摘要
An effective method for object shape recovery using HDRIs （high dynamic range images） is proposed. The radiance values of each point on the reference sphere and target object are firstly calculated, thus the set of candidate normals of each target point are found by comparing its radiance to that of each reference sphere point. In single-image shape recovery, a smoothness operation is applied to the target normals to obtain a stable and reasonable result; while in photometric stereo, radiance vectors of reference and target objects formed due to illuminations under different fight source directions are directly compared to get the most suitable target normals. Finally, the height values can be recovered from the resulting normal field. Because diffuse and specular reflection are handled in an unified framework with radiance, our approach eliminates the limitation presented in most recovery strategies, i.e., only Lambertian model can be used. The experiment results from the real and synthesized images show the performance of our approach.
An effective method for object shape recovery using HDRIs (high dynamic range images) is pro-posed.The radiance values of each point on the reference sphere and target object are firstly calculated,thus the set of candidate normals of each target point are found by comparing its radiance to that of eachreference sphere point.In single-image shape recovery,a smoothness operation is applied to the targetnonnals to obtain a stable and reasonable result;while in photometric stereo,radiance vectors of refer-ence and target objeets formed due to illuminations under different light source direetions are directly com-pared to get the most suitable target normals.Finally,the height values ean be recovered from the result-ing normal field.Because diffuse and specular refleetion are handled in an unified framework with radi-ance,our approach eliminates the limitation presented in most reeovery strategies,i.e.,only Lambertianmodel can be used.The experiment results from the real and synthesized images show the performance ofour approach.
基金
the National Basic Research Program of China(No.2006CB303105)
