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high-resolution piano transcription system: detects piano notes from audio
957 runs


This model runs predictions on Nvidia T4 GPU hardware.

80% of predictions complete within 4 minutes. The predict time for this model varies significantly based on the inputs.


Piano transcription

Piano transcription is the task of transcribing piano recordings into MIDI files. This repo is the PyTorch implementation of our proposed high-resolution piano transcription system [1].


Here is a demo of our piano transcription system:


This codebase is developed with Python 3.7 and PyTorch 1.4.0 (Should work with other versions, but not fully tested).

Install dependencies:

pip install -r requirements.txt

Piano transcription using pretrained model

The easiest way is to transcribe a new piano recording is to install the piano_transcription_inference package: with pip as follows:

pip install piano_transcription_inference

Then, execute the following commands to transcribe this audio.

from piano_transcription_inference import PianoTranscription, sample_rate, load_audio

# Load audio
(audio, _) = load_audio('resources/cut_liszt.mp3', sr=sample_rate, mono=True)

# Transcriptor
transcriptor = PianoTranscription(device='cuda')    # 'cuda' | 'cpu'

# Transcribe and write out to MIDI file
transcribed_dict = transcriptor.transcribe(audio, 'cut_liszt.mid')

Train a piano transcription system from scratch

This section provides instructions if users would like to train a piano transcription system from scratch.

0. Prepare data

We use MAESTRO dataset V2.0.0 [1] to train the piano transcription system. MAESTRO consists of over 200 hours of virtuosic piano performances captured with fine alignment (~3 ms) between note labels and audio waveforms. MAESTRO dataset can be downloaded from

Statistics of MAESTRO V2.0.0 [ref]:

Split Performances Duration (hours) Size (GB) Notes (millions)
Train 967 161.3 97.7 5.73
Validation 137 19.4 11.8 0.64
Test 178 20.5 12.4 0.76
Total 1282 201.2 121.8 7.13

After downloading, the dataset looks like:

├── 2004
│    └── (264 files)
├── 2006
│    └── (230 files)
├── 2008
│    └── (294 files)
├── 2009
│    └── (250 files) 
├── 2011
│    └── (326 files)
├── 2013
│    └── (254 files)
├── 2014
│    └── (210 files)
├── 2015
│    └── (258 files)
├── 2017
│    └── (280 files)
├── 2018
│    └── (198 files)
├── maestro-v2.0.0.csv
├── maestro-v2.0.0.json

1. Train

Execute the commands line by line in, including:

1) Config dataset path and your workspace.
2) Pack audio recordings to hdf5 files.
3) Train piano note transcription system.
4) Train piano pedal transcription system.
5) Combine piano note and piano pedal transcription systems.
6) Evaluate.

All training steps are described in It worth looking into to see how the piano transcription system is trained. In total 29 GB GPU memoroy is required with a batch size of 12. Users may consider to reduce the batch size, or use multiple GPU cards to train this system.


The training uses a single Tesla-V100-PCIE-32GB card. The system is trained for 300k iterations for one week. The training looks like:

Namespace(augmentation='none', batch_size=12, cuda=True, early_stop=300000, filename='main', learning_rate=0.0005, loss_type='regress_onset_offset_frame_velocity_bce', max_note_shift=0, mini_data=False, mode='train', model_type='Regress_onset_offset_frame_velocity_CRNN', reduce_iteration=10000, resume_iteration=0, workspace='.../workspaces/piano_transcription')
Using GPU.
train segments: 571589
Evaluate train segments: 571589
Evaluate validation segments: 68646
Evaluate test segments: 71959
Iteration: 0
    Train statistics: {'frame_ap': 0.0613, 'reg_onset_mae': 0.514, 'reg_offset_mae': 0.482, 'velocity_mae': 0.1362}
    Validation statistics: {'frame_ap': 0.0605, 'reg_onset_mae': 0.5143, 'reg_offset_mae': 0.4819, 'velocity_mae': 0.133}
    Test statistics: {'frame_ap': 0.0601, 'reg_onset_mae': 0.5139, 'reg_offset_mae': 0.4821, 'velocity_mae': 0.1283}
    Dump statistics to .../workspaces/piano_transcription/statistics/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/statistics.pkl
    Dump statistics to .../workspaces/piano_transcription/statistics/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/statistics_2020-04-28_00-22-33.pickle
Train time: 5.498 s, validate time: 92.863 s
Model saved to .../workspaces/piano_transcription/checkpoints/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/0_iterations.pth
Iteration: 300000
    Train statistics: {'frame_ap': 0.9439, 'reg_onset_mae': 0.091, 'reg_offset_mae': 0.127, 'velocity_mae': 0.0241}
    Validation statistics: {'frame_ap': 0.9245, 'reg_onset_mae': 0.0985, 'reg_offset_mae': 0.1327, 'velocity_mae': 0.0265}
    Test statistics: {'frame_ap': 0.9285, 'reg_onset_mae': 0.097, 'reg_offset_mae': 0.1353, 'velocity_mae': 0.027}
    Dump statistics to .../workspaces/piano_transcription/statistics/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/statistics.pkl
    Dump statistics to .../workspaces/piano_transcription/statistics/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/statistics_2020-04-28_00-22-33.pickle
Train time: 8953.815 s, validate time: 93.683 s
Model saved to .../workspaces/piano_transcription/checkpoints/main/Regress_onset_offset_frame_velocity_CRNN/loss_type=regress_onset_offset_frame_velocity_bce/augmentation=none/batch_size=12/300000_iterations.pth

Visualization of piano transcription

Demo 1. Lang Lang: Franz Liszt - Love Dream (Liebestraum) [audio] [transcribed_midi]

Demo 2. Andras Schiff: J.S.Bach - French Suites [audio] [transcribed_midi]


If users met running out of GPU memory error, then try to reduce batch size.


Apache 2.0


We have built a large-scale classical piano MIDI dataset using our piano transcription system. See for details.


Qiuqiang Kong,


[1] Qiuqiang Kong, Bochen Li, Xuchen Song, Yuan Wan, and Yuxuan Wang. "High-resolution Piano Transcription with Pedals by Regressing Onsets and Offsets Times." arXiv preprint arXiv:2010.01815 (2020). [pdf]