Continaul Self-Supervised Learning (CSSL) for Sound Classification

This is the code base for the paper "Learning Representations for New Sound Classes With Continual Self-Supervised Learning". This paper is accepted by the IEEE Signal Processing Letters.

Requirements

pytorch == 1.10.0
torchaudio == 0.10.0
tqdm == 4.62.3
speechbrain == 0.5.11
torchlibrosa == 0.0.9
torchmetrics == 0.5.1

Experiments

UrbanSound8K

We produce the scripts for reproducing the supervised and self-supervised experiments for the class-incremental representation learning. The following command will run the encoder training using the simclr objective on the UrbanSound8K dataset:

python supclr_train.py hparams/us8k/supclr_train.yaml --output_base <ENCODER_OUTPUT_DIR> --replay_num_keep=0 --use_mixup=False --ssl_weight=1 --sup_weight=0 --train_duration=2.0 --emb_norm_type=bn --proj_norm_type=bn --batch_size=32 --experiment_name=<NAME>

And all configurations can be modified at ./hparams/us8k/supclr_train.yaml. Make sure to configure the path to the datasets properly. After the encoder is trained, use the linear evaluation script to measure the performance of the learned representations:

python linclf_train.py hparams/us8k/linclf_train.yaml --output_base <EVAL_OUTPUT_DIR> --linclf_train_type=seen --replay_num_keep=all --ssl_checkpoints_dir=<PATH_TO_ENCODER_CKPT> --emb_norm_type bn --experiment_name=<NAME>

Here, the <PATH_TO_ENCODER_CKPT> should be identical to the <ENCODER_OUTPUT_DIR> with a /save suffix. The script will look for the task-wise encoder checkpoint under this directory when evaluating on each task. The linclf_train_type is set as seen, which will perform linear evaluation protocol (LEP). It can be assigned a value of subset, which will instead perform subset linear evaluation protocol (SLEP).

DCASE TAU19

For encoder training, run

python supclr_train.py hparams/tau19/supclr_train.yaml --output_base <ENCODER_OUTPUT_DIR> --replay_num_keep=0 --use_mixup=False --ssl_weight=1 --sup_weight=0 --train_duration=4.0 --emb_norm_type bn --proj_norm_type bn --batch_size=32 --experiment_name=<NAME>

For in-domain linear evaluation, run

python linclf_train.py hparams/tau19/linclf_train.yaml --output_base <EVAL_OUTPUT_DIR> --linclf_train_type=seen --ssl_checkpoints_dir=<PATH_TO_ENCODER_CKPT> --emb_norm_type bn --experiment_name=<NAME>

VGGSound

For encoder training, run

python supclr_train.py hparams/vgg/supclr_train.yaml --output_base <ENCODER_OUTPUT_DIR> --replay_num_keep=0 --use_mixup=False --ssl_weight=1 --sup_weight=0 --train_duration=4.0 --emb_norm_type bn --proj_norm_type bn --batch_size=32 --experiment_name=<NAME>

(Deprecated) Sample Commands

The following section may be outdated, and please refer to the Experiments section.

Supervised Training

To run the supervised class-incremental experiment, run

python sup_train.py hparams/sup_train.yaml --data_folder <YOUR_DATA_FOLDER> --output_base <YOUR_OUTPUT_FOLDER>

To run the supervised offline training (full dataset at once), replace the arguments of task_classes in hparams/sup_train.yaml with

task_classes:
    - !tuple (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)

before running the training script.

You may want to checkout the following configurations in the hyperparameter yaml file to configure the experiments:

replay_num_keep: size of the replay buffer for each task
use_mixup: flag of using mixup as a data augmentation
training_folds, valid_folds, test_folds: urbansound8k fold index for training, validation and test
embedding_model: encoder/backbone model, currently support the TDNN and PANN architectures

SimSiam Training

Similar to the settings in the supervised training, to run experiments with SimSiam as a self-supervised method, run

python simsiam_train.py hparams/simsiam_train.yaml --data_folder <YOUR_DATA_FOLDER> --output_base <YOUR_OUTPUT_FOLDER>

SimCLR Training

Similar to the settings in the supervised and SimSiam training, to run experiments with SimCLR as a self-supervised method, run

python simclr_train.py hparams/simclr_train.yaml --data_folder <YOUR_DATA_FOLDER> --output_base <YOUR_OUTPUT_FOLDER>

Linear Evaluation

To run the linear classification on top of the frozen pretrained models, run

python linclf_train.py hparams/linclf_train.yaml --linclf_train_type buffer --data_folder <YOUR_DATA_FOLDER> --output_base <YOUR_OUTPUT_FOLDER> --ssl_checkpoints_dir <YOUR_SSL_FOLDER>

Make sure the YOUR_SSL_FOLDER ends with the save directory, as the file will redirect under the save directory to look for the proper checkpoint for each individual task.

We follow the paradigms in the Co2L, we implement three scenarios for training the linear classifier. By default, we train the linear classifier with all data from the current task along with the replay buffer from previous tasks with the --linclf_train_type buffer flag (class-balanced sampling still WIP).

To investigate the tendency for catastrophic forgetting on the algorithms, we pick the embeddings learned without any handling of continual learning (no buffer, finetuning with data only from the current task). Then, we train the linear classifier with the flag --linclf_train_type seen, which trains the linear classifier with all data samples from the first to the current task (equivalent to a full buffer).

To evaluate whether the representation learned is useful for future tasks, we train the classifier with the flag --linclf_train_tyep full, which trains the classifier with data samples from all tasks on top of the embedder at each task.

Visualization

We provide a notebook for visualizing the learned embeddings for continually trained embedding models. Please configure the following in hparams/visualize.yaml:

csv_path: this is for loading the training and test data, and we recommend loading the offline dataset with all tasks
ssl_checkpoints_dir: same as in linear evaluation

fpaissan/cssl_sound