PRLab @ Nanjing University

About

Chenyang Si is a Tenure-Track Associate Professor at the School of Intelligence Science and Technology, Nanjing University. Prior to this, he was a Research Fellow at Nanyang Technological University (NTU), Singapore, working with Prof. Ziwei Liu. Before that, he worked as a Research Scientist at the Sea AI Lab of Sea Group. He received his Ph.D. degree in 2021 from CASIA, supervised by Prof. Tieniu Tan, co-supervised by Prof. Liang Wang and Prof. Wei Wang.

His research interests span visual understanding and generation, including fundamental architectures for computer vision, video understanding, generative models, video and image generation, as well as acceleration and optimization of generative models.

Research Interests

Video Generation Diffusion Models Visual Understanding Efficient AI Image Editing & Morphing Evaluation Benchmarks

Academic Services

Conference Area Chair

BMVC 2024 BMVC 2025 CVPR 2026

Conference Reviewer

CVPR ICCV NeurIPS ECCV AAAI ICLR

Journal Reviewer

TPAMI TIP TMM TCSVT IJCV

Research Directions

Video Generation

We study generative models for high-quality and controllable video synthesis, including diffusion-based video models, consistency models, and efficient video generation architectures.

RepVideo Vchitect-2.0 LaVie

Generative Models

We explore diffusion models and AIGC for image and multimodal generation, covering image editing, morphing, controllable generation, and 3D-aware content creation.

FreeU FreeInit DaS VideoBooth

Visual Understanding

We develop fundamental vision architectures (e.g., MetaFormer) and methods for action recognition, skeleton-based understanding, and vision-language navigation.

MetaFormer iFormer Semantic Prompt

Efficient AI

We investigate training-free and training-based acceleration methods for large generative models, reducing inference cost while maintaining generation quality.

FasterCache DCM

Evaluation & Benchmarks

We design comprehensive evaluation benchmarks for video generative models (e.g., VBench) to enable systematic and fair assessment of generation quality.

VBench VBench++

Recent News

2025.07

DCM (Dual-Expert Consistency Model for Efficient Video Generation) and TACA (Cross-Modal Interaction in Multimodal Diffusion Transformers) are accepted by ICCV 2025. Congratulations!

2025.07

FreeMorph (Tuning-Free Generalized Image Morphing with Diffusion Model) is accepted by ICCV 2025. Congratulations!

2025.05

DaS (Diffusion as Shader: 3D-aware Video Diffusion) is accepted by SIGGRAPH 2025 Conference Track and selected in the SIGGRAPH Video Trailer!

PDF Project

2025.01

FasterCache (Training-Free Video Diffusion Model Acceleration) is accepted by ICLR 2025.

PDF Project

2025.01

RepVideo (Rethinking Cross-Layer Representation for Video Generation) is released on arXiv.

PDF Project Code

2024.09

MAN (Momentum Auxiliary Network for Supervised Local Learning) is accepted by ECCV 2024 as an Oral presentation. Congratulations!

2024.07

FreeInit, HPFF are accepted by ECCV 2024. Congratulations!

2024.02

FreeU is accepted by CVPR 2024 as an Oral presentation, and VBench is accepted as a Highlight. Congratulations!

FreeU Project VBench Project

2024.01

PRLab is established at the School of Intelligence Science and Technology, Nanjing University. Welcome to join us!

Lab Members

Chenyang Si

Principal Investigator · Associate Professor

Prof. Chenyang Si is a Tenure-Track Associate Professor at the School of Intelligence Science and Technology, Nanjing University. He was a Research Fellow at NTU and a Research Scientist at Sea AI Lab. He received his Ph.D. from CASIA in 2021. His research interests span visual understanding and generation, including video generation, diffusion models, and generative model acceleration.

Video Generation Diffusion Models Visual Understanding Efficient AI

Homepage Scholar Email

Former Members

Publications

RepVideo: Rethinking Cross-Layer Representation for Video Generation

Chenyang Si, Weichen Fan, Zhengyao Lv, Ziqi Huang, Yu Qiao, Ziwei Liu

arXiv 2025

PDF Project Code

Vchitect-2.0: Parallel Transformer for Scaling Up Video Diffusion Models

Weichen Fan, Chenyang Si, Junhao Song, Zhenyu Yang, Yinan He, Long Zhuo, Ziqi Huang, Ziyue Dong, Jingwen He, Dongwei Pan, Yi Wang, Yuming Jiang, Yaohui Wang, Peng Gao, Xinyuan Chen, Hengjie Li, Dahua Lin, Yu Qiao, Ziwei Liu

arXiv 2025

PDF Project Code

GOOD: Training-Free Guided Diffusion Sampling for Out-of-Distribution Detection

Xin Gao, Jiyao Liu, Guanghao Li, Yueming Lyu, Jianxiong Gao, Weichen Yu, Ningsheng Xu, Liang Wang, Caifeng Shan, Ziwei Liu, Chenyang Si

