US 2012/0056994 A1 · SINGLE-SHOT PHOTOMETRIC STEREO BY SPECTRAL MULTIPLEXING

Abstract

Single-shot photometric stereo techniques are disclosed in which chromaticity is assumed to be a variable. Scene illumination includes three or more spectrally distinct light sources. A scene image is taken with a camera system configured to measure five or more different bands, or channels, of the visible light spectrum. The light sources can include narrow-band colored LED lights, possibly combined with color filters to refine the spectral distributions. In each configuration, a beam splitter assembly is used to align two or more color cameras having different color filters placed over their lenses. By use of such techniques, a single multispectral photograph of a subject provides enough information to recover both the full-color reflectance and the surface normals on a per-pixel basis.

Claims20

Dependent claims

An image processing system for providing a simultaneous per-pixel estimate of the surface normal and full-color reflectance of an image, the system comprising:

a memory;
a processor connected to the memory;
and
programming for execution by the processor, stored in the storage device, wherein execution of the programming by the processor configures the system to perform functions, including functions to:
from intensity data from a plurality of color channels corresponding to an image illuminated by light having a plurality of spectral distributions, provide an estimate of the pixel intensity for the image for each of the plurality of color channels;
wherein the estimate of pixel intensity comprises RGB reflectance having three degrees of freedom and surface normals having two degrees of freedom;
wherein the plurality of color channels comprise five or more color channels;
and
wherein the plurality of spectral distributions comprise three or more different spectral distributions.

6 more elements

Dependencies are inferred from the claim text.

Single-shot photometric stereo by spectral multiplexing

Life of this patent

Single-shot photometric stereo by spectral multiplexing

Life of this patent

Abstract

Claims20