AAAI 2025technical0 citations

L3TC: Leveraging RWKV for Learned Lossless Low-Complexity Text Compression

Junxuan Zhang, Zhengxue Cheng, Yan Zhao, Shihao Wang, Dajiang Zhou, Guo Lu, Li Song

Abstract

Learning-based probabilistic models can be combined with an entropy coder for data compression. However, due to the high complexity of learning-based models, their practical application as text compressors has been largely overlooked. To address this issue, our work focuses on a low-complexity design while maintaining compression performance. We introduce a novel Learned Lossless Low-complexity Text Compression method (L3TC). Specifically, we conduct extensive experiments demonstrating that RWKV models achieve the fastest decoding speed with a moderate compression ratio, making it the most suitable backbone for our method. Second, we propose an outlier-aware tokenizer that uses a limited vocabulary to cover frequent tokens while allowing outliers to bypass the prediction and encoding. Third, we propose a novel high-rank reparameterization strategy that enhances the learning capability during training without increasing complexity during inference. Experimental results validate that our method achieves 48% bit saving compared to gzip compressor. Besides, L3TC offers compression performance comparable to other learned compressors, with a 50x reduction in model parameters. More importantly, L3TC is the fastest among all learned compressors, providing real-time decoding speeds up to megabytes per second.

BibTeX
@article{Zhang_Cheng_Zhao_Wang_Zhou_Lu_Song_2025, title={L3TC: Leveraging RWKV for Learned Lossless Low-Complexity Text Compression}, volume={39}, url={https://ojs.aaai.org/index.php/AAAI/article/view/33446}, DOI={10.1609/aaai.v39i12.33446}, abstractNote={Learning-based probabilistic models can be combined with an entropy coder for data compression. However, due to the high complexity of learning-based models, their practical application as text compressors has been largely overlooked. To address this issue, our work focuses on a low-complexity design while maintaining compression performance. We introduce a novel Learned Lossless Low-complexity Text Compression method (L3TC). Specifically, we conduct extensive experiments demonstrating that RWKV models achieve the fastest decoding speed with a moderate compression ratio, making it the most suitable backbone for our method. Second, we propose an outlier-aware tokenizer that uses a limited vocabulary to cover frequent tokens while allowing outliers to bypass the prediction and encoding. Third, we propose a novel high-rank reparameterization strategy that enhances the learning capability during training without increasing complexity during inference. Experimental results validate that our method achieves 48% bit saving compared to gzip compressor. Besides, L3TC offers compression performance comparable to other learned compressors, with a 50x reduction in model parameters. More importantly, L3TC is the fastest among all learned compressors, providing real-time decoding speeds up to megabytes per second.}, number={12}, journal={Proceedings of the AAAI Conference on Artificial Intelligence}, author={Zhang, Junxuan and Cheng, Zhengxue and Zhao, Yan and Wang, Shihao and Zhou, Dajiang and Lu, Guo and Song, Li}, year={2025}, month={Apr.}, pages={13251-13259} }
L3TC: Leveraging RWKV for Learned Lossless Low-Complexity Text Compression · AAAI 2025