update README

README.md

@@ -110,6 +110,8 @@ bash inference_e2e.sh
 ### 🎤 SongFormBench-CN  
 Reproduce using [**bigvgan_v2_44khz_128band_256x**](https://huggingface.co/nvidia/bigvgan_v2_44khz_128band_256x)
 
+You should first download bigvgan_v2_44khz_128band_256x, then add its project directory to your PYTHONPATH, after which you can use the code below:
+
 ```python
 # See implementation
 utils/CN/infer.py

README_ZH.md

@@ -99,6 +99,7 @@ bash inference_e2e.sh
 ### 🎤 SongFormBench-CN  
 使用 [**bigvgan_v2_44khz_128band_256x**](https://huggingface.co/nvidia/bigvgan_v2_44khz_128band_256x) 重建。
 
+您应首先下载 bigvgan_v2_44khz_128band_256x，然后将其项目目录添加到 PYTHONPATH 中，之后即可使用以下代码：
 ```python
 # 查看实现
 utils/CN/infer.py