MusicWeaver: Composer-Style Structural Editing and Minute-Scale Coherent Music Generation

Recent advances in music generation produce impressive samples, however, practical creation still lacks two key capabilities: composer-style structural editing and minute-scale coherence. We present MusicWeaver, a framework for generating and editing long-range music using a human-interpretable intermediate representation with guaranteed edit locality. MusicWeaver decomposes generation into two stages: it first predicts a structured plan, a multi-level song program encoding musical attributes that composers can directly edit, and then renders audio conditioned on this plan. To ensure minute-scale coherence, we introduce a Global-Local Diffusion Transformer, where a global path captures long-range musical progression via compressed representations and memory, while a local path synthesizes fine-grained acoustic detail. We further propose a Motif Memory Retrieval module that enables consistent motif recurrence with controllable variation. For editing, we propose Projected Diffusion Inpainting, an inpainting method that denoises only user-specified regions and preserves unchanged content, allowing repeated edits without drift. Finally, we introduce Structure Coherence Score and Edit Fidelity Score to evaluate long-range form and edit realization. Experiments demonstrate that MusicWeaver achieves state-of-the-art fidelity, controllability, and long-range coherence.