说明：  Recognition of visual patterns and characters are independent of position, size, and orientation in the visual field has been the goal of much recent research. The method presented in this paper meets all these condition. An off-line signature matching system which is based on Hu moment invariant method is presented here. Signature matching uses a four - steps process. In first step the scanned or captured color images are initially converted to grey scale. Second step performs normalization and digitization of the original signature. Noise reduction (also called “smoothing” or “noise filtering”) is one of the most important processes in image processing is performed in third step and then moment invariant vectors are obtained in the last step. Signature matching system is implemented using MATLAB and ability of the system can be increased by using additional features in the input data set.