---
title: DExter
emoji: 🎹
colorFrom: purple
colorTo: indigo
sdk: gradio
sdk_version: 6.24.0
python_version: '3.10'
app_file: app.py
pinned: false
license: mit
short_description: Render expressive piano performance from a score
tags:
  - category:synthesis
  - subcategory:performance-rendering
  - input:file/xml|musicxml
  - output:midi
  - piano
startup_duration_timeout: 1h
---

# DExter

HARP endpoint for expressive piano performance rendering. Upload a MusicXML piano score, or use the bundled Schubert example, and download a generated MIDI performance. The model uses the official score-only pretrained checkpoint. Perceptual feature controls and style transfer are not available in the official custom-score inference path.

The upstream source code is MIT licensed. The separately hosted checkpoint has no stated redistribution license, so the Space is marked with an unknown overall license; see [SOURCES.md](SOURCES.md).

## Local setup

```bash
uv venv --python 3.10 .venv
UV_CACHE_DIR=/path/to/writable/cache uv pip install --python .venv/bin/python -r requirements.txt
git lfs pull
.venv/bin/python app.py
```

Run direct inference with `from runtime import render; render("score.musicxml", "performance.mid")`. The official sampler uses 999 diffusion steps and can be slow on CPU. Source, checkpoint provenance, and redistribution note are in [SOURCES.md](SOURCES.md).