Normalize input/output names across nodes

- SourcePrep output: source_clip → trimmed_clip (distinguish from input)
- MergeBack input: original_clip → source_clip (matches SourcePrep's
  input — same video wire from Load Video)
- MergeBack input: original_clip_2 → source_clip_2 (matches SourcePrep)
- Update README wiring diagram and tables

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -35,7 +35,7 @@ Irrelevant widgets are automatically hidden based on the selected mode.
 
 | Output | Type | Description |
 |---|---|---|
-| `source_clip` | IMAGE | Trimmed frames — wire to mask generator's source_clip. |
+| `trimmed_clip` | IMAGE | Trimmed frames — wire to mask generator's source_clip. |
 | `mode` | ENUM | Selected mode — wire to mask generator's mode. |
 | `split_index` | INT | Adjusted for the trimmed clip — wire to mask generator. |
 | `edge_frames` | INT | Adjusted/passed through — wire to mask generator. |
@@ -270,12 +270,12 @@ Irrelevant widgets are automatically hidden based on the selected blend method.
 
 | Input | Type | Default | Description |
 |---|---|---|---|
-| `original_clip` | IMAGE | — | Full original video (before any trimming). |
+| `source_clip` | IMAGE | — | Full original video (before any trimming). Same source as VACE Source Prep's source_clip. |
 | `vace_output` | IMAGE | — | VACE sampler output. |
 | `vace_pipe` | VACE_PIPE | — | Pipe from VACE Source Prep carrying mode, trim bounds, and context counts. |
 | `blend_method` | ENUM | `optical_flow` | `none` (hard cut), `alpha` (linear crossfade), or `optical_flow` (motion-compensated). |
 | `of_preset` | ENUM | `balanced` | Optical flow quality: `fast`, `balanced`, `quality`, `max`. |
-| `original_clip_2` | IMAGE | *(optional)* | Second original clip for Join Extend with two separate clips. |
+| `source_clip_2` | IMAGE | *(optional)* | Second original clip for Join Extend with two separate clips. |
 
 ### Outputs
 
@@ -287,7 +287,7 @@ Irrelevant widgets are automatically hidden based on the selected blend method.
 
 **Pass-through modes** (Edge Extend, Frame Interpolation, Keyframe, Video Inpaint): returns `vace_output` as-is — the VACE output IS the final result for these modes.
 
-**Splice modes** (End, Pre, Middle, Join, Bidirectional, Replace): reconstructs `original[:trim_start] + vace_output + original[trim_end:]`, then blends across the full context zones at each seam. For two-clip Join Extend, the tail comes from `original_clip_2` instead.
+**Splice modes** (End, Pre, Middle, Join, Bidirectional, Replace): reconstructs `source_clip[:trim_start] + vace_output + source_clip[trim_end:]`, then blends across the full context zones at each seam. For two-clip Join Extend, the tail comes from `source_clip_2` instead.
 
 Context frame counts (`left_ctx`, `right_ctx`) are carried in the `vace_pipe` and determined automatically by VACE Source Prep based on the mode and input_left/input_right settings. Blending uses a smooth alpha ramp across the entire context zone. Optical flow blending warps both frames along the motion field before blending, reducing ghosting on moving subjects.
 
@@ -311,11 +311,11 @@ Merge:     result = original[0:121] + vace[0:81] + original[153:274]
 ```
 [Load Video]
      │
-     ├─ source_clip ──→ [VACESourcePrep] ─┬─ source_clip ──→ [MaskGen] ─→ [Sampler]
+     ├─ source_clip ──→ [VACESourcePrep] ─┬─ trimmed_clip ──→ [MaskGen] ─→ [Sampler]
-     │                                     ├─ mode ──────────→ [MaskGen]       │
+     │                                     ├─ mode ───────────→ [MaskGen]       │
-     │                                     └─ vace_pipe ─────────────────┐     │
+     │                                     └─ vace_pipe ──────────────────┐     │
      │                                                                    │     │
-     └─ original_clip ──────────────────────────────────────→ [VACEMergeBack] ←┘
+     └─ source_clip ───────────────────────────────────────→ [VACEMergeBack] ←┘
                                                                   vace_output
 ```
 

