Single-image specular reflection separation

摘要

Systems and methods are discussed to separate the specular reflectivity and/or the diffuse reflectivity from an input image. Embodiments of the invention can be used to determine the specular chromaticity by iteratively solving one or more objective functions. An objective function can include functions that take into account the smooth gradient of the specular chromaticity. An objective function can take into account the interior chromatic homogeneity of the diffuse chromaticity and/or the sharp changes between chromaticity. Embodiments of the invention can also be used to determine the specular chromaticity of an image using a pseudo specular-free image that is calculated from the input image and a dark channel image that can be used to iteratively solve an objective function(s).

主权项

1. A method for providing a specular reflectivity from an input image comprising:
receiving the input image at a computer device, wherein the input image comprises a red channel, a green channel, and a blue channel for each pixel in the input image; computing a cluster analysis on the input image that clusters each pixel in the input image into clusters having similar chromaticity, wherein the cluster analysis determines a chromaticity index for each pixel and a chromaticity vector that indicates an average chromaticity of each cluster represented by the chromaticity index; determining, from an objective function, the specular reflectivity of the input image, wherein the objective function includes a function that specifies that the specular reflectivity is smooth across edges within the input image, and wherein the objective function additionally specifies that a diffuse reflectivity either i) is relatively constant within each cluster or ii) changes sharply between clusters; and providing the specular reflectivity of the input image.