Noise characterization of weighting schemes for combination of multiple exposures

A method for capturing high intensity dynamic range scenes with a low dynamic range camera consists in taking a series of images with di erent exposure settings and combining these into a single high dynamic range image. The combined image values are found by weighted averaging of values from the di erently exposed images on a per-pixel basis. This paper reviews existing weighting schemes and considers their noise properties. Furthermore, a minimum-variance solution is introduced which exploits a camera noise model. Special emphasis is on the case when the camera is linear. A method is given for estimating the uncertainty of the combined image values. The results are validated experimentally. 1