3D Gaussian splatting (3DGS) has demonstrated impressive 3D reconstruction performance with explicit scene representations. Given the widespread application of 3DGS in 3D reconstruction and generation tasks, there is an urgent need to protect the copyright of 3DGS assets. However, existing copyright protection techniques for 3DGS overlook the usability of 3D assets, posing challenges for practical deployment. Here we describe splats in splats, the first 3DGS steganography framework that embeds 3D content in 3DGS itself without modifying any attributes. To achieve this, we take a deep insight into spherical harmonics (SH) and devise an importance-graded SH coefficient encryption strategy to embed the hidden SH coefficients. Furthermore, we employ a convolutional autoencoder to establish a mapping between the original Gaussian primitives' opacity and the hidden Gaussian primitives' opacity. Extensive experiments indicate that our method significantly outperforms existing 3D steganography techniques, with 5.31% higher scene fidelity and 3x faster rendering speed, while ensuring security, robustness, and user experience.

3D Gaussian Splatting (3DGS) has emerged as a powerful representation for 3D scenes, widely adopted due to its exceptional efficiency and high-fidelity visual quality. Given the significant value of 3DGS assets, recent works have introduced specialized watermarking schemes to ensure copyright protection and ownership verification. However, can existing 3D Gaussian watermarking approaches genuinely guarantee robust protection of the 3D assets? In this paper, for the first time, we systematically explore and validate possible vulnerabilities of 3DGS watermarking frameworks. We demonstrate that conventional watermark removal techniques designed for 2D images do not effectively generalize to the 3DGS scenario due to the specialized rendering pipeline and unique attributes of each gaussian primitives. Motivated by this insight, we propose GSPure, the first watermark purification framework specifically for 3DGS watermarking representations. By analyzing view-dependent rendering contributions and exploiting geometrically accurate feature clustering, GSPure precisely isolates and effectively removes watermark-related Gaussian primitives while preserving scene integrity. Extensive experiments demonstrate that our GSPure achieves the best watermark purification performance, reducing watermark PSNR by up to 16.34dB while minimizing degradation to original scene fidelity with less than 1dB PSNR loss. Moreover, it consistently outperforms existing methods in both effectiveness and generalization.

High-speed vision tasks have long been a challenge in computer vision. Recently, the spike camera has shown great potential in these tasks due to its high temporal resolution. Unlike traditional cameras, it emits asynchronous spike signals to capture visual information. However, under low-light conditions, spike signals become highly sparse, and the sparse spike stream severely hinders the effectiveness of existing spike-based methods in high-speed scenarios. To address this challenge, we introduce SS2DS, the first deep learning framework that enhances sparse spike streams into dense spike streams. SS2DS first estimates the spike firing frequency within sparse streams. Subsequently, the spike firing frequency is enhanced by a neural network. Finally, SS2DS decodes the enhanced spike stream from the enhanced spike firing frequency sequence. SS2DS can adjust the temporal distribution of sparse spike streams and improve the performance degradation of existing methods in low-light and high-speed scenarios. To evaluate sparse spike stream enhancement, we construct both synthetic and real sparse spike stream datasets. By comparing the reconstruction results, enhanced spike streams achieve an average improvement of +0.78 MA, -18.42 BRISQUE, and -1.42 NIQE over sparse spike streams. Moreover, the enhanced spike streams also benefit other spike-based vision tasks, such as 3D reconstruction (+1.325 dB PSNR, +0.005 SSIM, and -0.01 LPIPS) and superresolution (+0.63 MA, -13.67 BRISQUE, and -1.28 NIQE).

The rise of wireless technologies has made the Internet of Things (IoT) ubiquitous, but the broadcast nature of wireless communications exposes IoT to authentication risks. Physical layer authentication (PLA) offers a promising solution by leveraging unique characteristics of wireless channels. As a common approach in PLA, hypothesis testing yields a theoretically optimal Neyman-Pearson (NP) detector, but its reliance on channel statistics limits its practicality in real-world scenarios. In contrast, deep learning-based PLA approaches are practical but tend to be not optimal. To address these challenges, we proposed a learning-based PLA scheme driven by hypothesis testing and conducted extensive simulations and experimental evaluations using Wi-Fi. Specifically, we incorporated conditional statistical models into the hypothesis testing framework to derive a theoretically optimal NP detector. Building on this, we developed LiteNP-Net, a lightweight neural network driven by the NP detector. Simulation results demonstrated that LiteNP-Net could approach the performance of the NP detector even without prior knowledge of the channel statistics. To further assess its effectiveness in practical environments, we deployed an experimental testbed using Wi-Fi IoT development kits in various real-world scenarios. Experimental results demonstrated that the LiteNP-Net outperformed the conventional correlation-based method as well as state-of-the-art Siamese-based methods.

