Image display system, projector, information storage medium, and image processing method

An image display system that performs grayscale correction in accordance with the on-site environment, to display an image;

• the image display system comprising:
• image display means for displaying calibration images;
• environment determination means for determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• grayscale correction means for performing the grayscale correction, based on the on-site environmental information,
• wherein the environment determination means outputs the on-site environmental information in a state in which the calibration images are displayed, and
• wherein the grayscale correction means performs gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that indicates an environment determined when the calibration images are displayed in an ideal environment and the on-site environmental information, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region.

An image display system that performs grayscale correction in accordance with the on-site environment, to display an image;

• the image display system comprising:
• an image display section displaying calibration images;
• an environment determination section determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• a grayscale correction section performing the grayscale correction, based on the on-site environmental information,
• wherein the image display section displays the calibration images having two different grayscale values of a single color and also displays an image that has been subjected to the grayscale correction,
• wherein the environment determination section outputs two types of the on-site environmental information in a state in which the calibration images having the two grayscale values are displayed, and
• wherein the grayscale correction section performs the grayscale correction, based on a difference between two types of ideal environmental information that indicates an environment determined when the calibration images having the two grayscale values are displayed under an ideal environment and a difference between the two types of the on-site environmental information.

An image display system that performs grayscale correction in accordance with the on-site environment, to display an image;

• the image display system comprising:
• an image display section displaying calibration images;
• an environment determination section determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• a grayscale correction section performing the grayscale correction, based on the on-site environmental information,
• wherein the environment determination means outputs the on-site environmental information in a state in which the calibration images are displayed, and
• wherein the grayscale correction section performs gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that indicates an environment determined when the calibration images are displayed in an ideal environment and the on-site environmental information, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region.

A projector that performs grayscale correction in accordance with the on-site environment, to project an image, the projector comprising:

• image display means for projecting calibration images;
• environment determination means for determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• grayscale correction means for performing the grayscale correction, based on the on-site environmental information,
• wherein the image display means projects the calibration images having two different grayscale values of a single color and also projects an image that has been subjected to the grayscale correction,
• wherein the environment determination means outputs two types of the on-site environmental information in a state in which the calibration images having the two grayscale values are projected, and
• wherein the grayscale correction means performs the grayscale correction, based on a difference between two types of ideal environmental information that indicates an environment determined when the calibration images having the two grayscale values are projected under an ideal environment and a difference between the two types of the on-site environmental information.

A projector that performs grayscale correction in accordance with the on-site environment, to project an image, the projector comprising:

• an image display section projecting calibration images;
• an environment determination section determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• a grayscale correction section performing the grayscale correction, based on the on-site environmental information,
• wherein the image display means projects the calibration images having two different grayscale values of a single color and also projects an image that has been subjected to the grayscale correction,
• wherein the environment determination section outputs two types of the on-site environmental information in a state in which the calibration images having the two grayscale values are projected, and
• wherein the grayscale correction section performs the grayscale correction, based on a difference between two types of ideal environmental information that indicates an environment determined when the calibration images having the two grayscale values are projected under an ideal environment and a difference between the two types of the on-site environmental information.

A projector that performs grayscale correction in accordance with the on-site environment, to project an image, the projector comprising:

• image display means for projecting calibration images;
• environment determination means for determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• grayscale correction means for performing the grayscale correction, based on the on-site environmental information,
• wherein the environment determination means outputs the on-site environmental information in a state in which the calibration images are displayed, and
• wherein the grayscale correction means performs gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that indicates an environment determined when the calibration images are displayed in an ideal environment and the on-site environmental information, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region.

A projector that performs grayscale correction in accordance with the on-site environment, to project an image, the projector-comprising:

• an image display section projecting calibration images;
• an environment determination section determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• a grayscale correction section performing the grayscale correction, based on the on-site environmental information,
• wherein the environment determination means outputs the on-site environmental information in a state in which the calibration images are displayed, and
• wherein the grayscale correction section performs gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that indicates an environment determined when the calibration images are displayed in an ideal environment and the on-site environmental information, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region.

A computer-readable information storage medium storing a program to be used when performing grayscale correction in accordance with an on-site environment, to display an image, the program causing a computer to function as:

• display control means for causing image display means to display calibration images;
• environment determination means for determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• grayscale correction means for performing the grayscale correction, based on the on-site environmental information,
• wherein the display control means causes the image display means to display calibration images having two different grayscale values of a single color and an image that has been subjected to the grayscale correction;
• wherein the environment determination means outputs two types of the on-site environmental information in a state in which the two grayscale calibration images are displayed;
• and
• wherein the grayscale correction means performs the grayscale correction, based on a difference between two types of ideal environmental information that indicates an environment determined when the calibration images having the two grayscale values are displayed under an ideal environment and a difference between the two types of the on-site environmental information.

A computer-readable information storage medium storing a program to be used when performing grayscale correction in accordance with an on-site environment, to display an image, the program causing a computer to function as:

• display control means for causing image display means to display calibration images;
• environment determination means for determining the on-site environment in which the image display means is used and outputting on-site environmental information indicating the on-site environment;
• and
• grayscale correction means for performing the grayscale correction, based on the on-site environmental information,
• wherein the environment determination means outputs the on-site environmental information in a state in which the calibration images are displayed, and
• wherein the grayscale correction means performs gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that indicates an environment determined when the calibration images are displayed in an ideal environment and the on-site environmental information, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region.

An image processing method of performing color conversion and grayscale correction of an image in accordance with an on-site environment;

• the image processing method comprising the steps of:
• displaying calibration images for the color conversion in a plurality of colors;
• determining measured-color information of the thus-displayed calibration images for the color conversion;
• displaying calibration images for the grayscale correction that have two different grayscale values of a single color;
• determining luminance values of the thus-displayed calibration images for the grayscale correction;
• generating predetermined color conversion data, based on the thus-determined measured-color information;
• performing the color conversion of the image, based on the thus-generated color conversion data;
• and
• generating information for the grayscale correction, based on a ratio of luminance values of the two grayscale values under an ideal environment and a ratio of luminance values of the two grayscale values under the on-site environment;
• performing the grayscale correction with respect to the image that has been subjected to the color conversion, based on the thus-generated information for the grayscale correction.

An image processing method of performing color conversion and grayscale correction of an image in accordance with an on-site environment;

• the image processing method comprising the steps of:
• displaying calibration images for the grayscale correction;
• determining luminance values of the thus-displayed calibration images for the grayscale correction;
• and
• performing gamma processing for the grayscale correction, using different gamma parameters for a lower grayscale region and a higher grayscale region, based on ideal environmental information that is based on a luminance value that is determined when the calibration images are displayed under an ideal environment and on-site environmental information that is based on a luminance value that is determined when the calibration images are displayed under the on-site environment, in such a manner that a width of increase of output values is relatively greater in the lower grayscale region than in the higher grayscale region,
• wherein, where at least some of the gamma parameters are such that, constants are A and B, an output grayscale is Y, an input grayscale is X, a gamma value of the lower grayscale region is γL, and a gamma value of grayscale regions other than the lower grayscale region is γH;
• Y=AXγL is applied for the lower grayscale region, Y=BXγH is applied for the higher grayscale region, γL is a value less than 1, and γH is a value equal to or greater than 1.