Update app.py

app.py

@@ -1,3 +1,6 @@
+# 1. Install all necessary libraries for the full application
+# This line is for Colab. On Hugging Face, these should be in your requirements.txt
+# !pip install gradio "demucs>=4.0.0" librosa soundfile matplotlib
 
 # 2. Import libraries
 import gradio as gr
@@ -19,65 +22,128 @@ matplotlib.use('Agg') # Use a non-interactive backend for plotting
 
 def update_output_visibility(choice):
     if "2 Stems" in choice:
-        return { vocals_output: gr.update(visible=True), drums_output: gr.update(visible=False), bass_output: gr.update(visible=False), other_output: gr.update(visible=True, label="Instrumental (No Vocals)") }
+        return { 
+            vocals_output: gr.update(visible=True), 
+            drums_output: gr.update(visible=False), 
+            bass_output: gr.update(visible=False), 
+            other_output: gr.update(visible=True, label="Instrumental (No Vocals)") 
+        }
     elif "4 Stems" in choice:
-        return { vocals_output: gr.update(visible=True), drums_output: gr.update(visible=True), bass_output: gr.update(visible=True), other_output: gr.update(visible=True, label="Other") }
+        return { 
+            vocals_output: gr.update(visible=True), 
+            drums_output: gr.update(visible=True), 
+            bass_output: gr.update(visible=True), 
+            other_output: gr.update(visible=True, label="Other") 
+        }
 
 async def separate_stems(audio_file_path, stem_choice, progress=gr.Progress(track_tqdm=True)):
     if audio_file_path is None: raise gr.Error("No audio file uploaded!")
-    progress(0, desc="Starting..."); await asyncio.sleep(0.1)
+    progress(0, desc="Starting...")
     try:
-        progress(0.05, desc="Preparing audio file..."); original_filename_base = os.path.basename(audio_file_path).rsplit('.', 1)[0]; stable_input_path = f"stable_input_{original_filename_base}.wav"; shutil.copy(audio_file_path, stable_input_path)
-        model_arg = "--two-stems=vocals" if "2 Stems" in stem_choice else ""; output_dir = "separated"
+        progress(0.05, desc="Preparing audio file...")
+        original_filename_base = os.path.basename(audio_file_path).rsplit('.', 1)[0]
+        stable_input_path = f"stable_input_{original_filename_base}.wav"
+        shutil.copy(audio_file_path, stable_input_path)
+        
+        model_arg = "--two-stems=vocals" if "2 Stems" in stem_choice else ""
+        output_dir = "separated"
         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..."); 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.")
-        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!")
-        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; bass_path = os.path.join(stems_path, "bass.wav") if os.path.exists(os.path.join(stems_path, "bass.wav")) else None
-        other_filename = "no_vocals.wav" if "2 Stems" in stem_choice else "other.wav"; other_path = os.path.join(stems_path, other_filename) if os.path.exists(os.path.join(stems_path, other_filename)) else None
+        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)
+        
+        stdout, stderr = await process.communicate()
+
+        if process.returncode != 0: 
+            raise gr.Error(f"Demucs failed to run. Error: {stderr.decode()[:500]}")
+
+        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!")
+            
+        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
+        bass_path = os.path.join(stems_path, "bass.wav") if os.path.exists(os.path.join(stems_path, "bass.wav")) else None
+        other_filename = "no_vocals.wav" if "2 Stems" in stem_choice else "other.wav"
+        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)
         return vocals_path, drums_path, bass_path, other_path
     except Exception as e:
-        print(f"An error occurred: {e}"); raise gr.Error(str(e))
+        print(f"An error occurred: {e}")
+        raise gr.Error(str(e))
 
 def visualize_slices(stem_audio_data, progress=gr.Progress(track_tqdm=True)):
     if stem_audio_data is None:
-        gr.Warning("This stem is empty. Cannot visualize."); return None, None, None
-    sample_rate, y_int = stem_audio_data; y = librosa.util.buf_to_float(y_int); 
-    progress(0.3, desc="Finding transients..."); onset_frames = librosa.onset.onset_detect(y=librosa.to_mono(y.T) if y.ndim > 1 else y, sr=sample_rate, wait=1, pre_avg=1, post_avg=1, post_max=1, delta=0.05)
+        gr.Warning("This stem is empty. Cannot visualize.")
+        return None, None, None
+    
+    sample_rate, y_int = stem_audio_data
+    y = librosa.util.buf_to_float(y_int)
+    
+    progress(0.3, desc="Finding transients...")
+    onset_frames = librosa.onset.onset_detect(y=librosa.to_mono(y.T) if y.ndim > 1 else y, sr=sample_rate, wait=1, pre_avg=1, post_avg=1, post_max=1, delta=0.05)
     onset_times = librosa.frames_to_time(onset_frames, sr=sample_rate)
+    
     progress(0.7, desc="Generating waveform plot...")
-    fig, ax = plt.subplots(figsize=(10, 3)); fig.patch.set_facecolor('#1f2937'); ax.set_facecolor('#111827')
+    fig, ax = plt.subplots(figsize=(10, 3))
+    fig.patch.set_facecolor('#1f2937')
+    ax.set_facecolor('#111827')
+    
     librosa.display.waveshow(y, sr=sample_rate, ax=ax, color='#32f6ff', alpha=0.7)
+    
     for t in onset_times:
         ax.axvline(x=t, color='#ff3b3b', linestyle='--', linewidth=1)
-    ax.tick_params(colors='gray'); ax.xaxis.label.set_color('gray'); ax.yaxis.label.set_color('gray'); ax.set_xlabel("Time (s)"); ax.set_ylabel("Amplitude"); ax.set_title("Detected Slices", color='white'); plt.tight_layout()
+        
+    ax.tick_params(colors='gray')
+    ax.xaxis.label.set_color('gray')
+    ax.yaxis.label.set_color('gray')
+    ax.set_xlabel("Time (s)")
+    ax.set_ylabel("Amplitude")
+    ax.set_title("Detected Slices", color='white')
+    plt.tight_layout()
+    
     progress(1, desc="Done!")
     return fig, onset_times, stem_audio_data
 
