本文提出了一种新的3D形状生成方法,从而在小波域中的连续隐式表示上实现了直接生成建模。具体而言,我们提出了一个带有一对粗糙和细节系数的紧凑型小波表示,通过截短的签名距离函数和多尺度的生物联盟波波隐式表示3D形状,并制定了一对神经网络:基于生成器基于扩散模型的生成器以粗糙系数的形式产生不同的形状;以及一个细节预测因子,以进一步生成兼容的细节系数量,以丰富具有精细结构和细节的生成形状。定量和定性实验结果都表现出我们的方法在产生具有复杂拓扑和结构,干净表面和细节的多样化和高质量形状方面的优势,超过了最先进的模型的3D生成能力。
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由于没有大型配对的文本形状数据,这两种方式之间的大量语义差距以及3D形状的结构复杂性,因此文本指导的3D形状生成仍然具有挑战性。本文通过引入2D图像作为垫脚石来连接两种方式并消除对配对的文本形状数据的需求,提出了一个名为“图像”的新框架,称为“垫脚石”(ISS)。我们的关键贡献是一种两阶段的功能空间对准方法,它通过利用具有多视图Supperions的预训练的单视重构造(SVR)模型来映射剪辑功能以形成形状:首先将剪辑图像剪辑剪辑功能到详细信息 - SVR模型中的丰富形状空间,然后将剪辑文本功能映射到形状空间,并通过鼓励输入文本和渲染图像之间的剪辑一致性来优化映射。此外,我们制定了一个文本制定的形状样式化模块,以用新颖的纹理打扮出输出形状。除了从文本上生成3D Shape生成的现有作品外,我们的新方法是在不需要配对的文本形状数据的情况下创建形状的一般性。实验结果表明,我们的方法在忠诚度和与文本一致性方面优于最先进的和我们的基线。此外,我们的方法可以通过逼真的和幻想结构和纹理对生成的形状进行样式化。
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本文介绍了一个名为DTNET的新颖框架,用于3D网格重建和通过Distangled Tostology生成。除了以前的工作之外,我们还学习一个特定于每个输入的拓扑感知的神经模板,然后将模板变形以重建详细的网格,同时保留学习的拓扑。一个关键的见解是将复杂的网格重建分解为两个子任务:拓扑配方和形状变形。多亏了脱钩,DT-NET隐含地学习了潜在空间中拓扑和形状的分离表示。因此,它可以启用新型的脱离控件,以支持各种形状生成应用,例如,将3D对象的拓扑混合到以前的重建作品无法实现的3D对象的拓扑结构。广泛的实验结果表明,与最先进的方法相比,我们的方法能够产生高质量的网格,尤其是具有不同拓扑结构。
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点云上采样是为了使从3D传感器获得的稀疏点集致密,从而为基础表面提供了密度的表示。现有方法将输入点划分为小贴片,并分别对每个贴片进行整理,但是,忽略了补丁之间的全局空间一致性。在本文中,我们提出了一种新颖的方法PC $^2 $ -PU,该方法探讨了贴片对点和点对点相关性,以实现更有效和强大的点云上采样。具体而言,我们的网络有两个吸引人的设计:(i)我们将相邻的补丁作为补充输入来补偿单个补丁中的损失结构信息,并引入一个补丁相关模块以捕获补丁之间的差异和相似性。 (ii)在增强每个贴片的几何形状后,我们进一步引入了一个点相关模块,以揭示每个贴片内部的关系以维持局部空间一致性。对合成和真实扫描数据集进行的广泛实验表明,我们的方法超过了以前的上采样方法,尤其是在嘈杂的输入中。代码和数据位于\ url {https://github.com/chenlongwhu/pc2-pu.git}。
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图级表示在各种现实世界中至关重要,例如预测分子的特性。但是实际上,精确的图表注释通常非常昂贵且耗时。为了解决这个问题,图形对比学习构造实例歧视任务,将正面对(同一图的增强对)汇总在一起,并将负面对(不同图的增强对)推开,以进行无监督的表示。但是,由于为了查询,其负面因素是从所有图中均匀抽样的,因此现有方法遭受关键采样偏置问题的损失,即,否定物可能与查询具有相同的语义结构,从而导致性能降解。为了减轻这种采样偏见问题,在本文中,我们提出了一种典型的图形对比度学习(PGCL)方法。具体而言,PGCL通过将语义相似的图形群群归为同一组的群集数据的基础语义结构,并同时鼓励聚类的一致性,以实现同一图的不同增强。然后给出查询,它通过从与查询群集不同的群集中绘制图形进行负采样,从而确保查询及其阴性样本之间的语义差异。此外,对于查询,PGCL根据其原型(集群质心)和查询原型之间的距离进一步重新重新重新重新重新享受其负样本,从而使那些具有中等原型距离的负面因素具有相对较大的重量。事实证明,这种重新加权策略比统一抽样更有效。各种图基准的实验结果证明了我们的PGCL比最新方法的优势。代码可在https://github.com/ha-lins/pgcl上公开获取。
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In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
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Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.
