stem_render: accept max_iter param, use it for refinement iterations"

stem_render.py

@@ -10,19 +10,15 @@ import gradio as gr
 logger = logging.getLogger("dj_engine")
 
 
-def render_full_set_with_stems(app_state, progress=None):
-    """Render the DJ set using demucs stem separation."""
-    if progress is None:
-        progress = gr.Progress()
+def render_full_set_with_stems(app_state, max_iter=20, progress=gr.Progress()):
+    """Render the DJ set using demucs stem separation.
     
+    max_iter: number of refinement iterations (from the UI slider)
+    """
     if not app_state.transitions:
         return None, "⚠️ Generate a set plan first"
 
-    try:
-        progress(0.02, desc="Starting stem-based render...")
-    except:
-        pass  # progress might not be callable in all contexts
-    
+    progress(0.02, desc="Starting stem-based render...")
     sr = 44100
 
     try:
@@ -32,10 +28,7 @@ def render_full_set_with_stems(app_state, progress=None):
         from stem_mixer import mix_stems
 
         device = "cuda" if torch.cuda.is_available() else "cpu"
-        try:
-            progress(0.03, desc=f"Loading demucs htdemucs ({device})...")
-        except:
-            pass
+        progress(0.03, desc=f"Loading demucs htdemucs ({device})...")
         model = get_model("htdemucs")
         model.eval().to(device)
 
@@ -44,11 +37,8 @@ def render_full_set_with_stems(app_state, progress=None):
         n_tracks = len(app_state.set_order)
         for i, tidx in enumerate(app_state.set_order):
             track = app_state.analyses[tidx]
-            try:
-                progress(0.03 + (i / n_tracks) * 0.50,
-                         desc=f"Separating stems ({i+1}/{n_tracks}): {track.filename[:30]}...")
-            except:
-                pass
+            progress(0.03 + (i / n_tracks) * 0.50,
+                     desc=f"Separating stems ({i+1}/{n_tracks}): {track.filename[:30]}...")
 
             y, _ = librosa.load(track.path, sr=model.samplerate, mono=False)
             if y.ndim == 1:
@@ -76,46 +66,45 @@ def render_full_set_with_stems(app_state, progress=None):
             logger.info(f"Separated {track.filename}: {list(stems.keys())}")
 
         # Mix using stem mixer
-        try:
-            progress(0.55, desc="Mixing with stems...")
-        except:
-            pass
+        progress(0.55, desc="Mixing with stems (surgical drum/bass swap)...")
         set_audio, set_info = mix_stems(
             all_stems, app_state.analyses, app_state.set_order,
-            progress_cb=lambda p, m: None  # stem_mixer has its own progress
+            progress_cb=lambda p, m: progress(0.55 + p * 0.35, desc=m)
         )
         method = "Demucs htdemucs → surgical drum/bass swap on downbeats"
 
     except Exception as e:
-        logger.warning(f"Stem separation failed: {e}.")
+        logger.warning(f"Stem separation failed: {e}")
         import traceback
         traceback.print_exc()
+        # Fallback to the original filter-based mixer with refinement loop
         from mixer import mix_set
-        try:
-            progress(0.10, desc="Fallback: filter-based mixing...")
-        except:
-            pass
-        set_audio, set_info = mix_set(
-            app_state.analyses, app_state.set_order, app_state.transitions,
-            progress_cb=lambda p, m: None
+        from quality_analyzer import run_refinement_loop, format_analysis_log
+        progress(0.10, desc="Fallback: filter-based mixing with refinement...")
+        set_audio, set_info, _ = run_refinement_loop(
+            mix_fn=mix_set,
+            tracks=app_state.analyses,
+            order=app_state.set_order,
+            transitions=app_state.transitions,
+            max_iter=int(max_iter),
+            progress_cb=lambda p, m: progress(0.10 + p * 0.80, desc=m)
         )
-        method = f"Filter-based (demucs failed: {e})"
+        method = f"Filter-based with {int(max_iter)} refinement iterations (demucs failed: {e})"
 
     app_state.rendered_set = set_audio
 
-    try:
-        progress(0.92, desc="Saving audio...")
-    except:
-        pass
+    progress(0.92, desc="Saving audio...")
     tmp = tempfile.NamedTemporaryFile(suffix='.wav', delete=False)
     audio_int16 = (set_audio.T * 32767).astype(np.int16)
     scipy.io.wavfile.write(tmp.name, sr, audio_int16)
 
+    # Summary
     summary = f"# ✅ DJ Set Rendered\n\n"
     summary += f"- **Total duration:** {set_info.get('total_duration', 0):.1f}s "
     summary += f"({set_info.get('total_duration', 0)/60:.1f} min)\n"
     summary += f"- **Tracks:** {len(set_info.get('tracks', []))}\n"
     summary += f"- **Method:** {method}\n\n"
+
     summary += "## Tracklist\n"
     for i, t in enumerate(set_info.get('tracks', [])):
         fn = t.get('filename', '?')
@@ -124,4 +113,12 @@ def render_full_set_with_stems(app_state, progress=None):
         extra = f" (×{stretch:.3f})" if abs(stretch - 1.0) > 0.003 else ""
         summary += f"{i+1}. **{fn}** — starts at {tl:.0f}s{extra}\n"
 
+    if set_info.get('transitions'):
+        summary += "\n## Transitions\n"
+        for t in set_info['transitions']:
+            if isinstance(t, dict):
+                summary += f"- {t}\n"
+            else:
+                summary += f"- {t}\n"
+
     return tmp.name, summary