A three-dimensional shape parameter computation system and method for computing three-dimensional human head shape parameters from two-dimensional facial feature points. A series of images containing a user's face is captured. Embodiments of the system and method deduce the 3D parameters of the user's head by examining a series of captured images of the user over time and in a variety of head poses and facial expressions, and then computing an average. An energy function is constructed over a batch of frames containing 2D face feature points obtained from the captured images, and the energy function is minimized to solve for the head shape parameters valid for the batch of frames. Head pose parameters and facial expression and animation parameters can vary over each captured image in the batch of frames. In some embodiments this minimization is performed using a modified Gauss-Newton minimization technique using a single iteration.