Estimating a surface area and/or volume of a body or a body part of a subject

According to an aspect, there is provided a computer-implemented method for estimating a surface area and/or a volume of a body or a body part of a subject. The method comprises obtaining at least one image, wherein the at least one image includes a face of the subject; processing the at least one image to determine values for one or more facial image parameters for the face of the subject; determining values for one or more characteristics of the subject, wherein the one or more characteristics comprises one or more of age of the subject, weight of the subject, height of the subject and gender of the subject; using a facial parametric model and the determined values for the one or more facial image parameters to determine values for one or more facial shape parameters for the face of the subject, wherein the facial parametric model relates specific values for one or more facial image parameters to a respective 3D representation of a face having respective values for the one or more facial shape parameters; using a prediction model with the determined values for the one or more characteristics and the determined values of the one or more facial shape parameters to predict a 3D representation of the full body of the subject; and analyzing the predicted 3D representation of the full body of the subject to estimate the surface area and/or the volume of the body or body part of the subject. A corresponding apparatus and computer program product is also provided.</p