Tupuri-ASR-Dataset

Language

Tupuri is a Chadic language belonging to the Afro-Asiatic phylum, classified within the Biu-Mandara branch. It is indigenous to communities located primarily in the Adamawa and North Regions of Cameroon (particularly the Faro-et-Déo and Mayo-Rey Divisions) and in the southern part of Chad (Mayo-Kebbi region). Tupuri is closely related to other Chadic languages of the same area. Ethnologue estimates the number of speakers at approximately 300,000. Despite its significant speaker population, Tupuri remains substantially underrepresented in language technology resources.

Variants

Tupuri presents a number of geographically distributed dialectal varieties. The present dataset covers two principal dialects:

• Bango dialect: spoken in the Bango area of the Adamawa Region of Cameroon.

• Banwere dialect: spoken in the Banwere area of the Adamawa Region of Cameroon.

These two varieties exhibit phonological and prosodic differences that are reflected in the recorded speech and transcriptions. Each dialect is represented as a distinct subset of the dataset, enabling dialect-sensitive modelling and analysis.

Writing System

The writing system used for the transcription of Tupuri 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 Tupuri literacy materials.

1. Vowels

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

a, e, ɛ, i, o, ɔ, u

Nasalised vowels are represented with a tilde diacritic (e.g. ã, ẽ, ĩ, õ, ũ). Long vowels are represented by vowel doubling (e.g. aa, ee, oo).

2. Consonants

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

b, ɓ, c, d, ɗ, f, g, gb, h, j, k, kp, l, m, mb, n, nd, ng, nj, ŋ, p, r, s, t, w, y

Special symbols: ɓ (bilabial implosive), ɗ (alveolar implosive), ŋ (velar nasal), gb and kp (labial-velar consonants)

3. Tone system

Tupuri 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, ɛ́, í, ó, ɔ́, ú

• Low tone (L): à, è, ɛ̀, ì, ò, ɔ̀, ù

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

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

Source

The dataset was compiled from scripted speech prompt lists read by native speakers of Tupuri 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 Tupuri across both dialects and were transcribed in accordance with the AGLC orthographic standard.

Domain

The dataset represents scripted speech in Tupuri (Bango and Banwere dialects), 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: 8,630 seconds (02h 23m 50s), distributed across 1,800 MP3 audio clips in 18 recording sessions contributed by 16 native speakers of Tupuri.

• Bango subset: 2,442 seconds (00h 40m 42s), 700 MP3 clips, 7 sessions.

• Banwere subset: 6,188 seconds (01h 43m 08s), 1,100 MP3 clips, 11 sessions.

Structure

The dataset is organised into two top-level dialect subsets:

Tupuri-Bango subset — 700 MP3 audio clips read by 6 native speakers of the Bango dialect, with a total duration of 2,442 seconds (00h 40m 42s), distributed across 7 recording sessions (one speaker contributed two sessions):

• Session tui-bango_02: 100 clips (07m 12s)

• Session tui-bango_03: 100 clips (07m 03s)

• Session tui-bango_03-1: 100 clips (04m 32s)

• Session tui-bango_05: 100 clips (05m 03s)

• Session tui-bango_06: 100 clips (05m 25s)

• Session tui-bango_07: 100 clips (05m 18s)

• Session tui-bango_08: 100 clips (06m 06s)

Tupuri-Banwere subset — 1,100 MP3 audio clips read by 10 native speakers of the Banwere dialect, with a total duration of 6,188 seconds (01h 43m 08s), distributed across 11 recording sessions (one speaker contributed two sessions):

• Session tui-banwere_01: 100 clips (10m 11s)

• Session tui-banwere_02: 100 clips (09m 18s)

• Session tui-banwere_03: 100 clips (14m 43s)

• Session tui-banwere_04: 100 clips (14m 43s)

• Session tui-banwere_05: 100 clips (06m 22s)

• Session tui-banwere_06: 100 clips (05m 41s)

• Session tui-banwere_07: 100 clips (07m 24s)

• Session tui-banwere_08: 100 clips (04m 51s)

• Session tui-banwere_08-1: 100 clips (06m 03s)

• Session tui-banwere_09: 100 clips (18m 04s)

• Session tui-banwere_10: 100 clips (05m 44s)

Each session folder contains:

1. 100 MP3 audio clips

2. One per-session sentence-to-audio mapping file (mapping.tsv), 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

• #attempts: number of recording attempts before acceptance

Sample

Bango dialect:

Banwere dialect: