VLDB 2026 Research / reviewers in the wild / expert
Ping Liu 0004
dblp:34/188-4
· DBLP profile ↗
47ranked-venue papers
5as first author
30since 2021 · last 2026
—ORCID · conflict
Domains — the database's venue-derived domains; a paper can count in several
Graphics, computer vision, multimedia, augmented reality and games · 31 · 2 first-author · 20 since 2021Artificial intelligence and machine learning · 29 · 4 first-author · 14 since 2021Databases, data management, data science and information retrieval · 1 · 1 first-author · 1 since 2021Human-computer interaction and ubiquitous computing · 1Applied, interdisciplinary, general and emerging computing · 1
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | SynthIR: The First Workshop on Synthetic Content in Information Retrieval Ecosystems
Ping Liu 0004, Zhedong Zheng, Shane Culpepper, Xin Yu 0002 |
SIGIR | 1 |
| 2026 | RIGI: Rectifying Image-to-3D Generation Inconsistency via Uncertainty-Aware LearningabstractImage-to-3D generation aims to predict a geometrically and perceptually plausible 3D model from a single 2D image. Conventional approaches typically follow a cascaded pipeline: initially generating multi-view projections from the single input image through view synthesis, followed by optimizing 3D geometry and appearance strictly using these projections. However, such deterministic optimization neglects epistemic uncertainty from imperfectly generated data, particularly due to limited observations and inconsistent content. To address this issue, we propose an uncertainty-aware optimization framework that explicitly models and mitigates epistemic uncertainty, leading to more robust and reliable 3D generation. For epistemic uncertainty arising from incomplete viewpoint coverage, we employ a progressive sampling strategy that sinusoidally varies camera elevations and progressively integrates diverse viewpoints into training, enhancing viewpoint coverage and stabilizing optimization. For epistemic uncertainty caused by the deterministic optimization on the noisy and inconsistent generated multi-view frames, we estimate an uncertainty map from the discrepancies between two independently optimized Gaussian models. This map is incorporated into uncertainty-aware regularization, adaptively adjusting loss weights to suppress unreliable supervision. Furthermore, we provide a theoretical analysis of uncertainty-aware optimization by deriving a probabilistic upper bound on the expected generation error, providing insights into its effectiveness. Extensive experiments demonstrate that our method significantly reduces artifacts and inconsistencies, leading to higher-quality 3D generation. More visual results are available at our website https://rigi3d.github.io/. Zhedong Zheng, Wei Xu 0038, Ping Liu 0004 |
IEEE Trans. Image Process. | 4 |
| 2026 | CLIP-SR: Collaborative Linguistic and Image Processing for Super-ResolutionabstractConvolutional Neural Networks (CNNs) have significantly advanced Image Super-Resolution (SR), yet most CNN-based methods rely solely on pixel-based transformations, often leading to artifacts and blurring, particularly under severe downsampling rates (e.g., 8× or 16×). The recently developed text-guided SR approaches leverage textual descriptions to enhance their detail restoration capabilities but frequently struggle with effectively performing alignment, resulting in semantic inconsistencies. To address these challenges, we propose a multi-modal semantic enhancement framework that integrates textual semantics with visual features, effectively mitigating semantic mismatches and detail losses in highly degraded low-resolution (LR) images. Our method enables realistic, high-quality SR to be performed at large upscaling factors, with a maximum scaling ratio of 16×. The framework integrates both text and image inputs using the prompt predictor, the Text-Image Fusion Block (TIFBlock), and the Iterative Refinement Module, leveraging Contrastive Language-Image Pretraining (CLIP) features to guide a progressive enhancement process with fine-grained alignment. This synergy produces high-resolution outputs with sharp textures and strong semantic coherence, even at substantial scaling factors. Extensive comparative experiments and ablation studies validate the effectiveness of our approach. Furthermore, by leveraging textual semantics, our method offers a degree of super-resolution editability, allowing for controlled enhancements while preserving semantic consistency. Bingwen Hu, Heng Liu 0002, Zhedong Zheng, Ping Liu 0004 |
IEEE Trans. Multim. | 4 |
| 2026 | Counterfactual Co-Occurring Learning for Bias Mitigation in Weakly-Supervised Object LocalizationabstractContemporary weakly-supervised object localization (WSOL) methods have primarily focused on addressing the challenge of localizing the most discriminative region while largely overlooking the relatively less explored issue of biased activation—incorrectly spotlighting co-occurring background with the foreground feature. In this paper, we conduct a thorough causal analysis to investigate the origins of biased activation. Based on our analysis, we attribute this phenomenon to the presence of co-occurring background confounders. Building upon this profound insight, we introduce a pioneering paradigm known as Counterfactual Co-occurring Learning (CCL), meticulously engendering counterfactual representations by adeptly disentangling the foreground from the co-occurring background elements. Furthermore, we propose an innovative network architecture known as Counterfactual-CAM. This architecture seamlessly incorporates a perturbation mechanism for counterfactual representations into the vanilla CAM-based model. By training the WSOL model with these perturbed representations, we guide the model to prioritize the consistent foreground content while concurrently reducing the influence of distracting co-occurring backgrounds. To the best of our knowledge, this study represents the initial exploration of this research direction. Our extensive experiments conducted across multiple benchmarks validate the effectiveness of the proposed Counterfactual-CAM in mitigating biased activation. Feifei Shao, Yawei Luo, Lei Chen 0082, Ping Liu 0004, Wei Yang 0034, Yi Yang 0001, Jun Xiao 0001 |
IEEE Trans. Multim. | 4 |
| 2025 | MICAS: Multi-grained In-Context Adaptive Sampling for 3D Point Cloud ProcessingabstractPoint cloud processing (PCP) encompasses tasks like reconstruction, denoising, registration, and segmentation, each often requiring specialized models to address unique task characteristics. While in-context learning (ICL) has shown promise across tasks by using a single model with task-specific demonstration prompts, its application to PCP reveals significant limitations. We identify inter-task and intra-task sensitivity issues in current ICL methods for PCP, which we attribute to inflexible sampling strategies lacking context adaptation at the point and prompt levels. To address these challenges, we propose MICAS, an advanced ICL framework featuring a multi-grained adaptive sampling mechanism tailored for PCP. MICAS introduces two core components: task-adaptive point sampling, which leverages inter-task cues for point-level sampling, and query-specific prompt sampling, which selects optimal prompts per query to mitigate intra-task sensitivity. To our knowledge, this is the first approach to introduce adaptive sampling tailored to the unique requirements of point clouds within an ICL framework. Extensive experiments show that MICAS not only efficiently handles various PCP tasks but also significantly outperforms existing methods. Notably, it achieves a remarkable 4.1% improvement in the part segmentation task and delivers consistent gains across various PCP applications. Feifei Shao, Ping Liu 0004, Yawei Luo, Jun Xiao 0001 |
CVPR | 2 |
| 2025 | Breaking Class Barriers: Efficient Dataset Distillation via Inter-Class Feature CompensatorabstractDataset distillation has emerged as a technique aiming to condense informative features from large, natural datasets into a compact and synthetic form. While recent advancements have refined this technique, its performance is bottlenecked by the prevailing class-specific synthesis paradigm. Under this paradigm, synthetic data is optimized exclusively for a pre-assigned one-hot label, creating an implicit class barrier in feature condensation. This leads to inefficient utilization of the distillation budget and oversight of inter-class feature distributions, which ultimately limits the effectiveness and efficiency, as demonstrated in our analysis.
