Combination of histogram of oriented gradients and hierarchical centroid for sketch-based image retrieval

The sketch based image retrieval (SBIR) systems is still little argued and debated. Histogram of oriented gradients (HOG) has shown good performance in sketch based retrieval systems over all other methods. In this paper, we propose an enhancement of HOG by using HOG combined with hierarchical centroid of irregular shape. We also compare the result with original HOG, edge histogram and the shape properties descriptors. The system uses free-hand sketched queries as input and matches it with images from different 12 classes.