An image signal digitization method, an image signal restoration method, and an image signal encoding method, an image signal decoding method, a recording medium recording the program and image signal digitization program, the program is recorded and an image signal restoration program a recording medium which has a recording medium recording the program and the picture signal encoding program recording medium storing the program and the picture signal decoding program

摘要

PPROBLEM TO BE SOLVED: To provide an image processing technique for efficiently quantizing image signals represented with gray scales or a three-dimensional color space into digital signals. PSOLUTION: The method comprises transforming image signals represented with a gray scale or a three-dimensional color space in a uniform color space, uniformly quantizing the image signals about each axis, and converting quantized values in a digital representation, based on a designated minimum lattice spacing. It comprises transforming image signals represented with a three-dimensional color space in a brightness-color difference separation type uniform color space, uniformly quantizing the image signals about the brightness axis based on the designated minimum lattice spacing, quantizing the image signals about the color difference plane based on a triangle lattice, and converting the quantized values in a digital representation. It also comprises transforming image signals represented with a three-dimensional color space in a uniform color space, quantizing the image signals based on a face-centered cubic lattice-hexagonal closed packed lattice with the designated minimum lattice spacing, and converting the quantized values in a digital representation. PCOPYRIGHT: (C)2004,JPO