基于Logistic混沌映射的比特级数字图像加密算法研究 Research on Bit-Level Digital Image Encryption Algorithm Based on Logistic Chaotic System

提出一种基于Logistic混沌映射的比特级数字图像加密方法。灰度图像的每个像素值采用八位的二进制数来表示，将二维灰度图转换为一维的0和1的数码串来处理。根据给定的初始值由Logistic映射及生成混沌序列，对混沌序列进行排序，得到位置索引，根据位置索引对原始图像进行比特级的置乱操作，可以达到集像素融合和像素置乱于一体的图像加密结果。实验表明，该算法简单易行，安全高效。 A bit-level digital image encryption method based on Logistic chaotic system is proposed. Each pixel value of a grayscale image uses eight-bit binary numbers, and the two-dimensional gray image is converted to a one-dimensional string containing 0 and 1. We generate the Logistic chaotic sequence with the given initial value, and then sort the chaotic sequence to obtain a location index. According to the location index, the original image is scrambled in bit-level. The pixels fusion and pixel scrambling encryption of an image are realized simultaneously. Experiments show that the algorithm is simple, safe and efficient.