Anti-counterfeiting Technology Research Based On Barcode And Digital Watermark

The rapid development of IOT technology has provided a broad platform for application of two-dimenisonal barcode in china. However, coding method of two-diminsional barcode is open, and uniform standard coding model makes it insufficient in terms of confidentiality, affecting its scope of application seriously. Digital watermarking technology is put forward to solve the identification problem. Therefore, the combination of the two kinds of technologies will significantly enhance the confidentiality of two-dimensional barcode, thereby enlarging the range of use. In addition, combined with the strong error correction ablity of barcode, setting barcode as watermark, will improve the robustness of traditional watermark method. In view of the above reasons, this thesis proposes a common anti-counterfeit method based on barcode and digital watermark.This thesis uses barcode watermark concept based on the analysising of RS error correction algorithm. Digital watermark firstly encoded in terms of QR barcode and then embeded into frequency domain coefficients of the host image after pretreatment steps towards barcode, Such as removing format information, deleting barcode boundary. In this thesis, the method to embed format information and coding information of QR barcode is different. Through the adjustment of host image block DCT coeffiecient variance, the format information is embedded. While QR barcode coding information is embedded by changing the relationship between the mean of host image frequency coefficients and designated coefficient. Watermark embedding method has strong robustness itself. In addition, Comparing with the watermark system without coding processing, this method improves the security and robustness of watermark system, enhancing the anti-attack performance.In the watermark barcode rearch, the wide used QR barcode in our country is choosed as the object of study. This thesis discusses the spatial structure of the QR barcode and put forward six kinds of embedded conditions, in order to satisfy imperceptibility requirement. Then structure adjustment method is used, the watermark information is embedded into the suitable edge of barcode in the barcode fault-tolerant condition. According to the forms of the watermark, this thesis uses different preprocessing operations towards text watermark and image watermark to meet different application requirements.In short, the combition of two-dimensional barcode and digital watermark can realize complementary advantages, enchancing their range of application. So it has important research value.