An improved image retrieval process based on relevance feedback uses a
hierarchical (per-feature) approach in comparing images. Multiple query
vectors are generated for an initial image by extracting multiple
low-level features from the initial image. When determining how closely a
particular image in an image collection matches the initial image, a
distance is calculated between the query vectors and corresponding
low-level feature vectors extracted from the particular image. Once these
individual distances are calculated, they are combined to generate an
overall distance that represents how closely the two images match.
According to other aspects, relevancy feedback received regarding
previously retrieved images is used during the query vector generation
and the distance determination to influence which images are subsequently
retrieved.
