Abstract
The High dynamic range (HDR) imaging becomes more and more popular recently due to the advance of display devices. However, the acquisition of HDR images from HDR cameras is expensive for most people. The HDR inverse tone mapping (ITMO) is a technique, that maps low dynamic range (LDR) images to HDR images. Although most ITMO method can produce good HDR images, however, there are two problems in specular or light source regions of the HDR images: loss of detail and unnatural Halo effects. In this thesis, we propose a contrast enhanced expand map to reduce the over saturation problems for preserving the details information. We fuse two Gaussian maps to generate an expand map. One Gaussian map is for edge blurring, the other Gaussian map is to recover details of the specular area. We adopt a pseudo multiple exposure ITMO to generate multiple HDR images with different exposures. The darkest emulated HDR image and the expand map are used to prevent saturation and reveal the details in the specular areas. According the simulation results, our proposed method can reduce the over saturation problem and reveal details in specular areas. It also reduces the halo effects in light source areas. Comparing with Pseudo-Multiple-Exposure HDR method, the proposed method has better average values in SSIM by 1.7 ％ . The proposed method has better average values in HDR-VDP-2 75 ％ and 95 ％ by 67 ％ and 69 ％. The proposed method has better average values in mean conrast error by 62 ％.