A DCT domain based digital image watermarking of JPEG files.

摘要

This thesis studies digital image watermarking of JPEG files in the DCT (Discrete Cosine Transform) domain. The algorithm which involves watermark embedment and extraction was developed using MATLAB. Finally, the robustness of the watermark was judged with respect to JPEG compression and additive Gaussian noise using the parameters PSNR (Peak Signal-to-Noise Ratio) and normalized crosscorrelation.