Fast movement detection for high dynamic range imaging

When a high dynamic range image is synthesized by using a set of differently exposed low dynamic range (LDR) images, it is important to detect moving objects so as to remove ghosting from the final HDR image. A pixel level movement detection scheme was recently proposed in [8]. It included a pixel level similarity index for differently exposed LDR images, an adaptive threshold for the classification of pixels and an approach that utilizes intensity mapping (IMF) function for patching invalid regions. In this paper, we first propose a new adaptive threshold and a new patching approach to improve the scheme in [8]. Then, a sub-sampling method is introduced to simplify the improved movement detection scheme. Experimental results show that the improved movement detection scheme indeed outperforms the scheme in [8]. In addition, the speed is significantly improved by the proposed fast movement detection scheme.