Compressive Sensing (CS) has become one of the standard methods in face recognition due to the success of the family of Sparse Representation based Classification (SRC) algorithms. However it has been shown that in some cases, the locality of the dictionary codewords is more essential than the sparsity. Also sparse coding does not guarantee to be local which could lead to an unstable solution. We therefore consider the statistically optimal aspects of encoding that guarantee the best approximation of the query image to a dictionary that incorporates varying acquisition conditions. We focus on the investigation, analysis and experimental validation of the best robust classifier/predictor and consider frontal face image variability induced by noise, lighting, expression, pose, etc.. We compare two image representations using a pixel-wise approximation and an overcomplete block-wise approximation with two types of sparsity priors. In the first type we consider all samples from a single subject and in the second type we consider all samples from all subjects. The experiments on a publicly available dataset using low resolution images showed that several per subject sample sparsity prior approximations are as good as the results presented from SCR and that our simple overcomplete block-wise approximation provides superior performance in comparison to the SRC and WSRC algorithm.

Date Published: 19 February 2014
PDF: 15 pages
Proc. SPIE 9028, Media Watermarking, Security, and Forensics 2014, 902809 (19 February 2014); doi: 10.1117/12.2042506

Published in SPIE Proceedings Vol. 9028:
Media Watermarking, Security, and Forensics 2014
Adnan M. Alattar; Nasir D. Memon; Chad D. Heitzenrater, Editor(s)