This Python library allows pre-training and fine-tuning contrastive embeddings of audio with the COLA method. In particular, one can:

• Pre-train COLA embeddings, which use a simple contrastive learning method
• Train a linear classifier on pre-trained embeddings
• Train a supervised neural network from scratch
• Initialize a classifier with pre-trained COLA embeddings and fine-tune on a new dataset

• TensorFlow
• TensorFlow Datasets

Training has three modes:

• SSL, to pre-train a model with self-supervised contrastive learning
• DS to fine-tune a pre-trained model on a downstream task
• SUP to train a simple supervised system

Pre-train a COLA embedding on a dataset from tensorflow_datasets (here, LibriSpeech):

python -m main --experiment_id=cola_pretrain --model_dir=/tmp/cola \
--training_mode=SSL --ssl_dataset=LBS --strategy=gpu

Note that so far labels are not necessary. After pre-training, the model is saved in /tmp/cola/librispeech/cola_pretrain.

One can train a linear classifier on these embeddings, on the Speech Commands dataset, in a supervised fashion:

python -m main --experiment_id=cola_downstream --ssl_checkpoint_id=cola_pretrain \
--model_dir=/tmp/cola --training_mode=DS --ssl_dataset=LBS --ds_dataset=SPCV2 \
--strategy=gpu --freeze_encoder=true

The flags --ssl_checkpoint_id and --ssl_dataset indicate that the pre-trained model is stored in /tmp/cola/librispeech/cola_pretrain.

Note the --freeze_encoder flag. If set to False, the entire network is fine-tuned.

Pre-training and fine-tuning only handle tfds datasets, for simplicity. One can easily use arbitrary datasets by overriding the get_self_supervised_data and get_downstream_dataset methods in data.py.

If you use this repository, please consider citing:

@misc{saeed2020contrastive,
      title={Contrastive Learning of General-Purpose Audio Representations},
      author={Aaqib Saeed and David Grangier and Neil Zeghidour},
      year={2020},
      eprint={2010.10915},
      archivePrefix={arXiv},
      primaryClass={cs.SD}
}