UniVid: The Open-Source Unified Video Model
Authors: name: Jiabin Luo; name: Junhui Lin; name: Zeyu Zhang; name: Biao Wu; name: Meng Fang; name: Ling Chen; name: Hao Tang
Published: 2025-09-29 02:31:36

Abstract: Unified video modeling that combines generation and understanding
capabilities is increasingly important but faces two key challenges:
maintaining semantic faithfulness during flow-based generation due to
text-visual token imbalance and the limitations of uniform cross-modal
attention across the flow trajectory, and efficiently extending image-centric
MLLMs to video without costly retraining. We present UniVid, a unified
architecture that couples an MLLM with a diffusion decoder through a
lightweight adapter, enabling both video understanding and generation. We
introduce Temperature Modality Alignment to improve prompt adherence and
Pyramid Reflection for efficient temporal reasoning via dynamic keyframe
selection. Extensive experiments on standard benchmarks demonstrate
state-of-the-art performance, achieving a 2.2% improvement on VBench-Long total
score compared to EasyAnimateV5.1, and 1.0% and 3.3% accuracy gains on MSVD-QA
and ActivityNet-QA, respectively, compared with the best prior 7B baselines.