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Improving Security and Privacy of Images on Cloud Storage by Histogram Shifting and Secret Sharing

Nowadays people can easily use any smart device at hand to capture scenery and then upload it to the cloud storage. Cloud storages are widely used for storing the generated multimedia content. However, the risk of potential private data leakage may exist since cloud storages are normally in a public domain. To enhance the security and privacy of images on the cloud storage, we proposed an integrated scheme evolving invisible digital watermarking and masking which are based on the histogram shifting method. The histogram modification based scheme can achieve reversible data hiding, to ensure the integrity and the confidentiality of the image data. Additionally, we use the secret sharing scheme to keep the secret keys to further improve the security of data access. The evaluation results show that the proposed system can effectively prevent the malicious user from accessing the private images.