arXiv subjects

Yanan Chang

Publications and source records attributed to Yanan Chang.

9 recordsLinked to original sources

arXiv2026

A Novel FACS-Aligned Anatomical Text Description Paradigm for Fine-Grained Facial Behavior Synthesis

Facial behavior constitutes the primary medium of human nonverbal communication. Existing synthesis methods predominantly follow two paradigms: coarse emotion category labels or one-hot Action Unit (AU) vectors from the Facial Action Coding System (FACS). Neither paradigm reliably renders fine-grained facial behaviors nor resolves anatomically implausible artifacts caused by conflicting AUs. Therefore, we propose a novel task paradigm: anatomically grounded facial behavior synthesis from FACS-based AU descriptions. This paradigm explicitly encodes FACS-defined muscle movement rules, inter-AU interactions, and conflict resolution mechanisms into natural language control signals. To enable systematic research, we develop a dynamic AU text processor, a FACS rule-based module that converts raw AU annotations into anatomically consistent natural language descriptions. Using this processor, we construct BP4D-AUText, the first large-scale text-image paired dataset for fine-grained facial behavior synthesis, comprising over 302K high-quality samples. Given that existing general semantic consistency metrics cannot capture the alignment between anatomical facial descriptions and synthesized muscle movements, we propose the Alignment Accuracy of AU Probability Distributions (AAAD), a task-specific metric that quantifies semantic consistency. Finally, we design VQ-AUFace, a robust baseline framework incorporating anatomical priors and progressive cross-modal alignment, to validate the paradigm. Extensive quantitative experiments and user studies demonstrate the paradigm significantly outperforms state-of-the-art methods, particularly in challenging conflicting AU scenarios, achieving superior anatomical fidelity, semantic consistency, and visual quality.

cs.CV↗

arXiv2025

Large Language Models for Education: ChemTAsk -- An Open-Source Paradigm for Automated Q&A in the Graduate Classroom

Large language models (LLMs) show promise for aiding graduate level education, but are limited by their training data and potential confabulations. We developed ChemTAsk, an open-source pipeline that combines LLMs with retrieval-augmented generation (RAG) to provide accurate, context-specific assistance. ChemTAsk utilizes course materials, including lecture transcripts and primary publications, to generate accurate responses to student queries. Over nine weeks in an advanced biological chemistry course at the University of Pennsylvania, students could opt in to use ChemTAsk for assistance in any assignment or to understand class material. Comparative analysis showed ChemTAsk performed on par with human teaching assistants (TAs) in understanding student queries and providing accurate information, particularly excelling in creative problem-solving tasks. In contrast, TAs were more precise in their responses and tailored their assistance to the specifics of the class. Student feedback indicated that ChemTAsk was perceived as correct, helpful, and faster than TAs. Open-source and proprietary models from Meta and OpenAI respectively were tested on an original biological chemistry benchmark for future iterations of ChemTAsk. It was found that OpenAI models were more tolerant to deviations in the input prompt and excelled in self-assessment to safeguard for potential confabulations. Taken together, ChemTAsk demonstrates the potential of integrating LLMs with RAG to enhance educational support, offering a scalable tool for students and educators.

cs.CY↗

arXiv2023

MEDIC: A Multimodal Empathy Dataset in Counseling

Although empathic interaction between counselor and client is fundamental to success in the psychotherapeutic process, there are currently few datasets to aid a computational approach to empathy understanding. In this paper, we construct a multimodal empathy dataset collected from face-to-face psychological counseling sessions. The dataset consists of 771 video clips. We also propose three labels (i.e., expression of experience, emotional reaction, and cognitive reaction) to describe the degree of empathy between counselors and their clients. Expression of experience describes whether the client has expressed experiences that can trigger empathy, and emotional and cognitive reactions indicate the counselor's empathic reactions. As an elementary assessment of the usability of the constructed multimodal empathy dataset, an interrater reliability analysis of annotators' subjective evaluations for video clips is conducted using the intraclass correlation coefficient and Fleiss' Kappa. Results prove that our data annotation is reliable. Furthermore, we conduct empathy prediction using three typical methods, including the tensor fusion network, the sentimental words aware fusion network, and a simple concatenation model. The experimental results show that empathy can be well predicted on our dataset. Our dataset is available for research purposes.