To overcome these constraints, this paper presents the Inter-class Feature Compensator (INFER), an innovative distillation approach that transcends the class-specific data-label framework widely utilized in current dataset distillation methods. Specifically, INFER leverages a Universal Feature Compensator (UFC) to enhance feature integration across classes, enabling the generation of multiple additional synthetic instances from a single UFC input. This significantly improves the efficiency of the distillation budget.
Moreover, INFER enriches inter-class interactions during the distillation, thereby enhancing the effectiveness and generalizability of the distilled data. By allowing for the linear interpolation of labels similar to those in the original dataset, INFER meticulously optimizes the synthetic data and dramatically reduces the size of soft labels in the synthetic dataset to almost zero, establishing a new benchmark for efficiency and effectiveness in dataset distillation. In practice, INFER demonstrates state-of-the-art performance across benchmark datasets. For instance, in the $\texttt{ipc} = 50$ setting on ImageNet-1k with the same compression level, it outperforms SRe2L by 34.5\% using ResNet18. Codes are available at https://github.com/zhangxin-xd/UFC. Xin Zhang 0092, Jiawei Du 0002, Ping Liu 0004, Joey Tianyi Zhou |
ICLR | 3 |
| 2025 | Grounding Creativity in Physics: A Brief Survey of Physical Priors in AIGCabstractRecent advancements in AI-generated content have significantly improved the realism of 3D and 4D generation. However, most existing methods prioritize appearance consistency while neglecting underlying physical principles, leading to artifacts such as unrealistic deformations, unstable dynamics, and implausible objects interactions. Incorporating physics priors into generative models has become a crucial research direction to enhance structural integrity and motion realism. This survey provides a review of physics-aware generative methods, systematically analyzing how physical constraints are integrated into 3D and 4D generation. First, we examine recent works in incorporating physical priors into static and dynamic 3D generation, categorizing methods based on representation types, including vision-based, NeRF-based, and Gaussian Splatting-based approaches. Second, we explore emerging techniques in 4D generation, focusing on methods that model temporal dynamics with physical simulations. Finally, we conduct a comparative analysis of major methods, highlighting their strengths, limitations, and suitability for different materials and motion dynamics. By presenting an in-depth analysis of physics-grounded AIGC, this survey aims to bridge the gap between generative models and physical realism, providing insights that inspire future research in physically consistent content generation. Siwei Meng, Yawei Luo, Ping Liu 0004 |
IJCAI | 3 |
| 2025 | Kill Two Birds with One Stone: Domain Generalization for Semantic Segmentation via Network Pruning
Yawei Luo, Ping Liu 0004, Yi Yang 0001 |
Int. J. Comput. Vis. | 2 |
| 2025 | DD-RobustBench: An Adversarial Robustness Benchmark for Dataset DistillationabstractDataset distillation techniques have revolutionized the way of utilizing large datasets by compressing them into smaller, yet highly effective subsets that preserve the original datasets' accuracy. However, while these methods have proven effective in reducing data size and training times, the robustness of these distilled datasets against adversarial attacks remains underexplored. This vulnerability poses significant risks, particularly in security-sensitive applications. To address this critical gap, we introduce DD-RobustBench, a novel and comprehensive benchmark specifically designed to evaluate the adversarial robustness of distilled datasets. Our benchmark is the most extensive of its kind and integrates a variety of dataset distillation techniques, including recent advancements such as TESLA, DREAM, SRe2L, and D4M, which have shown promise in enhancing model performance. DD-RobustBench also rigorously tests these datasets against a diverse array of adversarial attack methods to ensure broad applicability. Our evaluations cover a wide spectrum of datasets, including but not limited to, the widely used ImageNet-1K. This allows us to assess the robustness of distilled datasets in scenarios mirroring real-world applications. Furthermore, our detailed quantitative analysis investigates how different components involved in the distillation process, such as data augmentation, downsampling, and clustering, affect dataset robustness. Our findings provide critical insights into which techniques enhance or weaken the resilience of distilled datasets against adversarial threats, offering valuable guidelines for developing more robust distillation methods in the future. Through DD-RobustBench, we aim not only to benchmark but also to push the boundaries of dataset distillation research by highlighting areas for improvement and suggesting pathways for future innovations in creating datasets that are not only compact and efficient but also secure and resilient to adversarial challenges. The implementation details and essential instructions are available on DD-RobustBench. Yifan Wu 0037, Jiawei Du 0002, Ping Liu 0004, Yuewei Lin, Wei Xu 0038, Wenqing Cheng |
IEEE Trans. Image Process. | 3 |
| 2024 | Frequency-Aware Deepfake Detection: Improving Generalizability through Frequency Space Domain LearningabstractThis research addresses the challenge of developing a universal deepfake detector that can effectively identify unseen deepfake images despite limited training data. Existing frequency-based paradigms have relied on frequency-level artifacts introduced during the up-sampling in GAN pipelines to detect forgeries. However, the rapid advancements in synthesis technology have led to specific artifacts for each generation model. Consequently, these detectors have exhibited a lack of proficiency in learning the frequency domain and tend to overfit to the artifacts present in the training data, leading to suboptimal performance on unseen sources. To address this issue, we introduce a novel frequency-aware approach called FreqNet, centered around frequency domain learning, specifically designed to enhance the generalizability of deepfake detectors. Our method forces the detector to continuously focus on high-frequency information, exploiting high-frequency representation of features across spatial and channel dimensions. Additionally, we incorporate a straightforward frequency domain learning module to learn source-agnostic features. It involves convolutional layers applied to both the phase spectrum and amplitude spectrum between the Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (iFFT). Extensive experimentation involving 17 GANs demonstrates the effectiveness of our proposed method, showcasing state-of-the-art performance (+9.8\%) while requiring fewer parameters. The code is available at https://github.com/chuangchuangtan/FreqNet-DeepfakeDetection. Chuangchuang Tan, Yao Zhao 0001, Shikui Wei, Guanghua Gu, Ping Liu 0004, Yunchao Wei |
AAAI | 5 |
| 2024 | Rethinking the Up-Sampling Operations in CNN-Based Generative Network for Generalizable Deepfake DetectionabstractRecently, the proliferation of highly realistic synthetic images, facilitated through a variety of GANs and Diffusions, has significantly heightened the susceptibility to misuse. While the primary focus of deepfake detection has traditionally centered on the design of detection algorithms, an investigative inquiry into the generator architectures has remained conspicuously absent in recent years. This paper contributes to this lacuna by rethinking the architectures of CNN-based generator, thereby establishing a generalized representation of synthetic artifacts. Our findings illuminate that the up-sampling operator can, beyond frequency-based artifacts, produce generalized forgery artifacts. In particular, the local interdependence among image pixels caused by upsampling operators is significantly demon-strated in synthetic images generated by GAN or diffusion. Building upon this observation, we introduce the concept of Neighboring Pixel Relationships(NPR) as a means to capture and characterize the generalized structural artifacts stemming from up-sampling operations. A comprehensive analysis is conducted on an open-world dataset, comprising samples generated by 28 distinct generative models. This analysis culminates in the establishment of a novel state-of-the-art performance, showcasing a remarkable 12.8% im-provement over existing methods. The code is available at https://github.com/chuangchuangtan/NPR-DeepfakeDetection. Chuangchuang Tan, Huan Liu 0001, Yao Zhao 0001, Shikui Wei, Guanghua Gu, Ping Liu 0004, Yunchao Wei |
