Fix GPU encoding black frames and improve debug logging

- Add CUDA sync before encoding to ensure RGB->NV12 kernel completes
- Add debug logging for frame data validation (sum check)
- Handle GPUFrame objects in GPUHLSOutput.write()
- Fix cv2.resize for CuPy arrays (use cupyx.scipy.ndimage.zoom)
- Fix fused pipeline parameter ordering (geometric first, color second)
- Add raindrop-style ripple with random position/freq/decay/amp
- Generate final VOD playlist with #EXT-X-ENDLIST

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

sexp_effects/primitive_libs/streaming_gpu.py

@@ -894,7 +894,7 @@ def prim_fused_pipeline(img, effects_list, **dynamic_params):
     Returns:
         Processed image as GPU array
 
-    Supported ops: rotate, zoom, ripple, invert, hue_shift, brightness
+    Supported ops: rotate, zoom, ripple, invert, hue_shift, brightness, resize
     """
     global _FUSED_CALL_COUNT
     _FUSED_CALL_COUNT += 1
@@ -904,8 +904,34 @@ def prim_fused_pipeline(img, effects_list, **dynamic_params):
     # Normalize effects list - convert Keyword keys to strings
     effects_list = [_normalize_effect_dict(e) for e in effects_list]
 
+    # Handle resize separately - it changes dimensions so must happen before fused kernel
+    resize_ops = [e for e in effects_list if e.get('op') == 'resize']
+    other_effects = [e for e in effects_list if e.get('op') != 'resize']
+
+    # Apply resize first if needed
+    if resize_ops:
+        for resize_op in resize_ops:
+            target_w = int(resize_op.get('width', 640))
+            target_h = int(resize_op.get('height', 360))
+            # Wrap in GPUFrame if needed
+            if isinstance(img, GPUFrame):
+                img = gpu_resize(img, (target_w, target_h))
+                img = img.gpu if img.is_on_gpu else img.cpu
+            else:
+                frame = GPUFrame(img, on_gpu=hasattr(img, '__cuda_array_interface__'))
+                img = gpu_resize(frame, (target_w, target_h))
+                img = img.gpu if img.is_on_gpu else img.cpu
+
+    # If no other effects, just return the resized image
+    if not other_effects:
+        return img
+
+    # Update effects list to exclude resize ops
+    effects_list = other_effects
+
     if not _FUSED_KERNELS_AVAILABLE:
         # Fallback: apply effects one by one
+        print(f"[FUSED FALLBACK] Using fallback path for {len(effects_list)} effects", file=sys.stderr)
         # Wrap in GPUFrame if needed (GPU functions expect GPUFrame objects)
         if isinstance(img, GPUFrame):
             result = img
@@ -922,20 +948,27 @@ def prim_fused_pipeline(img, effects_list, **dynamic_params):
                 result = gpu_zoom(result, amount)
             elif op == 'hue_shift':
                 degrees = effect.get('degrees', 0)
-                result = gpu_hue_shift(result, degrees)
+                if abs(degrees) > 0.1:  # Only apply if significant shift
+                    result = gpu_hue_shift(result, degrees)
             elif op == 'ripple':
-                result = gpu_ripple(result,
-                    amplitude=dynamic_params.get('ripple_amplitude', effect.get('amplitude', 10)),
-                    frequency=effect.get('frequency', 8),
-                    decay=effect.get('decay', 2),
-                    phase=dynamic_params.get('ripple_phase', effect.get('phase', 0)),
-                    cx=effect.get('center_x'),
-                    cy=effect.get('center_y'))
+                amplitude = dynamic_params.get('ripple_amplitude', effect.get('amplitude', 10))
+                if amplitude > 0.1:  # Only apply if amplitude is significant
+                    result = gpu_ripple(result,
+                        amplitude=amplitude,
+                        frequency=effect.get('frequency', 8),
+                        decay=effect.get('decay', 2),
+                        phase=dynamic_params.get('ripple_phase', effect.get('phase', 0)),
+                        cx=effect.get('center_x'),
+                        cy=effect.get('center_y'))
             elif op == 'brightness':
                 factor = effect.get('factor', 1.0)
                 result = gpu_contrast(result, factor, 0)
             elif op == 'invert':
-                result = gpu_invert(result)
+                amount = effect.get('amount', 0)
+                if amount > 0.5:  # Only invert if amount > 0.5
+                    result = gpu_invert(result)
+            else:
+                raise ValueError(f"Unsupported fused pipeline operation: '{op}'. Supported ops: rotate, zoom, hue_shift, ripple, brightness, invert, resize")
         # Return raw array, not GPUFrame (downstream expects arrays with .flags attribute)
         if isinstance(result, GPUFrame):
             return result.gpu if result.is_on_gpu else result.cpu