The Research On Digital Watermark Technology Based On2D Barcode

The two-dimensional barcode encoding mechanism have a fixed standard and theinformation stored in two-dimensional barcode can be tampering, so the security of information intransfer could be strengthened. Digital watermarking technology is born to solve these securityissues, and the combination of two techniques is important to ensure that the two-dimensionalcode is widely used. In this paper, the compressed digital image storage algorithm which based onPDF417two-dimensional barcode and the digital watermark embedding algorithm which based onPDF417two-dimensional barcode structural changes were improved. Given the experimentalverification of two algorithms.This paper describes a storage method of digital image compression based on PDF417two-dimensional barcode and an embedding method of digital watermark based on PDF417two-dimensional barcode image space structure change. Two work aspects description in detail asfollow:1. Improved digital image compression algorithm, and is applied to the two-dimensionalbarcode digital image storage. First, process the digital image though preprocessing operation andextract contour of the target area. Second, convert the contour to Freeman chain code sequence.Finally, analysis the change of the Freeman chain code sequence and achieve the feature pointextraction though B-spline curves error control. In order to achieve a two-dimensional barcodedigital image compression and storage, transforming the feature points information and the colorinformation to PDF417two-dimensional barcode symbol image. Experimental results show thatwe can extract the minimum feature points which could accurately represent the target regioncontour. The improved algorithm accomplished the digital image compression and completed thelarge amount of data storage.2. Improved digital watermark embedding algorithm. First, in the choice of imagewatermarking, we choose the HASH value as watermark information which is directly related toimage content. And then combined with PDF417two-dimensional barcode own Fault-tolerant ofspatial structure to change some pixel values which are distributed in black and white portions junction. Experimental results show that this method can be embedded in a large number ofwatermark information in the limited two-dimensional barcode image, and does not affect thetwo-dimensional barcode reading. Since the HASH value is highly sensitive, even a small amountof information has been tampered with, the original information can be performed by the HASHvalue.As a reference of this algorithm, the concrete implementation process and effect of theimplementation of each module are also given in this paper, and the algorithm analysis section ofthe key operations have detailed instructions. Finally analyzes the occasions that this method canbe applied in areas. What to be improved and the follow-up research direction are discussed in thispaper.