NeurIPS 2025

PDF

DCM: Dual-Expert Consistency Model for Efficient and High-Quality Video Generation

Zhengyao Lv, Chenyang Si, Tianlin Pan, Zhaoxi Chen, Kwan-Yee K. Wong, Yu Qiao, Ziwei Liu

ICCV 2025

PDF Project Code

TACA: Rethinking Cross-Modal Interaction in Multimodal Diffusion Transformers

Zhengyao Lv, Tianlin Pan, Chenyang Si, Zhaoxi Chen, Wangmeng Zuo, Ziwei Liu, Kwan-Yee K. Wong

ICCV 2025

PDF Project Code

FreeMorph: Tuning-Free Generalized Image Morphing with Diffusion Model

Yukang Cao, Chenyang Si, Jinghao Wang, Ziwei Liu

ICCV 2025

PDF

Diffusion as Shader: 3D-aware Video Diffusion for Versatile Video Generation Control

Zekai Gu, Rui Yan, Jiahao Lu, Peng Li, Zhiyang Dou, Chenyang Si, Zhen Dong, Qifeng Liu, Cheng Lin, Ziwei Liu, Wenping Wang, Yuan Liu

SIGGRAPH 2025 Video Trailer

PDF Project Code

VBench++: Comprehensive and Versatile Benchmark Suite for Video Generative Models

Ziqi Huang, Fan Zhang, Xiaojie Xu, Yinan He, Jiashuo Yu, Ziyue Dong, Qianli Ma, Nattapol Chanpaisit, Chenyang Si, Yuming Jiang, Yaohui Wang, Xinyuan Chen, Ying-Cong Chen, Limin Wang, Dahua Lin, Yu Qiao, Ziwei Liu

arXiv 2025

PDF Project Code

FasterCache: Training-Free Video Diffusion Model Acceleration with High Quality

Zhengyao Lv, Chenyang Si, Junhao Song, Zhenyu Yang, Yu Qiao, Ziwei Liu, Kwan-Yee K. Wong

ICLR 2025

PDF Project Code

FreeInit: Bridging Initialization Gap in Video Diffusion Models

Tianxing Wu, Chenyang Si, Yuming Jiang, Ziqi Huang, Ziwei Liu

ECCV 2024

PDF Project Code Video

Momentum Auxiliary Network for Supervised Local Learning

Junhao Su, Changpeng Cai, Feiyu Zhu, Chenghao He, Xiaojie Xu, Dongzhi Guan, Chenyang Si

ECCV 2024 Oral

PDF Code

HPFF: Hierarchical Locally Supervised Learning with Patch Feature Fusion

Junhao Su, Chenghao He, Feiyu Zhu, Xiaojie Xu, Dongzhi Guan, Chenyang Si

ECCV 2024

PDF Code

FreeU: Free Lunch in Diffusion U-Net

Chenyang Si, Ziqi Huang, Yuming Jiang, Ziwei Liu

CVPR 2024 Oral

PDF Project Code Video

VBench: Comprehensive Benchmark Suite for Video Generative Models

Ziqi Huang, Yinan He, Jiashuo Yu, Fan Zhang, Chenyang Si, Yuming Jiang, Yuanhan Zhang, Tianxing Wu, Qingyang Jin, Nattapol Chanpaisit, Yaohui Wang, Xinyuan Chen, Limin Wang, Dahua Lin, Yu Qiao, Ziwei Liu

CVPR 2024 Highlight

PDF Project Code

VideoBooth: Diffusion-based Video Generation with Image Prompts

Yuming Jiang, Tianxing Wu, Shuai Yang, Chenyang Si, Dahua Lin, Yu Qiao, Chen Change Loy, Ziwei Liu

CVPR 2024

PDF Project Code

Towards Language-Driven Video Inpainting via Multimodal Large Language Models

Jianzong Wu, Xiangtai Li, Chenyang Si, Shangchen Zhou, Jingkang Yang, Jiangning Zhang, Yining Li, Kai Chen, Yunhai Tong, Ziwei Liu, Chen Change Loy

CVPR 2024

PDF Project Code

Scaling Supervised Local Learning with Augmented Auxiliary Networks

Chenxiang Ma, Jibin Wu, Chenyang Si, KC Tan

ICLR 2024

PDF Code

LaVie: High-Quality Video Generation with Cascaded Latent Diffusion Models

Yaohui Wang, Xinyuan Chen, Xin Ma, Shangchen Zhou, Ziqi Huang, Yi Wang, Ceyuan Yang, Yinan He, Jiashuo Yu, Peiqing Yang, Yuwei Guo, Tianxing Wu, Chenyang Si, Yuming Jiang, Cunjian Chen, Chen Change Loy, Bo Dai, Dahua Lin, Yu Qiao, Ziwei Liu

