Stop extracting features when hubert_base.pt does not exist. (#535)

* support detection of pretrained model, support train without pretrained model path in web ui

* support detection of pretrained model, support train without pretrained model path in web ui

* support detection of pretrained model, support train without pretrained model path in web ui

* Stop extracting features when hubert_base.pt is not exist.

* Stop extracting features when hubert_base.pt is not exist.

* Make error more noticeable

Author: JunityZhan

extract_feature_print.py

@@ -63,6 +63,10 @@ def readwave(wav_path, normalize=False):
 
 # HuBERT model
 printt("load model(s) from {}".format(model_path))
+# if hubert model is exist
+if (os.access(model_path, os.F_OK) == False):
+    printt("Error: Extracting is shut down because %s does not exist, you may download it from https://huggingface.co/lj1995/VoiceConversionWebUI/tree/main" % model_path)
+    exit(0)
 models, saved_cfg, task = checkpoint_utils.load_model_ensemble_and_task(
     [model_path],
     suffix="",