Subspace Clustering via Optimal Direction Search
This work addresses subspace clustering, a key problem in machine learning for applications like face recognition, by providing a robust method that handles challenging scenarios with noise and closely spaced subspaces.
The paper tackles subspace clustering by introducing a convex program for optimal direction search to identify neighborhood sets, and demonstrates that the method significantly outperforms existing approaches, especially in noisy conditions and with close subspaces, achieving state-of-the-art results in face clustering.
This letter presents a new spectral-clustering-based approach to the subspace clustering problem. Underpinning the proposed method is a convex program for optimal direction search, which for each data point d finds an optimal direction in the span of the data that has minimum projection on the other data points and non-vanishing projection on d. The obtained directions are subsequently leveraged to identify a neighborhood set for each data point. An alternating direction method of multipliers framework is provided to efficiently solve for the optimal directions. The proposed method is shown to notably outperform the existing subspace clustering methods, particularly for unwieldy scenarios involving high levels of noise and close subspaces, and yields the state-of-the-art results for the problem of face clustering using subspace segmentation.