Digital watermarking has shown its effectiveness in protecting multimedia content. However, existing watermarking is predominantly tailored for specific media types, rendering them less effective for the protection of content displayed on computer screens, which is often multi-modal and dynamic. Visual Screen Content (VSC), is particularly susceptible to theft and leakage through screenshots, a vulnerability that current watermarking methods fail to adequately address. To address these challenges, we propose ScreenMark, a robust and practical watermarking method designed specifically for arbitrary VSC protection. ScreenMark utilizes a three-stage progressive watermarking framework. Initially, inspired by diffusion principles, we initialize the mutual transformation between regular watermark information and irregular watermark patterns. Subsequently, these patterns are integrated with screen content using a pre-multiplication alpha blending technique, supported by a pre-trained screen decoder for accurate watermark retrieval. The progressively complex distorter enhances the robustness of the watermark in real-world screenshot scenarios. Finally, the model undergoes fine-tuning guided by a joint-level distorter to ensure optimal performance. To validate the effectiveness of ScreenMark, we compiled a dataset comprising 100,000 screenshots from various devices and resolutions. Extensive experiments on different datasets confirm the superior robustness, imperceptibility, and practical applicability of the method.

Audio watermarking has been widely applied in copyright protection and source tracing. However, due to the inherent characteristics of audio signals, watermark localization and resistance to desynchronization attacks remain significant challenges. In this paper, we propose a learning-based scheme named SyncGuard to address these challenges. Specifically, we design a frame-wise broadcast embedding strategy to embed the watermark in arbitrary-length audio, enhancing time-independence and eliminating the need for localization during watermark extraction. To further enhance robustness, we introduce a meticulously designed distortion layer. Additionally, we employ dilated residual blocks in conjunction with dilated gated blocks to effectively capture multi-resolution time-frequency features. Extensive experimental results show that SyncGuard efficiently handles variable-length audio segments, outperforms state-of-the-art methods in robustness against various attacks, and delivers superior auditory quality.

Digital steganography embeds secret messages into images via invisible modifications, posing challenges for steganalysis, which seeks to detect these alterations by analyzing subtle shifts in image distributions. Previous steganalysis efforts primarily focus on enhancing the steganographic signal while suppressing image semantic content, such as through high-pass filtering. However, these empirically designed methods often lack theoretical underpinnings, exhibiting reduced detection accuracy, particularly at low embedding capacities. To address these limitations, we propose an innovative steganalysis approach that transforms images into pure Gaussian noise representations, actively amplifying the subtle distribution shifts introduced by the steganographic processes in spatial images. This paper pioneers the application of diffusion models to magnify steganographic signals, proposing a new paradigm for further research. Specifically, we iteratively perform forward steps of the probability flow in diffusion models to diminish semantic information. By utilizing the natural spreading properties of the diffusion process, we have theoretically validated the efficacy of each forward step in amplifying differences in noise patterns between cover and stego samples. These magnified differences can be easily captured by a simple classifier—a two-layer MLP. Extensive experiments demonstrate the effectiveness of our method, highlighting detection accuracy gains of 10% to 20% under standard conditions and an average 6.7% increase at low embedding rates compared to existing schemes.

Pancreatic NEuroendocrine Tumors (pNETs) are very rare endocrine neoplasms that account for less than 5% of all pancreatic malignancies, with an incidence of only 1–1.5 cases per 100,000. Early detection of pNETs is critical for improving patient survival, but the rarity of pNETs makes segmenting them from CT a very challenging problem. So far, there has not been a dataset specifically for pNETs available to researchers. To address this issue, we propose a pNETs dataset, a well-annotated Contrast-Enhanced Computed Tomography (CECT) dataset focused exclusively on Pancreatic Neuroendocrine Tumors, containing data from 469 patients. This is the first dataset solely dedicated to pNETs, distinguishing it from previous collections. Additionally, we provide the baseline detection networks with a new slice-wise weight loss function designed for the UNet-based model, improving the overall pNET segmentation performance. We hope that our dataset can enhance the understanding and diagnosis of pNET Tumors within the medical community, facilitate the development of more accurate diagnostic tools, and ultimately improve patient outcomes and advance the field of oncology.

