Sparse Representation Based Projections
Radu Timofte, Luc Van Gool · 2011
In dimensionality reduction most methods aim at preserving one or a few properties of the original space in the resulting embedding.As our results show, preserving the sparse representation of the signals from the original space in the (lower) dimensional projected space is beneficial for several benchmarks (faces, traffic signs, and handwritten digits).The intuition behind is that taking a sparse representation for the different samples as point of departure highlights the important correlations among the samples that one then wants to exploit to arrive at the final, effective low-dimensional embedding.We explicitly adapt the LPP and LLE techniques to work with the sparse representation criterion and compare to the original methods on the referenced databases, and this for both unsupervised and supervised cases.The improved results corroborate the usefulness of the proposed sparse representation based linear and non-linear projections.