An Algorithm for Digital Watermark Based on Pseudo-Random Sequence and DCT for Remote Sensing Image

According to the basic requirements of digital watermark for remote sensing image,an algorithm for digital watermark based on pseudo-random sequence and DCT for remote sensing image was proposed.Firstly,the original image was segmented,and the image blocks were selected by the pseudo-random sequence.Then,the low frequency coefficients after DCT were got,and the watermark information was embedded in the low frequency coefficients of each image block using the quantitative method.Finally,the errors of embedded image were controlled by the accuracy constraints.Because the watermark information embedded was done with quantitative method,the watermarked image authentication needed no information about the original image.This algorithm realized blind extraction of digital watermarking.The experimental results show that the proposed algorithm the robustness and achieve near-zero change of remote sensing image.