Estimating illumination parameters using spherical harmonics coefficients in frequency space
نویسندگان
چکیده
منابع مشابه
Estimating Illumination Parameters Using Spherical Harmonics Coefficients in Frequency Space
An algorithm is presented for estimating the direction and strength of point light with the strength of ambient illumination. Existing approaches evaluate these illumination parameters directly in the high dimensional image space, while we estimate the parameters in two steps: first by projecting the image to an orthogonal linear subspace based on spherical harmonic basis functions and then by ...
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Illumination can have a significant impact on the appearance of surfaces, as the patterns of shading, specularities and shadows change. For instance, some images of a face under different lighting conditions are shown in figure 1. Differences in lighting can often play a much greater role in image variability of human faces than differences between individual people. Lighting designers in movie...
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ژورنال
عنوان ژورنال: Tsinghua Science and Technology
سال: 2007
ISSN: 1007-0214
DOI: 10.1016/s1007-0214(07)70007-x