Image retrieval method and apparatus independent of illumination change

An image retrieval apparatus independent of illumination changes comprising:

• a query image input unit which receives a query image;
• a standard illumination color converting unit which detects an illumination color from the query image and converts the illumination color into a standard illumination color;
• a query image color information extracting unit which extracts color information of the converted query image by using color descriptors;
• a database which converts a variety of images desired to be retrieved into images of standard illumination colors and extracts and stores the color information of the images in advance;
• and
• a similar image retrieval unit which finds a similar image by comparing the color information of the query image that is converted into an image of the standard illumination color, with color information on the variety of images stored in the database.

A standard illumination color converting method comprising:

• removing low luminance parts and self luminance parts from an input query image;
• detecting an illumination color of the image from the remaining pixels after the removal of the low luminance parts and self luminance parts;
• and
• converting the detected illumination color into a standard illumination color.