A lowbit rate vocabulary coding scheme for mobile landmark search

We present a low bit rate vocabulary coding scheme in the context of mobile landmark search. Our scheme exploits location cues to boost a compact subset of visual vocabulary, which is discriminative for visual search and incurs low bit rate query for efficient upstream wireless transmission. To validate the coding scheme, we have developed mobile landmark search prototype systems within typical areas including Beijing, New York City, Lhasa, Singapore, and Florence. Our system maintains a single vocabulary in a mobile device, which can be efficiently adapted with the location information of city-scale mobile users. Thus multiple downloading of large vocabulary is completely avoided for normal city tourists. In landmark search domain, we have reported superior performance over the state-of-the art works in compact image descriptors or signatures.