Dictionary Learning Based on Nonnegative Matrix Factorization Using Parallel Coordinate Descent

Figure 10

Globally featured faces learned by SNMF, NMFSC, NMFℓ⁰-H, and PCDDL.

(a) SNMF  

(b) NMFSC

(c) NMFℓ⁰-H

(d) PCDDL