Proceedings: GI 2013

Non-linear normalized entropy based exposure blending

Neil Bruce

Proceedings of Graphics Interface 2013: Regina, Saskatchewan, Canada, 29 - 31 May 2013, 37-44

DOI 10.20380/GI2013.06

  • Bibtex

    author = {Bruce, Neil},
    title = {Non-linear normalized entropy based exposure blending},
    booktitle = {Proceedings of Graphics Interface 2013},
    series = {GI 2013},
    year = {2013},
    issn = {0713-5424},
    isbn = {978-1-4822-1680-6},
    location = {Regina, Saskatchewan, Canada},
    pages = {37--44},
    numpages = {8},
    doi = {10.20380/GI2013.06},
    publisher = {Canadian Human-Computer Communications Society},
    address = {Toronto, Ontario, Canada},


In this paper we consider the problem of dynamic range compression from multiple exposures in the absence of raw images, radiometric response functions, or irradiance information. This is achieved in a rapid and relatively simplistic fashion by merging image content across provided exposures. The premise of the proposal lies in assuming as one important goal of tone-mapping, that of making visible any contrast appearing across a dynamic range that exceeds display capabilities, while preserving the nature of the image structure, lighting, and avoiding introducing discontinuities in illumination, or image artifacts. The strategy assumed for this purpose appeals to the local entropy evident in each exposure, and employs cross-exposure normalization of entropy with a non-linearity characterized by a single parameter providing a trade-off between detail, and smoothness of the result.