Wan VACE Prep

ComfyUI nodes for Wan VACE workflows. Control video and mask creation for transitions and extensions, plus workflow utilites.

Quick Start

Install via ComfyUI Manager: Search for "Wan VACE Prep"

Or clone this repository:

cd /path/to/comfyui/custom_nodes
git clone https://github.com/stuttlepress/ComfyUI-Wan-VACE-Prep

Nodes

Wan VACE Prep

For smoothly joining two video clips together. Builds VACE controls for the transition using context frames from each clip to guide frame generation.

• Builds VACE control video and mask from context frames in both clips
• Outputs video segments for final assembly

Parameters:

Parameter	Default	Description
context_frames	8	Reference frames from each video edge that VACE uses for interpolation. These frames guide the model and are preserved in the output. Must be a multiple of 4.
replace_frames	8	Number of frames at each transition edge to discard and regenerate. These create the actual transition blend zone. Must be a multiple of 4.
add_frames	0	Number of completely new frames to generate between the two clips, extending the transition duration. Must be 0 or a multiple of 4.

Outputs:

Output	Description
control_video	VACE control video input
control_mask	VACE control mask input
width, height, length	Control video dimensions
start_images	Video 1 segment that precedes context frames and the transition
end_images	Video 2 segment that comes after the transition and context frames

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Wan VACE Prep Batch

Batch-aware version of Wan VACE Prep for processing multiple video pairs. Handles first/last iteration edge cases.

Parameters:

Parameter	Default	Description
video_1		First video in the pair (IMAGE type)
video_2		Second video in the pair (IMAGE type)
is_first	false	Set true for first iteration (index=0) - includes full beginning of video_1 in start_images
is_last	false	Set true for last iteration - includes full ending of video_2 in end_images
context_frames	8	Reference frames from each video edge that VACE uses for interpolation. These frames guide the model and are preserved in the output. Must be a multiple of 4.
replace_frames	8	Number of frames at each transition edge to discard and regenerate. These create the actual transition blend zone. Must be a multiple of 4.
new_frames	0	Number of completely new frames to generate between the two clips, extending the transition duration. Must be 0 or a multiple of 4.
debug	false	Log diagnostic information to the console

Outputs:

Output	Description
control_video	VACE control video input (context frames + placeholder for generation)
control_mask	VACE control mask input (masks generation region)
width, height, length	Control video dimensions
start_images	Video segment from video_1 to preserve (excludes transition region)
end_images	Video segment from video_2 to preserve (only populated on last iteration)

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Wan VACE Batch Context

Establishes iteration context for batch video processing workflows. Manages file paths, iteration tracking, and provides first/last flags for proper handling of video sequence boundaries.

Parameters:

Parameter	Default	Description
input_list		List of video filenames to process (STRING, force input)
input_dir		Directory containing input videos
project_name	.	Project name - workflow files created under ComfyUI/output/project_name. Use period (.) for no project name.
index	0	Current iteration index (0-based). Valid range: 0 to (number of videos - 2)
debug	false	Log iteration details to the console

Outputs:

Output	Description
work_dir	Working directory path for intermediate files
workfile_prefix	Filename prefix for this iteration's work files
is_first	True if this is the first iteration (index=0)
is_last	True if this is the last iteration
video_1_filename	Full path to first video in current pair
video_2_filename	Full path to second video in current pair

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Wan VACE Extend

For smoothly extending a video. Context frames from before the chosen extension point are used to build a control video for VACE conditioning.

• Extends from arbitrary frame position
• Builds VACE control video and mask from context frames in the input video
• Outputs video segment preceding the extension for video reassembly

Parameters:

Parameter	Default	Description
extend_from_idx	-1	Frame to extend from (negative counts from end, e.g., -1 = last frame)
context_frames	8	Number of reference frames preceding extend_from_idx that VACE uses for interpolation. These frames guide the model and are preserved in the output. Must be a multiple of 4.
new_frames	25	Number of new frames to generate (must be 4n+1: e.g., 1, 5, 9, 13, 17, 25...)

Outputs:

Output	Description
control_video	VACE control video input
control_mask	VACE control mask input
width, height, length	Control video dimensions
start_images	Video segment that precedes the context frames and the start of the extension

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Load Videos From Folder (Simple)

Load all videos from a folder for batch processing. A simplified, dependency-free alternative to KJNodes' LoadVideosFromFolder (which depends on VideoHelperSuite and can have problems in some environments).

• Formats: webm, mp4, mkv, gif, mov
• All videos must have identical resolution
• No external dependencies

Parameters:

Parameter	Default	Description
folder_path		Full pathname of the directory holding input videos.

Outputs:

Output	Description
images	Concatenated image batch ready for video creation.

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Technical Note

The Wan model likes to generate 4n+1 frames at a time. If you ask it for some other amount, it will silently round your request down to the nearest 4n+1. For this reason, parameters are restricted to multiples of 4 or 4n+1 and when necessary, the node adds +1 to the number of generated frames.

License

MIT License - feel free to use, modify, and distribute.