McGill-NLP/NaijaS2ST

Multilingual Speech Dataset (Speech-to-Speech / Speech-to-Text Ready)

The IWSLT shared task submission details and the test set are now available at [IWSLT 2026](https://iwslt.org/2026/african-celtic)

Dataset Summary

This dataset is a large-scale multilingual speech corpus curated for speech-to-speech translation, speech-to-text, and multilingual speech processing research. The data is organized by language, speaker (`user_id`), and dataset split (train, dev), and includes rich acoustic and metadata annotations.

The dataset is published and maintained by Marie Maltais at mcgill-NLP.

Languages

The dataset currently includes speech data in the following languages:

• —Yoruba (`Y`)
• —Naija Pidgin (`P`)
• —Igbo (`I`)
• —Hausa (`H`)
• —English (`E`)

Additional languages may be added in future releases.

Accented English

The dataset currently includes English accents, the accent code is represented by the first two characters in the `user_id` field as such:

• —Northern Nigerian English (`EN`)
• —Southern Nigerian English (`EY`)
• —British Nigerian English (`EB`)

Dataset Organization

Hugging Face Representation

On Hugging Face, the dataset is exposed as a flattened DatasetDict with the following splits:

• —train
• —dev

Each row corresponds to a single utterance, with speaker, language, text, and acoustic metadata preserved.

Data Fields

Each example contains the following fields (aligned with dataset_info):

Audio Specifications

• —Sampling rate (served): 48,000 Hz
• —Format: WAV
• —Channels: Mono

Original sampling rates are preserved in the original_sample_rate field.

Intended Uses

Primary Use Cases

• —Speech-to-speech translation
• —Speech-to-text and ASR
• —Multilingual and low-resource speech modeling

Data Processing

• —Audio segmented at the utterance level
• —Speaker boundaries preserved via user_id
• —Acoustic metrics computed automatically
• —No forced alignment or phonetic labeling applied
• —Text is provided as reference only and may contain natural speech variation

Licensing

This dataset is released under the Creative Commons Attribution 4.0 International (CC BY 4.0) license unless otherwise stated.

Users must provide appropriate attribution when using this dataset.

Citation

If you use this dataset in academic or industrial research, please cite:

@misc{maltais2026naijas2stmultiaccentbenchmarkspeechtospeech,
      title={NaijaS2ST: A Multi-Accent Benchmark for Speech-to-Speech Translation in Low-Resource Nigerian Languages}, 
      author={Marie Maltais and Yejin Jeon and Min Ma and Shamsuddeen Hassan Muhammad and Idris Abdulmumin and Maryam Ibrahim Mukhtar and Daud Abolade and Joel Okepefi and Johnson Sewedo and David Ifeoluwa Adelani},
      year={2026},
      eprint={2604.16287},
      archivePrefix={arXiv},
      primaryClass={cs.SD},
      url={https://arxiv.org/abs/2604.16287}, 
}

Contact and Maintenance

For issues, questions, or contributions, please use the Hugging Face dataset repository under mcgill-NLP.