egs/tta/RECIPE.md

Text-to-Audio with Latent Diffusion Model

This is the quicktour for training a text-to-audio model with the popular and powerful generative model: Latent Diffusion Model. Specially, this recipe is also the official implementation of the text-to-audio generation part of our NeurIPS 2023 paper "AUDIT: Audio Editing by Following Instructions with Latent Diffusion Models". You can check the last part of AUDIT demos to see same text-to-audio examples.

We train this latent diffusion model in two stages:

1. In the first stage, we aims to obtain a high-quality VAE (called AutoencoderKL in Amphion), in order that we can project the input mel-spectrograms to an efficient, low-dimensional latent space. Specially, we train the VAE with GAN loss to improve the reconstruction quality.
2. In the second stage, we aims to obtain a text-controllable diffusion model (called AudioLDM in Amphion). We use U-Net architecture diffusion model, and use T5 encoder as text encoder.

There are four stages in total for training the text-to-audio model:

1. Data preparation and processing
2. Train the VAE model
3. Train the latent diffusion model
4. Inference

NOTE: You need to run every command of this recipe in the Amphion root path:

cd Amphion

Overview

# Train the VAE model
sh egs/tta/autoencoderkl/run_train.sh

# Train the latent diffusion model
sh egs/tta/audioldm/run_train.sh

# Inference
sh egs/tta/audioldm/run_inference.sh

1. Data preparation and processing

Dataset Download

We take AudioCaps as an example, AudioCaps is a dataset of around 44K audio-caption pairs, where each audio clip corresponds to a caption with rich semantic information. We have already processed the dataset. You can download the dataset here.

Data Processing

• Download AudioCaps dataset to [Your path to save tta dataset] and modify preprocess.processed_dir in egs/tta/.../exp_config.json.

{
  "dataset": [
    "AudioCaps"
  ],
  "preprocess": {
    // Specify the output root path to save the processed data 
    "processed_dir": "[Your path to save tta dataset]",
    ...
  }
}

The folder structure of your downloaded data should be similar to:

.../[Your path to save tta dataset]
┣ AudioCaps
┃   ┣ wav
┃   ┃   ┣ ---1_cCGK4M_0_10000.wav
┃   ┃   ┣ ---lTs1dxhU_30000_40000.wav
┃   ┃   ┣ ...

• Then you may process the data to mel-specgram and save it as .npy format. If you use the data we provide, we have processed all the wav data.

• Generate a json file to save the metadata, the json file is like:

[
    {
        "Dataset": "AudioCaps",
        "Uid": "---1_cCGK4M_0_10000",
        "Caption": "Idling car, train blows horn and passes"
    },
    {
        "Dataset": "AudioCaps",
        "Uid": "---lTs1dxhU_30000_40000",
        "Caption": "A racing vehicle engine is heard passing by"
    },
    ...
]

• Finally, the folder structure is like:

.../[Your path to save tta dataset]
┣ AudioCpas
┃   ┣ wav
┃   ┃   ┣ ---1_cCGK4M_0_10000.wav
┃   ┃   ┣ ---lTs1dxhU_30000_40000.wav
┃   ┃   ┣ ...
┃   ┣ mel
┃   ┃   ┣ ---1_cCGK4M_0_10000.npy
┃   ┃   ┣ ---lTs1dxhU_30000_40000.npy
┃   ┃   ┣ ...
┃   ┣ train.json
┃   ┣ valid.json
┃   ┣ ...

2. Training the VAE Model

The first stage model is a VAE model trained with GAN loss (called AutoencoderKL in Amphion), run the follow commands:

sh egs/tta/autoencoderkl/run_train.sh

3. Training the Latent Diffusion Model

The second stage model is a condition diffusion model with a T5 text encoder (called AudioLDM in Amphion), run the following commands:

sh egs/tta/audioldm/run_train.sh

4. Inference

Now you can generate audio with your pre-trained latent diffusion model, run the following commands and modify the text argument.

sh egs/tta/audioldm/run_inference.sh \
--text "A man is whistling"

Citations

@article{wang2023audit,
  title={AUDIT: Audio Editing by Following Instructions with Latent Diffusion Models},
  author={Wang, Yuancheng and Ju, Zeqian and Tan, Xu and He, Lei and Wu, Zhizheng and Bian, Jiang and Zhao, Sheng},
  journal={NeurIPS 2023},
  year={2023}
}

@article{liu2023audioldm,
  title={{AudioLDM}: Text-to-Audio Generation with Latent Diffusion Models},
  author={Liu, Haohe and Chen, Zehua and Yuan, Yi and Mei, Xinhao and Liu, Xubo and Mandic, Danilo and Wang, Wenwu and Plumbley, Mark D},
  journal={Proceedings of the International Conference on Machine Learning},
  year={2023}
}