Update app.py

app.py

@@ -21,6 +21,7 @@ matplotlib.use('Agg') # Use a non-interactive backend for plotting
 # --- Helper/Processing Functions ---
 
 def update_output_visibility(choice):
+    # This function remains the same
     if "2 Stems" in choice:
         return { 
             vocals_output: gr.update(visible=True), 
@@ -36,35 +37,8 @@ def update_output_visibility(choice):
             other_output: gr.update(visible=True, label="Other") 
         }
 
-# --- NEW, CORRECTED BAR DETECTION FUNCTION ---
-def detect_bars(audio_file_path):
-    if audio_file_path is None or not os.path.exists(audio_file_path):
-        return None, None, None
-
-    try:
-        # 1. Load the audio file inside the function
-        y, sr = librosa.load(audio_file_path, sr=None)
-        
-        # 2. Convert to mono for analysis
-        y_mono = librosa.to_mono(y) if y.ndim > 1 else y
-        
-        # 3. Perform beat and tempo analysis
-        tempo, beats = librosa.beat.beat_track(y=y_mono, sr=sr)
-        
-        bpm = 120 if tempo is None else int(np.round(tempo).item())
-        beat_times = librosa.frames_to_time(beats, sr=sr)
-        
-        # This is a simple way to estimate bar start times (assuming 4/4 time)
-        bar_times = beat_times[::4] 
-        
-        return bpm, beat_times, bar_times
-        
-    except Exception as e:
-        print(f"Error in detect_bars: {e}")
-        return None, None, None
-
-
 async def separate_stems(audio_file_path, stem_choice, progress=gr.Progress(track_tqdm=True)):
+    # This function now returns to both the visible UI and the hidden state
     if audio_file_path is None: raise gr.Error("No audio file uploaded!")
     progress(0, desc="Starting...")
     try:
@@ -78,25 +52,17 @@ async def separate_stems(audio_file_path, stem_choice, progress=gr.Progress(trac
         if os.path.exists(output_dir): shutil.rmtree(output_dir)
         
         command = f"python3 -m demucs {model_arg} -o \"{output_dir}\" \"{stable_input_path}\""
-        progress(0.2, desc="Running Demucs (this may take a minute)...")
-        
-        process = await asyncio.create_subprocess_shell(
-            command,
-            stdout=asyncio.subprocess.PIPE,
-            stderr=asyncio.subprocess.PIPE)
-        
+        progress(0.2, desc="Running Demucs..."); 
+        process = await asyncio.create_subprocess_shell(command, stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.PIPE)
         await process.communicate()
-
-        if process.returncode != 0: 
-            raise gr.Error(f"Demucs failed to run. Error")
+        if process.returncode != 0: raise gr.Error(f"Demucs failed to run.")
 
         progress(0.8, desc="Locating separated stem files...")
         stable_filename_base = os.path.basename(stable_input_path).rsplit('.', 1)[0]
         model_folder_name = next(os.walk(output_dir))[1][0]
         stems_path = os.path.join(output_dir, model_folder_name, stable_filename_base)
         
-        if not os.path.exists(stems_path): 
-            raise gr.Error(f"Demucs finished, but the output directory was not found!")
+        if not os.path.exists(stems_path): raise gr.Error(f"Demucs finished, but the output directory was not found!")
             
         vocals_path = os.path.join(stems_path, "vocals.wav") if os.path.exists(os.path.join(stems_path, "vocals.wav")) else None
         drums_path = os.path.join(stems_path, "drums.wav") if os.path.exists(os.path.join(stems_path, "drums.wav")) else None
@@ -105,45 +71,26 @@ async def separate_stems(audio_file_path, stem_choice, progress=gr.Progress(trac
         other_path = os.path.join(stems_path, other_filename) if os.path.exists(os.path.join(stems_path, other_filename)) else None
         
         os.remove(stable_input_path)
-
-        # --- CALLING THE NEW BAR DETECTION FUNCTION ---
-        progress(0.9, desc="Analyzing stem structure...")
-        all_paths = {"vocals": vocals_path, "drums": drums_path, "bass": bass_path, "other": other_path}
-        for name, path in all_paths.items():
-            if path:
-                bpm, _, bar_times = detect_bars(path)
-                if bpm and bar_times is not None:
-                    print(f"--- Analysis for {name} ---")
-                    print(f"Detected BPM: {bpm}")
-                    print(f"Found {len(bar_times)} bars.")
-        
-        return vocals_path, drums_path, bass_path, other_path
+        # Return values for the visible UI and the hidden state variables
+        return vocals_path, drums_path, bass_path, other_path, vocals_path, drums_path, bass_path, other_path
     except Exception as e:
-        print(f"An error occurred: {e}")
-        raise gr.Error(str(e))
-
-# This is the placeholder for the interactive editor we were building
-def preview_slice(active_stem_audio, onset_times, evt: gr.SelectData):
-    if active_stem_audio is None or onset_times is None: return None
-    sample_rate, y = active_stem_audio; clicked_time = evt.index[0]
-    start_time = 0; end_time = len(y) / sample_rate
-    for i, t in enumerate(onset_times):
-        if t > clicked_time:
-            end_time = t; break
-        start_time = t
-    start_sample = librosa.time_to_samples(start_time, sr=sample_rate)
-    end_sample = librosa.time_to_samples(end_time, sr=sample_rate)
-    sliced_audio = y[start_sample:end_sample]
-    return (sample_rate, sliced_audio)
+        print(f"An error occurred: {e}"); raise gr.Error(str(e))
 
+# --- NEW FUNCTION TO REPOPULATE UI ON PAGE LOAD ---
+def repopulate_ui_from_state(vocals_path, drums_path, bass_path, other_path):
+    # This function takes the saved paths from the state and updates the audio players
+    print("Page reloaded. Repopulating UI from session state.")
+    return vocals_path, drums_path, bass_path, other_path
 
 # --- Create the full Gradio Interface ---
 with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red")) as demo:
     gr.Markdown("# 🎵 Loop Architect")
     
-    # State components
-    onset_times_state = gr.State(value=None)
-    active_stem_state = gr.State(value=None)
+    # --- NEW STATE COMPONENTS FOR PERSISTENCE ---
+    vocals_path_state = gr.State(None)
+    drums_path_state = gr.State(None)
+    bass_path_state = gr.State(None)
+    other_path_state = gr.State(None)
     
     with gr.Row():
         with gr.Column(scale=1):
@@ -164,8 +111,25 @@ with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red"))
                     other_output = gr.Audio(label="Other / Instrumental", scale=4)
 
     # --- Define Event Listeners ---
-    submit_button.click(fn=separate_stems, inputs=[audio_input, stem_options], outputs=[vocals_output, drums_output, bass_output, other_output])
+    
+    # The submit button now updates both the visible audio players AND the hidden state variables
+    submit_button.click(
+        fn=separate_stems, 
+        inputs=[audio_input, stem_options], 
+        outputs=[
+            vocals_output, drums_output, bass_output, other_output, 
+            vocals_path_state, drums_path_state, bass_path_state, other_path_state
+        ]
+    )
+    
     stem_options.change(fn=update_output_visibility, inputs=stem_options, outputs=[vocals_output, drums_output, bass_output, other_output])
+
+    # --- NEW EVENT LISTENER FOR PAGE LOAD ---
+    demo.load(
+        fn=repopulate_ui_from_state,
+        inputs=[vocals_path_state, drums_path_state, bass_path_state, other_path_state],
+        outputs=[vocals_output, drums_output, bass_output, other_output]
+    )
     
 # --- Launch the UI ---
 demo.launch()