US 7,031,510 B2 · Region segmentation of color image

Abstract

A color image of a circuit board is divided into respective color regions. Plural representative colors are set, and angle indices and distance indices are calculated for each pixel color in the color image in a predetermined color space. The angle indices for a particular pixel color represent angles between an individual color vector representing the particular pixel color and plural representative color vectors of the plural representative colors. The distance indices for a particular pixel color represent distances between the particular pixel color and the plural representative colors. Composite distance indices are then calculated for each pixel color in the color image, based on the distance indices and the angle indices. Each pixel in the color image is classified into plural representative color regions associated with the plural representative colors according to the composite distance indices, thereby dividing the image region of the color image into the plural representative color regions.

Claims20

Dependent claims

A method for dividing an image region of a color image according to colors, comprising the steps of:

(a) setting a plurality of representative colors;
(b) calculating plural angle indices for each pixel color in the color image, the plural angle indices for a pixel color representing angles between an individual color vector of the pixel color and representative color vectors of the plurality of representative color vectors in a predetermined color space of at least two dimensions;
(c) calculating plural distance indices for each pixel color in the color image, the plural distance indices for a pixel color representing distances between the pixel color and the plural representative colors in the color space;
(d) calculating plural composite distance indices for each pixel color in the color image based on the distance indices and the angle indices, the plural composite distance indices being associated with the plurality of representative colors, respectively;
and
(e) classifying pixels in the color image into plural representative color regions associated with the plural representative colors, according to the composite distance indices, thereby dividing the image region of the color image into the plural representative color regions.

3 more elements

A method for dividing an image region of a color image according to colors, comprising the steps of:

(a) setting a plurality of representative colors;
(b) calculating plural angle indices for each arbitrary individual color in the color space, the angle indices for an arbitrary individual color representing angles between an individual color vector of the arbitrary individual color and representative color vectors of the plurality of representative colors in a predetermined color space of at least two dimensions;
(c) calculating distance indices for each arbitrary individual color in the color space, the distance indices for an arbitrary individual color representing distances between the arbitrary individual color and the plural representative colors in the color space;
(d) calculating composite distance indices for each arbitrary individual color in the color space based on the distance indices and the angle indices, the plural composite distance indices being associated with the plurality of representative colors, respectively;
(e) relating each arbitrary individual color in the color space with one of the plural representative colors according to the composite distance indices, and preparing a lookup table storing the correspondence between each arbitrary individual color and the plural representative colors;
and
(f) classifying pixels in the color image into plural representative color regions associated with the plural representative colors, with the aid of the lookup table, thereby dividing the image region of the color image into the plural representative color regions.

4 more elements

A method for inspecting a circuit board, comprising the steps of:

(a) setting a plurality of representative colors;
(b) calculating plural angle indices for each arbitrary individual color in the color space, the angle indices for an arbitrary individual color representing angles between an individual color vector of the arbitrary individual color and representative color vectors of the plurality of representative colors in a predetermined color space of at least two dimensions;
(c) calculating distance indices for each arbitrary individual color in the color space, the distance indices for an arbitrary individual color representing distances between the arbitrary individual color and the plural representative colors in the color space;
(d) calculating composite distance indices for each arbitrary individual color in the color space based on the distance indices and the angle indices, the plural composite distance indices being associated with the plurality of representative colors, respectively;
(e) relating each arbitrary individual color in the color space with one of the plural representative colors according to the composite distance indices, and preparing a lookup table storing the correspondence between each arbitrary individual color and the plural representative colors;
(f) capturing a color image of the circuit board;
(g) classifying pixels in the color image into plural representative color regions associated with the plural representative colors, with the aid of the lookup table, thereby dividing an image region of the color image into the plural representative color regions;
and
(h) performing inspection of the circuit board using at least one of the divided plural representative color regions.

6 more elements

Dependencies are inferred from the claim text.

Region segmentation of color image

Life of this patent

Region segmentation of color image

Life of this patent

Abstract

Claims20