stationary monitor device provided separately from the image processing device 10F, or a monitor device wearable on the user's head. The image processing device 10F and the display device 20F are configured to be connectable via a wired or wireless network.

[0057] Even with such a configuration, the visibility of the image presented three-dimensionally by the display device 20F can be improved by correcting the color difference between the left eye display image 105L and the right eye display image 105R to a predetermined value.

[0058] (Image Creation) Japanese text consisting of gray characters (RGB = 128, 128, 128) of various sizes was placed on a white background (RGB = 255, 255, 255) to create image P1 shown in Table 1. Similarly, images P2 to P16 shown in Table 1 were created by reducing any of the RGB values ​​of the gray characters.

[0059]

[0060] (Calculation of Color Difference) The color difference ΔE00 between the right eye display image and the left eye display image for each display image in the examples and comparative examples is also shown in the table.

[0061]

[0062] The color difference ΔE00 between the characters in the image set was converted from RGB color coordinates to L*a*b* color coordinates using a color code conversion tool (https: / / syncer.jp / color-converter). Next, the color difference ΔE00 was calculated based on the calculation method described in Gaurav Sharma, et al., "The CIEDE2000 Color-Difference Formula: Implementation Notes, Supplementary Test Data, and Mathematical Observations, COLOR research and application, Volume 30, Number 1, February 2009" 2005) and a spreadsheet distributed by the authors of the literature (http: / / www2.ece.rochester.edu / ~gsharma / ciede2000 / ), the L*, a*, and b* values ​​of the characters in the two images were calculated.

[0063] (Image Evaluation) A Nintendo 3DS (trade name manufactured by Nintendo Co., Ltd.) was used as the image display device. The image pairs in Table 2 were converted into a file format readable by the 3DS using the "Stereo Photo Maker Ver. 4.32d for 3DS" software (http: / / stereo.jpn.org / jpn / 3ds / index.html) and displayed in stereo on the display device. Evaluation was performed based on the image pair shown in Comparative Example 1, which consisted of two identical images, and the color difference between the two images was used to determine whether there was any change in appearance compared to Comparative Example 1. This evaluation was performed on five subjects, and the evaluation was based on the number of subjects who felt the effect. The results are shown in Table 3.

[0064] Compared to Comparative Example 1, in which ΔE was 0.00, in Example 1, in which ΔE00 was 0.98, two out of five people felt that the characters were easier to read. Furthermore, in Example 2, in which ΔE00 was 1.74, three out of five people, or a majority, felt that the characters were easier to read. In Examples 2 to 8, the RGB of the image for the right eye was changed in various ways, but regardless of the color change, the majority of people felt that the images were easy to see as long as the color difference ΔE00 was 1.74 or more and 3.86 or less. On the other hand, in Examples 9 to 15, in which ΔE00 was 4.29 or more, some people felt that the images were easier to see compared to Comparative Example 1, while others found them difficult to see. This difficulty in seeing is thought to be due to binocular rivalry caused by excessively large color differences.

[0065] Although the embodiments and examples have been described above, the technical scope of the present invention is not limited to the aspects described in the above embodiments and examples. One or more of the requirements described in the above embodiments and examples may be omitted. In addition, the requirements described in the above embodiments and examples may be combined as appropriate. In addition, to the extent permitted by law, the disclosures of all documents cited in this specification and Japanese patent application No. 2022-199539 are incorporated by reference as part of the description in this text.

[0066] (Supplementary Note) This embodiment includes the contents shown in Supplementary Note 1 to Supplementary Note 9 below. (Supplementary Note 1) An image processing device comprising: an acquisition unit that acquires a source image for the left eye and a source image for the right eye, a generation unit that generates a display image for the left eye and a display image for the right eye based on the source image for the left eye and the source image for the right eye acquired by the acquisition unit, and an output unit that outputs the display image for the left eye and the display image for the right eye generated by the generation unit, wherein the generation unit corrects at least one of the source image for the left eye and the source image for the right eye so that a color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value. (Supplementary Note 2) The image processing device according to Supplementary Note 1, wherein the generation unit generates the display image for the left eye and the display image for the right eye such that a color difference ΔE00 between the display image for the left eye and the display image for the right eye, calculated based on CIE DE2000 when CIE standard illuminant D65 with a 2-degree field of view is used as reference light, is within a range of 0.98≦ΔE00≦4.29. (Supplementary Note 3) The image processing device according to Supplementary Note 2, wherein the generation unit generates the display image for the left eye and the display image for the right eye such that a color difference ΔE00 between the display image for the left eye and the display image for the right eye is within a range of 1.74≦ΔE00≦4.29. (Supplementary Note 4) The image processing device according to any one of Supplementary Notes 1 to 3, wherein the generation unit generates the display image for the left eye and the display image for the right eye using values ​​of color coordinates of each of a plurality of pixels constituting the source image for the left eye and the source image for the right eye. (Supplementary Note 5) The image processing device described in Supplementary Note 4, wherein the generation unit acquires RGB color coordinates for each of a plurality of pixels constituting the left eye source image and the right eye source image, corrects the RGB color coordinates for each of a plurality of pixels in at least one of the left eye source image and the right eye source image so that the color difference between the pixel of the left eye source image and a pixel in the right eye source image at a position corresponding to the pixel of the left eye source image becomes the specified value, and generates the left eye display image and the right eye display image.(Supplementary Note 6) The image processing device according to Supplementary Note 5, wherein the generation unit uses one of the left eye source image and the right eye source image as a reference, corrects RGB color coordinates of each of a plurality of pixels in the other of the left eye source image and the right eye source image, and generates the left eye display image and the right eye display image. (Supplementary Note 7) The image processing device according to Supplementary Note 5, wherein the generation unit corrects RGB color coordinates of each of a plurality of pixels in both the left eye source image and the right eye source image, and generates the left eye display image and the right eye display image. (Supplementary Note 8) The image processing device according to any one of Supplementary Notes 1 to 7, wherein the acquisition unit acquires one source image as the left eye source image and the right eye source image. (Supplementary Note 9) An image display system comprising: an image processing device according to any one of Supplementary Note 1 to Supplementary Note 8; and a display device having a display unit capable of displaying the left eye display image and the right eye display image output from the output unit.

