We propose an interactive system for identifying flags in photos taken from natural scenes. The system is interactive in two respects. First, because segmentation can be a difficult problem, users are asked to crop the flag portion from a photo. Second, the user makes the final decision by selecting one of the top choices obtained from the machine classification system. The proposed system utilizes a color-based image retrieval technique. For experimental purposes a large number of flag images are synthetically generated from a small number of original ones in order to increase the reference image database. A nearest neighbor classifier produces a sorted list of candidate choices. Recognition accuracy of these choices varies from 82% to 93% depending on whether the correct flag is among the first 8 or 18 top choices, respectively, from a set of 186 flags.
Hart, Eduardo; Cha, Sung-Hyuk; and Tappert, Charles C., "Interactive Flag Identification" (2004). CSIS Technical Reports. Paper 17.