Patent ID: 8064685

Claim:
A method for object recognition of a three dimensional (3D) object, the method comprising at an electronic device, maintaining a statistical 3D-shape model used to express 3D-shapes of object features in terms of a median 3D-shape, μ, and a base of 3D-shapes, W, where each 3D-shape, t 3D (i), is expressed in terms of an associated latent characteristic, u(i), as t 3D (i)=W*u(i)+μ, where 3D-shape vectors t 3D and μ are d-dimensional, a matrix of the base of 3D-shapes is (d×q)-dimensional, and latent characteristic vectors u are q-dimensional, and where the object features include points, lines and contours corresponding to objects of an object class; accessing a profile corresponding to at least a known object of the object class, the profile stored on persistent storage communicatively coupled with the electronic device, the profile including a latent characteristic, u(k), associated with a 3D-shape, t 3D (k), of the known object, in accordance with the statistical 3D-shape model, t 3D (k)=W*u(k)+μ; detecting, by the electronic device, object features, t 2D (o), of an object depicted in a two dimensional (2D) image, where a vector, t 2D , representing representation of said detected object features is e-dimensional; determining, by the electronic device, a 3D-shape, t 3D (o), corresponding to the detected object features, t 2D (o), such that a projection model f(t 3D ) applied to the determined 3D-shape, t 3D (o), results in the detected object features t 2D (o)=f[t 3D (o)], said determining the 3D-shape, t 3D (o), comprising: optimizing the projection model, f[t 3D (i)], applied to 3D-shapes, t 3D (i), expressed in terms of respective latent characteristics, u(i), in accordance with the statistical 3D-shape model, t 3D (i)=W*u(i)+μ, said optimizing over the respective latent characteristics u(i), and selecting a latent characteristic u(o) corresponding to the optimized projection model, f[t 3D (o)], such that the optimized projection model applied to a 3D shape expressed in terms of the selected latent characteristic, u(o), results in the detected object features t 2D (o)=f[W*u(o)+μ)], where the 3D-shape expressed in terms of the selected latent characteristic, u(o), represents the determined 3D-shape, t 3D (o); comparing, by the electronic device, the selected latent characteristic u(o), corresponding to the detected object features, t 2D (o), at least with the latent characteristic included in the stored profile, u(k), and associated with the 3D-shape, t 3D (k), of the known object; selectively recognizing the object depicted in the 2D image as the known object based on said comparing.