Figure 15From: SHERPA: an image segmentation and outline feature extraction tool for diatoms and other objectsPrincipal component analysis of elliptic Fourier descriptor invariants for the Sellaphora data set. EFDIs have a comparable discriminatory power to the Legendre polynomials used by Mann et al. [7], differentiating the three main shape groups but not the individual demes/species within each shape group.Back to article page