## 1 Introduction  
With the rapid development of the Internet of Things, advanced high-end computing equipment, and the popularization of communication technology, there are already many applications developed on the IoT-connected platforms, such as cloud-based vehicle routing [1], medical and healthcare [2], freight transportation system [3], blockchain-based IoT [4], etc. The automobile was hailed as the fourth C after the 3C industry. In recent years, after various technology companies have accelerated their investment in Internet of Vehicles (IoV), this industry has set off the biggest change in a century. With the increasing popularity of connected medical devices, companies from the communications technology (ICT) and financial services industries are taking the lead. Healthcare and life sciences are inspiring industries that are close behind. The emerging Internet of Medical Things (IoMT) is becoming a form of medical care. This major change not only helps to simplify the clinical workflow, which is helpful for an infected patient to identify symptoms [5] and provides better treatment rapidly, but also helps to realize remote care. Blockchain technology, a solution to ensure a trust relationship, has widespread applications relating to Internet of Things (IoT) and Industrial IoT (IIoT) [6]. Blockchain and IIoT has been gaining enormous attention in areas beyond its cryptocurrency roots since more or less 2014: blockchain and cybersecurity, blockchain and finance, blockchain and anti-counterfeit labels, blockchain and smart contracts [7], etc. People transmit a large amount of media content on the Internet to achieve real-time interactions. At the same time, data are exposed on these public platforms and have run into unforeseen risks. It is easy to attract the attention of stakeholders and even to be maliciously attacked, causing the attacked files tampered with or even destroyed before they are spread. Therefore, how to avoid malicious tampering and misappropriation of secret information is an urgent task. With the rapid growth of the number of the IoT applications, the amount of data that needs to be transmitted also grows rapidly in multiple activities and even about the environmental conditions that we need to monitor and control at a distance. For users, the environment of various IOT applications contains a lot of key and sensitive information. Therefore, higher requirements are put forward to protect the secure transmission of multimedia data to the destination, and information hiding was born in response to this demand. Information hiding technology, also known as steganography, is to use the content in digital media as a cover media to embed the secret message that you want to convey into the content. To protect the secret message and increase security, it is now used in various applications, for example, identity verification used to protect information content and intellectual property rights [8; 9; 10]. These technologies hide the secret information in the multimedia content. During transmitting, it is not easy to find that there is a secret message in the content. The receiving party only needs to know how to extract the information hidden in the content so that complete information can be obtained safely. In response to different application methods, two categories are distinguished: digital watermarking and information hiding. Digital watermarking is mainly used to protect intellectual property rights and verify the integrity of information; information hiding is to hide the secret message in the embedded content, not easily discovered, and the restored content also has a considerable degree of image quality. In the past few decades, reversible data hiding (RDH), also known as lossless data hiding, has gradually become a very active research topic in the field of data hiding. In reversible data hiding, after the confidential information is retrieved, the original images, such as medical images or military images, are not allowed to degrade at all, but its application is now extended.