Appearance reproduction of high-dynamic-range video based on human visual models

In this paper, we propose a method for improving image quality in order to match precisely the appearances of recorded video sequences with those of real scenes. Captured video and still images by cameras often have saturated and underexposed areas due to their limited dynamic range. Therefore, it is required to acquire images with a wide dynamic range and much tone data for the accurate reproduction of appearances. In addition, it is important to apply color reproduction processing based on human visual models to recorded videos because the appearances between the videos and real scenes differ due to the characteristics of human vision. In our method, a photometric high-dynamic-range (PHDR) video is generated by using a recorded video sequence and metadata of a camera such as the sensitivity (speed), aperture, and shutter speed. The PHDR video consists of the values of high-dynamic-range tone and absolute luminance. After the generation of a PHDR video, the video is processed by using color reproduction techniques based on spatiotemporal visual adaptation models for the accurate reproduction of appearances. Our results show that the proposed method reproduces fine appearance of videos which is the close appearance of real scenes. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 55–64, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20403