An embedding and extracting method of a reversible watermark

• Main Authors: YE WUJIAN, ZHANG TIANCONG, WENG SHAOWEI, LIU YIJUN, ZHANG ZIWEN
• Format: Patent
• Language: Chinese; English
• Published: 10.05.2019
• Subjects: CALCULATING; COMPUTING; COUNTING; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; PHYSICS

The invention provides a reversible watermark embedding method, which comprises the following steps of: processing pixels to prevent pixels from overflowing and distorting, dividing a carrier image into image blocks which are not overlapped with one another, and sorting to obtain a one-dimensional pixel sequence; Predicting two by two according to a pixel sequence order by using the three maximumpixels and the three minimum pixels to obtain a difference value; Classifying all image blocks of which the local complexity is less than or equal to a first preset threshold into a first to-be-transformed set; judging whether the image block needs watermark embedding or not according to the difference value; and if yes, watermark embedding is carried out on the image block, and watermark embedding is further completed. The second large pixel is predicted by using the third large pixel, and the maximum pixel is predicted by using the second large pixel at the same time, so that the two maximumpixels and the two minimu