A secure image watermarking using Chinese remainder theorem based on haar wavelet transform

摘要

This study proposed concealment of information through watermarking techniques using a combination of Haar Wavelet Transform (HWT) and Chinese Remainder Theorem (CRT) algorithms. The use of HWT can improve the imperceptibility of the watermarked image. While the CRT has a shorter operation and minimal distortion and provides security to copyright because of its insertion technique that indirectly also encrypts the copyright itself. Watermark insertion is done by using HWT on subband LL followed by CRT process. The evaluation standard that will be used in this research is Peak Signal to Noise Ratio (PSNR) and Normalized Correlation (NC). From the measurement results obtained the average value of PSNR 63.55dB, which shows the very high imperceptible quality of the watermarked image. While copyright extraction can be recovered perfectly with the value of NC 1.