QR code watermarking algorithm based on wavelet transform

Copyright protection and authentication have become increasingly more important in daily life. The digital watermark is one of the techniques invented to tackle this issue. In this paper, a digitally invisible watermark is embedded in a QR code image by means of wavelet transform. In the embedding process, a binary image, logo, is transformed into a corresponding watermark and then embeded into a selected subband. The experimental results illustrated that, for all the cases considered in this paper is more robustness to attacks and as such it can serve as a viable copyright protection and authentication tool.