Image converting method and device

Patent metadata

Field	Value
Publication number	US-10332485-B2
Application number	US-201515773047-A
Country	US
Kind code	B2
Filing date	Nov 17, 2015
Priority date	Nov 17, 2015
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

An image converting method and image converting device that are able to properly reproduce the appearance of the original image even in an environment having different brightness. The image converting method includes a JND corresponding value width acquisition step of, on the basis of input image data, acquiring a JND corresponding value width corresponding to a reflectance component of the input image data, a luminance width acquisition step of acquiring a luminance width corresponding to the JND corresponding value width or a value obtained by converting the JND corresponding value width in accordance with a predetermined rule using, as a reference, a second reference luminance different from a first reference luminance.

First claim

The invention claimed is:

1. An image converting method comprising:
a JND corresponding value width acquisition step of, on the basis of input image data, acquiring a JND corresponding value width corresponding to a reflectance component of the input image data;
a luminance width acquisition step of acquiring a luminance width corresponding to the JND corresponding value width or a value obtained by converting the JND corresponding value width in accordance with a predetermined rule using, as a reference, a second reference luminance different from a first reference luminance, wherein the first reference luminance is used as a reference when acquiring the JND corresponding value width;
a corrected reflectance component acquisition step of acquiring a gradation width corresponding to the luminance width as a corrected reflectance component; and
a mixing step of generating output image data by mixing an illumination light component of the input image data or a corrected illumination light component thereof and the corrected reflectance component.

2. The image converting method of claim 1 , wherein the predetermined rule uses a predetermined correction function, wherein the predetermined correction function comprises at least one of a multiplication coefficient or a division coefficient, an addition constant or a subtraction constant, and a table or a formula in which the JND corresponding value width and the value obtained by converting the JND corresponding value width are associated with each other.

3. The image converting method of claim 1 , wherein the JND corresponding value width acquisition step comprises acquiring, as the JND corresponding value width, the difference between a JND corresponding value corresponding to the illumination light component of the input image data and a JND corresponding value corresponding to all light components of the input image data.

4. The image converting method of claim 3 , further comprising a gradation/luminance conversion step of converting gradation values of the illumination light component and the all light components of the input image data into luminances, wherein
the JND corresponding value width acquisition step comprises acquiring the JND corresponding value width corresponding to the difference between the luminances.

5. The image converting method of claim 1 , wherein the first reference luminance is a luminance corresponding to the illumination light component or the all light components of the input image data.

6. The image converting method of claim 1 , wherein the second reference luminance is a luminance obtained by correcting the first reference luminance on the basis of intensity of external light, or a luminance set by a user.

7. The image converting method of claim 1 , wherein all the steps are performed on a pixel by pixel basis.

8. An image converting device comprising:
a JND corresponding value width acquisition unit configured to, on the basis of input image data, acquire a JND corresponding value width corresponding to a reflectance component of the input image data;
a luminance width acquisition unit configured to acquire a luminance width corresponding to the JND corresponding value width or a value obtained by converting the JND corresponding value width in accordance with a predetermined rule using, as a reference, a second reference luminance different from a first reference luminance, wherein the first reference luminance is used as a reference when acquiring the JND corresponding value width;
a corrected reflectance component acquisition unit configured to acquire a gradation width corresponding to the luminance width as a corrected reflectance component; and
a mixer configured to generate output image data by mixing an illumination light component of the input image data or a corrected illumination light component thereof and the corrected reflectance component.

Assignees

• Eizo Corp

Inventors

• Aoki Reo
• Higashi Masafumi
• Bamba Yusuke

Classifications

• G09G2320/0626

  for control of overall brightness · CPC title

• G09G5/10 Primary

  Intensity circuits · CPC title

• G09G2340/10

  Mixing of images, i.e. displayed pixel being the result of an operation, e.g. adding, on the corresponding input pixels · CPC title

• G09G5/36

  characterised by the display of a graphic pattern, e.g. using an all-points-addressable [APA] memory · CPC title

• G09G5/026

  Control of mixing and/or overlay of colours in general (G09G5/022 and G09G5/024 take precedence) · CPC title