merge_node.py

@@ -90,7 +90,7 @@ Pass-through modes (Edge Extend, Frame Interpolation, Keyframe, Video Inpaint):
 Splice modes (End, Pre, Middle, Join, Bidirectional, Replace):
   Reconstructs original[:trim_start] + vace_output + original[trim_end:]
   with automatic blending across the full context zones.
-  For two-clip Join Extend, connect original_clip_2 — the tail comes from the second clip.
+  For two-clip Join Extend, connect source_clip_2 — the tail comes from the second clip.
 
 Blend methods:
   none          — Hard cut at seams (fastest)
@@ -101,18 +101,18 @@ Blend methods:
     def INPUT_TYPES(cls):
         return {
             "required": {
-                "original_clip": ("IMAGE", {"description": "Full original video (before any trimming)."}),
+                "source_clip": ("IMAGE", {"description": "Full original video (before any trimming)."}),
                 "vace_output": ("IMAGE", {"description": "VACE sampler output."}),
                 "vace_pipe": ("VACE_PIPE", {"description": "Pipe from VACE Source Prep carrying mode, trim bounds, and context counts."}),
                 "blend_method": (["optical_flow", "alpha", "none"], {"default": "optical_flow", "description": "Blending method at seams."}),
                 "of_preset": (["fast", "balanced", "quality", "max"], {"default": "balanced", "description": "Optical flow quality preset."}),
             },
             "optional": {
-                "original_clip_2": ("IMAGE", {"description": "Second original clip for Join Extend with two separate clips."}),
+                "source_clip_2": ("IMAGE", {"description": "Second original clip for Join Extend with two separate clips."}),
             },
         }
 
-    def merge(self, original_clip, vace_output, vace_pipe, blend_method, of_preset, original_clip_2=None):
+    def merge(self, source_clip, vace_output, vace_pipe, blend_method, of_preset, source_clip_2=None):
         mode = vace_pipe["mode"]
         trim_start = vace_pipe["trim_start"]
         trim_end = vace_pipe["trim_end"]
@@ -126,13 +126,13 @@ Blend methods:
         # Splice modes: reconstruct full video
         two_clip = vace_pipe.get("two_clip", False)
         V = vace_output.shape[0]
-        head = original_clip[:trim_start]
+        head = source_clip[:trim_start]
-        if two_clip and original_clip_2 is not None:
+        if two_clip and source_clip_2 is not None:
-            tail = original_clip_2[trim_end:]
+            tail = source_clip_2[trim_end:]
-            right_orig = original_clip_2
+            right_orig = source_clip_2
         else:
-            tail = original_clip[trim_end:]
+            tail = source_clip[trim_end:]
-            right_orig = original_clip
+            right_orig = source_clip
         result = torch.cat([head, vace_output, tail], dim=0)
 
         if blend_method == "none" or (left_ctx == 0 and right_ctx == 0):
@@ -146,7 +146,7 @@ Blend methods:
         # Blend across full left context zone
         for j in range(left_ctx):
             alpha = (j + 1) / (left_ctx + 1)
-            result[trim_start + j] = blend_frame(original_clip[trim_start + j], vace_output[j], alpha)
+            result[trim_start + j] = blend_frame(source_clip[trim_start + j], vace_output[j], alpha)
 
         # Blend across full right context zone
         for j in range(right_ctx):

nodes.py

@@ -300,7 +300,7 @@ class VACESourcePrep:
     FUNCTION = "prepare"
     RETURN_TYPES = ("IMAGE", VACE_MODES, "INT", "INT", "MASK", "STRING", "VACE_PIPE")
     RETURN_NAMES = (
-        "source_clip", "mode", "split_index", "edge_frames",
+        "trimmed_clip", "mode", "split_index", "edge_frames",
         "inpaint_mask", "keyframe_positions", "vace_pipe",
     )
     OUTPUT_TOOLTIPS = (