Towards General-Purpose Text-Instruction-Guided Voice Conversion
Chun-Yi Kuan, Chen An Li, Tsu-Yuan Hsu, Tse-Yang Lin, Ho-Lam Chung, Kai-Wei Chang, Shuo-yiin Chang, Hung-yi Lee
TL;DR
This work introduces a text-instruction-guided voice conversion framework that operates without relying on style reference utterances. It treats voice conversion as conditional codec language modeling, encoding source speech into discrete tokens via EnCodec and generating target codes with autoregressive and non-autoregressive models conditioned on natural language instructions. The authors explore pretraining regimes (Text and TTS) and construct two datasets—the Signal Processing Effect Dataset and InstructSpeech Dataset—to enable instruction-based style control and evaluation of generalization to unseen instructions, including varying adverbs. Results show strong instruction comprehension and capable style transformation, though further work is needed to improve speech quality and diversify instruction types for broader applicability.
Abstract
This paper introduces a novel voice conversion (VC) model, guided by text instructions such as "articulate slowly with a deep tone" or "speak in a cheerful boyish voice". Unlike traditional methods that rely on reference utterances to determine the attributes of the converted speech, our model adds versatility and specificity to voice conversion. The proposed VC model is a neural codec language model which processes a sequence of discrete codes, resulting in the code sequence of converted speech. It utilizes text instructions as style prompts to modify the prosody and emotional information of the given speech. In contrast to previous approaches, which often rely on employing separate encoders like prosody and content encoders to handle different aspects of the source speech, our model handles various information of speech in an end-to-end manner. Experiments have demonstrated the impressive capabilities of our model in comprehending instructions and delivering reasonable results.