CVPR | 6 |
| 2024 | Unified Diffusion-Based Rigid and Non-Rigid Editing with Text and Image GuidanceabstractExisting text-to-image editing methods tend to excel either in rigid or non-rigid editing but encounter challenges when combining both, resulting in misaligned outputs with the provided text prompts. In addition, integrating reference images for control remains challenging. To address these issues, we present a versatile image editing framework capable of executing both rigid and non-rigid edits, guided by either textual prompts or reference images. We leverage a dual-path injection scheme to handle diverse editing scenarios and introduce an integrated self-attention mechanism for fusion of appearance and structural information. To mitigate potential visual artifacts, we further employ latent fusion techniques to adjust intermediate latents. Compared to previous work, our approach represents a significant advance in achieving precise and versatile image editing. Comprehensive experiments validate the efficacy of our method, showcasing competitive or superior results in text-based editing and appearance transfer tasks, encompassing both rigid and non-rigid settings. Ping Liu 0004, Wei Xu 0038 |
ICME | 2 |
| 2024 | VehicleGAN: Pair-flexible Pose Guided Image Synthesis for Vehicle Re-identificationabstractVehicle Re-identification (Re-ID) has been broadly studied in the last decade; however, the different camera view angles leading to confused discrimination in the feature subspace for the vehicles of various poses, is still challenging for the Vehicle Re-ID models in the real world. To promote the Vehicle Re-ID models, this paper proposes to synthesize a large number of vehicle images in the target pose, whose idea is to project the vehicles of diverse poses into the unified target pose so as to enhance feature discrimination. Considering that the paired data of the same vehicles in different traffic surveillance cameras might be not available in the real world, we propose the first Pair-flexible Pose Guided Image Synthesis method for Vehicle Re-ID, named as VehicleGAN in this paper, which works for both supervised and unsupervised settings without the knowledge of geometric 3D models. Because of the feature distribution difference between real and synthetic data, simply training a traditional metric learning based Re-ID model with data-level fusion (i.e., data augmentation) is not satisfactory, therefore we propose a new Joint Metric Learning (JML) via effective feature-level fusion from both real and synthetic data. Intensive experimental results on the public VeRi-776 and VehicleID datasets prove the accuracy and effectiveness of our proposed VehicleGAN and JML. Ping Liu 0004, Lan Fu, Jianwu Fang, Zhigang Xu 0001, Hongkai Yu |
IV | 2 |
| 2024 | Text-Guided Eyeglasses Manipulation With Spatial ConstraintsabstractVirtual try-on of eyeglasses involves placing eyeglasses of different shapes and styles onto a face image without physically trying them on. While existing methods have shown impressive results, the variety of eyeglasses styles is limited and the interactions are not always intuitive or efficient. To address these limitations, we propose GlassesCLIP, a text-guided eyeglasses manipulation method with spatial constraints, which allows for control of the eyeglasses shape and style based on a binary mask and text, respectively. Specifically, we introduce a mask encoder to extract mask conditions and a modulation module that enables simultaneous injection of text and mask conditions. This design allows for fine-grained control of the eyeglasses' appearance based on both textual descriptions and spatial constraints. Our approach includes a disentangled mapper and a decoupling strategy that preserves irrelevant areas, resulting in better local editing. We employ a two-stage training scheme to handle the different convergence speeds of the various modality conditions, successfully controlling both the shape and style of eyeglasses. Extensive comparison experiments and ablation analyses demonstrate the effectiveness of our approach in achieving diverse eyeglasses styles while preserving irrelevant areas. Ping Liu 0004, Jingen Liu, Wei Xu 0038 |
IEEE Trans. Multim. | 2 |
| 2023 | Generative Gradient Inversion via Over-Parameterized Networks in Federated LearningabstractFederated learning has gained recognitions as a secure approach for safeguarding local private data in collaborative learning. But the advent of gradient inversion research has posed significant challenges to this premise by enabling a third-party to recover groundtruth images via gradients. While prior research has predominantly focused on low-resolution images and small batch sizes, this study highlights the feasibility of reconstructing complex images with high resolutions and large batch sizes. The success of the proposed method is contingent on constructing an over-parameterized convolutional network, so that images are generated before fitting to the gradient matching requirement. Practical experiments demonstrate that the proposed algorithm achieves high-fidelity image recovery, surpassing state-of-the-art competitors that commonly fail in more intricate scenarios. Consequently, our study shows that local participants in a federated learning system are vulnerable to potential data leakage issues. Source code is available at https://github.com/czhang024/CI-Net. Chi Zhang 0123, Xiaoman Zhang, Ekanut Sotthiwat, Yanyu Xu 0001, Ping Liu 0004, Liangli Zhen, Yong Liu 0026 |
ICCV | 5 |
| 2023 | Unsupervised Domain Adaptive Person Re-Identification with Adaptive Structure LearningabstractUnsupervised domain adaptive person re-identification has garnered considerable attention due to its practical significance. Previous research has focused on utilizing the teacher-student framework within the clustering and fine-tuning paradigm to reduce the domain gap between different person re-identification datasets. Building upon these recent advancements, we propose a novel approach to further explore the structural information of the teacher and student networks from multiple perspectives, including adaptive sample updating, global feature arrangement, and local discrepancy learning. By integrating these three components, we introduce the Adaptive Structure Learning Framework (ASL) for unsupervised domain adaptive person re-identification. Compared to the baseline method, our approach achieves a significant improvement of 7.3% in mean Average Precision (mAP) on the Market2MSMT task. Furthermore, our experimental results across three benchmark datasets provide further evidence of the effectiveness of our proposed method. Ping Liu 0004, Xiyuan Yang, Pan Zhou 0001, Yawei Luo, Jingen Liu |
ICIP | 2 |
| 2023 | Meta Knowledge Condensation for Federated Learning
Ping Liu 0004, Xin Yu 0002, Joey Tianyi Zhou |
ICLR | 1 |
