Towards Fine-Grained Code-Switch Speech Translation with Semantic Space Alignment

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gao, Yan, Yang, Yazheng, Lan, Zhibin, Chen, Yidong, Zhang, Min, Wei, Daimeng, Wong, Derek F., Su, Jinsong
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913117963812864
author Gao, Yan
Yang, Yazheng
Lan, Zhibin
Chen, Yidong
Zhang, Min
Wei, Daimeng
Wong, Derek F.
Su, Jinsong
author_facet Gao, Yan
Yang, Yazheng
Lan, Zhibin
Chen, Yidong
Zhang, Min
Wei, Daimeng
Wong, Derek F.
Su, Jinsong
contents Code-switching (CS) speech translation (ST) aims to translate speech that alternates between multiple languages into a target language text, posing significant challenges due to the complexity of semantic modeling and the scarcity of CS data. Previous studies mainly rely on the models themselves to implicitly learn semantic representations and resort to costly manual annotations. To mitigate these limitations, we propose enhancing Large Language Models (LLMs) with a Mixture-of-Experts (MoE) speech projector composed of language expert groups, where each group specializes in the semantic space of a specific language for fine-grained speech feature modeling. A language-specific loss and an intra-group load balancing loss are jointly introduced to guide efficient token routing across and within expert groups. Furthermore, we introduce a multi-stage training paradigm that utilizes readily available automatic speech recognition (ASR) and monolingual ST data, facilitating speech-text alignment and improving translation performance. To bridge the data gap for smooth domain transfer, a transition loss is employed to improve adaptation to CS scenarios. Extensive experiments on widely used datasets demonstrate the effectiveness and generality of our approach, achieving average improvements of $0.86$ BLEU and $0.93$ COMET over SeamlessM4T, with maximum improvements of $1.49$ BLEU and $1.41$ COMET across different test sets.
format Preprint
id arxiv_https___arxiv_org_abs_2511_10670
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Towards Fine-Grained Code-Switch Speech Translation with Semantic Space Alignment
Gao, Yan
Yang, Yazheng
Lan, Zhibin
Chen, Yidong
Zhang, Min
Wei, Daimeng
Wong, Derek F.
Su, Jinsong
Computation and Language
Artificial Intelligence
Sound
Code-switching (CS) speech translation (ST) aims to translate speech that alternates between multiple languages into a target language text, posing significant challenges due to the complexity of semantic modeling and the scarcity of CS data. Previous studies mainly rely on the models themselves to implicitly learn semantic representations and resort to costly manual annotations. To mitigate these limitations, we propose enhancing Large Language Models (LLMs) with a Mixture-of-Experts (MoE) speech projector composed of language expert groups, where each group specializes in the semantic space of a specific language for fine-grained speech feature modeling. A language-specific loss and an intra-group load balancing loss are jointly introduced to guide efficient token routing across and within expert groups. Furthermore, we introduce a multi-stage training paradigm that utilizes readily available automatic speech recognition (ASR) and monolingual ST data, facilitating speech-text alignment and improving translation performance. To bridge the data gap for smooth domain transfer, a transition loss is employed to improve adaptation to CS scenarios. Extensive experiments on widely used datasets demonstrate the effectiveness and generality of our approach, achieving average improvements of $0.86$ BLEU and $0.93$ COMET over SeamlessM4T, with maximum improvements of $1.49$ BLEU and $1.41$ COMET across different test sets.
title Towards Fine-Grained Code-Switch Speech Translation with Semantic Space Alignment
topic Computation and Language
Artificial Intelligence
Sound
url https://arxiv.org/abs/2511.10670