Contour moments can effectively describe the objects' shape.Different from global moments the contour moments scan all the pixels on the perimeter of object with a lower time and space complexity but the process of derivation is very complicated.We tried to simplify the procedure by describing the contour curve section with parameter equation.Based on the Green theorem binomial theorem was used only once while calculating the contour moments.Taking the ship projection images as examples general expressions of contour moments were calculated.The experiments showed that it operated faster than area moments and the centroid error was less than 2%.