Image Watermarking Using Wavelet Coefficient

웨이브렛 계수를 이용한 영상 워터마킹

In this paper, we proposed an watermarking algorithm in which invariable sign of DWT coefficients should be used and by which the quality of digital image can be preserved for the protection of copyright. According to the algorithm, through the calculation of the sign DWT coefficients and the use of elements, position of watermark and size value should be decided. By so doing, the algorithm can improve image quality(PSNR) and obtain good efficiency with which strong watermark can be inserted into the digital image.