| 2023 | CLE Diffusion: Controllable Light Enhancement Diffusion ModelabstractLow light enhancement has gained increasing importance with the rapid development of visual creation and editing. However, most existing enhancement algorithms are designed to homogeneously increase the brightness of images to a pre-defined extent, limiting the user experience. To address this issue, we propose Controllable Light Enhancement Diffusion Model, dubbed CLE Diffusion, a novel diffusion framework to provide users with rich controllability.Built with a conditional diffusion model, we introduce an illumination embedding to let users control their desired brightness level. Additionally, we incorporate the Segment-Anything Model (SAM) to enable user-friendly region controllability, where users can click on objects to specify the regions they wish to enhance. Extensive experiments demonstrate that CLE Diffusion achieves competitive performance regarding quantitative metrics, qualitative results, and versatile controllability. Project page: https://yuyangyin.github.io/CLEDiffusion Yuyang Yin, Dejia Xu, Chuangchuang Tan, Ping Liu 0004, Yao Zhao 0001, Yunchao Wei |
ACM Multimedia | 4 |
| 2023 | Filter Pruning by Switching to Neighboring CNNs With Good AttributesabstractFilter pruning is effective to reduce the computational costs of neural networks. Existing methods show that updating the previous pruned filter would enable large model capacity and achieve better performance. However, during the iterative pruning process, even if the network weights are updated to new values, the pruning criterion remains the same. In addition, when evaluating the filter importance, only the magnitude information of the filters is considered. However, in neural networks, filters do not work individually, but they would affect other filters. As a result, the magnitude information of each filter, which merely reflects the information of an individual filter itself, is not enough to judge the filter importance. To solve the above problems, we propose meta-attribute-based filter pruning (MFP). First, to expand the existing magnitude information-based pruning criteria, we introduce a new set of criteria to consider the geometric distance of filters. Additionally, to explicitly assess the current state of the network, we adaptively select the most suitable criteria for pruning via a meta-attribute, a property of the neural network at the current state. Experiments on two image classification benchmarks validate our method. For ResNet-50 on ILSVRC-2012, we could reduce more than 50% FLOPs with only 0.44% top-5 accuracy loss. Yang He 0002, Ping Liu 0004, Linchao Zhu, Yi Yang 0001 |
IEEE Trans. Neural Networks Learn. Syst. | 2 |
| 2022 | Active Learning for Point Cloud Semantic Segmentation via Spatial-Structural Diversity ReasoningabstractThe expensive annotation cost is notoriously known as the main constraint for the development of the point cloud semantic segmentation technique. Active learning methods endeavor to reduce such cost by selecting and labeling only a subset of the point clouds, yet previous attempts ignore the spatial-structural diversity of the selected samples, inducing the model to select clustered candidates with similar shapes in a local area while missing other representative ones in the global environment. In this paper, we propose a new 3D region-based active learning method to tackle this problem. Dubbed SSDR-AL, our method groups the original point clouds into superpoints and incrementally selects the most informative and representative ones for label acquisition. We achieve the selection mechanism via a graph reasoning network that considers both the spatial and structural diversities of superpoints. To deploy SSDR-AL in a more practical scenario, we design a noise-aware iterative labeling strategy to confront the "noisy annotation'' problem introduced by the previous "dominant labeling'' strategy in superpoints. Extensive experiments on two point cloud benchmarks demonstrate the effectiveness of SSDR-AL in the semantic segmentation task. Particularly, SSDR-AL significantly outperforms the baseline method and reduces the annotation cost by up to $63.0%$ and $24.0%$ when achieving $90%$ performance of fully supervised learning, respectively. Code is available at https://github.com/shaofeifei11/SSDR-AL. Feifei Shao, Yawei Luo, Ping Liu 0004, Yi Yang 0001, Yulei Lu, Jun Xiao 0001 |
ACM Multimedia | 3 |
| 2022 | Adversarial Semantic Hallucination for Domain Generalized Semantic SegmentationabstractConvolutional neural networks typically perform poorly when the test (target domain) and training (source domain) data have significantly different distributions. While this problem can be mitigated by using the target domain data to align the source and target domain feature representations, the target domain data may be unavailable due to privacy concerns. Consequently, there is a need for methods that generalize well despite restricted access to target domain data during training. In this work, we propose an adversarial semantic hallucination approach (ASH), which combines a class-conditioned hallucination module and a semantic segmentation module. Since the segmentation performance varies across different classes, we design a semantic-conditioned style hallucination module to generate affine transformation parameters from semantic information in the segmentation probability maps of the source domain image. Unlike previous adaptation approaches, which treat all classes equally, ASH considers the class-wise differences. The segmentation module and the hallucination module compete adversarially, with the hallucination module generating increasingly "difficult" stylized images to challenge the segmentation module. In response, the segmentation module improves as it is trained with generated samples at an appropriate class-wise difficulty level. Our results on the Cityscapes and Mapillary benchmark datasets show that our method is competitive with state of the art work. Code is made available at https://github.com/gabriel-tjio/ASH. Gabriel Tjio, Ping Liu 0004, Joey Tianyi Zhou, Rick Siow Mong Goh |
WACV | 2 |
| 2022 | Category-Level Adversarial Adaptation for Semantic Segmentation Using Purified FeaturesabstractWe target the problem named unsupervised domain adaptive semantic segmentation. A key in this campaign consists in reducing the domain shift, so that a classifier based on labeled data from one domain can generalize well to other domains. With the advancement of adversarial learning method, recent works prefer the strategy of aligning the marginal distribution in the feature spaces for minimizing the domain discrepancy. However, based on the observance in experiments, only focusing on aligning global marginal distribution but ignoring the local joint distribution alignment fails to be the optimal choice. Other than that, the noisy factors existing in the feature spaces, which are not relevant to the target task, entangle with the domain invariant factors improperly and make the domain distribution alignment more difficult. To address those problems, we introduce two new modules, Significance-aware Information Bottleneck (SIB) and Category-level alignment (CLA), to construct a purified embedding-based category-level adversarial network. As the name suggests, our designed network, CLAN, can not only disentangle the noisy factors and suppress their influences for target tasks but also utilize those purified features to conduct a more delicate level domain calibration, i.e., global marginal distribution and local joint distribution alignment simultaneously. In three domain adaptation tasks, i.e., GTA5 → Cityscapes, SYNTHIA → Cityscapes and Cross Season, we validate that our proposed method matches the state of the art in segmentation accuracy. Yawei Luo, Ping Liu 0004, Liang Zheng 0001, Junqing Yu, Yi Yang 0001 |
IEEE Trans. Pattern Anal. Mach. Intell. | 2 |
