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This paper presents a novel wide dynamic range system to reduce flickering artifact produced by a high speed electronic rolling shutter in a CMOS image sensor. The proposed algorithm removes flicker artifact in the shortexposure image using a correlation between the pair of two differently exposed images to extend the dynamic range. Since the proposed method overcomes the electronic shutter problem in a conventional wide dynamic range imaging system, it can remove the flicker artifact under an alternating current light source such as a fluorescent bulb.

In this paper, we present a novel high dynamic range (HDR) imaging method using a single image. The existing multiple image-based HDR methods work only on condition that there is no camera and object movement when acquiring multiple, differently exposed low dynamic range (LDR) images. To overcome such an unrealistic restriction, we make three LDR images from a single input image using local histogram stretching. An edge-preserving spatially adaptive denoising method is also proposed to suppress the noise that is amplified in the histogram stretching process. Because the proposed method self-generates three histogram-stretched LDR images from a single input image, ghost artifacts that are the result of the relative motion between the camera and objects during exposure time, are inherently removed. Therefore, the proposed method can be applied to mobile imaging devices such as a mobile phone camera and a consumer compact camera to provide the ghost artifacts free HDR function in the form of either embedded or post-processing software.

In this paper, we present a ghost artifacts removing method for obtaining artifact-free high dynamic range (HDR) images in the presence of camera movement. The existing HDR methods work on condition that there is no camera movement when acquiring multiple low dynamic range (LDR) images. For overcoming such unrealistic restriction, we register the multiple LDR images by using a novel target frame finding method. Ghost artifacts are removed in the resulting HDR images since the registration process of LDR images compensates undesired camera motion. Since the proposed method can embed the self compensating function into an imaging device, Ghost-free HDR imaging application can be extended to most consumer cameras, such as mobile phone cameras, point-and-shoot cameras, and digital single lens reflected (DSLR) cameras without using additional stabilizing equipments.