No abstract

The volume of securely encrypted data transmission increases continuously in modern society with all things connected. Towards this end, true random numbers generated from physical sources are highly required for guaranteeing security of encryption and decryption schemes for exchanging sensitive information. However, majority of true random number generators (TRNGs) are mechanically rigid, and thus cannot be compatibly integrated with some specific flexible platforms. Herein, we present a flexible and stretchable bionic TRNG inspired by the uniqueness and randomness of biological architectures. The flexible TRNG film is molded from the surface microstructures of natural plants (e.g., ginkgo leaf) via a simple, low-cost, and environmentally friendly manufacturing process. In our proof-of-principle experiment, the TRNG exhibits a fast generation speed of up to 1.04 Gbit/s, in which random numbers are fully extracted from laser speckle patterns with a high extraction rate of 72%. Significantly, the resulting random bit streams successfully pass all randomness test suites including NIST, TestU01, and DIEHARDER. Even after 10,000 times cyclic stretching or bending tests, or during temperature shock (−25–80 °C), the bionic TRNG still reveals robust mechanical reliability and thermal stability. Such a flexible TRNG shows a promising potential in information security of emerging flexible networked electronics. Electronic Supplementary Material Supplementary material (light path diagram of transmitted laser speckle, pseudo random pattern, statistical distribution of bionic microstructures, haze of the bionic TRNG film, multi-layer circular laser intensity pattern, percentage of bit 0/1 for different hashed images, Pearson correlation coefficient between 100 different speckle images, the whole process of randomness extraction, SEM images of the flexible TRNG film after 10,000 times stretching and bending, continuous work stability of the TRNG at low or high temperature, light path diagram of reflective laser speckle, and detailed randomness test results of NIST, TestU01, and DIEHARDER) is available in the online version of this article at 10.1007/s12274-022-4109-9.

Recently more and more researches in the information security field have been focused on the digital image zero-watermarking technology which is an important mean for protecting the digital multimedia copyright. In this paper, first the research background of image zero-watermarking is analyzed; and then the typical algorithms are presented and discussed; finally the performance of these typical algorithms are analyzed and experimented.

As the first step in 3D point cloud process, registration plays an critical role in determining the quality of subsequent results. In this paper, an initial registration algorithm of point clouds based on random sampling is proposed. In the proposed algorithm, the base points set is first extracted randomly in the target point cloud, next an optimal corresponding points set is got from the source point cloud, then a transform matrix is estimated based on the two sets with least square methods, finally the matrix is applied on the source point cloud. Experimental results show that this algorithm has ideal precision as well as good robustness.

False alarm and missing alarm are two of the most important performances for multiple bits watermarking systems. In this paper, we study false alarm and missing alarm probability models when multiple watermarks or multiple bits watermarks embedded. We derive the false alarm and missing alarm probability models for dither modulation from the detection principle of the detectors. The theoretical results are compared with the experimental results obtained in the case of random work and watermark, and the comparison validates the accuracy of the models, and it also shows that random work and watermark have little influence on the false alarm and missing alarm probabilities, and this is the same with the situation when only one bit watermark is embedded by DM.