The goal of community search in heterogeneous information networks (HINs) is to identify a set of closely related target nodes that includes a query target node. In practice, a size constraint is often imposed due to limited resources, which has been overlooked by most existing HIN community search works. In this paper, we introduce the size-bounded community search problem to HIN data. Specifically, we propose a refined (k, P)-truss model to measure community cohesiveness, aiming to identify the most cohesive community of size s that contains the query node. We prove that this problem is NP-hard. To solve this problem, we develop a novel B\&B framework that efficiently generates target node sets of size s. We then tailor novel bounding, branching, total ordering, and candidate reduction optimisations, which enable the framework to efficiently lead to an optimum result. We also design a heuristic algorithm leveraging structural properties of HINs to efficiently obtain a high-quality initial solution, which serves as a global lower bound to further enhance the above optimisations. Building upon these, we propose two exact algorithms that enumerate combinations of edges and nodes, respectively. Extensive experiments on real-world datasets demonstrate the effectiveness and efficiency of the proposed methods.

Graph data has been widely applied due to its powerful expressive capabilities. The release of raw graph data without preprocessing may lead to privacy information leakage. Thus, generating privacy-protected graphs is necessary for data analysis. Current privacy protection methods in graphs focus on securing attributes like degree distribution, triangle counts, and node information, but they often overlook the need to protect user group relationships. Additionally, some privacy-preserving graph publishing methods introduce significant noise due to the chosen graph generation techniques and the points at which noise is added. This paper aims to propose an effective graph synthesis algorithm by using differential privacy named DPCAG (Differentially Private Community Affiliation Graph Generation Model) for protecting user group relationships. Firstly, it is observed that there are numerous small probabilities in the adjacency matrix D generated by the affiliation matrix F, directly utilizing it to construct graph G would result in the generation of a substantial number of redundant edges. Therefore, we introduce a generating threshold theta to filter out unnecessary edges. Secondly, to achieve a better balance between data availability and the level of privacy protection, two budget allocation schemes are designed based on the introduction of k-truss to describe the tightness of group relationships. Lastly, we demonstrate the proposed model satisfies differential privacy mathematically and the effectiveness of DPCAG is validated using four real graph datasets.

Choreography refers to creation of dance motions according to both music and dance knowledge, where the created dances should be style-specific and consistent. However, most of the existing methods generate dances using the given music as the only reference, lacking the stylized dancing knowledge, namely, the flag motion patterns contained in different styles. Without the stylized prior knowledge, these approaches are not promising to generate controllable style or diverse moves for each dance style, nor new dances complying with stylized knowledge. To address this issue, we propose a novel music-to-dance generation framework guided by style embedding, considering both input music and stylized dancing knowledge. These style embeddings are learnt representations of style-consistent kinematic abstraction of reference dance videos, which can act as controllable factors to impose style constraints on dance generation in a latent manner. Hence, we can make the style embedding fit into any given style while allowing the flexibility to generate new compatible dance moves by modifying the style embedding according to the learnt representations of a certain style. We are the first to achieve knowledge-driven style control in dance generation tasks. To support this study, we build a large multi-style music-to-dance dataset referred to as I-Dance. The qualitative and quantitative evaluations demonstrate the advantage of the proposed framework, as well as the ability to synthesize diverse moves under a dance style directed by style embedding.

Video Compression Artifact Reduction aims to reduce the artifacts caused by video compression algorithms and improve the quality of compressed video frames. The critical challenge in this task is to make use of the redundant high-quality information in compressed frames for compensation as much as possible. Two important possible compensations: Motion compensation and global context, are not comprehensively considered in previous works, leading to inferior results. The key idea of this paper is to fuse the motion compensation and global context together to gain more compensation information to improve the quality of compressed videos. Here, we propose a novel Spatio-Temporal Compensation Fusion (STCF) framework with the Parallel Swin-CNN Fusion (PSCF) block, which can simultaneously learn and merge the motion compensation and global context to reduce the video compression artifacts. Specifically, a temporal self-attention strategy based on shifted windows is developed to capture the global context in an efficient way, for which we use the Swin transformer layer in the PSCF block. Moreover, an additional Ada-CNN layer is applied in the PSCF block to extract the motion compensation. Experimental results demonstrate that our proposed STCF framework outperforms the state-of-the-art methods up to 0.23dB (27% improvement) on the MFQEv2 dataset.

Semantic image editing provides users with a flexible tool to modify a given image guided by a corresponding segmentation map. In this task, the features of the foreground objects and the backgrounds are quite different. However, all previous methods handle backgrounds and objects as a whole using a monolithic model. Consequently, they remain limited in processing content-rich images and suffer from generating unrealistic objects and texture-inconsistent backgrounds. To address this issue, we propose a novel paradigm, Semantic Image Editing by Disentangling Object and Background (SIEDOB), the core idea of which is to explicitly leverages several heterogeneous subnetworks for objects and backgrounds. First, SIEDOB disassembles the edited input into background regions and instance-level objects. Then, we feed them into the dedicated generators. Finally, all synthesized parts are embedded in their original locations and utilize a fusion network to obtain a harmonized result. Moreover, to produce high-quality edited images, we propose some innovative designs, including Semantic-Aware Self-Propagation Module, Boundary-Anchored Patch Discriminator, and Style-Diversity Object Generator, and integrate them into SIEDOB. We conduct extensive experiments on Cityscapes and ADE20K-Room datasets and exhibit that our method remarkably outperforms the baselines, especially in synthesizing realistic and diverse objects and texture-consistent backgrounds. Code is available at https://github.com/WuyangLuo/SIEDOB.

Abstract Hierarchical Text Classification (HTC) is a formidable task which involves classifying textual descriptions into a taxonomic hierarchy. Existing methods, however, have difficulty in adequately modeling the hierarchical label structures, because they tend to focus on employing graph embedding methods to encode the hierarchical structure while disregarding the fact that the HTC labels are rooted in a tree structure. This is significant because, unlike a graph, the tree structure inherently has a directive that ordains information flow from one node to another—a critical factor when applying graph embedding to the HTC task. But in the graph structure, message-passing is undirected, which will lead to the imbalance of message transmission between nodes when applied to HTC. To this end, we propose a unidirectional message-passing multi-label generation model for HTC, referred to as UMP-MG. Instead of viewing HTC as a classification problem as previous methods have done, this novel approach conceptualizes it as a sequence generation task, introducing prior hierarchical information during the decoding process. This further enables the blocking of information flow in one direction to ensure that the graph embedding method is better suited for the HTC task and thus resulted in the enhanced tree structure representation. Results obtained through experimentation on both the public WOS dataset and an E-commerce user intent classification dataset demonstrate that our proposed model can achieve superlative results.

We propose a new photo-realistic, voice driven only (i.e. no linguistic info of the voice input is needed) talking head. The core of the new talking head is a context-dependent, multilayer, Deep Neural Network (DNN), which is discriminatively trained over hundreds of hours, speaker independent speech data. The trained DNN is then used to map acoustic speech input to 9,000 tied “senone” states probabilistically. For each photo-realistic talking head, an HMM-based lips motion synthesizer is trained over the speaker’s audio/visual training data where states are statistically mapped to the corresponding lips images. In test, for given speech input, DNN predicts the likely states in their posterior probabilities and photo-realistic lips animation is then rendered through the DNN predicted state lattice. The DNN trained on English, speaker independent data has also been tested with other language input, e.g. Mandarin, Spanish, etc. to mimic the lips movements cross-lingually. Subjective experiments show that lip motions thus rendered for 15 non-English languages are highly synchronized with the audio input and photo-realistic to human eyes perceptually.