Eton-ASR-Dataset

Language

Eton is a Narrow Bantu language belonging to the Beti-Fang group of the Benue-Congo branch. It is indigenous to a population located primarily in the Centre Region of Cameroon, particularly in the Nyong-et-Kellé, Lekié and Mefou-et-Afamba Divisions. Eton is closely related to Ewondo and other Beti-Fang languages such as Bulu, Ntumu and Fang. Ethnologue estimates the number of speakers at approximately 120,000. Despite its linguistic significance as a Beti-Fang variety, Eton remains significantly underrepresented in language technology resources.

Variants

The glossonym 'Eton' designates a relatively homogeneous linguistic variety within the Beti-Fang macro-language, as classified in the framework of the Atlas Linguistique du Cameroun (ALCAM) project. Eton is listed as one of the major micro-languages of the Beti-Fang group alongside Ewondo, Fang, Bulu and Ntumu. Local variation exists across the different chieftaincies of the Eton-speaking area, though these do not constitute recognised sub-varieties in standard linguistic classifications.

The present dataset represents speakers of the Eton variety as spoken in the Yaoundé area (Centre Region), recruited at the École Normale Supérieure de Yaoundé.

Writing System

The writing system used for the transcription of Eton in this dataset is the General Alphabet of Cameroon's Languages (AGLC), as adopted by the Ministry of Basic Education of Cameroon and regularly updated by the Direction de la Promotion des Langues Nationales. The AGLC provides a phonologically motivated orthographic standard for Cameroonian national languages and serves as the reference framework for Eton literacy materials.

1. Vowels

The vowel system attested in the dataset includes the following oral vowels:

a, e, ə, i, o, u, ɔ

Long vowels are represented by vowel doubling (e.g. aa, ee, oo).

2. Consonants

The consonant inventory reflected in the dataset includes simple, prenasalized and digraph consonants:

b, d, dz, f, g, gb, h, k, kp, l, m, mb, mv, n, nd, ng, nk, nz, ny, ŋ, p, s, t, ts, v, w, y, z

Special symbols: ə (mid central vowel), ŋ (velar nasal), gb and kp (labial-velar consonants)

3. Tone system

Eton is a tonal language with lexical and grammatical contrastive tones. The dataset employs systematic tone marking on vowels in accordance with the AGLC convention:

• High tone (H): á, é, ə́, í, ó, ɔ́, ú

• Low tone (L): à, è, ə̀, ì, ò, ɔ̀, ù

• Falling tone (HL): â, ê, ə̂, î, ô, ɔ̂, û

• Rising tone (LH): ǎ, ě, ə̌, ǐ, ǒ, ɔ̌, ǔ

Unmarked vowels represent tonally neutral or contextually determined syllables. This explicit tone notation distinguishes the present dataset from the Common Voice Scripted Speech 25.0 – Eton resource, in which tone diacritics are systematically absent.

Source

The dataset was compiled from scripted speech prompt lists read by native speakers of Eton in recording sessions held at the École Normale Supérieure de Yaoundé in 2026, in the framework of the Mozilla Data Collective project. Sentences were selected to provide broad phonological coverage of Eton and were transcribed in accordance with the AGLC orthographic standard, with full tone marking.

Domain

The dataset represents scripted speech in Eton, covering a broad range of everyday sentence types drawn from a general-purpose ASR/TTS prompt list. All utterances are scripted rather than spontaneous.

Size

Total audio duration: 12,896 seconds (03:34:56), distributed across 1,402 MP3 audio clips in 15 recording sessions contributed by 11 native speakers of Eton.

Structure

The dataset comprises:

1. 1,402 MP3 audio clips read by 11 native speakers of Eton, with a total duration of 12,896 seconds (03:34:56), distributed across 15 recording sessions:

   • Session eto_01: 99 clips (09m 42s)

   • Session eto_01-1: 99 clips (12m 51s)

   • Session eto_02: 100 clips (14m 50s)

   • Session eto_02-1: 100 clips (11m 16s)

   • Session eto_04: 100 clips (12m 55s)

   • Session eto_05: 100 clips (16m 41s)

   • Session eto_08-1: 100 clips (19m 06s)

   • Session eto_08-2: 100 clips (21m 53s)

   • Session eto_8-3: 100 clips (15m 21s)

   • Session eto_10: 100 clips (11m 38s)

   • Session eto_13: 100 clips (17m 12s)

   • Session eto_16: 100 clips (16m 14s)

   • Session eto_17: 100 clips (11m 53s)

   • Session eto_18: 100 clips (22m 26s)

   • Session eto_19: 4 clips (00m 52s)

2. Fifteen per-session sentence-to-audio mapping files (mapping.tsv), each with 4 columns.

Description of columns (mapping.tsv)

• #audio_filename: filename of the audio clip (MP3)

• #key: unique hash identifier of the recording

• #sentence: sentence text as read by the speaker, transcribed in AGLC orthography with tone marking

• #attempts: number of recording attempts before acceptance

Sample