Validation of image analysis techniques to measure skin aging features from facial photographs. - Hamer MA; Jacobs LC; Lall JS; Wollstein A; Hollestein LM; Rae AR; Gossage KW; Hofman A; Liu F; Kayser M; Nijsten T; Gunn DA (Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI), 2015)