---
license: mit
tags:
- audio tagging
- audio events
- audio embeddings
- convnext-audio
- audioset
---

**ConvNeXt-Tiny-AT** is an audio tagging CNN model, trained on **AudioSet** (balanced+unbalanced subsets). It reached 0.471 mAP on the test set.

The model expects as input audio files of duration 10 seconds, and sample rate 32kHz.
It provides logits and probabilities for the 527 audio event tags of AudioSet (see http://research.google.com/audioset/index.html).
Two methods can also be used to get scene embeddings (a single vector per file) and frame-level embeddings, see below.
The scene embedding is obtained from the frame-level embeddings, on which mean pooling is applied onto the frequency dim, followed by mean pooling + max pooling onto the time dim.

# Install

This code is based on our repo: https://github.com/topel/audioset-convnext-inf


```bash
pip install git+https://github.com/topel/audioset-convnext-inf@pip-install
```

# Usage

Below is an example of how to instantiate our model convnext_tiny_471mAP.pth

```python
import os
import numpy as np
import torch
import torchaudio

from audioset_convnext_inf.pytorch.convnext import ConvNeXt

model = ConvNeXt.from_pretrained("topel/ConvNeXt-Tiny-AT", use_auth_token=None, map_location='cpu', use_auth_token="ACCESS_TOKEN_GOES_HERE")

print(
    "# params:",
    sum(param.numel() for param in model.parameters() if param.requires_grad),
)
if torch.cuda.is_available():
    device = torch.device("cuda")
else:
    device = torch.device("cpu")

if "cuda" in str(device):
    model = model.to(device)
```

Output:
```
# params: 28222767
```

## Inference: get logits and probabilities

```python
sample_rate = 32000
audio_target_length = 10 * sample_rate  # 10 s

AUDIO_FNAME = "f62-S-v2swA_200000_210000.wav"
AUDIO_FPATH = os.path.join("/path/to/audio", AUDIO_FNAME)

waveform, sample_rate_ = torchaudio.load(AUDIO_FPATH)
if sample_rate_ != sample_rate:
    print("ERROR: sampling rate not 32k Hz", sample_rate_)

waveform = waveform.to(device)

print("\nInference on " + AUDIO_FNAME + "\n")

with torch.no_grad():
    model.eval()
    output = model(waveform)

logits = output["clipwise_logits"]
print("logits size:", logits.size())

probs = output["clipwise_output"]
# Equivalent: probs = torch.sigmoid(logits)
print("probs size:", probs.size())

threshold = 0.25
sample_labels = np.where(probs[0].clone().detach().cpu() > threshold)[0]
print("Predicted labels using activity threshold 0.25:\n")
print(sample_labels)
```

Output:
```
logits size: torch.Size([1, 527])
probs size: torch.Size([1, 527])
Predicted labels using activity threshold 0.25:

[  0 137 138 139 151 506]
```



## Get audio scene embeddings
```python
with torch.no_grad():
    model.eval()
    output = model.forward_scene_embeddings(waveform)

print("\nScene embedding, shape:", output.size())
```

Output:
```
Scene embedding, shape: torch.Size([1, 768])
```

## Get frame-level embeddings
```python
with torch.no_grad():
    model.eval()
    output = model.forward_frame_embeddings(waveform)

print("\nFrame-level embeddings, shape:", output.size())
```

Output:
```
Frame-level embeddings, shape: torch.Size([1, 768, 31, 7])
```

# Zenodo

The checkpoint is also available on Zenodo: https://zenodo.org/record/8020843/files/convnext_tiny_471mAP.pth?download=1

Together with a second checkpoint: convnext_tiny_465mAP_BL_AC_70kit.pth

The second model is useful to perform audio captioning on the AudioCaps dataset without training data biases. It was trained the same way as the current model, for audio tagging on AudioSet, but the files from AudioCaps were removed from the AudioSet development set.


# Citation

Cite as: Pellegrini, T., Khalfaoui-Hassani, I., Labbé, E., Masquelier, T. (2023) Adapting a ConvNeXt Model to Audio Classification on AudioSet. Proc. INTERSPEECH 2023, 4169-4173, doi: 10.21437/Interspeech.2023-1564

```bibtex
@inproceedings{pellegrini23_interspeech,
  author={Thomas Pellegrini and Ismail Khalfaoui-Hassani and Etienne Labb\'e and Timoth\'ee Masquelier},
  title={{Adapting a ConvNeXt Model to Audio Classification on AudioSet}},
  year=2023,
  booktitle={Proc. INTERSPEECH 2023},
  pages={4169--4173},
  doi={10.21437/Interspeech.2023-1564}
}
```