Enhancing security and privacy of images on cloud by histogram shifting and secret sharing

In contemporary society, people can easily use any smart device at hand to capture images of scenery and upload them to cloud storage. Cloud storage is widely used for storing user generated multimedia content. However, the risk of potential private data leakage exists because cloud storage is normally in a public domain. To protect the privacy information of images on cloud storage, we propose an integrated scheme involving invisible watermarking, masking and secret sharing methods. The histogram modification-based scheme can achieve reversible data hiding to ensure the integrity and confidentiality of image data. Additionally, a secret sharing scheme was used to further improve the security of data access. The evaluation results show that the proposed system may prevent malicious users from accessing private images.