The task of preserving patient data is becoming more sophisticated with the evolution of technology and its integration with the medical sector in the form of telemedicine and electronic health (e-health). Secured medical image transmission requires adequate techniques for protecting patient privacy. This study aims at encrypting Coronavirus (COVID-19) images of Computed Tomography (CT) chest scan into cipherimages for secure real-world data transmission of infected patients. Provably safe pseudo-random generators are used for the production of a "key-stream" to achieve high privacy of patient data. The Blum Blum Shub (BBS) generator is a powerful generator of pseudo-random bit-strings. In this article, a hashing version of BBS, namely Hash-BBS (HBBS) generator, is presented to exploit the benefits of a hash function to reinforce the integrity of extracted binary sequences for creating multiple key-streams. The NIST-test-suite has been used to analyze and verify the statistical properties of resulted key bit-strings of all tested operations. The obtained bit-strings showed good randomness properties; consequently, uniform distributed binary sequence was achieved over the key length. Based on the obtained key-streams, an encryption scheme of four COVID-19 CT-images is proposed and designed to attain a high grade of confidentiality and integrity in transmission of medical data. In addition, a comprehensive performance analysis was done using different evaluation metrics. The evaluation results of this study demonstrated that the proposed key-stream generator outperforms the other security methods of previous studies. Therefore, it can be successfully applied to satisfy security requirements of transmitting CT-images for COVID-19 patients.

随着技术的发展及其以远程医疗和电子健康（e-health）的形式与医疗部门的整合，保存患者数据的任务变得越来越复杂。安全的医学图像传输需要足够的技术来保护患者隐私。本研究旨在将计算机断层扫描 (CT) 胸部扫描的冠状病毒 (COVID-19) 图像加密为密码图像，以确保感染患者的真实数据传输安全。可证明安全的伪随机生成器用于生成“密钥流”，以实现患者数据的高度隐私。Blum Blum Shub (BBS) 生成器是一个强大的伪随机位串生成器。在本文中，BBS 的哈希版本，即 Hash-BBS (HBBS) 生成器，提出利用散列函数的好处来增强提取的二进制序列的完整性以创建多个密钥流。NIST 测试套件已用于分析和验证所有测试操作的结果关键位串的统计属性。得到的比特串表现出良好的随机性；因此，在密钥长度上实现了均匀分布的二进制序列。基于获得的密钥流，提出并设计了一种四张 COVID-19 CT 图像的加密方案，以实现医疗数据传输的高度机密性和完整性。此外，使用不同的评估指标进行了全面的性能分析。本研究的评估结果表明，所提出的密钥流生成器优于先前研究的其他安全方法。因此，它可以成功地应用于满足 COVID-19 患者传输 CT 图像的安全要求。