“…Early attempts applied low/medium level global features, including graphic feature vectors [27], Fourier descriptors [16,21,66], image moments [12,16,22,66], Zernike moments [29,63,70] as well as simpler and lower-cost shape features such as aspect ratio [16], circularity [16], Rosin descriptor [16], angular radial transform [16], gray level projection [66], gradient orientation histogram [12,22], wavelets [12], triangle area representation [2,3] -see Table 1 for an overview. In addition to shape and texture related features, color-feature based approaches have also been applied for trademark retrieval [32,45,48,50,69].…”