Image processor, image display device, and image processing method for correcting input image
According to one embodiment, an image processor includes a processor. The processor implements acquiring a first image and first information. The first information indicates a condition of a first projection surface. The first information includes a first color gamut of the first projection surface. The processor implements deriving a second color gamut according to the first color gamut derived by using the first information. The processor implements converting a chromaticity of the first image to obtain a second image. Each pixel of the second image has a color included in the second color gamut. The processor implements generating a first converted image by correcting the second image based on the first color gamut.
1. An image processor, comprising:
a processor configured to implement at least:
acquiring a first image, and first information indicating a condition of a first projection surface, the first information including a first color gamut of the first projection surface;
deriving a second color gamut based on the first color gamut;
converting a chromaticity of the first image to obtain a second image, each pixel of the second image having a color included in the second color gamut; and
generating a first converted image by correcting the second image based on the first color gamut.
2. The image processor according to claim 1 , wherein
the second image has a first color,
the first projection surface has a second color,
a third color is based on a difference between the first color and the second color,
the first converted image has a fourth color, and
a color difference ΔEab between the third color and the fourth color is 6.0 or less.
3. The image processor according to claim 1 , wherein
the second color gamut includes a first region not overlapping the first color gamut and a second region overlapping the first color gamut, and
an area of the first region is less than an area of the second region.
4. The image processor according to claim 1 , further comprising a memory storing a third color gamut, and
the deriving includes setting the second color gamut based on the first color gamut and the third color gamut.
5. The image processor according to claim 4 , wherein
at least a portion of the second color gamut is included in the first color gamut, and
at least a portion of the third color gamut is included in the second color gamut.
6. The image processor according to claim 4 , wherein
the deriving includes setting the second color gamut so that an area of a region where the first color gamut and the second color gamut overlap increases as a difference between the first color gamut and the third color gamut increases.
7. The image processor according to claim 4 , wherein
the first color gamut includes a first color gamut portion and a second color gamut portion,
the processor is further configured to implement color gamut modifying, the color gamut modifying including modifying the first color gamut portion to a third color gamut portion and modifying the second color gamut portion to a fourth color gamut portion based on the first color gamut portion, the second color gamut portion, and the third color gamut,
the deriving further includes deriving the second color gamut based on the third color gamut portion and the fourth color gamut portion, and
the generating further includes generating the first converted image by correcting the second image based on the third color gamut portion and the fourth color gamut portion.
8. The image processor according to claim 7 , wherein
an area of a region where the third color gamut, the third color gamut portion, and the fourth color gamut portion overlap is greater than an area of a region where the third color gamut, the first color gamut portion, and the second color gamut portion overlap.
9. The image processor according to claim 7 , wherein
an area of a region where the first color gamut portion and the third color gamut portion overlap is greater than an area of a region where the first color gamut portion and the third color gamut portion do not overlap, and
an area of a region where the second color gamut portion and the fourth color gamut portion overlap is greater than an area of a region where the second color gamut portion and the fourth color gamut portion do not overlap.
10. The image processor according to claim 7 , wherein
the sum of an area of a region where the third color gamut, the third color gamut portion, and the fourth color gamut portion overlap, an area of a region where the first color gamut portion and the third color gamut portion overlap, and an area of a region where the second color gamut portion and the fourth color gamut portion overlap is larger than the sum of an area of a region where the third color gamut, the first color gamut portion, and the second color gamut portion overlap, an area of a region where the first color gamut portion and the third color gamut portion do not overlap, and a surface area of a region where the second color gamut portion and the fourth color gamut portion do not overlap.
11. The image processor according to claim 1 , wherein
the processor is further configured to implement luminance mapping, and
the luminance mapping includes converting a luminance of the second image while maintaining a chromaticity of the second image based on the first color gamut, the second color gamut, and a luminance distribution inside a region of at least a portion of the second image.
12. The image processor according to claim 1 , wherein
the acquiring further includes acquiring second information indicating a condition of a second projection surface, the second information including a fourth color gamut of the second projection surface,
the deriving further includes deriving a fifth color gamut based on the fourth color gamut,
the converting further includes converting a chromaticity of the first image to obtain a fourth image, each pixel of the fourth image having a color included in the fifth color gamut, and
the generating further includes generating a second converted image by correcting the fourth image based on the fourth color gamut, wherein
a hue of the first projection surface is different from a hue of the second projection surface,
a difference between a hue of the second image and the hue of the first projection surface is smaller than a difference between the hue of the second image and the hue of the second projection surface, and
a difference between a hue of the fourth image and the hue of the second projection surface is smaller than a difference between the hue of the fourth image and the hue of the first projection surface.
13. An image display device, comprising:
an image processor; and
a projector,
the image processor including
a processor configured to implement at least:
acquiring a first image, and first information indicating a condition of a first projection surface, the first information including a first color gamut of the first projection surface;
deriving a second color gamut based on the first color gamut;
converting a chromaticity of the first image to obtain a second image, each pixel of the second image having a color included in the second color gamut; and
generating a first converted image by correcting the second image based on the first color gamut, wherein
the projector is configured to display the first converted image by projecting the first converted image onto the first projection surface.
14. The image display device according to claim 13 , further comprising a camera configured to image the first projection surface.
15. An image processing method, comprising:
acquiring a first image, and first information indicating a condition of a first projection surface, the first information including a first color gamut of the first projection surface;
deriving a second color gamut based on the first color gamut;
converting a chromaticity of the first image to obtain a second image, each pixel of the second image having a color included in the second color gamut; and
generating a first converted image by correcting the second image based on the first color gamut.