Retinex preprocessing of uncalibrated images for color based image retrieval

In image databases, variations in imaging conditions and preprocessing may result in similar originals that exhibit a low measure of similarity when color information is used in standard image retrieval methods. We examine the performance of various color-based retrieval strategies to see whether, and to what degree, the effectiveness of retrieval improves with Retinex-based preprocessing, regardless of the strategy adopted. The results of experiments performed on four different databases are reported and discussed.