Diffusion Probabilistic Models (DPMs) have shown a powerful capacity of generating high-quality image samples. Recently, diffusion autoencoders (Diff-AE) have been proposed to explore DPMs for representation learning via autoencoding. Their key idea is to jointly train an encoder for discovering meaningful representations from images and a conditional DPM as the decoder for reconstructing images. Considering that training DPMs from scratch will take a long time and there have existed numerous pre-trained DPMs, we propose \textbf{P}re-trained \textbf{D}PM \textbf{A}uto\textbf{E}ncoding (\textbf{PDAE}), a general method to adapt existing pre-trained DPMs to the decoders for image reconstruction, with better training efficiency and performance than Diff-AE. Specifically, we find that the reason that pre-trained DPMs fail to reconstruct an image from its latent variables is due to the information loss of forward process, which causes a gap between their predicted posterior mean and the true one. From this perspective, the classifier-guided sampling method can be explained as computing an extra mean shift to fill the gap, reconstructing the lost class information in samples. These imply that the gap corresponds to the lost information of the image, and we can reconstruct the image by filling the gap. Drawing inspiration from this, we employ a trainable model to predict a mean shift according to encoded representation and train it to fill as much gap as possible, in this way, the encoder is forced to learn as much information as possible from images to help the filling. By reusing a part of network of pre-trained DPMs and redesigning the weighting scheme of diffusion loss, PDAE can learn meaningful representations from images efficiently. Extensive experiments demonstrate the effectiveness, efficiency and flexibility of PDAE.

The deep learning community has witnessed an exponentially growing interest in self-supervised learning (SSL). However, it still remains unexplored how to build a framework for learning useful representations of raw music waveforms in a self-supervised manner. In this work, we design Music2Vec, a framework exploring different SSL algorithmic components and tricks for music audio recordings. Our model achieves comparable results to the state-of-the-art (SOTA) music SSL model Jukebox, despite being significantly smaller with less than 2% of parameters of the latter. The model will be released on Huggingface(Please refer to: https://huggingface.co/m-a-p/music2vec-v1)

对于单眼360图像，深度估计是一个具有挑战性的，因为失真沿纬度增加。为了感知失真，现有方法致力于设计深层且复杂的网络体系结构。在本文中，我们提供了一种新的观点，该视角为360图像构建了可解释且稀疏的表示形式。考虑到几何结构在深度估计中的重要性，我们利用Contourlet变换来捕获光谱域中的显式几何提示，并将其与空间域中的隐含提示集成在一起。具体而言，我们提出了一个由卷积神经网络和Contourlet变换分支组成的神经轮廓网络。在编码器阶段，我们设计了一个空间光谱融合模块，以有效融合两种类型的提示。与编码器相反，我们采用了逆向方形变换，并通过学习的低通子带和带通道的定向子带来构成解码器中的深度。在三个流行的全景图像数据集上进行的实验表明，所提出的方法的表现优于最先进的方案，其收敛速度更快。代码可在https://github.com/zhijieshen-bjtu/neural-contourlet-network-for-mode上找到。

最近，基于水平表示的全景语义分割方法优于基于投影的解决方案，因为可以通过在垂直方向上压缩球形数据来有效地消除畸变。但是，这些方法忽略了之前的失真分布，并且仅限于不平衡的接收场，例如，接收场在垂直方向上足够，并且在水平方向上不足。不同的是，沿另一个方向压缩的垂直表示可以提供隐式失真先验，并扩大水平接收场。在本文中，我们结合了两种不同的表示，并从互补的角度提出了一种新颖的360 {\ deg}语义分割解决方案。我们的网络包括三个模块：特征提取模块，一个双向压缩模块和一个集合解码模块。首先，我们从Panorama提取多尺度功能。然后，设计一个双向压缩模块，将特征压缩为两个互补的低维表示，这些表示提供了内容感知和失真。此外，为了促进双向特征的融合，我们在合奏解码模块中设计了独特的自我蒸馏策略，以增强不同特征的相互作用并进一步提高性能。实验结果表明，我们的方法的表现优于最先进的解决方案，在定量评估上至少提高了10 \％的改进，同时显示出视觉外观上最佳性能。

现有的全景深度估计方法基于卷积神经网络（CNN）的重点是消除全景畸变，由于CNN中的固定接受场而无法有效地感知全景结构。本文提出了全景变压器（名为PanoFormer），以估计全景图像中的深度，并带有球形域，可学习的令牌流和全景特定指标的切线斑块。特别是，我们将球形切线结构域上的斑块划分为令牌，以减少全景畸变的负面影响。由于几何结构对于深度估计是必不可少的，因此自我发项式模块通过额外的可学习令牌流重新设计。此外，考虑到球形域的特征，我们提出了两个全景特异性指标，以全面评估全景深度估计模型的性能。广泛的实验表明，我们的方法显着优于最先进的方法（SOTA）方法。此外，可以有效地扩展提出的方法以求解语义全景分割，这是类似的Pixel2像素任务。代码将可用。

