Update README.md

## Guidelines for Converting Piper ONNX Model

**References:**
* https://github.com/nihui/ncnn-android-piper
* https://github.com/OHF-Voice/piper1-gpl
* https://huggingface.co/datasets/rhasspy/piper-checkpoints

**Steps to convert Piper checkpoints to NCNN models:**

1. **Checkout the correct version of the piper repository:**
```bash
git clone [https://github.com/OHF-Voice/piper1-gpl](https://github.com/OHF-Voice/piper1-gpl)
cd piper1-gpl
git checkout 113931937cf235fc8all1afd1ca4be209bc6919bc7
```

2. **Apply the necessary patch:**
```bash
# Ensure 'piper1-gpl.patch' is available
git apply piper1-gpl.patch
```

3. **Set up the Python environment and install dependencies:**
```bash
python3 -m venv .venv
source .venv/bin/activate
python3 -m pip install -e .[train]
```

4. **Download a Piper checkpoint file (`.ckpt`) from Hugging Face:**
https://huggingface.co/datasets/rhasspy/piper-checkpoints

5. **Install the PNNX model converter:**
```bash
pip install -U pnnx
```

6. **Obtain the `export_ncnn.py` script.**

7. **Run the conversion script on your checkpoint file:**
```bash
# Replace with your actual file
python export_ncnn.py (language code).ckpt (e.g., en.ckpt, fa.ckpt, ...)
```

README.md

@@ -1,3 +1,26 @@
----
-license: mit
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+---
+license: mit
+language:
+- en
+- id
+- hi
+- fr
+- ar
+- ne
+- 'no'
+- sw
+- sr
+- zh
+- vi
+- tr
+- uk
+- ru
+- ro
+- pt
+- pl
+- nl
+- hu
+- fa
+- es
+- cs
+---