Application of Digital Watermarking Technology in Anti-counterfeit Packaging

摘要

Hiding information in a color image is an effective method for the purpose of anti-counterfeiting, it can accurately identify authenticity in a certain range, and it is not easy to be copied and replicated. A new kind of watermarking algorithm for halftone images is proposed. Firstly the color image is treated as R, G, B single channel images, by using error diffusion algorithm the single channel image is converted into a halftone image, and then the watermark information is embedded in the halftone image by the proposed scheme of pixel swapping. Experimental results show that large amount of information can be embedded and extraction of the watermark information is clear, under conditions of rotating, clipping, etc, the watermark information still can be effectively extracted. This scheme can be used in packaging anti-counterfeiting printing.