Methods, devices and apparatus for reconstructing an image are provided. In one aspect, a method includes: determining an initial angle and a final angle of an X-ray tube and a pitch value when a helical-half-scan is to be performed, obtaining scanning data of each of reconstructing points in a reconstructing position by performing the helical-half-scan on a detected region of a subject based on the determined initial angle, the final angle and the pitch value, determining a respective half-scan-weight and a respective helical weight of each of the reconstructing points in the reconstructing position, obtaining weighted data by performing weighting on the scanning data of each of the reconstructing points with respective the half-scan-weight and the respective helical weight of the reconstructing point, and reconstructing a Computed Tomography (CT) image of the reconstructing position by performing back-projection on the weighted data.
