README.md

---
title: HybridGAN Speech Bandwidth Extension
emoji: 🎧
colorFrom: blue
colorTo: indigo
sdk: gradio
sdk_version: 5.9.0
app_file: app.py
pinned: false
license: mit
---

# 🎧 HybridGAN-BWE: Speech Bandwidth Extension & Telephony Restoration

Band-limited narrowband telecommunication signals (standard landline G.711 codecs, mobile GSM channels, handset microphone cut-offs) restrict speech bandwidth to 300 Hz – 3400 Hz or 0 Hz – 4000 Hz. This severely degrades voice naturalness, intelligibility, and speaker identification.

**HybridGAN-BWE** presents a real-time, parameter-efficient Speech Bandwidth Extension system that reconstructs high-fidelity wideband speech (**16 kHz**) from narrowband input (**8 kHz**).

---

## 🚀 Key Features

* **Dual-Path Spectral Encoder**: Combines 2D spatial spectrogram convolutions and 1D temporal frame features fused via Multi-Head Cross-Attention.
* **Domain Randomization**: Robust against real-world telephone noise, GSM/G.711 compression, and handset high-pass cut-offs.
* **Parameter Efficient**: Squeezed 2D Spectrogram Discriminators (channels reduced from 32 to 16, saving 67% discriminator parameters).
* **CPU Compatible**: Optimized for CPU inference on Hugging Face Free Tier Spaces.

---

## 📦 Hugging Face Space Repository Structure

```
.
├── app.py              # Main Gradio application entrypoint
├── README.md           # Space Metadata & Documentation
├── requirements.txt    # Minimal dependencies (PyTorch, Gradio, Librosa)
├── config.yaml         # Model configuration parameters
├── best_model.pth      # Lightweight Generator model checkpoint
├── models/             # Model generator and discriminator definitions
├── modules/            # Spectral branch, waveform branch, and attention modules
└── utils/              # Config loader utility
```

---

## 🛠️ Local Testing Guide

To test this space locally on your machine:

```bash
cd hf_space
pip install -r requirements.txt
python app.py
```
Open **[http://127.0.0.1:7860](http://127.0.0.1:7860)** in your browser.