http://vis-www.cs.umass.edu/lfw/。 Mingming Gong told me about this database. Qi Li did experiments using this database in his 20130625 report. In Qi Li's 20130625 report and his ACPR paper, why 175 images? He used the data set:  http://perception.csl.illinois.edu/matrix-rank/rasl.html. He just selected 5 persons due to speed. Which people did he choose? The sample images give the answer, such as George_W_Bush. He says he randomly selects and maybe the experimental results do not differ too much.
" LFW库学习记录.docx"见电脑本机目录:Robust Face Recognition via Sparse Representation\RASL\RASL_Code\data\LFW库学习记录.docx