Abstract: Vectograph describes images and patterns.Its storage is much smaller than that of the bitmap of the same image.Big color block images are often used in the textile industry.Since the jacquard image is a big color block and the outline is clear,the chain-codemethod is adopted to trace the outline of every big color block and get the outlines of them.Then,the beeline and curve method is used for fitting the contours.Beeline fitting can keep the part of linearization and the acute angle of outlines of previous color blocks.For fitting the curve part,the least-squaremethod using three cubed Bezier curves is used.And good effect is achieved.