Face 3D
WHAT IS FACE 3D?
From user’s point of view, Face 3D is simply a box, into which you may pass an image of one’s face, or a few of them, and get a 3D model of the face.
HOW IT WORKS?
Face 3D has a set of vectors, representing different facial shapes, iånside. We call this set a Morphable model. Points in these vectors are arranged in such a way that semantically identical points of different faces have the same coordinate indices. For example, if tip of the nose in model s1 is on the first position then tips of the nose in all the other models s2, …,sk are also on the first positions.
Shapes of all other faces are assumed to be linear combinations of those, comprised in our Morphable model. Thus, given a set of input images, Face 3D determines a linear combination which best matches to them. In order to do so, it also has to recover rotation and illumination of the face for each input image.
BUILDING A MORPHABLE MODEL
Although, facial shape recovery on the base of a Morphable model requires much effort, a Morphable model construction is a tough problem itself, since one has to establish correspondence between semantically identical points of the models. Moreover, input models contain different number of points making the task even more difficult. Furthermore, input models are not textured, so point correspondence has to be recovered taking into account facial shape only.
We’ve managed to overcome all the mentioned challenges and built such a Morphable model by reducing the problem to motion field recovery task applying some reasonable point-wise similarity function. This task is formulated as a MaxSum labeling problem.
SEE IT IN ACTION
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