IJCV 2024

PDF Project Code

Frequency-Enhanced Data Augmentation for Vision-and-Language Navigation

Keji He, Chenyang Si, Zhihe Lu, Yan Huang, Liang Wang, Xinchao Wang

NeurIPS 2023

PDF Code

FSAR: Federated Skeleton-based Action Recognition with Adaptive Topology Structure and Knowledge Distillation

Jingwen Guo, Hong Liu, Shitong Sun, Tianyu Guo, Min Zhang, Chenyang Si

ICCV 2023

PDF

Semantic Prompt for Few-Shot Learning

Wentao Chen*, Chenyang Si*, Zhang Zhang, Liang Wang, Zilei Wang, Tieniu Tan (Equal contribution)

CVPR 2023

PDF Code

MetaFormer Baselines for Vision

Weihao Yu, Chenyang Si, Pan Zhou, Mi Luo, Yichen Zhou, Jiashi Feng, Shuicheng Yan, Xinchao Wang

TPAMI 2023

PDF Code

Federated Zero-Shot Learning with Mid-Level Semantic Knowledge Transfer

Shitong Sun, Chenyang Si, Shaogang Gong, Guile Wu

Pattern Recognition 2023

PDF

Inception Transformer

Chenyang Si, Weihao Yu, Pan Zhou, Yichen Zhou, Xinchao Wang, Shuicheng Yan

NeurIPS 2022 Oral

PDF Code

Mugs: A Multi-Granular Self-Supervised Learning Framework

Pan Zhou, Yichen Zhou, Chenyang Si, Weihao Yu, Teck Khim Ng, Shuicheng Yan

NeurIPS Workshop 2022

PDF Code

Contrast-Reconstruction Representation Learning for Self-supervised Skeleton-based Action Recognition

Peng Wang, Jun Wen, Chenyang Si, Yuntao Qian, Liang Wang

TIP 2022

PDF

MetaFormer is Actually What You Need for Vision

Weihao Yu, Mi Luo, Pan Zhou, Chenyang Si, Yichen Zhou, Xinchao Wang, Jiashi Feng, Shuicheng Yan

CVPR 2022 Oral

PDF Code

Generalizable Person Re-Identification via Self-Supervised Batch Norm Test-Time Adaption

Ke Han, Chenyang Si, Yan Huang, Liang Wang, Tieniu Tan

AAAI 2022

PDF

Few-Shot Learning with Part Discovery and Augmentation from Unlabeled Images

Wentao Chen, Chenyang Si, Wei Wang, Liang Wang, Zilei Wang, Tieniu Tan

IJCAI 2021

PDF

Adversarial Self-Supervised Learning for Semi-Supervised 3D Action Recognition

Chenyang Si, Xuecheng Nie, Wei Wang, Liang Wang, Tieniu Tan, Jiashi Feng

ECCV 2020

PDF Video

Skeleton-Based Action Recognition with Hierarchical Spatial Reasoning and Temporal Stack Learning Network

Chenyang Si, Ya Jing, Wei Wang, Liang Wang, Tieniu Tan

Pattern Recognition 2020

PDF

Pose-Guided Multi-Granularity Attention Network for Text-Based Person Search

Ya Jing, Chenyang Si, Junbo Wang, Wei Wang, Liang Wang, Tieniu Tan

AAAI 2020 Oral

PDF

An Attention Enhanced Graph Convolutional LSTM Network for Skeleton-Based Action Recognition

Chenyang Si, Wentao Chen, Wei Wang, Liang Wang, Tieniu Tan

CVPR 2019

PDF

Skeleton-Based Action Recognition with Spatial Reasoning and Temporal Stack Learning

Chenyang Si, Ya Jing, Wei Wang, Liang Wang, Tieniu Tan

ECCV 2018

PDF

Multistage Adversarial Losses for Pose-Based Human Image Synthesis

Chenyang Si, Wei Wang, Liang Wang, Tieniu Tan

CVPR 2018 Spotlight

PDF

Pose-Based Two-Stream Relational Networks for Action Recognition in Videos

Wei Wang, Jinjin Zhang, Chenyang Si, Liang Wang

Tech Report 2018

PDF

Join Us

We are actively seeking highly motivated students and researchers to join PRLab at Nanjing University. Our lab focuses on cutting-edge research in visual understanding and generation, with a particular emphasis on video generation and diffusion models. If you are interested in applying, please refer to this Zhihu Post and fill out the Google Form.

Ph.D. Students

Recruiting for 2027 Fall (普博 / 直博)
Strong CS / AI background
Solid Python and PyTorch skills
Passion for computer vision research
Good English communication

Master's Students

Recruiting for 2027 Fall (保研 / 考研)
Undergraduate in CS or related fields
Strong math foundation
Deep learning framework experience
Collaborative and self-driven

Research Interns

Undergraduate / visiting students
At least 3–6 months commitment
Prior research experience preferred
Remote or on-site both welcome
Future Ph.D. applicants encouraged

Interested in joining PRLab?

Please send your CV and a brief research statement. We look forward to hearing from you.

chenyang.si@nju.edu.cn