Subjective evaluation of tone-mapping methods on 3D images

Abstract

High dynamic range (HDR) imaging provides superior picture quality to traditional 8 bit, low dynamic range (LDR), image representations. Capturing images/videos in HDR format can avoid problems with over and under exposures. Tone-mapping is a process that converts from HDR to LDR, so that HDR content can be shown on existing displays. Tone mapping has been extensively studied in the context of 2D images/video but not for 3D content. This paper addresses the problem of presenting 3D HDR content on stereoscopic LDR displays and presents a subjective psychophysical experiment that evaluates existing tone-mapping operators on 3D HDR images. The results show that 3D content derived using tone-mapping is much preferred to that is captured directly with a pair of LDR cameras. Global tone-mapping methods (which better preserve global contrast) are found to produce images with better 3D effect than local tone-mapping operators (which produce images with high amounts of detail/texture). Also, the brightness of the tone-mapped images is found to be highly collated with perceived 3D quality.