Evaluation of a High Dynamic Range Video Camera with a Non-Regular Sensor

Although there is steady progress in sensor technology, imaging with a high dynamic range (HDR) is still difficult for motion imaging with high image quality. This paper presents our new approach for video acquisition with high dynamic range. The principle is based on optical attenuation of some of the pixels of an existing image sensor. This well known method traditionally trades spatial resolution for an increase in dynamic range. In contrast to existing work, we use a non-regular pattern of optical ND filters for attenuation. This allows for an image reconstruction that is able to recover high resolution images. The reconstruction is based on the assumption that natural images can be represented nearly sparse in transform domains, which allows for recovery of scenes with high detail. The proposed combination of non-regular sampling and image reconstruction leads to a system with an increase in dynamic range without sacrificing spatial resolution. In this paper, a further evaluation is presented on the achievable image quality. In our prototype we found that crosstalk is present and significant. The discussion thus shows the limits of the proposed imaging system.