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Automatic music generation with artificial intelligence typically requires a large amount of data which is hard to obtain for many less common genres and musical instruments. To tackle this issue, we present ongoing work and preliminary findings on the possibility for deep models to transfer knowledge from language to music, by finetuning large language models pre-trained on a massive text corpus on only hundreds of MIDI files of drum performances. We show that by doing so, one of the largest, state-of-the-art models (GPT3) is capable of generating reasonable drum grooves, while models that are not pre-trained (Transformer) shows no such ability beyond naive repetition. Evaluating generated music is a challenging task, more so is evaluating drum grooves with little precedence in literature. Hence, we propose a tailored structural evaluation method and analyze drum grooves produced by GPT3 compared to those played by human professionals, exposing the strengths and weaknesses of such generation by language-to-music transfer. Our findings suggest that language-to-music transfer learning with large language models is viable and promising.
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Few Shot Instance Segmentation (FSIS) requires models to detect and segment novel classes with limited several support examples. In this work, we explore a simple yet unified solution for FSIS as well as its incremental variants, and introduce a new framework named Reference Twice (RefT) to fully explore the relationship between support/query features based on a Transformer-like framework. Our key insights are two folds: Firstly, with the aid of support masks, we can generate dynamic class centers more appropriately to re-weight query features. Secondly, we find that support object queries have already encoded key factors after base training. In this way, the query features can be enhanced twice from two aspects, i.e., feature-level and instance-level. In particular, we firstly design a mask-based dynamic weighting module to enhance support features and then propose to link object queries for better calibration via cross-attention. After the above steps, the novel classes can be improved significantly over our strong baseline. Additionally, our new framework can be easily extended to incremental FSIS with minor modification. When benchmarking results on the COCO dataset for FSIS, gFSIS, and iFSIS settings, our method achieves a competitive performance compared to existing approaches across different shots, e.g., we boost nAP by noticeable +8.2/+9.4 over the current state-of-the-art FSIS method for 10/30-shot. We further demonstrate the superiority of our approach on Few Shot Object Detection. Code and model will be available.
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Graph Neural Networks (GNNs) have shown satisfying performance on various graph learning tasks. To achieve better fitting capability, most GNNs are with a large number of parameters, which makes these GNNs computationally expensive. Therefore, it is difficult to deploy them onto edge devices with scarce computational resources, e.g., mobile phones and wearable smart devices. Knowledge Distillation (KD) is a common solution to compress GNNs, where a light-weighted model (i.e., the student model) is encouraged to mimic the behavior of a computationally expensive GNN (i.e., the teacher GNN model). Nevertheless, most existing GNN-based KD methods lack fairness consideration. As a consequence, the student model usually inherits and even exaggerates the bias from the teacher GNN. To handle such a problem, we take initial steps towards fair knowledge distillation for GNNs. Specifically, we first formulate a novel problem of fair knowledge distillation for GNN-based teacher-student frameworks. Then we propose a principled framework named RELIANT to mitigate the bias exhibited by the student model. Notably, the design of RELIANT is decoupled from any specific teacher and student model structures, and thus can be easily adapted to various GNN-based KD frameworks. We perform extensive experiments on multiple real-world datasets, which corroborates that RELIANT achieves less biased GNN knowledge distillation while maintaining high prediction utility.
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