| 2022 | Unsupervised Visual Representation Learning via Dual-Level Progressive Similar Instance SelectionabstractThe superiority of deeply learned representations relies on large-scale labeled datasets. However, annotating data are usually expensive or even infeasible in some scenarios. To address this problem, we propose an unsupervised method to leverage instance discrimination and similarity for deep visual representation learning. The method is based on an observation that convolutional neural networks (CNNs) can learn a meaningful visual representation with instancewise classification, in which each instance is treated as an individual class. By this instancewise discriminative learning, instances can reasonably distribute in the representation space, which reveals their similarities. In order to further improve visual representations, we propose a dual-level progressive similar instance selection (DPSIS) method to build a bridge from instance to class by selecting similar instances (neighbors) for each instance (anchor) and treating the anchor and its neighbors as the same class. To be specific, DPSIS adaptively selects two levels of neighbors, that is: 1) an "absolutely similar level" and 2) a "relatively similar level." Instances in the absolutely similar level are used as hard labels, while instances in the relatively similar level are used as soft labels. Moreover, during training, DPSIS is able to progressively select more neighbors without human supervision. At the beginning of training, because CNNs are weak, most instances are distributed relatively randomly in the representation space and only a few easy-to-recognize instances are selected as neighbors. As CNN models become stronger, the semantic meaning of each instance grows clearer. Those instances originally distributed in a relatively random manner gradually move to meaningful positions. This consequently facilitates CNN training since the number of reliable samples increases. Experiments on seven benchmarks, including three small-scale and two large-scale coarse-grained image classification datasets, and two fine-grained categorization datasets, demonstrate the effectiveness of our DPSIS. Our codes have been released at https://github.com/hehefan/DPSIS. Hehe Fan, Ping Liu 0004, Mingliang Xu 0001, Yi Yang 0001 |
IEEE Trans. Cybern. | 2 |
| 2022 | Point Adversarial Self-Mining: A Simple Method for Facial Expression RecognitionabstractIn this article, we propose a simple yet effective approach, called point adversarial self mining (PASM), to improve the recognition accuracy in facial expression recognition (FER). Unlike previous works focusing on designing specific architectures or loss functions to solve this problem, PASM boosts the network capability by simulating human learning processes: providing updated learning materials and guidance from more capable teachers. Specifically, to generate new learning materials, PASM leverages a point adversarial attack method and a trained teacher network to locate the most informative position related to the target task, generating harder learning samples to refine the network. The searched position is highly adaptive since it considers both the statistical information of each sample and the teacher network capability. Other than being provided new learning materials, the student network also receives guidance from the teacher network. After the student network finishes training, the student network changes its role and acts as a teacher, generating new learning materials and providing stronger guidance to train a better student network. The adaptive learning materials generation and teacher/student update can be conducted more than one time, improving the network capability iteratively. Extensive experimental results validate the efficacy of our method over the existing state of the arts for FER. Ping Liu 0004, Yuewei Lin, Zibo Meng, Weihong Deng, Joey Tianyi Zhou, Yi Yang 0001 |
IEEE Trans. Cybern. | 1 |
| 2022 | Pro-UIGAN: Progressive Face Hallucination From Occluded ThumbnailsabstractIn this paper, we study the task of hallucinating an authentic high-resolution (HR) face from an occluded thumbnail. We propose a multi-stage Progressive Upsampling and Inpainting Generative Adversarial Network, dubbed Pro-UIGAN, which exploits facial geometry priors to replenish and upsample ( 8× ) the occluded and tiny faces ( 16×16 pixels). Pro-UIGAN iteratively (1) estimates facial geometry priors for low-resolution (LR) faces and (2) acquires non-occluded HR face images under the guidance of the estimated priors. Our multi-stage hallucination network upsamples and inpaints occluded LR faces via a coarse-to-fine fashion, significantly reducing undesirable artifacts and blurriness. Specifically, we design a novel cross-modal attention module for facial priors estimation, in which an input face and its landmark features are formulated as queries and keys, respectively. Such a design encourages joint feature learning across the input facial and landmark features, and deep feature correspondences will be discovered by attention. Thus, facial appearance features and facial geometry priors are learned in a mutually beneficial manner. Extensive experiments show that our Pro-UIGAN attains visually pleasing completed HR faces, thus facilitating downstream tasks, i.e., face alignment, face parsing, face recognition as well as expression classification. Yang Zhang 0067, Xin Yu 0002, Xiaobo Lu, Ping Liu 0004 |
IEEE Trans. Image Process. | 4 |
| 2022 | SPG-VTON: Semantic Prediction Guidance for Multi-Pose Virtual Try-onabstractImage-based virtual try-on is challenging in fitting a target in-shop clothes onto a reference person under diverse human poses. Previous works focus on preserving clothing details (e.g.,texture, logos, patterns) when transferring desired clothes onto a target person under a fixed pose. However, the performances of existing methods significantly dropped when extending existing methods to multi-pose virtual try-on. In this paper, we propose an end-to-end Semantic Prediction Guidance multi-pose Virtual Try-On Network (SPG-VTON), which can fit the desired clothing into a reference person under arbitrary poses. Specifically, SPG-VTON is composed of three sub-modules. First, a Semantic Prediction Module (SPM) generates the desired semantic map. The predicted semantic map provides more abundant guidance to locate the desired clothing region and produce a coarse try-on image. Second, a Clothes Warping Module (CWM) warps in-shop clothes to the desired shape according to the predicted semantic map and the desired pose. Specifically, we introduce a conductible cycle consistency loss to alleviate the misalignment in the clothing warping process. Third, a Try-on Synthesis Module (TSM) combines the coarse result and the warped clothes to generate the final virtual try-on image, preserving details of the desired clothes and under the desired pose. In addition, we introduce a face identity loss to refine the facial appearance and maintain the identity of the final virtual try-on result at the same time. We evaluate the proposed method on the most massive multi-pose dataset (MPV) and the DeepFashion dataset. The qualitative and quantitative experiments show that SPG-VTON is superior to the state-of-the-art methods and is robust to data noise, including background and accessory changes,i.e., hats and handbags, showing good scalability to the real-world scenario. Bingwen Hu, Ping Liu 0004, Zhedong Zheng, Mingwu Ren |
IEEE Trans. Multim. | 2 |