cs.CV↗

arXiv2023

Facial Affective Behavior Analysis Method for 5th ABAW Competition

Facial affective behavior analysis is important for human-computer interaction. 5th ABAW competition includes three challenges from Aff-Wild2 database. Three common facial affective analysis tasks are involved, i.e. valence-arousal estimation, expression classification, action unit recognition. For the three challenges, we construct three different models to solve the corresponding problems to improve the results, such as data unbalance and data noise. For the experiments of three challenges, we train the models on the provided training data and validate the models on the validation data.

cs.CV↗

arXiv2023

Emotional Reaction Intensity Estimation Based on Multimodal Data

This paper introduces our method for the Emotional Reaction Intensity (ERI) Estimation Challenge, in CVPR 2023: 5th Workshop and Competition on Affective Behavior Analysis in-the-wild (ABAW). Based on the multimodal data provided by the originazers, we extract acoustic and visual features with different pretrained models. The multimodal features are mixed together by Transformer Encoders with cross-modal attention mechnism. In this paper, 1. better features are extracted with the SOTA pretrained models. 2. Compared with the baseline, we improve the Pearson's Correlations Coefficient a lot. 3. We process the data with some special skills to enhance performance ability of our model.

cs.CV↗

arXiv2022

Hand-Assisted Expression Recognition Method from Synthetic Images at the Fourth ABAW Challenge

Learning from synthetic images plays an important role in facial expression recognition task due to the difficulties of labeling the real images, and it is challenging because of the gap between the synthetic images and real images. The fourth Affective Behavior Analysis in-the-wild Competition raises the challenge and provides the synthetic images generated from Aff-Wild2 dataset. In this paper, we propose a hand-assisted expression recognition method to reduce the gap between the synthetic data and real data. Our method consists of two parts: expression recognition module and hand prediction module. Expression recognition module extracts expression information and hand prediction module predicts whether the image contains hands. Decision mode is used to combine the results of two modules, and post-pruning is used to improve the result. F1 score is used to verify the effectiveness of our method.

cs.CV↗

arXiv2022

Multi-Task Learning for Emotion Descriptors Estimation at the fourth ABAW Challenge

Facial valence/arousal, expression and action unit are related tasks in facial affective analysis. However, the tasks only have limited performance in the wild due to the various collected conditions. The 4th competition on affective behavior analysis in the wild (ABAW) provided images with valence/arousal, expression and action unit labels. In this paper, we introduce multi-task learning framework to enhance the performance of three related tasks in the wild. Feature sharing and label fusion are used to utilize their relations. We conduct experiments on the provided training and validating data.

cs.CV↗

arXiv2022

Facial Action Unit Recognition Based on Transfer Learning

Facial action unit recognition is an important task for facial analysis. Owing to the complex collection environment, facial action unit recognition in the wild is still challenging. The 3rd competition on affective behavior analysis in-the-wild (ABAW) has provided large amount of facial images with facial action unit annotations. In this paper, we introduce a facial action unit recognition method based on transfer learning. We first use available facial images with expression labels to train the feature extraction network. Then we fine-tune the network for facial action unit recognition.

cs.CV↗

arXiv2021

Exploring Adversarial Learning for Deep Semi-Supervised Facial Action Unit Recognition

Current works formulate facial action unit (AU) recognition as a supervised learning problem, requiring fully AU-labeled facial images during training. It is challenging if not impossible to provide AU annotations for large numbers of facial images. Fortunately, AUs appear on all facial images, whether manually labeled or not, satisfy the underlying anatomic mechanisms and human behavioral habits. In this paper, we propose a deep semi-supervised framework for facial action unit recognition from partially AU-labeled facial images. Specifically, the proposed deep semi-supervised AU recognition approach consists of a deep recognition network and a discriminator D. The deep recognition network R learns facial representations from large-scale facial images and AU classifiers from limited ground truth AU labels. The discriminator D is introduced to enforce statistical similarity between the AU distribution inherent in ground truth AU labels and the distribution of the predicted AU labels from labeled and unlabeled facial images. The deep recognition network aims to minimize recognition loss from the labeled facial images, to faithfully represent inherent AU distribution for both labeled and unlabeled facial images, and to confuse the discriminator. During training, the deep recognition network R and the discriminator D are optimized alternately. Thus, the inherent AU distributions caused by underlying anatomic mechanisms are leveraged to construct better feature representations and AU classifiers from partially AU-labeled data during training. Experiments on two benchmark databases demonstrate that the proposed approach successfully captures AU distributions through adversarial learning and outperforms state-of-the-art AU recognition work.

cs.CV↗