The paper describes a robust method for estimating, in a reliable manner, the illumination distribution of a real scene from shadows in a given image. In general, shadows in a scene are caused by the occlusion of incoming light; image brightness inside shadows have great potential for providing distinct clues to the illumination distribution of the scene. Taking advantage of this fact, we recently proposed to estimate the illumination distribution of a real scene from a single image of the scene. The proposed method has been applied successfully to real images with complex illumination distributions. Nevertheless, it was found that sometimes the method failed to provide a correct estimate of illumination distribution. Those failures stem from the fact that the method does not take into account several factors regarding the stability of illumination estimation. The study analyzes how much information is obtainable from a given image about the illumination distribution of the scene. In particular, we carefully examine the source of instability of using shadows obtained from a single image for the estimation in several aspects: blocked view of shadows by the object; limited sampling resolution for image brightness inside shadows; and the appropriate light model to approximate the illumination distribution of the scene. Based on this analysis, we propose a method that guarantees to reliably estimate the illumination distribution of a scene, regardless of the type of input image.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Stability issues in recovering illumination distribution from brightness in shadows


    Contributors:
    Sato, I. (author) / Sato, Y. (author) / Ikeuchi, K. (author)


    Publication date :

    2001-01-01


    Size :

    1252253 byte





    Type of media :

    Conference paper


    Type of material :

    Electronic Resource


    Language :

    English



    Stability Issues in Recovering Illumination Distribution from Brightness in Shadows

    Sato, I. / Sato, Y. / Ikeuchi, K. et al. | British Library Conference Proceedings | 2001


    Spherical Harmonics vs. Haar Wavelets: Basis for Recovering Illumination from Cast Shadows

    Okabe, T. / Sato, I. / Sato, Y. et al. | British Library Conference Proceedings | 2004



    A Practical Single Image Based Approach for Estimating Illumination Distribution from Shadows

    Kim, T. / Hong, K.-S. / IEEE | British Library Conference Proceedings | 2005