In this paper, we propose a novel method for reversible data hiding (RDH) for OpenEXR images in the compressible encrypted domain. There exist three main advantages in the proposed method. First, it introduces an encryption-then-compression system, which provides block-by-block encryption, to the encryption process. This leads to a high compression efficiency for marked encrypted images. In the en- crypted domain, we embed a payload using an RDH method based on prediction error expansion. This makes the hiding capacity of our method high. The method further allows for flexible restoration patterns; we can decrypt a marked encrypted image without data extraction. In this case, a marked image will be obtained. In addition, both the encryption and data hiding processes are carried out while preserving the dynamic range of an original image. This also contributes both to compression efficiency and marked-image quality. In an experiment, we evaluate the hiding capacity, marked-image quality, and compression efficiency by using JPEG XT so as to clarify the effectiveness of our proposed method. Additionally, the security of the method is also discussed.

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