Screenshot, which is a common tool in office work, has become a significant threat to organizations like companies and research institutions. Malicious users can easily leak sensitive information like business secrets and research data by taking a screenshot and spreading onto the Internet. While existing watermarking schemes serve as useful tools for leakage tracing, they fall short in the scenario of arbitrary screenshot. Most current methods are file-targeted, focusing on embedding watermark for a single file of one type at a time, making it hard to handle arbitrary content on screen. To address the issues above and better satisfy the need of the scenario, we propose ScreenGuard, a novel watermarking scheme targeted for the screen itself to protect arbitrary screen content shown on it. Unlike previous watermarking schemes, ScreenGuard does not modify the content itself. Instead, we generate a transparent mask template based on the watermark, tile it to the size of the screen to form a complete transparent mask, and overlay this mask onto the screen. This ensures that any screenshots taken will contain our watermark. We then train a locator and a decoder to extract watermarks from suspected leaked screenshots to trace leaks to their source. We summarized five properties that needs to be satisfied in the scenario of arbitrary screenshot (Generalizable, Unseeable, Adaptable, Robust, Dynamic) and evaluate our method on these criteria. Extensive experiments demonstrate that ScreenGuard meets these five properties effectively, showcasing its superiority and broad practical applications.

Traditional video steganography methods are based on modifying the covert space for embedding, whereas we propose an innovative approach that embeds secret message within semantic feature for steganography during the video editing process. Although existing traditional video steganography methods excel in balancing security and capacity, they lack adequate robustness against common distortions in online social networks (OSNs). In this paper, we propose an end-to-end robust generative video steganography network (RoGVSN), which achieves visual editing by modifying semantic feature of videos to embed secret message. We exemplify the face-swapping scenario as an illustration to demonstrate the visual editing effects. Specifically, we devise an adaptive scheme to seamlessly embed secret messages into the semantic features of videos through fusion blocks. Extensive experiments demonstrate the superiority of our method in terms of robustness, extraction accuracy, visual quality, and capacity.

Generative steganography, a novel paradigm in information hiding, has garnered considerable attention for its potential to withstand steganalysis. However, existing generative steganography approaches suffer from the limited visual quality of generated images and are challenging to apply to lossy transmissions in real-world scenarios with unknown channel attacks. To address these issues, this paper proposes a novel robust generative image steganography scheme, facilitating zero-shot text-driven stego image generation without the need for additional training or fine-tuning. Specifically, we employ the popular Stable Diffusion model as the backbone generative network to establish a covert transmission channel. Our proposed framework overcomes the challenges of numerical instability and perturbation sensitivity inherent in diffusion models. Adhering to Kerckhoff’s principle, we propose a novel mapping module based on dual keys to enhance robustness and security under lossy transmission conditions. Experimental results showcase the superior performance of our method in terms of extraction accuracy, robustness, security, and image quality.

Previous researches on multimedia fake news detection include a series of complex feature extraction and fusion networks to gather useful information from the news. However, how cross-modal consistency relates to the fidelity of news and how features from different modalities affect the decision-making are still open questions. This paper presents a novel scheme of Bootstrapping Multi-view Representations (BMR) for fake news detection. Given a multi-modal news, we extract representations respectively from the views of the text, the image pattern and the image semantics. Improved Multi-gate Mixture-of-Expert networks (iMMoE) are proposed for feature refinement and fusion. Representations from each view are separately used to coarsely predict the fidelity of the whole news, and the multimodal representations are able to predict the cross-modal consistency. With the prediction scores, we reweigh each view of the representations and bootstrap them for fake news detection. Extensive experiments conducted on typical fake news detection datasets prove that BMR outperforms state-of-the-art schemes.

