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Dequan Jin

Publications and source records attributed to Dequan Jin.

3 recordsLinked to original sources

LINGO: Latent Initialization and Gradient Optimization for Sparse-view X-ray Novel View Synthesis and CT Reconstruction with 3D Gaussian Splatting

In novel view synthesis and Computed Tomography (CT) reconstruction with sparse-view X-ray imaging, insufficient angular coverage leads to structural ambiguity and accumulated noise. Integrating 3D Gaussian Splatting (3DGS) with X-ray absorption physics can achieve promising results, but it suffers from noisy initialization, positional insensitivity, and weak gradients in low-density regions. In this paper, we propose a unified Latent Initialization and Gradient Optimization (LINGO) framework to address these issues. LINGO combines latent mask-space initialization with dynamic gradient optimization to improve point cloud structural completeness while accelerating training. It constructs voxel-level 3D filters from X-ray masks to robustly suppress background noise and provide reliable geometric priors. By employing an adaptive voxel scaling strategy and dynamically scaling loss, LINGO can adjust spatial resolution and explicitly amplify gradients in low-density structures. To evaluate the quality of initialization, we introduce the Initialization Point Cloud Structural Deviation (IPSD) metric. Experiments on the X3D dataset indicate that for the novel view synthesis task, LINGO improves the Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index (SSIM) by an average of 0.72 and 0.0039, respectively, over baselines under identical sparse-view settings, achieving comparable reconstruction quality within 5k steps to state-of-the-art models typically trained with 30k iterations. For the CT reconstruction task, LINGO also demonstrates consistent improvements, with average PSNR and SSIM gains of 0.36 and 0.0134. These results highlight LINGO's effectiveness in both accelerating training and enhancing reconstruction quality across different sparse-view imaging scenarios.

cs.CV

ViTNF: Leveraging Neural Fields to Boost Vision Transformers in Generalized Category Discovery

Generalized category discovery (GCD) is a highly popular task in open-world recognition, aiming to identify unknown class samples using known class data. By leveraging pre-training, meta-training, and fine-tuning, ViT achieves excellent few-shot learning capabilities. Its MLP head is a feedforward network, trained synchronously with the entire network in the same process, increasing the training cost and difficulty without fully leveraging the power of the feature extractor. This paper proposes a new architecture by replacing the MLP head with a neural field-based one. We first present a new static neural field function to describe the activity distribution of the neural field and then use two static neural field functions to build an efficient few-shot classifier. This neural field-based (NF) classifier consists of two coupled static neural fields. It stores the feature information of support samples by its elementary field, the known categories by its high-level field, and the category information of support samples by its cross-field connections. We replace the MLP head with the proposed NF classifier, resulting in a novel architecture ViTNF, and simplify the three-stage training mode by pre-training the feature extractor on source tasks and training the NF classifier with support samples in meta-testing separately, significantly reducing ViT's demand for training samples and the difficulty of model training. To enhance the model's capability in identifying new categories, we provide an effective algorithm to determine the lateral interaction scale of the elementary field. Experimental results demonstrate that our model surpasses existing state-of-the-art methods on CIFAR-100, ImageNet-100, CUB-200, and Standard Cars, achieving dramatic accuracy improvements of 19\% and 16\% in new and all classes, respectively, indicating a notable advantage in GCD.

cs.CV

RoNFA: Robust Neural Field-based Approach for Few-Shot Image Classification with Noisy Labels

In few-shot learning (FSL), the labeled samples are scarce. Thus, label errors can significantly reduce classification accuracy. Since label errors are inevitable in realistic learning tasks, improving the robustness of the model in the presence of label errors is critical. This paper proposes a new robust neural field-based image approach (RoNFA) for few-shot image classification with noisy labels. RoNFA consists of two neural fields for feature and category representation. They correspond to the feature space and category set. Each neuron in the field for category representation (FCR) has a receptive field (RF) on the field for feature representation (FFR) centered at the representative neuron for its category generated by soft clustering. In the prediction stage, the range of these receptive fields adapts according to the neuronal activation in FCR to ensure prediction accuracy. These learning strategies provide the proposed model with excellent few-shot learning capability and strong robustness against label noises. The experimental results on real-world FSL datasets with three different types of label noise demonstrate that the proposed method significantly outperforms state-of-the-art FSL methods. Its accuracy obtained in the presence of noisy labels even surpasses the results obtained by state-of-the-art FSL methods trained on clean support sets, indicating its strong robustness against noisy labels.

cs.CV