using librosa to load the audio file

src/separation/demucs_wrapper.py

@@ -1,5 +1,30 @@
 import subprocess
 import os
+import librosa
+import soundfile as sf
+import tempfile
+
+def preprocess_audio(input_file: str, target_sr: int = 41000):
+    """
+    Preprocess the audio file by loading, converting to mono, and resampling.
+
+    Parameters:
+        input_file (str): Path to the input audio file to be processed.
+        target_sr (int): The target sample rate for the resampled audio.
+
+    Returns:
+        str: Path to the temporary processed audio file.
+    """
+    # Load the audio with librosa, converting to mono and resampling
+    waveform, sr = librosa.load(input_file, sr=target_sr, mono=True)
+    
+    # Create a temporary file to save the processed audio
+    temp_audio_path = tempfile.mktemp(suffix=".wav")
+    
+    # Save the processed audio to the temporary file
+    sf.write(temp_audio_path, waveform, target_sr)
+    
+    return temp_audio_path
 
 def separate_audio_with_demucs(input_file: str, output_dir: str = './separated_output'):
     """
@@ -12,12 +37,14 @@ def separate_audio_with_demucs(input_file: str, output_dir: str = './separated_o
     # Create the output directory if it does not exist
     os.makedirs(output_dir, exist_ok=True)
 
+    # Preprocess the audio file
+    processed_audio = preprocess_audio(input_file)
+
     # Demucs command to separate the audio file
-    # --out: specifies output directory
     command = [
         'demucs',
         '--out', output_dir,  # Output directory for separated tracks
-        input_file            # Input file
+        processed_audio       # Input processed file
     ]
     
     try:
@@ -28,6 +55,9 @@ def separate_audio_with_demucs(input_file: str, output_dir: str = './separated_o
         print(f"An error occurred while running Demucs: {e}")
     except FileNotFoundError:
         print("Demucs is not installed or not found in the system PATH.")
+    finally:
+        # Clean up the temporary file
+        os.remove(processed_audio)
 
 if __name__ == "__main__":
     # Example usage