Improved differential energy watermarking (IDEW) algorithm for DCT encoded image and video

This paper addresses the real-time requirement of video watermarking and proposes a new improved DEW-based algorithm, which employs two measures to improve the DEW algorithm's performance. One is using the ratio of energy difference to total energy R/sub D/ to replace energy difference D as pattern to embed label bits. The other is that the selection of embedding cut-off index c doesn't need that both lc-subregions A and B have enough energy. The experimental results show that the improved algorithm performs better on watermark's visual quality impact, capacity and robustness than the original DEW algorithm.