Update app.py

app.py

@@ -173,14 +173,29 @@ def ai_mastering_chain(audio_path, genre="Pop", target_lufs=-14.0):
     loudness = meter.integrated_loudness(samples.astype(np.float64) / 32768.0)
     gain_db = target_lufs - loudness
     final_audio = eq_audio + gain_db
-
-    # Final limiting
     final_audio = apply_limiter(final_audio)
 
     out_path = os.path.join(tempfile.gettempdir(), "mastered_output.wav")
     final_audio.export(out_path, format="wav")
     return out_path
 
+# === Harmonic Saturation / Exciter – Now Defined Before Use ===
+def harmonic_saturation(audio, saturation_type="Tube", intensity=0.2):
+    samples = np.array(audio.get_array_of_samples()).astype(np.float32)
+
+    if saturation_type == "Tube":
+        saturated = np.tanh(intensity * samples)
+    elif saturation_type == "Tape":
+        saturated = np.where(samples > 0, 1 - np.exp(-intensity * samples), -1 + np.exp(intensity * samples))
+    elif saturation_type == "Console":
+        saturated = np.clip(samples, -32768, 32768) * intensity
+    elif saturation_type == "Mix Bus":
+        saturated = np.log1p(np.abs(samples)) * np.sign(samples) * intensity
+    else:
+        saturated = samples
+
+    return array_to_audiosegment(saturated.astype(np.int16), audio.frame_rate, channels=audio.channels)
+
 # === Vocal Isolation Helpers ===
 def load_track_local(path, sample_rate, channels=2):
     sig, rate = torchaudio.load(path)
@@ -428,6 +443,20 @@ with gr.Blocks(title="AI Audio Studio", css="style.css") as demo:
             allow_flagging="never"
         )
 
+    # --- Harmonic Saturation / Exciter – Now Included ===
+    with gr.Tab("🧬 Harmonic Saturation"):
+        gr.Interface(
+            fn=harmonic_saturation,
+            inputs=[
+                gr.Audio(label="Upload Track", type="filepath"),
+                gr.Dropdown(choices=["Tube", "Tape", "Console", "Mix Bus"], label="Saturation Type", value="Tube"),
+                gr.Slider(minimum=0.1, maximum=1.0, value=0.2, label="Intensity")
+            ],
+            outputs=gr.Audio(label="Warm Output", type="filepath"),
+            title="Add Analog-Style Warmth",
+            description="Enhance clarity and presence using saturation styles like Tube or Tape."
+        )
+
     # --- Remix Mode ---
     with gr.Tab("🎛 Remix Mode"):
         gr.Interface(
@@ -445,20 +474,6 @@ with gr.Blocks(title="AI Audio Studio", css="style.css") as demo:
             clear_btn=None
         )
 
-    # --- Harmonic Saturation / Exciter ===
-    with gr.Tab("🧬 Harmonic Saturation"):
-        gr.Interface(
-            fn=harmonic_saturation,
-            inputs=[
-                gr.Audio(label="Upload Track", type="filepath"),
-                gr.Dropdown(choices=["Tube", "Tape", "Console", "Mix Bus"], label="Saturation Type", value="Tube"),
-                gr.Slider(minimum=0.1, maximum=1.0, value=0.2, label="Intensity")
-            ],
-            outputs=gr.Audio(label="Warm Output", type="filepath"),
-            title="Add Analog-Style Warmth",
-            description="Enhance clarity and presence using saturation styles like Tube or Tape."
-        )
-
     # --- Preset Cards Gallery ===
     with gr.Tab("🎛 Preset Gallery"):
         gr.Markdown("### Select a preset visually")