The integration of Internet of Medical Things (IoMT) technology has revolutionized healthcare, allowing rapid access to medical images and enhancing remote diagnostics in telemedicine. However, this advancement raises serious cybersecurity concerns, particularly regarding unauthorized access and data integrity. This paper presents a novel, user-friendly, visible watermarking scheme for medical images—Visual and User-Friendly Medical Image Watermarking Scheme (VUF-MIWS)—designed to secure medical image ownership while maintaining usability for diagnostic purposes. VUF-MIWS employs a unique combination of inpainting and data hiding techniques to embed hospital logos as visible watermarks, which can be removed seamlessly once image authenticity is verified, restoring the image to its original state. Experimental results demonstrate the scheme’s robust performance, with the watermarking process preserving critical diagnostic information with high fidelity. The method achieved Peak Signal-to-Noise Ratios (PSNR) above 70 dB and Structural Similarity Index Measures (SSIM) of 0.99 for inpainted images, indicating minimal loss of image quality. Additionally, VUF-MIWS effectively restored the ROI region of medical images post-watermark removal, as verified through test cases with restored watermarked regions matching the original images. These findings affirm VUF-MIWS’s suitability for secure telemedicine applications.

We propose a separable, reversible watermarking scheme in encrypted images for privacy preservation. The Paillier cryptosystem is used for separable detection and decryption. Users may want to use cloud services without exposing their content. To preserve privacy, the image owner encrypts the original image using a public key cryptosystem before sending it to the cloud. Cloud service providers can embed the watermark into encrypted images by using a data-hiding key without knowing and destroying the original image. Even though the cloud service providers do not know the original image content, they can use the data-hiding key to detect the watermark from the encrypted image for authentication. Besides, the image owner can use the private key to directly decrypt the watermarked encrypted image to get the original image without any distortion due to its homomorphic property. Experimental results show the feasibility of the proposed method, which can provide efficient privacy-preserving authentication without degrading security.

Data hiding encompasses a wide range of applications related to hiding messages in digital images. The visual redundancy of images makes it possible to embed data in the images without attracting attention. Increasing the hiding capacity and decreasing the hiding distortion are prime objectives that data hiding intends to achieve. In this paper, we propose a high-payload data hiding scheme based on absolute moment block truncation coding (AMBTC) to minimize the impact of hiding. A two-level minimum mean square error (MMSE) quantizer generated by AMBTC is used to decrease the distortion associated with hiding. Also, we present a lookup table based on the symmetric property for adaptively hiding secrets in pixels to achieve high hiding capacity. We can embed almost 1.9 bits per pixel (bpp) with a high image quality of an average of 31 dB. Only 5.3% of pixels are changed during the data-hiding process. Compared with other schemes, we can use 1 bpp more relative payload for embedding with the same stego image quality. The experimental results show that the proposed scheme has better hiding performance because it allows a huge amount of secret data to be hidden while maintaining the high visual quality of the stego image.

The rise of the Internet has transformed communication and information access, but it also raises serious privacy concerns, especially regarding personal image sharing. This paper presents a novel reversible and authenticable data-hiding scheme for encrypted images that utilizes interpolation techniques and substitution methods. Our encryption system achieves a lower correlation among neighboring pixels, ensuring a more uniform distribution in the encrypted image. The stego images do not reveal any information about the original cover image or secret data. The embedded authentication data provides the ability to verify the authenticity of the image and localize the tampering. Experimental results show that our scheme can securely protect an image from unauthorized access and verify its authenticity.