Cancer has become a leading cause of death worldwide, making the development of intelligent and automatic whole slide image (WSI) analysis tools crucial for diagnosis and treatment decision-making. However, the gigapixel size of WSIs poses significant challenges for annotation and analysis, motivating researchers to develop both label- and computational-efficient algorithms. While existing instance-based methods have shown promise in computational efficiency and patch-wise prediction, they often struggle with classification performance and lesion localization capabilities on pathological images. In this paper, we delve into the limitations of current instance-based approaches and attribute such inferior performance to (i) the overcontribution of normal patches and (ii) the absence of contextual information. To this end, we propose a simple yet effective logit-based log-sum-exp aggregator to modulate the contribution of normal patches and highlight the tumorous patches' contribution in the slide-wise prediction, and introduce a context-aware feature extraction module to capture the contextual patterns from neighborhood patches. Our method based on the above two components showcases the superior classification performance and lesion localization ability with low computational complexity on CAMELYON16, TCGA-NSCLC, and BRACS compared to existing methods.

As 4D extensions of 3D Gaussian Splatting (4D-GS) emerge as groundbreaking techniques for dynamic scene reconstruction and novel view synthesis in robotics and computer vision, ensuring the security and trustworthiness of these assets becomes crucial. While steganography has advanced significantly in 2D and 3D media, existing methods are inadequate for the complex, dynamic nature of 4D-GS representations. To address this gap, we propose Hide-in-Motion, a novel 4D steganography method for hiding information through deformation in Gaussian splatting. Our approach introduces a composite attribute and a Decouple Feature Field for coarse-to-fine deformation modeling and embedding implicit information, along with an Opacity-Guided Adaptive strategy. Hide-in-Motion overcomes the limitations of previous techniques, enhancing both the robustness of embedded information and the quality of 4D reconstruction. Extensive evaluations demonstrate that our method successfully embeds and recovers implicit information across various modalities while maintaining high rendering quality in dynamic scenes. This work not only advances copyright protection and secure data transmission for 4D assets but also paves the way for enhancing the security and integrity of 4D digital assets. Code is available at https://github.com/CUHK-AIM-Group/Hide-in-Motion.

Image registration is a fundamental medical image analysis task, and a wide variety of approaches have been proposed. However, only a few studies have comprehensively compared medical image registration approaches on a wide range of clinically relevant tasks. This limits the development of registration methods, the adoption of research advances into practice, and a fair benchmark across competing approaches. The Learn2Reg challenge addresses these limitations by providing a multi-task medical image registration data set for comprehensive characterisation of deformable registration algorithms. A continuous evaluation will be possible at https://learn2reg.grand-challenge.org. Learn2Reg covers a wide range of anatomies (brain, abdomen, and thorax), modalities (ultrasound, CT, MR), availability of annotations, as well as intra- and inter-patient registration evaluation. We established an easily accessible framework for training and validation of 3D registration methods, which enabled the compilation of results of over 65 individual method submissions from more than 20 unique teams. We used a complementary set of metrics, including robustness, accuracy, plausibility, and runtime, enabling unique insight into the current state-of-the-art of medical image registration. This paper describes datasets, tasks, evaluation methods and results of the challenge, as well as results of further analysis of transferability to new datasets, the importance of label supervision, and resulting bias. While no single approach worked best across all tasks, many methodological aspects could be identified that push the performance of medical image registration to new state-of-the-art performance. Furthermore, we demystified the common belief that conventional registration methods have to be much slower than deep-learning-based methods.