Our method relies on high level visual landmarks consisting of appearance invariant descriptors that are extracted by a pre-trained Convolutional Neural Network (CNN) on the basis of image patches.
One approach is to use a suitable set of landmarks consisting of noticeable facial parts such as the eyes, nose, and mouth as well as the relative locations and the statistics of local neighboring pixels of these landmarks to construct feature vectors containing relevant and nonredundant information [8, 9].
Twenty-four homolandmarksndmarks, consisting of 12 fixed and 12 semi-landmarks were defined that describe the external LPJ shape along with the dentigerous area (Additional file 1: Figure S1).
These landmarks, consisting of the central sulcus, sylvian fissure, anterior portion of the superior temporal gyrus, calcarine sulcus, and dorsal and ventral portions of the medial wall, were drawn on smoothed or flattened surfaces using information visible in other surface configurations (midthickness, inflated) as well as the segmentation and MRI volumes.
These landmarks consist of a reduced set of key points, obtained automatically as in [6]. Figure 6 shows an example of the situation of these 14 points.
Landmarks consisted of boundaries or points that were considered homologous across Rhabditina as predicted by fine-structural anatomy (Baldwin et al., 1997; Ragsdale and Baldwin, 2010); stomatal terminology follows De Ley et al. (1995).
For this study, the definition of the Rv coefficient was the correlation between two landmarks each consisting of x and y variables in two dimensions (for more general explanations, see references [ 86- 90]).
Generalised Procrustes Analysis (GPA) was performed on landmark configurations (each consisting of 63 x, y and z coordinates of 21 facial landmarks) in order to remove differences in landmark positions attributable to translation and rotation.
The Old Man of the Mountain, a landmark on Cannon Mountain consisting of a rock outcropping that resembled a human face, collapsed in 2003.
Landmark initialization consists of defining the initial coordinates and the initial covariance of landmarks (interest points).
