Department of Electronic Engineering, National I-Lan University, Yilan 26047, Taiwan.
Department of Information Management, St. Mary's Junior College of Medicine, Nursing and Management, Yilan 26647, Taiwan.
Sensors (Basel). 2022 Dec 29;23(1):370. doi: 10.3390/s23010370.
This paper presents a novel approach for directly hiding the pixel values of a small color watermark in a carrier color image. Watermark embedding is achieved by modulating the gap of paired coefficient magnitudes in the discrete cosine transform domain according to the intended pixel value, and watermark extraction is the process of regaining and regulating the gap distance back to the intensity value. In a comparison study of robustness against commonly encountered attacks, the proposed scheme outperformed seven watermarking schemes in terms of zero-normalized cross-correlation (ZNCC). To render a better visual rendition of the recovered color watermark, a generative adversarial network (GAN) was introduced to perform image denoising and super-resolution reconstruction. Except for JPEG compression attacks, the proposed scheme generally resulted in ZNCCs higher than 0.65. The employed GAN contributed to a noticeable improvement in perceptual quality, which is also manifested as high-level ZNCCs of no less than 0.78.
本文提出了一种新的方法，可以直接将小颜色水印的像素值隐藏在载体彩色图像中。水印嵌入是通过根据预期像素值来调制离散余弦变换域中配对系数幅度的间隙来实现的，而水印提取是恢复和调节间隙距离回到强度值的过程。在对常见攻击的鲁棒性进行的比较研究中，所提出的方案在归一化零相关系数（ZNCC）方面优于七种水印方案。为了更好地显示恢复的彩色水印，引入了生成对抗网络（GAN）来进行图像去噪和超分辨率重建。除 JPEG 压缩攻击外，所提出的方案通常会导致 ZNCC 高于 0.65。所采用的 GAN 有助于显著提高感知质量，这也表现为不低于 0.78 的高水平 ZNCC。