3D Gaussian Splatting (3DGS) has been proven to exhibit exceptional performance in reconstructing 3D scenes. However, the effectiveness of 3DGS heavily relies on sharp images, and fulfilling this requirement presents challenges in real-world scenarios particularly when utilizing fast-moving cameras. This limitation severely constrains the practical application of 3DGS and may compromise the feasibility of real-time reconstruction. To mitigate these challenges, we proposed Spike Gaussian Splatting (SpikeGS), the first framework that integrates the Bayer-pattern spike streams into the 3DGS pipeline to reconstruct 3D scenes captured by a fast-moving high temporal color spike camera in one second. With accumulation rasterization, interval supervision, and a special designed pipeline, SpikeGS realizes continuous spatiotemporal perception while extracts detailed structure and texture from Bayer-pattern spike stream which is unstable and lacks details. Extensive experiments on both synthetic and real-world datasets demonstrate the superiority of SpikeGS compared with existing spike-based and deblur 3D scene reconstruction methods.

The Internet of Things (IoT) is ubiquitous thanks to the rapid development of wireless technologies. However, the broadcast nature of wireless transmissions results in great vulnerability to device authentication. Physical layer authentication emerges as a promising approach by exploiting the unique channel characteristics. However, a practical scheme applicable to dynamic channel variations is still missing. In this paper, we proposed a deep learning-based physical layer channel state information (CSI) authentication for mobile scenarios and carried out comprehensive simulation and experimental evaluation using IEEE 802.11n. Specifically, a synthetic training dataset was generated based on the WLAN TGn channel model and the autocorrelation and the distance correlation of the channel, which can significantly reduce the overhead of manually collecting experimental datasets. A convolutional neural network (CNN)-based Siamese network was exploited to learn the temporal and spatial correlation between the CSI pair and output a score to measure their similarity. We adopted a synergistic methodology involving both simulation and experimental evaluation. The experimental testbed consisted of WiFi IoT development kits and a few typical scenarios were specifically considered. Both simulation and experimental evaluation demonstrated excellent generalization performance of our proposed deep learning-based approach and excellent authentication performance. Demonstrated by our practical measurement results, our proposed scheme improved the area under the curve (AUC) by 0.03 compared to the fully connected network-based (FCN-based) Siamese model and by 0.06 compared to the correlation-based benchmark algorithm.

As software systems grow in complexity, scale, and update frequency, parallel fuzzing has become essential for mitigating the efficiency limitations of traditional fuzzing. Effective task allocation is vital in maximizing parallel fuzzing efficiency and has garnered significant attention. However, current strategies often neglect critical code areas, treating all regions uniformly and resulting in suboptimal exploration. To address the limitations of current approaches, we present FlexFuzz, a novel parallel fuzzing system. First, we identify the boundary basic blocks that connect covered and uncovered areas, dynamically adapting them as fuzzing progresses. Second, we introduce a boundary-sensitive task allocation scheme that assigns fuzzing tasks based on the identified boundary basic blocks and their potential for exploration. Finally, to ensure focused exploration, we implement a multi-target, distance-guided approach that directs each instance to concentrate on its relevant task area. We have implemented a prototype of FlexFuzz and comprehensively evaluated it against the state-of-the-art parallel fuzzing systems. Across standard benchmarks, FlexFuzz surpasses other parallel tools: it increases coverage by 20.09% over the next best tool (PAFL), and identifies 33.75% more vulnerabilities than the next best tool (AFL++).

As a neuromorphic sensor with high temporal resolution, spike cameras offer notable advantages over traditional cameras in high-speed vision applications such as high-speed optical estimation, depth estimation, and object tracking. Inspired by the success of the spike camera, we proposed Spike-NeRF, the first Neural Radiance Field derived from spike data, to achieve 3D reconstruction and novel viewpoint synthesis for high-speed scenes. Instead of the multi-view images at the same as time of NeRF, the inputs of Spike-NeRF are continuous spike streams captured by a moving spike camera in a very short time. To reconstruct a correct and stable 3D scene from high-frequency but unstable spike data, we devised spike masks along with a distinctive loss function. We evaluate our method qualitatively and quantitatively on several challenging synthetic scenes generated using Blender with the spike camera simulator. Our results demonstrate that Spike-NeRF produces more visually appealing results than the existing methods and the baseline we proposed in high-speed scenes. Our code is available at https://github.com/yijiaguo02/SpikeNerf

Spike cameras, with their exceptional temporal resolution, are revolutionizing high-speed visual applications. Large-scale synthetic datasets have significantly accelerated the development of these cameras, particularly in reconstruction and optical flow. However, current synthetic datasets for spike cameras lack sophistication. Addressing this gap, we introduce SCSim, a novel and more realistic spike camera simulator with a comprehensive noise model. SCSim is adept at autonomously generating driving scenarios and synthesizing corresponding spike streams. To enhance the fidelity of these streams, we’ve developed a comprehensive noise model tailored to the unique circuitry of spike cameras. Our evaluations demonstrate that SCSim outperforms existing simulation methods in generating authentic spike streams. Crucially, SCSim simplifies the creation of datasets, thereby greatly advancing spike-based visual tasks like reconstruction. Our project refers to https://github.com/Acnext/SCSim.

