Controllable Embedding Transformation for Mood-Guided Music Retrieval
Julia Wilkins, Jaehun Kim, Matthew E. P. Davies, Juan Pablo Bello, Matthew C. McCallum
TL;DR
This work tackles mood-controlled music retrieval by learning a transformation in the embedding space that moves a seed track toward a target mood while preserving non-mood attributes like genre and instrumentation. It introduces a novel nearest-neighbor sampling scheme to generate proxy mood-target embeddings and trains a lightweight translator in the MULE embedding space using a joint objective with three complementary losses. Across a large proprietary dataset and MTG-Jamendo, the method achieves strong mood transformation while substantially preserving seed information, outperforming training-free baselines and approaching Oracle upper bounds. The approach generalizes to zero-shot scenarios and suggests promising directions for extending controllability to multi-mood settings and cross-modal guidance. This work establishes controllable embedding transformation as a viable paradigm for scalable, attribute-guided music retrieval.
Abstract
Music representations are the backbone of modern recommendation systems, powering playlist generation, similarity search, and personalized discovery. Yet most embeddings offer little control for adjusting a single musical attribute, e.g., changing only the mood of a track while preserving its genre or instrumentation. In this work, we address the problem of controllable music retrieval through embedding-based transformation, where the objective is to retrieve songs that remain similar to a seed track but are modified along one chosen dimension. We propose a novel framework for mood-guided music embedding transformation, which learns a mapping from a seed audio embedding to a target embedding guided by mood labels, while preserving other musical attributes. Because mood cannot be directly altered in the seed audio, we introduce a sampling mechanism that retrieves proxy targets to balance diversity with similarity to the seed. We train a lightweight translation model using this sampling strategy and introduce a novel joint objective that encourages transformation and information preservation. Extensive experiments on two datasets show strong mood transformation performance while retaining genre and instrumentation far better than training-free baselines, establishing controllable embedding transformation as a promising paradigm for personalized music retrieval.