| 2021 | Hierarchical Temporal Modeling With Mutual Distance Matching for Video Based Person Re-IdentificationabstractComparing to image-based person re-identification (re-ID) problems, video-based person re-ID can take advantage of more cues from appearance and temporal information, and therefore receives widespread attention recently. However, due to the different pose, occlusion, misalignment and multi-granularity in video sequences, those consequent inter-sequence variations and intra-sequence variations, inevitably makes the feature learning and matching in videos more difficult. Under this circumstance, it is necessary to design an effective discriminative representation learning mechanism, as well as a matching solution, to tackle these variations in video-based person re-ID. To this end, this paper introduces a multi-granularity temporal convolution network and a mutual distance matching measurement, aiming at alleviating the intra-sequence variation and the inter-sequence variation, respectively. Particularly, in the feature learning stage, we model different temporal granularities by hierarchically stacking temporal convolution blocks with different dilation factors. In the feature matching stage, we propose a clip-level probe-gallery mutual distance measurement and consider the most convincing clip pairs by top-k selection. We validate that our proposed method can achieve state-of-the-art results on three video-based person re-ID benchmarks, more than that, we conduct extensive ablation study to demonstrate conciseness and effectiveness of our method in video re-ID tasks. Peike Li, Pingbo Pan, Ping Liu 0004, Mingliang Xu 0001, Yi Yang 0001 |
IEEE Trans. Circuits Syst. Video Technol. | 3 |
| 2021 | Unsupervised Eyeglasses Removal in the WildabstractEyeglasses removal is challenging in removing different kinds of eyeglasses, e.g., rimless glasses, full-rim glasses, and sunglasses, and recovering appropriate eyes. Due to the significant visual variants, the conventional methods lack scalability. Most existing works focus on the frontal face images in the controlled environment, such as the laboratory, and need to design specific systems for different eyeglass types. To address the limitation, we propose a unified eyeglass removal model called the eyeglasses removal generative adversarial network (ERGAN), which could handle different types of glasses in the wild. The proposed method does not depend on the dense annotation of eyeglasses location but benefits from the large-scale face images with weak annotations. Specifically, we study the two relevant tasks simultaneously, that is, removing eyeglasses and wearing eyeglasses. Given two face images with and without eyeglasses, the proposed model learns to swap the eye area in two faces. The generation mechanism focuses on the eye area and invades the difficulty of generating a new face. In the experiment, we show the proposed method achieves a competitive removal quality in terms of realism and diversity. Furthermore, we evaluate ERGAN on several subsequent tasks, such as face verification and facial expression recognition. The experiment shows that our method could serve as a preprocessing method for these tasks. Bingwen Hu, Zhedong Zheng, Ping Liu 0004, Wankou Yang, Mingwu Ren |
IEEE Trans. Cybern. | 3 |
| 2021 | Discriminative Feature Learning for Thorax Disease Classification in Chest X-ray ImagesabstractThis paper focuses on the thorax disease classification problem in chest X-ray (CXR) images. Different from the generic image classification task, a robust and stable CXR image analysis system should consider the unique characteristics of CXR images. Particularly, it should be able to: 1) automatically focus on the disease-critical regions, which usually are of small sizes; 2) adaptively capture the intrinsic relationships among different disease features and utilize them to boost the multi-label disease recognition rates jointly. In this paper, we propose to learn discriminative features with a two-branch architecture, named ConsultNet, to achieve those two purposes simultaneously. ConsultNet consists of two components. First, an information bottleneck constrained feature selector extracts critical disease-specific features according to the feature importance. Second, a spatial-and-channel encoding based feature integrator enhances the latent semantic dependencies in the feature space. ConsultNet fuses these discriminative features to improve the performance of thorax disease classification in CXRs. Experiments conducted on the ChestX-ray14 and CheXpert dataset demonstrate the effectiveness of the proposed method. Qingji Guan, Yawei Luo, Ping Liu 0004, Mingliang Xu 0001, Yi Yang 0001 |
IEEE Trans. Image Process. | 4 |
| 2021 | Face Hallucination With Finishing TouchesabstractObtaining a high-quality frontal face image from a low-resolution (LR) non-frontal face image is primarily important for many facial analysis applications. However, mainstreams either focus on super-resolving near-frontal LR faces or frontalizing non-frontal high-resolution (HR) faces. It is desirable to perform both tasks seamlessly for daily-life unconstrained face images. In this paper, we present a novel Vivid Face Hallucination Generative Adversarial Network (VividGAN) for simultaneously super-resolving and frontalizing tiny non-frontal face images. VividGAN consists of coarse-level and fine-level Face Hallucination Networks (FHnet) and two discriminators, i.e., Coarse-D and Fine-D. The coarse-level FHnet generates a frontal coarse HR face and then the fine-level FHnet makes use of the facial component appearance prior, i.e., fine-grained facial components, to attain a frontal HR face image with authentic details. In the fine-level FHnet, we also design a facial component-aware module that adopts the facial geometry guidance as clues to accurately align and merge the frontal coarse HR face and prior information. Meanwhile, two-level discriminators are designed to capture both the global outline of a face image as well as detailed facial characteristics. The Coarse-D enforces the coarsely hallucinated faces to be upright and complete while the Fine-D focuses on the fine hallucinated ones for sharper details. Extensive experiments demonstrate that our VividGAN achieves photo-realistic frontal HR faces, reaching superior performance in downstream tasks, i.e., face recognition and expression classification, compared with other state-of-the-art methods. Yang Zhang 0067, Ivor W. Tsang, Jun Li 0010, Ping Liu 0004, Xiaobo Lu, Xin Yu 0002 |
IEEE Trans. Image Process. | 4 |
| 2020 | Adversarial Localized Energy Network for Structured PredictionabstractThis paper focuses on energy model based structured output prediction. Though inheriting the benefits from energy-based models to handle the sophisticated cases, previous deep energy-based methods suffered from the substantial computation cost introduced by the enormous amounts of gradient steps in the inference process. To boost the efficiency and accuracy of the energy-based models on structured output prediction, we propose a novel method analogous to the adversarial learning framework. Specifically, in our proposed framework, the generator consists of an inference network while the discriminator is comprised of an energy network. The two sub-modules, i.e., the inference network and the energy network, can benefit each other mutually during the whole computation process. On the one hand, our modified inference network can boost the efficiency by predicting good initializations and reducing the searching space for the inference process; On the other hand, inheriting the benefits of the energy network, the energy module in our network can evaluate the quality of the generated output from the inference network and correspondingly provides a resourceful guide to the training of the inference network. In the ideal case, the adversarial learning strategy makes sure the two sub-modules can achieve an equilibrium state after steps. We conduct extensive experiments to verify the effectiveness and efficiency of our proposed method. Pingbo Pan, Ping Liu 0004, Yan Yan 0006, Tianbao Yang, Yi Yang 0001 |
AAAI | 2 |
