Aiming at solving the problems that the existing anti-screening watermarking algorithms cannot take into account the robustness, invisibility and watermark capacity, this paper proposed a robust blind watermarking algorithm based on randomly distributed circular templates. Firstly, it converted the hexadecimal watermark sequence into a fixed angle value, and then generated a series of circular templates with angle information according to the random line distribution algorithm. Secondly, it separated the original host image according to the three primary color channels and took out the blue component. Thirdly, it performed integer wavelet transform on blue component and took out low frequency sub-band(LL). Fourthly, it divided the LL into blocks and selected several watermark embedding blocks with a selected key. Finally, it embedded the circular templates in the selected blocks. In addition, in order to increase the watermark capacity, it chose the hexadecimal watermark password to replace the QR code or barcode. In order to improve the invisibility of the watermark, it embedded the watermark templates in the low frequency sub-band of the integer wavelet transform. In order to balance the transparency and robustness of the watermark, it used the particle swarm optimization algorithm(PSO) to obtain the optimal embedding strength adaptively. In order to solve the image distortion caused by shooting, it performed geometric correction on the captured image before watermark extraction. This paper selected images on the data set USC-SIPI to implement experiments related to common attacks and screen capture attacks, and compared the proposed algorithm with other six algorithms with this image data set. The experimental results show that the algorithm can not only ensure the invisibility of watermark, but also resist various types of common attacks. And within a certain range of shooting distance and shooting angle, the algorithm can effectively extract the watermark password, it also improves the watermark capacity and has good robustness against screen shots.

[2022-09-21] Accepted Paper /doc/2022.06.0314/v1

[2023-02-05] Printed Article /doc/2022.06.0314/v2