Abstract: A method for extracting a three-dimensional color vector from a three-dimensional color space in which correlated features are distributed includes steps of projecting the three-dimensional color space on a two-dimensional plane, displaying the two-dimensional plane on a display screen of a display, designating a line segment on the display screen by an input device, and executing the above steps at least two times by changing the angle of projection between the three-dimensional space and the two-dimensional plane to extract the color vector.

Abstract: Simultaneously and automatically with creating a CG image by computer graphics, (1) the image is segmented to create a mask image, (2) a mask attribute table is created by data transformation, (3) an intrinsic image (object color component, light source color component, ambient color component) is created by data transformation, and the results are saved. The mask image is used to cut a portion from the computer graphics image and the cut portion is combined with a different image, which may be a natural image for example, to obtain a composite image, and at the same time, transparency processing or other such image processing is conducted on the basis of the attribute data. In addition, the color etc. of the object are modified by changing the object color vector or the like.

Abstract: A function of simulating change of weather and time in one scene by changing a sky area and an object area in a natural image while maintaining a relationship therebetween. The natural image is separated into a sky area and an object area excluding the sky area. The color of the object area is generated from a reflection model of the object, based on the color of sunlight, the color of a sky light, and a reflectance of the object. The sky light is determined by averaging pixel values of the sky area. The color of the sky light can be determined based on the color of the sunlight and meteorological conditions such as clouds and fog. The color of the sunlight, the meteorological conditions and the color of the sky light can be determined by specifying parameters representing time and weather. By changing the parameters, a simulation for changing the time and the weather can be performed on the entire natural image.

Abstract: A first image is inputted, and an object area for mapping is determined on the first image. Transformation parameters for the mapping are calculated pixel by pixel from the attributes of the first image in the object area, a second image to be mapped into at least one part of the object area is generated, and the second image is mapped pixel by pixel in the object area of the first image operating the transformation parameters so as to generate a third image. When an image simulation for changing the color and texture in an area of a color or monochromatic gray scale image is performed, an image simulation for ignoring effects of fine texture on the initial image and reflecting the shadow and shade can be realized.

Abstract: In order to accomplish a color adjustment capable of determining a color at a high degree of freedom, a variety of color expressions and corresponding input instructions are correlated to reflect the instruction of a color change by a certain expression upon another expression. In order to accomplish a color change considering the changes in the ambience, moreover, each vector of an object color, a light source color, a color texture, an ambient color and an input bias is decided to determine the separated component values of the former three vectors of a picture element value so that the changed color of the picture element value may be determined after the vector change from the separated component values and the changed vectors.