1) The document discusses various local feature-based methods for face recognition, including Local Binary Patterns (LBP), Local Ternary Patterns (LTP), Gabor wavelets, and Gabor Ordinal Measures (GOM).
2) LBP and Gabor wavelets are two main local feature analysis approaches that have achieved good performance in recognizing faces with variations in expression and illumination.
3) Extensions of LBP like LTP have been developed to make the features more robust to noise, especially in uniform facial regions.