Patent ID: 8447120

Claim:
In a computing environment, a method comprising: receiving new images at an image retrieval system, and incrementally updating a vocabulary tree model structure, having a parent node with one or more child leaf nodes, based upon the new images using a computer processor, including iteratively refining the model structure to fit a new data distribution based on the new images, wherein iteratively refining comprises: updating a given one of the child leaf nodes based upon words corresponding to the new images; evaluating feature frequencies of the given updated child leaf node against a threshold value; and processing the updated child leaf node based on the evaluation, wherein processing comprises determining that the updated child leaf node has a feature frequency that is below the threshold value and that the updated child leaf node has at least one sibling leaf node and, in response to the determination, deleting the updated child leaf node and assigning features of the updated child leaf node to one or more of the at least one sibling leaf node.