A JPEG Compressed Image Encryption Method Based on Shamir Secret Sharing Scheme

With the rise of cloud computing and social networks, images, as a significant representative of the multimedia big data era, hold undeniable value. Among them, JPEG images play a critical role in global image transmission and storage. To address security vulnerabilities and internet threats, both the academic world and the industrial world have proposed various security protection schemes for JPEG images. However, traditional JPEG encryption compression methods are overly reliant on keys, and once a key is lost, the integrity of the original image cannot be restored. To solve this issue, Secret Image Sharing (SIS) technology has demonstrated tremendous potential in modern data sharing, offering high security and fault tolerance, which effectively avoids excessive concentration of key dependency. In this paper, we propose a novel secret JPEG image sharing scheme that introduces Galois field-based SIS technology into the Huffman coding step of the JPEG compression process. This not only enhances the visual security of the compressed image but also resolves the problem of poor key loss tolerance. Furthermore, we improved the original scheme, making the encrypted ciphertext image harder to recognize while ensuring both the compression sharing and the restoration of the original image. Experimental results show that our scheme fully complies with the format requirements and exhibits high security.