Techniques for object appearance capture

Abstract

Techniques are disclosed for capturing facial appearance properties. In some examples, a facial capture system includes light source(s) that produce linearly polarized light, at least one camera that is cross-polarized with respect to the polarization of light produced by the light source(s), and at least one other camera that is not cross-polarized with respect to the polarization of the light produced by the light source(s). Images captured by the cross-polarized camera(s) are used to determine facial appearance properties other than specular intensity, such as diffuse albedo, while images captured by the camera(s) that are not cross-polarized are used to determine facial appearance properties including specular intensity. In addition, a coarse-to-fine optimization procedure is disclosed for determining appearance and detailed geometry maps based on images captured by the cross-polarized camera(s) and the camera(s) that are not cross-polarized.

Description

BACKGROUNDTechnical Field[0001]Embodiments of the present disclosure relate generally to computer science and computer graphics and, more specifically, to techniques for facial appearance capture.Description of the Related Art[0002]Realistic digital faces are required for various computer graphics and computer vision applications. For example, digital faces are oftentimes used in virtual scenes of film or television productions and in video games.[0003]A digital face can be synthesized using three-dimensional (3D) geometry of the face and two-dimensional (2D) appearance maps indicating reflectance properties of the face. As used herein, “appearance” refers to reflectance properties characterizing how light interacts with materials before reaching a camera. Example reflectance properties include, without limitation, shininess (also referred to as “specular intensity”) and the shape of a specular reflection lobe (also referred to as “roughness”), which are surface properties of skin, ...

AI Technical Summary

Benefits of technology

[0010]At least one technical advantage of the disclosed techniques relative to the prior art is that the disclosed techniques can be used to generate high-quality appearance maps and detailed geometry maps, without requiring the specialized light stages and hundreds of lights typically associated with conventional facial capture systems. As a result, the disclosed technique provide ease of use and increased practical applicability relative to conventional facial capture systems. The disclosed techniques also permit single-shot capture, as opposed to multi-shot capture with strobed lighting, which reduces the discomfort to individuals whose faces are being captured. In addition, the disclosed techniques permit dynamic facial capture from videos. These technical advantages represent one or more technological improvements over prior art approaches.

Problems solved by technology

One drawback of the above approach to capturing images of individual faces to create appearance maps is that the facial capture systems are complex and not portable, which limits the practical applicability of those systems.

Another drawback is that strobing the lights of a facial capture system through different illumination conditions can be uncomfortable to the individual whose face is being captured.

Further, using motion compensation techniques to compensate for the movements of an individual can reduce the overall quality of the facial capture results.

In addition, typical facial capture systems permit only static facial capture, not dynamic facial capture from videos.

Images