Patent ID: 7006714

Claim:
An image retrieval device for retrieving an image being similar to an inquired image from images stored in an image database comprising: a first coefficient transforming means for transforming a first group of image feature descriptors extracted from image data accumulated in said image database and then generating a second group of image feature descriptors to be used for calculating similarity, wherein said second group of image feature descriptors comprise transform coefficients obtained by performing specified coefficient transform processing on said image data accumulated in said image database; a second coefficient transforming means for transforming a first group of image feature descriptors extracted from image data of said inquired image and then generating a second group of image feature descriptors to be used for calculating similarity, wherein said second group of image feature descriptors comprise transform coefficients obtained by performing specified coefficient transform processing on said inquired image; and a similarity calculating means for calculating similarity by comparing said second group of image feature descriptors for each piece of image data generated by said first coefficient transforming means with said second group of image feature descriptors transformed by said second coefficient transforming means, wherein said first coefficient transforming means and said second coefficient transforming means perform coefficient transforms using a transform table selected depending on a kind of transform coefficient to be used as said image feature descriptor and wherein said first coefficient transforming means and said second coefficient transforming means perform retrieval of a similar image on a trial basis using a plurality of said transform tables each having a differently segmented range of said transform coefficient and select a transform table which has showed a high rate of correctly solved retrieval in said trial basis retrieval.