Ghosting-free multi-exposure image fusion in gradient domain

This paper presents an algorithm to produce ghosting-free High Dynamic Range (HDR) image by fusing set of multiple exposed images in gradient domain. Recently proposed Gradient domain based exposure fusion method provides high quality result but the scope of which is limited to static camera without foreground object motion. The presence of moving objects/hand shake produces a set of misaligned images. The result of gradient domain approach on misaligned images suffers from ghosting artifacts. In order to produce better HDR image without image registration, we propose to create an aligned image set from input image set by photometric calibration. The gradient of aligned image set is then used to reconstruct the fused final image. The proposed algorithm tested on several publicly available dynamic image sets shows that resultant HDR image is ghosting-free and well exposed. Additionally, the proposed method is fast and thus can be used in consumer appliances such as mobile phones, portable devices with digital cameras.