Content-adaptive inverse tone mapping

Abstract

Tone mapping is an important technique used for displaying high dynamic range (HDR) content on low dynamic range (LDR) devices. On the other hand, inverse tone mapping enables LDR content to appear with an HDR effect on HDR displays. The existing inverse tone mapping algorithms usually focus on enhancing the luminance in over-exposed regions with less (or even no) effort on the process of the wellexposed regions. In this paper, we propose an algorithm with not only enhancement in the over-exposed regions but also in the remaining well-exposed regions. This paper provides an ”histogram-based” method for inverse tone mapping. The proposed algorithm contains a content-adaptive inverse tone mapping operator, which has different responses with different scene characteristics. Scene classification is included in this algorithm to select the environment parameters. Lastly, enhancement of the over-exposed regions, which reconstructs the truncated information, is performed.