We proposed Precomputed Radiance Transfer of Gaussian Splats (PRTGS), a real-time high-quality relighting method for Gaussian splats in low-frequency lighting environments that captures soft shadows and interreflections by precomputing 3D Gaussian splats' radiance transfer. Existing studies have demonstrated that 3D Gaussian splatting (3DGS) outperforms neural fields in efficiency for dynamic lighting scenarios. However, the current relighting method based on 3DGS is still struggling to compute high-quality shadow and indirect illumination in real time for dynamic light, leading to unrealistic rendering results. We solve this problem by precomputing the expensive transport simulations required for complex transfer functions like shadowing, the resulting transfer functions are represented as dense sets of vectors or matrices for every Gaussian splat. We introduce distinct precomputing methods tailored for training and rendering stages, along with unique ray tracing and indirect lighting precomputation techniques for 3D Gaussian splats to accelerate training speed and compute accurate indirect lighting related to environment light. Experimental analyses demonstrate that our approach achieves state-of-the-art visual quality while maintaining competitive training times and importantly allows high-quality real-time (30+ fps) relighting for dynamic light and relatively complex scenes at 1080p resolution.

The Internet of Things (IoT) is ubiquitous thanks to the rapid development of wireless technology. However, the broadcast nature of wireless transmission results in great challenges to the security authentication for large-scale IoT. In this paper, we propose a novel physical layer authentication approach for mobile scenarios employing deep learning and channel state information (CSI). Specifically, the convolution neural network (CNN) is designed to learn the temporal and spatial similarity between CSIs and output a score to measure the difference between the input CSIs. Device authentication is achieved by comparing the score to an empirically obtained threshold. We build a WiFi-based testbed and carry out a comprehensive experimental evaluation. The performance of using the CSI magnitude and real & imaginary parts is compared. The effect of the distance between legitimate and rogue devices on authentication performance is studied. The generalization performance of the CNN model in different test scenarios is also evaluated. Experiment results demonstrate the effectiveness of the proposed CNN-based authentication over conventional correlation-based authentication schemes.

Nowadays, Federated Learning (FL) over Internet of Medical Things (IoMT) devices has become a current research hotspot. As a new architecture, FL can well protect the data privacy of IoMT devices, but the security of neural network model transmission can not be guaranteed. On the other hand, the sizes of current popular neural network models are usually relatively extensive, and how to deploy them on the IoMT devices has become a challenge. One promising approach to these problems is to reduce the network scale by quantizing the parameters of the neural networks, which can greatly improve the security of data transmission and reduce the transmission cost. In the previous literature, the fixed-point quantizer with stochastic rounding has been shown to have better performance than other quantization methods. However, how to design such quantizer to achieve the minimum square quantization error is still unknown. In addition, how to apply this quantizer in the FL framework also needs investigation. To address these questions, in this paper, we propose FedMSQE - Federated Learning with Minimum Square Quantization Error, that achieves the smallest quantization error for each individual client in the FL setting. Through numerical experiments in both single-node and FL scenarios, we prove that our proposed algorithm can achieve higher accuracy and lower quantization error than other quantization methods.

Vehicular ad hoc networks (VANETs) is one of the most promising approaches for the Intelligent Transportation Systems (ITS). With the rapid increase in the amount of traffic data, deep learning based algorithms have been used extensively in VANETs. The recently proposed federated learning is an attractive candidate for collaborative machine learning where instead of transferring a plethora of data to a centralized server, all clients train their respective local models and upload them to the server for model aggregation. Model quantization is an effective approach to address the communication efficiency issue in federated learning, and yet existing studies largely assume homogeneous quantization for all clients. However, in reality, clients are predominantly heterogeneous, where they support different quantization precision levels. In this work, we propose FedDO – Federated Learning with Double Optimization. Minimizing the drift term in the convergence analysis, which is a weighted sum of squared quantization errors (SQE) over all clients, leads to a double optimization at both clients and server sides. In particular, each client adopts a fully distributed, instantaneous (per learning round) and individualized (per client) quantization scheme that minimizes its own squared quantization error, and the server computes the aggregation weights that minimize the weighted sum of squared quantization errors over all clients. We show via numerical experiments that the minimal-SQE quantizer has a better performance than a widely adopted linear quantizer for federated learning. We also demonstrate the performance advantages of FedDO over the vanilla FedAvg with standard equal weights and linear quantization.

As a forerunner in 5G ecosystem construction and industry application, Narrowband Internet of Things (NB-IoT) will be inevitably coexisting with legacy Long-Term Evolution (LTE) system. To meet the key performance indicators defined in 5G standard, it is imperative for NB-IoT to mitigate the LTE interference. By virtue of the strong temporal correlation of NB-IoT signal, this paper develops a sparse recovery algorithm based on K-means clustering, which iteratively clusters the correlation coefficients between the measurement vector and each column of observation matrix. Compared with the ideal case without interference, extensive simulation results demonstrate the effective recovery of the proposed algorithm.