LiteASR: Efficient Automatic Speech Recognition with Low-Rank Approximation
Keisuke Kamahori, Jungo Kasai, Noriyuki Kojima, Baris Kasikci
Abstract
Modern automatic speech recognition (ASR) models, such as OpenAI’s Whisper, rely on deep encoder-decoder architectures, and their encoders are a critical bottleneck for efficient deployment due to high computational intensity. We introduce LiteASR, a low-rank compression scheme for ASR encoders that significantly reduces inference costs while maintaining transcription accuracy. Our approach leverages the strong low-rank properties observed in intermediate activations: by applying principal component analysis (PCA) with a small calibration dataset, we approximate linear transformations with a chain of low-rank matrix multiplications, and further optimize self-attention to work in reduced dimensionality. Evaluation results show that our method can compress Whisper large-v3’s encoder size by over 50%, matching Whisper medium’s size with better transcription accuracy, thereby establishing a new Pareto frontier of accuracy and efficiency. The code of LiteASR is available at https://github.com/efeslab/LiteASR.- Anthology ID:
- 2025.emnlp-main.169
- Volume:
- Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
- Month:
- November
- Year:
- 2025
- Address:
- Suzhou, China
- Editors:
- Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
- Venue:
- EMNLP
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 3430–3442
- Language:
- URL:
- https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.169/
- DOI:
- Cite (ACL):
- Keisuke Kamahori, Jungo Kasai, Noriyuki Kojima, and Baris Kasikci. 2025. LiteASR: Efficient Automatic Speech Recognition with Low-Rank Approximation. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 3430–3442, Suzhou, China. Association for Computational Linguistics.
- Cite (Informal):
- LiteASR: Efficient Automatic Speech Recognition with Low-Rank Approximation (Kamahori et al., EMNLP 2025)
- PDF:
- https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.169.pdf