Print-Scan Resilient Binary Map Watermarking Based on DCT and Scrambling

This article describes how combing the characteristics of simple textures and uneven black area distribution of a binary map, a novel blind print-scan resilient watermarking scheme is proposed. First, the flipping probability of each pixel is calculated, and then the image characteristic value matrix is obtained by scrambling and partitioning. Second, a DCT transform is performed on the characteristic value matrix and then the DCT coefficients are modified according to the hidden data. After that, an inverse DCT is made to the modified DCT coefficient matrix, and the pixels of the corresponding block are flipped. Finally, the watermarked map is obtained by inverse scrambling. Experimental results and analysis show that the proposed scheme not only provides a large capacity and good imperceptibility, but also can resist the impact of a print-scan operation, and has strong robustness. Meanwhile, compared with the existing algorithms, it has a low implementation complexity and can be applied to military maps, engineering design drawings and other binary images.