| 2020 | Learning Filter Pruning Criteria for Deep Convolutional Neural Networks AccelerationabstractFilter pruning has been widely applied to neural network compression and acceleration. Existing methods usually utilize pre-defined pruning criteria, such as Lp-norm, to prune unimportant filters. There are two major limitations to these methods. First, existing methods fail to consider the variety of filter distribution across layers. To extract features of the coarse level to the fine level, the filters of different layers have various distributions. Therefore, it is not suitable to utilize the same pruning criteria to different functional layers. Second, prevailing layer-by-layer pruning methods process each layer independently and sequentially, failing to consider that all the layers in the network collaboratively make the final prediction. In this paper, we propose Learning Filter Pruning Criteria (LFPC) to solve the above problems. Specifically, we develop a differentiable pruning criteria sampler. This sampler is learnable and optimized by the validation loss of the pruned network obtained from the sampled criteria. In this way, we could adaptively select the appropriate pruning criteria for different functional layers. Besides, when evaluating the sampled criteria, LFPC comprehensively consider the contribution of all the layers at the same time. Experiments validate our approach on three image classification benchmarks. Notably, on ILSVRC-2012, our LFPC reduces more than 60% FLOPs on ResNet-50 with only 0.83% top-5 accuracy loss. Yang He 0002, Yuhang Ding, Ping Liu 0004, Linchao Zhu, Hanwang Zhang, Yi Yang 0001 |
CVPR | 3 |
| 2020 | Adversarial Style Mining for One-Shot Unsupervised Domain AdaptationabstractWe aim at the problem named One-Shot Unsupervised Domain Adaptation. Unlike traditional Unsupervised Domain Adaptation, it assumes that only one unlabeled target sample can be available when learning to adapt. This setting is realistic but more challenging, in which conventional adaptation approaches are prone to failure due to the scarce of unlabeled target data. To this end, we propose a novel Adversarial Style Mining approach, which combines the style transfer module and task-specific module into an adversarial manner. Specifically, the style transfer module iteratively searches for harder stylized images around the one-shot target sample according to the current learning state, leading the task model to explore the potential styles that are difficult to solve in the almost unseen target domain, thus boosting the adaptation performance in a data-scarce scenario. The adversarial learning framework makes the style transfer module and task-specific module benefit each other during the competition. Extensive experiments on both cross-domain classification and segmentation benchmarks verify that ASM achieves state-of-the-art adaptation performance under the challenging one-shot setting. Yawei Luo, Ping Liu 0004, Junqing Yu, Yi Yang 0001 |
NeurIPS | 2 |
| 2020 | Every node counts: Self-ensembling graph convolutional networks for semi-supervised learning
Yawei Luo, Rongrong Ji, Junqing Yu, Ping Liu 0004, Yi Yang 0001 |
Pattern Recognit. | 5 |
| 2019 | Filter Pruning via Geometric Median for Deep Convolutional Neural Networks AccelerationabstractPrevious works utilized “smaller-norm-less-important” criterion to prune filters with smaller norm values in a convolutional neural network. In this paper, we analyze this norm-based criterion and point out that its effectiveness depends on two requirements that are not always met: (1) the norm deviation of the filters should be large; (2) the minimum norm of the filters should be small. To solve this problem, we propose a novel filter pruning method, namely Filter Pruning via Geometric Median (FPGM), to compress the model regardless of those two requirements. Unlike previous methods, FPGM compresses CNN models by pruning filters with redundancy, rather than those with“relatively less” importance. When applied to two image classification benchmarks, our method validates its usefulness and strengths. Notably, on CIFAR-10, FPGM reduces more than 52% FLOPs on ResNet-110 with even 2.69% relative accuracy improvement. Moreover, on ILSVRC-2012, FPGM reduces more than 42% FLOPs on ResNet-101 without top-5 accuracy drop, which has advanced the state-of-the-art. Code is publicly available on GitHub: https://github.com/he-y/filter-pruning-geometric-median Yang He 0002, Ping Liu 0004, Zhilan Hu, Yi Yang 0001 |
CVPR | 2 |
| 2019 | Entangled Transformer for Image CaptioningabstractIn image captioning, the typical attention mechanisms are arduous to identify the equivalent visual signals especially when predicting highly abstract words. This phenomenon is known as the semantic gap between vision and language. This problem can be overcome by providing semantic attributes that are homologous to language. Thanks to the inherent recurrent nature and gated operating mechanism, Recurrent Neural Network (RNN) and its variants are the dominating architectures in image captioning. However, when designing elaborate attention mechanisms to integrate visual inputs and semantic attributes, RNN-like variants become unflexible due to their complexities. In this paper, we investigate a Transformer-based sequence modeling framework, built only with attention layers and feedforward layers. To bridge the semantic gap, we introduce EnTangled Attention (ETA) that enables the Transformer to exploit semantic and visual information simultaneously. Furthermore, Gated Bilateral Controller (GBC) is proposed to guide the interactions between the multimodal information. We name our model as ETA-Transformer. Remarkably, ETA-Transformer achieves state-of-the-art performance on the MSCOCO image captioning dataset. The ablation studies validate the improvements of our proposed modules. Linchao Zhu, Ping Liu 0004, Yi Yang 0001 |
ICCV | 3 |
| 2019 | Significance-Aware Information Bottleneck for Domain Adaptive Semantic SegmentationabstractFor unsupervised domain adaptation problems, the strategy of aligning the two domains in latent feature space through adversarial learning has achieved much progress in image classification, but usually fails in semantic segmentation tasks in which the latent representations are overcomplex. In this work, we equip the adversarial network with a “significance-aware information bottleneck (SIB)”, to address the above problem. The new network structure, called SIBAN, enables a significance-aware feature purification before the adversarial adaptation, which eases the feature alignment and stabilizes the adversarial training course. In two domain adaptation tasks, i.e., GTA5 → Cityscapes and SYNTHIA → Cityscapes, we validate that the proposed method can yield leading results compared with other feature-space alternatives. Moreover, SIBAN can even match the state-of-the-art output-space methods in segmentation accuracy, while the latter are often considered to be better choices for domain adaptive segmentation task. Yawei Luo, Ping Liu 0004, Junqing Yu, Yi Yang 0001 |
ICCV | 2 |
| 2019 | Pose-Guided Feature Alignment for Occluded Person Re-IdentificationabstractPersons are often occluded by various obstacles in person retrieval scenarios. Previous person re-identification (re-id) methods, either overlook this issue or resolve it based on an extreme assumption. To alleviate the occlusion problem, we propose to detect the occluded regions, and explicitly exclude those regions during feature generation and matching. In this paper, we introduce a novel method named Pose-Guided Feature Alignment (PGFA), exploiting pose landmarks to disentangle the useful information from the occlusion noise. During the feature constructing stage, our method utilizes human landmarks to generate attention maps. The generated attention maps indicate if a specific body part is occluded and guide our model to attend to the non-occluded regions. During matching, we explicitly partition the global feature into parts and use the pose landmarks to indicate which partial features belonging to the target person. Only the visible regions are utilized for the retrieval. Besides, we construct a large-scale dataset for the Occluded Person Re-ID problem, namely Occluded-DukeMTMC, which is by far the largest dataset for the Occlusion Person Re-ID. Extensive experiments are conducted on our constructed occluded re-id dataset, two partial re-id datasets, and two commonly used holistic re-id datasets. Our method largely outperforms existing person re-id methods on three occlusion datasets, while remains top performance on two holistic datasets. Jiaxu Miao, Yu Wu 0011, Ping Liu 0004, Yuhang Ding, Yi Yang 0001 |