 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
+        
+    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
+            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)
+        
+    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)
 
-# --- NEW FUNCTIONS FOR MANAGING THE PACK ---
 def add_slice_to_pack(current_preview, selection_list):
     if current_preview is None:
         gr.Warning("No slice is being previewed to add.")
-        return selection_list
+        return selection_list, selection_list
     selection_list.append(current_preview)
     gr.Info(f"Slice added! You now have {len(selection_list)} slices in your pack.")
-    return selection_list
+    return selection_list, selection_list
 
 def clear_selection():
     gr.Info("Selection cleared.")
@@ -103,6 +169,7 @@ def create_final_pack(selection_list, progress=gr.Progress(track_tqdm=True)):
     progress(1, desc="Pack Ready!")
     return zip_path, gr.update(visible=True)
 
+
 # --- Create the full Gradio Interface ---
 with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red")) as demo:
     gr.Markdown("# 🎵 Loop Architect")
@@ -114,7 +181,8 @@ with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red"))
     
     with gr.Row():
         with gr.Column(scale=1):
-            gr.Markdown("### 1. Separate Stems"); audio_input = gr.Audio(type="filepath", label="Upload a Track")
+            gr.Markdown("### 1. Separate Stems")
+            audio_input = gr.Audio(type="filepath", label="Upload a Track")
             stem_options = gr.Radio(["4 Stems (Vocals, Drums, Bass, Other)", "2 Stems (Vocals + Instrumental)"], label="Separation Type", value="4 Stems (Vocals, Drums, Bass, Other)")
             submit_button = gr.Button("Separate Stems")
             with gr.Accordion("Slicing Options", open=True):
@@ -124,10 +192,18 @@ with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red"))
             
         with gr.Column(scale=2):
             with gr.Accordion("Separated Stems", open=True):
-                with gr.Row(): vocals_output = gr.Audio(label="Vocals", scale=4); slice_vocals_btn = gr.Button("Visualize Slices", scale=1)
-                with gr.Row(): drums_output = gr.Audio(label="Drums", scale=4); slice_drums_btn = gr.Button("Visualize Slices", scale=1)
-                with gr.Row(): bass_output = gr.Audio(label="Bass", scale=4); slice_bass_btn = gr.Button("Visualize Slices", scale=1)
-                with gr.Row(): other_output = gr.Audio(label="Other / Instrumental", scale=4); slice_other_btn = gr.Button("Visualize Slices", scale=1)
+                with gr.Row(): 
+                    vocals_output = gr.Audio(label="Vocals", scale=4)
+                    slice_vocals_btn = gr.Button("Visualize Slices", scale=1)
+                with gr.Row(): 
+                    drums_output = gr.Audio(label="Drums", scale=4)
+                    slice_drums_btn = gr.Button("Visualize Slices", scale=1)
+                with gr.Row(): 
+                    bass_output = gr.Audio(label="Bass", scale=4)
+                    slice_bass_btn = gr.Button("Visualize Slices", scale=1)
+                with gr.Row(): 
+                    other_output = gr.Audio(label="Other / Instrumental", scale=4)
+                    slice_other_btn = gr.Button("Visualize Slices", scale=1)
             
             gr.Markdown("### Slice Editor")
             slice_plot = gr.Plot(label="Click a region on the waveform to preview a slice")
@@ -151,12 +227,12 @@ with gr.Blocks(theme=gr.themes.Default(primary_hue="blue", secondary_hue="red"))
     slice_bass_btn.click(fn=visualize_slices, inputs=bass_output, outputs=[slice_plot, onset_times_state, active_stem_state])
     slice_other_btn.click(fn=visualize_slices, inputs=other_output, outputs=[slice_plot, onset_times_state, active_stem_state])
     
+    # Correct event listener for plot interaction
     slice_plot.select(fn=preview_slice, inputs=[active_stem_state, onset_times_state], outputs=preview_player)
     
-    add_to_pack_btn.click(fn=add_slice_to_pack, inputs=[preview_player, selected_slices_state], outputs=selected_slices_state)
-    selected_slices_state.change(fn=lambda x: x, inputs=selected_slices_state, outputs=selected_gallery) # Update gallery when state changes
+    add_to_pack_btn.click(fn=add_slice_to_pack, inputs=[preview_player, selected_slices_state], outputs=[selected_slices_state, selected_gallery])
     clear_selection_btn.click(fn=clear_selection, outputs=selected_slices_state)
     create_pack_btn.click(fn=create_final_pack, inputs=selected_slices_state, outputs=[download_zip_file, download_zip_file])
 
 # --- Launch the UI ---
-demo.launch(debug=True)
+demo.launch()