Long-Horizon Audio-Visual Generation for Persistent Stories and Interactive Worlds

2026-08-24Computer Vision and Pattern Recognition

Computer Vision and Pattern Recognition
AI summary

The authors developed JoyAI-Echo-1.5, a new system for generating longer videos that keep characters looking and sounding consistent over time. They created two versions: one that remembers details across different clips to keep characters stable, and another that uses 3D navigation commands to let users interact with virtual worlds from different views. Their method also trains the model to handle longer video sequences efficiently, improving video quality, speech accuracy, and alignment with text descriptions. Tests show their system performs better than previous ones at maintaining story coherence and interactive control.

video generationlong-form narrativescross-shot memoryaudio-visual backbone6-DoF camera trajectoriesgeometry-aware conditioningteacher forcingself-generated rolloutstext alignmentinteractive worlds
Authors
Nan Duan, Haoyang Huang, Weiyang Jin, Haoran Li, Yaowei Li, Yuming Li, Yijun Liu, Xin Lu, Xiaoxiao Ma, Yanwen Ma, Yaofeng Su, Yilang Sun, Haoyu Wang, Zeyue Xue, Songchun Zhang, Junhao Zhuang
Abstract
Video generation is progressing beyond isolated clips toward long-form narratives and interactive worlds, requiring models to preserve identities, follow user controls, and remain stable over extended rollouts. We present JoyAI-Echo-1.5, a unified audio-visual generation system with two purpose-built variants. The long-video variant introduces composable cross-shot memory that aggregates visual evidence across multiple prior shots and speaker cues derived from speech-filtered full-shot audio, enabling persistent character appearance and voice identity across flexible combinations of text, image, and memory conditioning. The world-model variant converts heterogeneous navigation inputs into calibrated metric 6-DoF camera trajectories and injects them through a geometry-aware conditioning pathway, enabling controller-agnostic interaction across flexible viewpoints. To support efficient long-horizon generation, we transform a bidirectional audio-visual backbone into a causal few-step generator using progressive teacher forcing and short- and long-horizon Self-Gradient Forcing on self-generated rollouts. Experiments demonstrate strong performance in both settings. JoyAI-Echo-1.5 achieves improvements over existing long-video baselines in cross-shot consistency, visual quality, text alignment, and speech fidelity. Its world-model variant ranks first on WBench, with an average score of 81.7, and achieves leading visual quality and long-horizon persistence on SANA-WM-Bench. Together, these results indicate that memory, geometric control, and rollout-aware training provide a practical foundation for generating coherent stories and continuously evolving interactive worlds. Project page: https://echo-team-joy-future-academy-jd.github.io/Echo-1.5-Page/.