ICCV | 3 |
| 2019 | Very Long Natural Scenery Image Prediction by OutpaintingabstractComparing to image inpainting, image outpainting receives less attention due to two challenges in it. The first challenge is how to keep the spatial and content consistency between generated images and original input. The second challenge is how to maintain high quality in generated results, especially for multi-step generations in which generated regions are spatially far away from the initial input. To solve the two problems, we devise some innovative modules, named Skip Horizontal Connection and Recurrent Content Transfer, and integrate them into our designed encoder-decoder structure. By this design, our network can generate highly realistic outpainting prediction effectively and efficiently. Other than that, our method can generate new images with very long sizes while keeping the same style and semantic content as the given input. To test the effectiveness of the proposed architecture, we collect a new scenery dataset with diverse, complicated natural scenes. The experimental results on this dataset have demonstrated the efficacy of our proposed network. Zongxin Yang, Jian Dong 0011, Ping Liu 0004, Yi Yang 0001, Shuicheng Yan |
ICCV | 3 |
| 2019 | Improving Speech Related Facial Action Unit Recognition by Audiovisual Information FusionabstractIt is challenging to recognize facial action unit (AU) from spontaneous facial displays, especially when they are accompanied by speech. The major reason is that the information is extracted from a single source, i.e., the visual channel, in the current practice. However, facial activity is highly correlated with voice in natural human communications. Instead of solely improving visual observations, this paper presents a novel audiovisual fusion framework, which makes the best use of visual and acoustic cues in recognizing speech-related facial AUs. In particular, a dynamic Bayesian network is employed to explicitly model the semantic and dynamic physiological relationships between AUs and phonemes as well as measurement uncertainty. Experiments on a pilot audiovisual AU-coded database have demonstrated that the proposed framework significantly outperforms the state-of-the-art visual-based methods in terms of recognizing speech-related AUs, especially for those AUs whose visual observations are impaired during speech, and more importantly is also superior to audio-based methods and feature-level fusion methods, which employ low-level audio features, by explicitly modeling and exploiting physiological relationships between AUs and phonemes. Zibo Meng, Shizhong Han, Ping Liu 0004 |
IEEE Trans. Cybern. | 3 |
| 2017 | Identity-Aware Convolutional Neural Network for Facial Expression RecognitionabstractFacial expression recognition suffers under realworldconditions, especially on unseen subjects due to highinter-subject variations. To alleviate variations introduced bypersonal attributes and achieve better facial expression recognitionperformance, a novel identity-aware convolutional neuralnetwork (IACNN) is proposed. In particular, a CNN with a newarchitecture is employed as individual streams of a bi-streamidentity-aware network. An expression-sensitive contrastive lossis developed to measure the expression similarity to ensure thefeatures learned by the network are invariant to expressionvariations. More importantly, an identity-sensitive contrastiveloss is proposed to learn identity-related information from identitylabels to achieve identity-invariant expression recognition.Extensive experiments on three public databases including aspontaneous facial expression database have shown that theproposed IACNN achieves promising results in real world. Zibo Meng, Ping Liu 0004, Jie Cai 0001, Shizhong Han |
FG | 2 |
| 2014 | Facial Expression Recognition via a Boosted Deep Belief NetworkabstractA training process for facial expression recognition is usually performed sequentially in three individual stages: feature learning, feature selection, and classifier construction. Extensive empirical studies are needed to search for an optimal combination of feature representation, feature set, and classifier to achieve good recognition performance. This paper presents a novel Boosted Deep Belief Network (BDBN) for performing the three training stages iteratively in a unified loopy framework. Through the proposed BDBN framework, a set of features, which is effective to characterize expression-related facial appearance/shape changes, can be learned and selected to form a boosted strong classifier in a statistical way. As learning continues, the strong classifier is improved iteratively and more importantly, the discriminative capabilities of selected features are strengthened as well according to their relative importance to the strong classifier via a joint fine-tune process in the BDBN framework. Extensive experiments on two public databases showed that the BDBN framework yielded dramatic improvements in facial expression analysis. Ping Liu 0004, Shizhong Han, Zibo Meng |
CVPR | 1 |
| 2014 | Feature Disentangling Machine - A Novel Approach of Feature Selection and Disentangling in Facial Expression Analysis
Ping Liu 0004, Joey Tianyi Zhou, Ivor W. Tsang, Zibo Meng, Shizhong Han |
ECCV (4) | 1 |
| 2014 | Facial grid transformation: A novel face registration approach for improving facial action unit recognitionabstractFace registration is a major and critical step for face analysis. Existing facial activity recognition systems often employ coarse face alignment based on a few fiducial points such as eyes and extract features from equal-sized grid. Such extracted features are susceptible to variations in face pose, facial deformation, and person-specific geometry. In this work, we propose a novel face registration method named facial grid transformation to improve feature extraction for recognizing facial Action Units (AUs). Based on the transformed grid, novel grid edge features are developed to capture local facial motions related to AUs. Extensive experiments on two well-known AU-coded databases have demonstrated that the proposed method yields significant improvements over the methods based on equal-sized grid on both posed and more importantly, spontaneous facial displays. Furthermore, the proposed method also outperforms the state-of-the-art methods using either coarse alignment or mesh-based face registration. Shizhong Han, Zibo Meng, Ping Liu 0004 |
ICIP | 3 |
| 2013 | Supervised learning probabilistic Latent Semantic Analysis for human motion analysis
Jin Wang 0002, Ping Liu 0004, Mary Fenghua She, Abbas Z. Kouzani, Saeid Nahavandi |
Neurocomputing | 2 |
| 2013 | Sparse representation of local spatial-temporal features with dimensionality reduction for motion recognition
Jin Wang 0002, Xiangping Sun, Ping Liu 0004, Mary Fenghua She, Lingxue Kong |
Neurocomputing | 3 |
| 2011 | Human action recognition based on Pyramid Histogram of Oriented GradientsabstractHuman action recognition has been attracted lots of interest from computer vision researchers due to its various promising applications. In this paper, we employ Pyramid Histogram of Orientation Gradient (PHOG) to characterize human figures for action recognition. Comparing to silhouette-based features, the PHOG descriptor does not require extraction of human silhouettes or contours. Two state-space models, i.e., Hidden Markov Model (HMM) and Conditional Random Field (CRF), are adopted to model the dynamic human movement. The proposed PHOG descriptor and the state-space models with respect to different parameters are tested using a standard dataset. We also testify the robustness of the method with respect to various unconstrained conditions and viewpoints. Promising experimental result demonstrates the effectiveness and robustness of our proposed method. Jin Wang 0002, Ping Liu 0004, Mary Fenghua She, Abbas Z. Kouzani, Saeid Nahavandi |
SMC | 2 |