Reversible Watermark Algorithm Based on the Diamond Pixel Pairs Complementary Embedding

Abstract

Abstract To enhance the invisibility of existing reversible watermarking algorithms and improve the embedding capacity, a reversible watermarking algorithm based on diamond pixel pairs complementary embedding is proposed. To prevent pixel value overflow, the carrier image is preprocessed and divided into blocks first. Then the pixel blocks are divided into two half-planes, gray and white. Finally, the watermark is embedded in the horizontal and vertical directions: the target pixel in the smooth pixel block and the 4 reference pixels in the cross neighborhood are subtracted, and the histogram is constructed according to the difference value. The first embedding is performed in the gray half-plane using the histogram shift method, and then the second embedding is performed in the white half-plane. The same method is used in the vertical direction to embed to balance the distortion caused by the horizontal embedding process. The experimental results show that under the same embedding capacity, the mean PSNR (Peak to signal noise ratio) of this algorithm is 6.92 dB higher than that of the non-complementary embedding scheme; compared with other related algorithms, under the same PSNR value, this algorithm has better embedding performance.