Research Article

An Improved EMD-Based Dissimilarity Metric for Unsupervised Linear Subspace Learning

Algorithm 1

The improved EMD metric for LPP.
Input: the sample set with samples, parameter , block parameter , pHOG bins, nearest neighbors parameter
Output: adjacency graph , weight matrix , transformation matrix , eigenvalues , and subspace y
Whileā€‰ā€‰
Extract HOG histogram over each block of per face image
Carry out the pooling operation over each block and then get the pHOG histogram
Obtain the grids of pHOG vector for one face image and grids of pHOG vectors for the rest of face images ,
Compute the dissimilarity between and by Equations (8) and (9)
Obtain the nearest neighbors of the face image :
EndWhile
Build the adjacency graph and calculate the corresponding weight matrix by Equation (10)
Begin // compute the projection
Get the diagonal matrix
Solve the generalized eigenvector problem of Equation (11) on the sample set
Get the eigenvectors with respect to eigenvalues
End // compute the projection
Obtain the transformation matrix
Obtain the subspace for the sample set by Equation (13)
(16) Perform face recognition by the classifier