Research on Image Watermarking Algorithm Based on DCT

The technology of image watermark is very important in the field of signal processing. The knowledge of image watermark, as well as the DCT/IDCT had been introduced in this paper. A new digital watermarking encryption algorithm had been introduced which the watermarking information was based on the size of the image. The watermark's embedding and extraction had been performed on two images for verifying this watermarking algorithm by MATLAB, and the result show that the adaptive algorithm is effective.