随着深度学习技术的快速发展和计算能力的提高，深度学习已广泛应用于高光谱图像（HSI）分类领域。通常，深度学习模型通常包含许多可训练参数，并且需要大量标记的样品来实现最佳性能。然而，关于HSI分类，由于手动标记的难度和耗时的性质，大量标记的样本通常难以获取。因此，许多研究工作侧重于建立一个少数标记样本的HSI分类的深层学习模型。在本文中，我们专注于这一主题，并对相关文献提供系统审查。具体而言，本文的贡献是双重的。首先，相关方法的研究进展根据学习范式分类，包括转移学习，积极学习和少量学习。其次，已经进行了许多具有各种最先进的方法的实验，总结了结果以揭示潜在的研究方向。更重要的是，虽然深度学习模型（通常需要足够的标记样本）和具有少量标记样本的HSI场景之间存在巨大差距，但是通过深度学习融合，可以很好地表征小样本集的问题方法和相关技术，如转移学习和轻量级模型。为了再现性，可以在HTTPS://github.com/shuguoj/hsi-classification中找到纸张中评估的方法的源代码.git。

Deep learning (DL) has become a driving force and has been widely adopted in many domains and applications with competitive performance. In practice, to solve the nontrivial and complicated tasks in real-world applications, DL is often not used standalone, but instead contributes as a piece of gadget of a larger complex AI system. Although there comes a fast increasing trend to study the quality issues of deep neural networks (DNNs) at the model level, few studies have been performed to investigate the quality of DNNs at both the unit level and the potential impacts on the system level. More importantly, it also lacks systematic investigation on how to perform the risk assessment for AI systems from unit level to system level. To bridge this gap, this paper initiates an early exploratory study of AI system risk assessment from both the data distribution and uncertainty angles to address these issues. We propose a general framework with an exploratory study for analyzing AI systems. After large-scale (700+ experimental configurations and 5000+ GPU hours) experiments and in-depth investigations, we reached a few key interesting findings that highlight the practical need and opportunities for more in-depth investigations into AI systems.

We present a novel method to provide efficient and highly detailed reconstructions. Inspired by wavelets, our main idea is to learn a neural field that decompose the signal both spatially and frequency-wise. We follow the recent grid-based paradigm for spatial decomposition, but unlike existing work, encourage specific frequencies to be stored in each grid via Fourier features encodings. We then apply a multi-layer perceptron with sine activations, taking these Fourier encoded features in at appropriate layers so that higher-frequency components are accumulated on top of lower-frequency components sequentially, which we sum up to form the final output. We demonstrate that our method outperforms the state of the art regarding model compactness and efficiency on multiple tasks: 2D image fitting, 3D shape reconstruction, and neural radiance fields.

Recent years have witnessed an astonishing explosion in the evolution of mobile applications powered by AI technologies. The rapid growth of AI frameworks enables the transition of AI technologies to mobile devices, significantly prompting the adoption of AI apps (i.e., apps that integrate AI into their functions) among smartphone devices. In this paper, we conduct the most extensive empirical study on 56,682 published AI apps from three perspectives: dataset characteristics, development issues, and user feedback and privacy. To this end, we build an automated AI app identification tool, AI Discriminator, that detects eligible AI apps from 7,259,232 mobile apps. First, we carry out a dataset analysis, where we explore the AndroZoo large repository to identify AI apps and their core characteristics. Subsequently, we pinpoint key issues in AI app development (e.g., model protection). Finally, we focus on user reviews and user privacy protection. Our paper provides several notable findings. Some essential ones involve revealing the issue of insufficient model protection by presenting the lack of model encryption, and demonstrating the risk of user privacy data being leaked. We published our large-scale AI app datasets to inspire more future research.

The Modboat is a low-cost, underactuated, modular robot capable of surface swimming, docking to other modules, and undocking from them using only a single motor and two passive flippers. Undocking is achieved by causing intentional self-collision between the tails of neighboring modules in certain configurations; this becomes a challenge, however, when collective swimming as one connected component is desirable. Prior work has developed controllers that turn arbitrary configurations of docked Modboats into steerable vehicles, but they cannot counteract lateral forces and disturbances. In this work we present a centralized control strategy to create holonomic vehicles out of arbitrary configurations of docked Modboats using an iterative potential-field based search. We experimentally demonstrate that our controller performs well and can control surge and sway velocities and yaw angle simultaneously.