In our present society, 3D objects play an increasingly important role in many different domains, especially with the development of meta environments. Many applications demand large 3D objects, which makes their compression a requirement. Meanwhile, 3D objects are also exposed to various security problems during online storage and transmission. Consequently, security aspects such as copyright and authentication are essential for 3D objects. In this paper, we propose a simultaneous 3D object watermarking and compression method based on Draco. A watermarking step is integrated within Draco, Google’s 3D compression method, which is rapidly being universally adopted as standard. The proposed method enables a large bit embedding rate, which can be used for copyright information. The proposed method is also, to the best of our knowledge, the first watermarking method for 3D objects compressed with Draco.

Nowadays, 3D objects are frequently stored and shared online, where they become vulnerable to attacks. Therefore, applying security measures such as encryption is crucial. Once the 3D object is encrypted and stored online, a third party who is not authorized to access the content of the 3D object may need to embed hidden data in the 3D object. In this paper, we propose a new MSB-based reversible data-hiding in the encrypted domain method for 3D objects, which uses a Hamiltonian path to establish a unique order for the vertices of a 3D object. For the reconstruction step, we select the smallest distance between vertices to accurately predict the MSB value of the mantissa for each coordinate. Our proposed method is format compliant, avoids any size expansion, and does not require auxiliary file, while guaranteeing the reversibility of the marked encrypted 3D object, even when tested on a large database of 3D objects.

With the increasing popularity of 3D objects in industry and everyday life, 3D object security has become essential. While there exists methods for 3D selective encryption, where a clear 3D object is encrypted so that the result has the desired level of visual security, to our knowledge, no method exists for decrypting encrypted 3D objects hierarchically. In this paper, we are the first to propose propose a method which allows us to hierarchically decrypt an encrypted 3D object according to a generated ring of keys. This ring consists of a set of keys that allow a stronger or weaker decryption of the encrypted 3D object. Each hierarchically decrypted 3D object has a different visual security level, where the 3D object is more or less visually accessible. Based on a master key, these hierarchical keys are generated using our method during the encryption process. Our method is essential when it comes to preventing trade secrets from being leaked from within a company or by exterior attackers. It is also ecologically friendly and more secure than traditional selective encryption methods.

For over a decade, 3D objects are an increasingly popular form of media. It has become necessary and urgent to secure them during their transmission or archiving. In this article, we propose a new method to obtain a watermarked 3D object from high-capacity data hiding in the encrypted domain. Based on the homomorphic properties of the Paillier cryptosystem, our proposed method allows us to embed several secret messages in the encrypted domain with a high-capacity. These messages can be extracted in the plain-text domain after the 3D object decryption. To the best of our knowledge, we are the first to propose a data hiding method in the encrypted domain where the high-capacity watermark is conserved in the plain-text domain after the 3D object is decrypted. The encryption and the data hiding in the encrypted domain are format compliant and without size expansion, despite the use of the Paillier cryptosystem. Each time a new message is embedded in the encrypted domain, flags are added in order to indicate which blocks are still available for the embedding of additional messages. After the decryption of a watermarked encrypted 3D object, our method produces a watermarked 3D object which is visually very similar to the original 3D object. From the decrypted watermarked 3D object, we can then extract all the embedded messages directly in the plain-text domain, without the need for an auxiliary file. Moreover, large keys are used, rending our method secure for real-life applications.

3D objects play an essential role in industry and everyday life. They are often stored on the cloud and transferred many times during their existence, and so 3D object security is essential. To the best of our knowledge, no method exists to hierarchically decrypt fully encrypted 3D objects. In this paper, we propose a new method to hierarchically decrypt a 3D object so that the visual accessibility of the resulting 3D object depends on the user's rights. For that, it is based on the hierarchy of the key used during the decryption. The decryption key is selected from a ring of hierarchical keys which are generated and distributed to the respective users during the encryption process. The proposed method is eco-friendly as a single 3D object is fully encrypted (confidential level) and available to several users with different rights. Experimental results show that our method is efficient and can be used for real applications.

Today, 3D objects are an increasingly popular form of media. It has become necessary to secure them during their transmission or archiving. In this paper, we propose a two tier reversible data hiding method for 3D objects in the encrypted domain. Based on the homomorphic properties of the Paillier cryptosystem, our proposed method embeds a first tier message in the encrypted domain which can be extracted in either the encrypted domain or the clear domain. Indeed, our method produces a marked 3D object which is visually very similar to the original object. It seeks to be format compliant and to preserve the original size of the data, without the need for an auxiliary file. Moreover, large keys are used, rending our method secure for real life applications.