ByteDance2FirstLastFrameNode - ComfyUI Built-in Node Documentation

This node generates a video from a required first frame image and an optional last frame image using ByteDance Seedance models. You describe the video with a text prompt; the first frame guides the start of the video and the last frame guides the end. It supports Seedance 2.5 and the Seedance 2.0 family (Seedance 2.0, Seedance 2.0 Fast, and Seedance 2.0 Mini). Selecting the Seedance 2.5 Draft model renders a fast 480p preview instead; connect the resulting draft_task_id to the ByteDance Seedance 2.5 Draft to Final Video node to render the 1080p final.

Inputs

Common Inputs

Parameter	Description	Data Type	Required	Range
`model`	Seedance 2.5 for the newest model, videos up to 30 seconds and mp4 output; Seedance 2.5 Draft for a fast 480p preview whose `draft_task_id` output renders the 1080p final in the ByteDance Seedance 2.5 Draft to Final Video node; Seedance 2.0 for maximum quality and 4k; Fast for speed optimization; Mini for the fastest, lowest-cost generation. Selecting a model reveals model-specific inputs below.	DYNAMIC_COMBO	Yes	`"Seedance 2.5"` `"Seedance 2.5 Draft"` `"Seedance 2.0"` `"Seedance 2.0 Fast"` `"Seedance 2.0 Mini"`
`first_frame`	First frame image for the video.	IMAGE	No	-
`last_frame`	Last frame image for the video.	IMAGE	No	-
`first_frame_asset_id`	Seedance asset_id to use as the first frame. Mutually exclusive with the `first_frame` image input. Default is an empty string.	STRING	No	-
`last_frame_asset_id`	Seedance asset_id to use as the last frame. Mutually exclusive with the `last_frame` image input. Default is an empty string.	STRING	No	-
`seed`	Seed controls whether the node should re-run; results are non-deterministic regardless of seed. Default is 0.	INT	Yes	0 to 2147483647
`watermark`	Whether to add a watermark to the video. Default is False.	BOOLEAN	Yes	False True

Seedance 2.5 Inputs

These inputs appear when Seedance 2.5 is selected.

Parameter	Description	Data Type	Required	Range
`prompt`	Text prompt for video generation. Put spoken lines in double quotes to steer the generated dialogue.	STRING	Yes	-
`resolution`	Resolution of the output video. Default is 720p.	COMBO	Yes	`"480p"` `"720p"` `"1080p"`
`duration`	Duration of the output video in seconds (4-30). Default is 5.	INT	Yes	4 to 30
`generate_audio`	Enable audio generation for the output video. Default is True.	BOOLEAN	Yes	False True
`output_format`	Container format of the output video. Default is mp4.	COMBO	Yes	`"mp4"`

Seedance 2.5 Draft Inputs

These inputs appear when Seedance 2.5 Draft is selected. The parameter set matches Seedance 2.5 above, except that resolution offers only "480p" (default "480p").

Seedance 2.0 Inputs

These inputs appear when Seedance 2.0 is selected.

Parameter	Description	Data Type	Required	Range
`prompt`	Text prompt for video generation.	STRING	Yes	-
`resolution`	Resolution of the output video.	COMBO	Yes	`"480p"` `"720p"` `"1080p"` `"4k"`
`ratio`	Aspect ratio of the output video. Default is `adaptive`, which uses the nearest supported ratio to the input frame’s aspect ratio.	COMBO	Yes	`"16:9"` `"4:3"` `"1:1"` `"3:4"` `"9:16"` `"21:9"` `"adaptive"`
`duration`	Duration of the output video in seconds (4-15). Default is 7.	INT	Yes	4 to 15
`generate_audio`	Enable audio generation for the output video. Default is True.	BOOLEAN	Yes	False True

Seedance 2.0 Fast and Seedance 2.0 Mini Inputs

Shared by Seedance 2.0 Fast and Seedance 2.0 Mini.

Parameter	Description	Data Type	Required	Range
`prompt`	Text prompt for video generation.	STRING	Yes	-
`resolution`	Resolution of the output video.	COMBO	Yes	`"480p"` `"720p"`
`ratio`	Aspect ratio of the output video. Default is `adaptive`, which uses the nearest supported ratio to the input frame’s aspect ratio.	COMBO	Yes	`"16:9"` `"4:3"` `"1:1"` `"3:4"` `"9:16"` `"21:9"` `"adaptive"`
`duration`	Duration of the output video in seconds (4-15). Default is 7.	INT	Yes	4 to 15
`generate_audio`	Enable audio generation for the output video. Default is True.	BOOLEAN	Yes	False True

Parameter Constraints

You must provide the first frame either as a first_frame image or as a first_frame_asset_id. Providing both raises an error; providing neither also raises an error.
The last_frame and last_frame_asset_id inputs are optional, but you cannot provide both for the same frame.
Asset IDs must reference existing, active Seedance Image assets.
The prompt input is required and cannot be empty.
Every run returns its task ID as draft_task_id, but only a Seedance 2.5 Draft run’s ID can be rendered by the ByteDance Seedance 2.5 Draft to Final Video node. With any other model the output must be left unconnected, otherwise the run fails.
With Seedance 2.5, the output aspect ratio is always adaptive and follows the first frame’s own aspect ratio, so no ratio input is shown.
With Seedance 2.0 family models and local frame images, the images are center-cropped and resized to the target output resolution and ratio before generation. When ratio is adaptive, the nearest supported ratio to the input image is used.
Local frame images are validated for supported aspect ratio and dimensions; oversized images are downscaled.

Outputs

Output Name	Description	Data Type
`output`	The generated video.	VIDEO
`draft_task_id`	Task ID returned by the run. Only a `Seedance 2.5 Draft` run produces a draft that the ByteDance Seedance 2.5 Draft to Final Video node can render; with any other model the output must be left unconnected, otherwise the run fails.	STRING

This documentation was AI-generated. If you find any errors or have suggestions for improvement, please feel free to contribute! Edit on GitHub

Source fingerprint (SHA-256): 363f1baac1685c2dada0e64a0b339f6ab2671161dccb002eb81f6b4f0d0aa243

​Inputs

​Common Inputs

​Seedance 2.5 Inputs

​Seedance 2.5 Draft Inputs

​Seedance 2.0 Inputs

​Seedance 2.0 Fast and Seedance 2.0 Mini Inputs

​Outputs