DLRG@DravidianLangTech 2026: Dual-Purpose Whisper Adaptation for Tamil Dialect Identification and Dialectal Speech Recognition
Gulisetty Abhinav, Tanisha Nanda, Ramesh Kannan R, Ratnavel Rajalakshmi
Abstract
This paper describes our system developed for the shared task on Dialect Based Speech Recognition and Classification in Tamil at DravidianLangTech@ACL 2026. We participated in both Subtask 1 (Dialect Identification) and Subtask 2 (Dialectal ASR). Our approach leverages a single Tamil-adapted Whisper Medium model as a unified foundation for both tasks. For dialect classification, we have used the Whisper encoder as a feature extractor by discarding the decoder, applying mean pooling over the temporal dimension, and fine-tuning the full encoder with a lightweight classification head, achieving 73.4% accuracy on the test set. For dialectal ASR, we apply Low-Rank Adaptation (LoRA) to the full encoder-decoder architecture with SpecAugment-based data augmentation, achieving a Word Error Rate (WER) of 0.55 on the test set. Our experiments reveal that unfreezing the pre-trained encoder is critical for dialect discrimination, boosting accuracy from 52.78% (frozen) to 73.4% (unfrozen). The code is publicly available at https://github.com/DLRG-VIT/DravidianLangTech2026- Anthology ID:
- 2026.dravidianlangtech-1.33
- Volume:
- Proceedings of the Sixth Workshop on Speech, Vision, and Language Technologies for Dravidian Languages
- Month:
- July
- Year:
- 2026
- Address:
- Underline (Virtual)
- Editors:
- Bharathi Raja Chakravarthi, Ruba Priyadharshini, Anand Kumar Madasamy, Sajeetha Thavareesan, Saranya Rajiakodi, Subalalitha Navaneethakrishnan, Dhivya Chinnappa, Balasubramanian Palani, Malliga Subramanian, Kogilavani Shanmugavadivel, Ratnavel Rajalakshmi
- Venues:
- DravidianLangTech | WS
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 232–236
- Language:
- URL:
- https://preview.aclanthology.org/ingest-acl-workshops/2026.dravidianlangtech-1.33/
- DOI:
- Cite (ACL):
- Gulisetty Abhinav, Tanisha Nanda, Ramesh Kannan R, and Ratnavel Rajalakshmi. 2026. DLRG@DravidianLangTech 2026: Dual-Purpose Whisper Adaptation for Tamil Dialect Identification and Dialectal Speech Recognition. In Proceedings of the Sixth Workshop on Speech, Vision, and Language Technologies for Dravidian Languages, pages 232–236, Underline (Virtual). Association for Computational Linguistics.
- Cite (Informal):
- DLRG@DravidianLangTech 2026: Dual-Purpose Whisper Adaptation for Tamil Dialect Identification and Dialectal Speech Recognition (Abhinav et al., DravidianLangTech 2026)
- PDF:
- https://preview.aclanthology.org/ingest-acl-workshops/2026.dravidianlangtech-1.33.pdf