1. A method of destreaking the photoelectric image in multi-energy X-ray computed tomography, wherein a set of photoelectric projections is provided, wherein a neighboring scheme is also provided, for each photoelectric projection data point, comprising: A. Computing the mean and the standard deviation of the neighbors defined by the neighboring scheme; B. Calculating an upper limit and a lower limit from the computed mean and standard deviation; C. Detecting an outlier using the calculated upper and lower limits; and D. Replacing the detected outliers with replacements.