Scaling Audio-Text Retrieval with Multimodal Large Language Models

Jilan Xu, Carl Thome, Danijela Horak, Weidi Xie, Andrew Zisserman

Visual Geometry Group, University of Oxford ยท Epidemic Sound

Technical Report

TL;DR

We propose AuroLA, a contrastive language-audio pre-training framework that repurposes a Multimodal LLM as a unified backbone for retrieval. The system builds scalable multi-granular audio captions, uses a Hybrid-NCE objective with hard-negative reweighting, and applies a bidirectional re-ranker to refine results. Experiments show consistent gains over prior audio-text retrieval SoTA, i.e., Perception Encoder Audio-Visual (PE-AV), with approximately 1% of their training data.

Visualisation

Text query: Footsteps shuffling on snow alongside a camera muffling while wind blows into a microphone
Text query: A vehicle engine revving several times with a series of compressed air releasing and plastic pops
Text query: Railroad tracks clickety-clack as a train horn blasts
Text query: Music plays continuously along with swooshing followed by a man speaking quickly
Text query: Frogs croaking and a humming with insects vocalizing

Model Architecture

AuroLA model architecture

Overall architecture of AuroLA and AuroLA-re-rank

Left: Re-purposing multimodal large language model for fast retrieval by explicit one-word limitation.

Right: Re-purposing multimodal large language model for precise re-ranking.

Results

Comparison with SOTA dual encoders

AudioCaps text-to-audio comparison Clotho text-to-audio comparison

Scaling properties of AuroLA

AudioCaps data scaling results Clotho data scaling results