Clustering Based Local Tone Mapping Algorithm for Displaying HDR Images on LDR Devices

摘要

In order to display HDR (High Dynamic Range) images with increased dynamic range on LDR(Low Dynamic Range) monitors, it is necessary to perform a tone mapping technique, which is aprocess of compressing a dynamic range of an image. Representative techniques are global tonemapping and local tone mapping. Though global tone mapping is simple to compute, it has lowlocal contrast and loses details. Local tone mapping has high local contrast but it demands highcomputational complexity. In order to take advantage and to compensate of two techniques, wepropose local tone mapping based on clustering. Clustering reduces the complexity of local tonemapping implementation by dividing images. In the local tone mapping process, the localadaptation is obtained by combining the cluster-level log mean and global log mean. Usinglocal characteristics, that is local adaptation, based on clustering, the results has high localcontrasts and local detail is improved. Experiment result shows that proposed algorithm hasbetter performance than conventional algorithm.