The LoS Whisper-large-v3 model is a multilingual automatic speech recognition (ASR) system designed to transcribe punctuated speech in Spanish, Catalan, Galician, and Euskera (LoS, Languages of Spain). It is the result of fine-tuning the model openai/whisper-large-v3 on a combination of public and institutional datasets.

The model was trained on meticulously on 8,110 hours of preprocessed data. This ensures high-quality, readable transcriptions while preserving linguistic consistency. The training hours were equalized across the four languages to ensure comparable performance. Speed Perturbation (0.9× and 1.1×) was applied to every Basque training audio file, with a total duration of 2027h 56m 11s, which then served as the reference for balancing the remaining languages.

Intended Uses and Limitations

This model can be used for automatic speech recognition in the four languages mentioned.

Limitations: Speakers’ demographic information is not available; biases may exist due to institutional content.

How to Get Started with the Model

To see a functional version of this code, please check our Notebook and, in order to invoke this model, just substitute the instances of "projecte-aina/whisper-large-v3-ca-3catparla" with "BSC-LT/whisper-large-v3-LoS-punctuated".

Installation

To use this model, you may install datasets and transformers:

Create a virtual environment:

python -m venv /path/to/venv

Activate the environment:

source /path/to/venv/bin/activate

Install the modules:

pip install datasets transformers

For Inference

To transcribe an audio using this model, you can follow this example:

bash

#Install Prerequisites
pip install torch
pip install datasets
pip install 'transformers[torch]'
pip install evaluate
pip install jiwer

python

#This code works with a GPU

#Notice that: load_metric is no longer part of datasets.
# You have to remove it and use evaluate's load instead.
#(Note from November 2024)

import torch
from transformers import WhisperForConditionalGeneration, WhisperProcessor

#Load the processor and model.
MODEL_NAME="BSC-LT/whisper-large-v3-LoS-punctuated"
processor = WhisperProcessor.from_pretrained(MODEL_NAME)
model = WhisperForConditionalGeneration.from_pretrained(MODEL_NAME).to("cuda")

#Load the dataset
from datasets import load_dataset, load_metric, Audio
ds=load_dataset("projecte-aina/parlament_parla",split='test')

#Downsample to 16kHz
ds = ds.cast_column("audio", Audio(sampling_rate=16_000))

#Process the dataset
def map_to_pred(batch):
	audio = batch["audio"]
	input_features = processor(audio["array"], sampling_rate=audio["sampling_rate"], return_tensors="pt").input_features
	batch["reference"] = processor.tokenizer._normalize(batch['normalized_text'])

	with torch.no_grad():
		predicted_ids = model.generate(input_features.to("cuda"))[0]
	
	transcription = processor.decode(predicted_ids)
	batch["prediction"] = processor.tokenizer._normalize(transcription)
	
	return batch
	
#Do the evaluation
result = ds.map(map_to_pred)

#Compute the overall WER now.
from evaluate import load

wer = load("wer")
WER=100 * wer.compute(references=result["reference"], predictions=result["prediction"])
print(WER)

Training Details

Training data

The specific datasets used to create the model are: In Catalan:

"3CatParla" (To be published soon)
Parlament-Parla-v3 (Only the anonymized version of the dataset is public. We trained the model with the non-anonymized version)
Corts Valencianes (Only the anonymized version of the dataset is public. We trained the model with the non-anonymized version)
IB3 (To be published soon)
Common Voice ca 17 Benchmark

In Spanish:

In Galician:

In Euskera:

composite_corpus_eu_v2.1

Training procedure

This model is the result of finetuning the model "openai/whisper-large-v3" by following this tutorial provided by Hugging Face.

Training Hyperparameters

languages: Catalan, Spanish, Basque, Galician
hours of training audio: 8110h 28m
learning rate: 1e-5
sample rate: 16000 Hz
train batch size: 32 (×4 GPUs)
gradient accumulation: 1
eval batch size: 32
max steps: 172,294
warmup steps: 17,229
eval steps: 17,229
save steps: 17,229

Citation

If this model contributes to your research, please cite the work:

bibtex

@misc{LoS_Whisper2025,
      title={Acoustic Model in Catalan: whisper-large-v3-LoS-punctuated.}, 
      author={Hernandez Mena, Carlos Daniel; Abir Messaoudi; Sarah Solito; Cristina España-Bonet},
      organization={Barcelona Supercomputing Center},
      url={https://huggingface.co/BSC-LT/whisper-large-v3-LoS-punctuated},
      year={2025}
}

Additional Information

Author

The fine-tuning process was performed during November (2025) in the Language Technologies Laboratory of the Barcelona Supercomputing Center.

Contact

For further information, please send an email to langtech@bsc.es.

Copyright

License

Apache-2.0

Funding

This work is funded by the Ministerio para la Transformación Digital y de la Función Pública - Funded by EU – NextGenerationEU within the framework of the project ILENIA with reference 2022/TL22/00215337. The training of the model was possible thanks to the computing time provided by Barcelona Supercomputing Center through MareNostrum 5.

BSC-LT/whisper-large-v3-LoS-punctuated

whisper-large-v3-LoS-punctuated

Table of Contents

Model Description