Prompting Large Language Models with Speech Recognition Abilities
Yassir Fathullah Chunyang Wu Egor Lakomkin Junteng Jia Yuan Shangguan Ke Li Jinxi Guo Wenhan Xiong Jay Mahadeokar Ozlem Kalinli Christian Fuegen Mike Seltzer
Large language models have proven themselves highly flexible, able to solve a
wide range of generative tasks, such as abstractive summarization and
open-ended question answering. In this paper we extend the capabilities of LLMs
by directly attaching a small audio encoder allowing it to perform speech
recognition. By directly prepending a sequence of audial embeddings to the text
token embeddings, the LLM can be converted to an automatic speech recognition
(ASR) system, and be used in the exact same manner as its textual counterpart.
Experiments on Multilingual LibriSpeech (MLS) show that incorporating a
conformer encoder into the open sourced LLaMA-7B allows it to outperform
monolingual baselines by 18% and perform multilingual speech recognition
despite LLaMA being trained overwhelmingly on English text. Furthermore, we
perform ablation studies to investigate whether the LLM can be completely
frozen during training to maintain its original capabilities, scaling up the
audio encoder, and increasing the audio encoder striding to generate fewer
embeddings. The results from these studies show that multilingual ASR is
possible even when the LLM is frozen or when strides of almost 1 second are
used in the audio encoder opening up the possibility for LLMs to operate on
long-form audio.