ComfyUI-EditRouter

ComfyUI - Edit Router Custom Node

This custom node detects the first edit in a batch of frames and splits the batch into:

• before_edit: frames before the cut
• after_edit: frames after the cut

If there is no edit, the node passes all frames through before_edit and returns an empty after_edit.

This is intended for video frame batches where you want to route “pre-edit” frames and “post-edit” frames into different branches of a workflow. This is useful if you want to apply VFI within a workflow, as hard edits recieve undesirable transition frames.

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Node

Edit Router

Category: video/analysis

Inputs

• images (IMAGE): A batch of frames ([B,H,W,C]).
• threshold (FLOAT, default 0.06): Sensitivity for detecting an edit.
• stable_frames (INT, default 3): Number of consecutive “stable” frames required to consider the transition finished (used to trim short fades/dissolves).

Outputs

• before_edit (IMAGE): Frames before the detected edit.
• after_edit (IMAGE): Frames after the edit (fade frames removed).

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How it works (high level)

1. Converts frames to luma (brightness) and downsamples for more stable scoring.
2. Computes a per-frame difference score between consecutive frames.
3. Finds the first frame where the score exceeds threshold (the edit boundary).
4. If the edit looks like a short transition (fade/dissolve), it trims frames until the signal returns to “normal motion” for stable_frames frames.
5. Returns the split batches.

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Tuning guide

If it misses edits

• Lower threshold (try 0.04 → 0.05).

If it triggers on normal motion / camera movement

• Raise threshold (try 0.08 → 0.12).

If it leaves a couple blended frames from a short fade

• Increase stable_frames (try 4 to 6).

If it trims too aggressively (removes real post-cut frames)

• Decrease stable_frames (try 1 to 2).

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Notes / limitations

• Detects only the first edit in the batch.
• Best for hard cuts and short fades. Long, slow transitions may be treated as “always transitioning” depending on content.
• Designed around an assumed frame rate of 16 fps (if you changed the implementation to hardcode fps).

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Install / usage

1. Place this custom node in: ComfyUI/custom_nodes/ComfyUI-EditRouter/
2. Restart ComfyUI.
3. Search for “Edit Router” in the node menu.
4. Feed an IMAGE batch (e.g. from a video loader) into the node.
5. Route before_edit and after_edit to separate branches.

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Troubleshooting

The node doesn’t show up:

• Confirm the file has NODE_CLASS_MAPPINGS and NODE_DISPLAY_NAME_MAPPINGS.
• Confirm the folder is under custom_nodes/ and ComfyUI was restarted.

after_edit is empty but I expected frames:

• If the detected edit occurs near the end of the batch, there may not be many “after” frames.
• Try lowering stable_frames or raising threshold.
• (If you still hit this) add temporary debug prints for start, end, and b.

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