The present disclosure relates to a method and a system for computer tomography imaging. The method may comprise obtaining original data obtaining a preprocessing result by preprocessing the original data obtaining intensity of the artifact based on the preprocessing result and updating a damaged channel or the air correction table based on the intensity of the artifact. Updating the air correction table may comprise: obtaining a first air correction table corresponding to a first temperature of detector obtaining real-time temperature of detector and obtaining a second air correction table corresponding to the real-time temperature based on the real-time temperature and the first air correction table.
