Processing time reduction of tone mapping based on iterative shrinkage smoothing using parallel processing

Iterative shrinkage smoothing algorithm can perform image smoothing with eliminating fine details and preserving principal edges in an image. However, real time processing is difficult due to large processing time when input image size is large. By utilizing downscaled image of an input image, the processing time can be dramatically reduced. In this case, however, the information of preserved principal edges is not accurate. Considering the applications utilizing such edge preserving smoothing algorithms, such as image tone mapping and detail enhancement, inaccurate principal edge information degrades the quality of resulted images. In this paper, we focus on tone mapping in the applications and propose processing time reduction method of tone mapping based on iterative shrinkage smoothing by utilizing parallel processing. Experimental results show that the proposed method improves the frame rates to 16 and 10 times for VGA and full HD resolutions, respectively, compared to single process implementation.