Update app.py

app.py

@@ -230,7 +230,16 @@ class VibeVoiceDemo:
             return None, error_msg
 
 
-
+    @staticmethod
+    def _infer_num_speakers_from_script(script: str) -> int:
+        """
+        Infer number of speakers by counting distinct 'Speaker X:' tags in the script.
+        Robust to 0- or 1-indexed labels and repeated turns.
+        Falls back to 1 if none found.
+        """
+        import re
+        ids = re.findall(r'(?mi)^\s*Speaker\s+(\d+)\s*:', script)
+        return len({int(x) for x in ids}) if ids else 1
 
     def load_example_scripts(self):
         examples_dir = os.path.join(os.path.dirname(__file__), "text_examples")