Hybrid Compression and Lightweight Encryption of Color Image
Bo-fan Gong · 2020
Based on generalized Arnold transformation and RC4 stream cipher, this paper proposes a method to encrypt images in the transform-domain. The RGB color image is transformed into YUV form first, then the Arnold transformation is carried out according to 8x8 size blocks as the basic unit to scramble the pixel position, and then each block is DCT transformed and quantified. Finally, the quantization results are encoded by run-length and differential coding to achieve data compression, and the final result is obtained by encrypting the coded data with RC4 stream cipher. The encryption method has the characteristics of large key space, mixing the YUV three color gamuts, and combining with the transform domain of the image. Accordingly, the security is high. In addition, the results of the experiments show that the algorithm runs fast and the pixel value distribution of cipher text image is more uniform, that is, the encryption effect is good.