Digital Watermarking Algorithm For Original Image

摘要

PURPOSE: A watermarking algorithm for minimizing distortion of an image is provided to prevent picture quality from varying and to make removal of a watermark difficult. CONSTITUTION: A watermarking algorithm generates a watermark sequence and aligns watermarks in the order of their size. Then, the algorithm discrete-cosine-transforms the entire size of the watermark sequence to obtain the average and energy of frequency factors other than DC(3), and compares the average and energy with proposed conditions(4). The algorithm inserts a watermark into a proposed position. The watermarking algorithm compares similarity of the watermarking technique with similarity of NEC band spreading technique while varying compression rate.