A Novel Image Zero-Watermarking Scheme Based on Non-Uniform Triangular Partition

In this paper, a novel time-domain zero-watermarking algorithm based on Non-Uniform Triangular Partition (NTP) is proposed. NTP is an image representation method in which the bivariate polynomials are calculated and used to represent the pixel values in each triangular region under a set control error. The number of triangles in each $8\times 8$ region is counted and recorded as a feature matrix which will be mapped to a binary watermark scrambling by the Arnold scrambling method to enhance the security of the algorithm. The feature matrix and the scrambled binary watermark are stored as zero watermarks. Experimental results show that the proposed algorithm is robust to various attacks, such as JPEG compression, rotation, Gaussian noise and salt and pepper noise.