[0067] 1, 1B, 1C, 1D, 1E, 1F... Image display system, 10, 10D, 10F... Image processing device, 11... Acquisition unit, 13, 13B, 13C, 13D... Generation unit, 14... Output unit, 20, 20E, 20F... Display device, 21... Display unit, 101... Source image, 101L... Source image for left eye, 101R... Source image for right eye, 105... Display image, 105L... Display image for left eye, 105L... Display image for eye, 105R... Display image for right eye

Claims

1. An image processing device comprising: an acquisition unit that acquires a source image for the left eye and a source image for the right eye; a generation unit that generates a display image for the left eye and a display image for the right eye based on the source image for the left eye and the source image for the right eye acquired by the acquisition unit; and an output unit that outputs the display image for the left eye and the display image for the right eye generated by the generation unit, wherein the generation unit corrects at least one of the source image for the left eye and the source image for the right eye so that the color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

2. The image processing device described in claim 1, wherein the generation unit generates the display image for the left eye and the display image for the right eye so that the color difference ΔE00 between the display image for the left eye and the display image for the right eye, calculated based on CIE DE2000 when CIE standard illuminant D65 with a 2-degree field of view is used as the reference light, is in the range of 0.98≦ΔE00≦4.

29.

3. The image processing device described in claim 2, wherein the generation unit generates the display image for the left eye and the display image for the right eye so that the color difference ΔE00 between the display image for the left eye and the display image for the right eye is in the range of 1.74≦ΔE00≦4.

29.

4. The image processing device described in claim 1, wherein the generation unit generates the left eye display image and the right eye display image using the color coordinate values ​​of each of the multiple pixels that make up the left eye source image and the right eye source image.

5. The image processing device described in claim 4, wherein the generation unit acquires RGB color coordinates for each of a plurality of pixels constituting the left eye source image and the right eye source image, corrects the RGB color coordinates for each of a plurality of pixels in at least one of the left eye source image and the right eye source image so that the color difference between the pixel of the left eye source image and a pixel in the right eye source image at a position corresponding to the pixel of the left eye source image becomes the specified value, and generates the left eye display image and the right eye display image.

6. The image processing device described in claim 5, wherein the generation unit uses either the source image for the left eye or the source image for the right eye as a reference, corrects the RGB color coordinates of each of a plurality of pixels in the other of the source image for the left eye and the source image for the right eye, and generates the display image for the left eye and the display image for the right eye.

7. The image processing device described in claim 5, wherein the generation unit corrects the RGB color coordinates of each of a plurality of pixels in both the source image for the left eye and the source image for the right eye, and generates the display image for the left eye and the display image for the right eye.

8. The image processing device according to claim 1, wherein the acquisition unit acquires one source image as the left eye source image and the right eye source image.

9. An image display system comprising: an image processing device according to any one of claims 1 to 8; and a display device having a display unit capable of displaying the left eye display image and the right eye display image output from the output unit.

10. The image display system according to claim 9, wherein the display unit displays the left eye display image and the right eye display image in an overlapping manner.

11. An image processing method comprising: acquiring a source image for the left eye and a source image for the right eye; generating a display image for the left eye and a display image for the right eye based on the acquired source image for the left eye and the source image for the right eye; and outputting the generated display image for the left eye and the display image for the right eye, wherein in generating the display image for the left eye and the display image for the right eye, at least one of the source image for the left eye and the source image for the right eye is corrected so that a color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

12. An image processing program that causes a computer to perform the following steps: acquire a source image for the left eye and a source image for the right eye; generate a display image for the left eye and a display image for the right eye based on the acquired source image for the left eye and the source image for the right eye; and output the generated display image for the left eye and the display image for the right eye, wherein in generating the display image for the left eye and the display image for the right eye, the program corrects at least one of the source image for the left eye and the source image for the right eye so that the color difference between the display image for the left eye and the display image for the right eye becomes a predetermined value.

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