RAW files are the initial measurement of scene radiance widely used in most cameras, and the ubiquitously-used RGB images are converted from RAW data through Image Signal Processing (ISP) pipelines. Nowadays, digital images are risky of being nefariously manipulated. Inspired by the fact that innate immunity is the first line of body defense, we propose DRAW, a novel scheme of defending images against manipulation by protecting their sources, i.e., camera-shooted RAWs. Specifically, we design a lightweight Multi-frequency Partial Fusion Network (MPF-Net) friendly to devices with limited computing resources by frequency learning and partial feature fusion. It introduces invisible watermarks as protective signal into the RAW data. The protection capability can not only be transferred into the rendered RGB images regardless of the applied ISP pipeline, but also is resilient to post-processing operations such as blurring or compression. Once the image is manipulated, we can accurately identify the forged areas with a localization network. Extensive experiments on several famous RAW datasets, e.g., RAISE, FiveK and SIDD, indicate the effectiveness of our method. We hope that this technique can be used in future cameras as an option for image protection, which could effectively restrict image manipulation at the source.

Existing image cropping detection schemes ignore that recovering the cropped-out contents can unveil the purpose of the behaved cropping attack. This paper presents CLR-Net, a novel image protection scheme addressing the combined challenge of image Cropping Localization and Recovery. We first protect the original image by introducing imperceptible perturbations. Then, typical image post-processing attacks are simulated to erode the protected image. On the recipient’s side, we predict the cropping mask and recover the original image. Besides, we propose a novel Fine-Grained generative JPEG simulator (FG-JPEG) as well as a feature alignment network to improve the real-world robustness. Comprehensive experiments prove that the quality of the recovered image and the accuracy of crop localization are both satisfactory.

Image cropping can be maliciously used to manipulate the layout of an image and alter the underlying meaning. Previous image cropping detection schemes only predict whether an image has been cropped, ignoring which part of the image is cropped. This paper presents a novel robust watermarking network for image cropping localization. We train an anti-cropping processor (ACP) that embeds a watermark into a target image. The visually indistinguishable protected image is then posted on the social network instead of the original image. At the recipient’s side, ACP extracts the watermark from the attacked image, and we conduct feature matching on the original and extracted watermark to locate the position of the cropping. We further extend our scheme to detect tampering attacks on the attacked image, and a simple yet efficient method (JPEG-Mixup) is proposed that noticeably improves the generalization of JPEG robustness. We demonstrate that our scheme is the first to provide high-accuracy and robust image cropping localization.

The main purpose of this paper is to study different types of sampling formulas of quaternionic functions, which are bandlimited under various quaternion Fourier and linear canonical transforms. We show that the quaternionic bandlimited functions can be reconstructed from their samples as well as the samples of their derivatives and Hilbert transforms. In addition, the relationships among different types of sampling formulas under various transforms are discussed. First, if the quaternionic function is bandlimited to a rectangle that is symmetric about the origin, then the sampling formulas under various quaternion Fourier transforms are identical. If this rectangle is not symmetric about the origin, then the sampling formulas under various quaternion Fourier transforms are different from each other. Second, using the relationship between the two-sided quaternion Fourier transform and the linear canonical transform, we derive sampling formulas under various quaternion linear canonical transforms. Third, truncation errors of these sampling formulas are estimated. Finally, some simulations are provided to show how the sampling formulas can be used in applications.

Recent advances in Web services have made it practical to provide communication Web services to enable communication through SOA and package communication capability as services. This paper provides an appropriate implementation to deliver the multimedia conferencing communication components as Web services in order to be used simply by Web service clients in converged applications.

In this paper, we introduce the session initiation protocol (SIP) based multimedia conferencing on Internet, and mainly focus on the design and implementation for conferencing communication services model, such as SIP connection, session management, media control conferencing management, also we provide a prototype. Finally, we give the conclusions.

Service-oriented communication (SOC) is a new trend in the industry to enable communication through a service-oriented architecture (SOA) and thereby encapsulate communication capabilities as services. In this paper, we design the session initiation protocol (SIP) based multimedia conferencing communication services model, And mainly focus on formal analysis for BPEL based multimedia conferencing communication services orchestration and to guarantee the process correctness for such applications, and also providing an automated support for the formal analysis model of their behavior. Finally, we give the conclusions.