Kling 4.0 Flash Reference To Video

Generate videos with Kling 4.0 Flash from reference images, reference videos, and elements. Mention your materials in the prompt using @image_1, @video_1, or custom @name tags. Standalone voices is not supported; bind character audio on the element's voice_url.

Materials and References

All three material types are optional. When none are provided, the request behaves as plain text-to-video. Once provided, mention them in prompt as shown below:

Material	Mention syntax	Limit
Reference images `image_urls`	`@image_1`, `@image_2`, …	10 images
Reference videos `video_urls`	`@video_1`, `@video_2`, …	5 videos
Elements `elements`	`@name`	7 items, of which at most 3 can be video elements

Reference videos plus video elements cannot exceed 5 in total. The three material types combined cannot exceed 15.

Combined duration of all reference videos and video elements must be 2–20 seconds. If it is outside that range, the completion callback returns a failure.

An image element needs 2–4 images, with the first as the primary view. A video element needs one 3–8 second single-shot character video.

Custom names must be 1–20 characters of Chinese characters, letters, digits, or underscores; unique (case-insensitive); and must not use reserved names such as image_N, video_N, keyframe_N, object_N, audio_N, first_frame, or last_frame.

Mentioning an undeclared material is rejected immediately and the task is not created.

Output resolution is always 720p. Duration is 3–20 seconds.

When aspect_ratio is omitted, the model uses auto if any reference material is provided, and 16:9 when none are. When video_urls is provided, keep_original_sound controls whether the original audio is kept.

Query Task Status

After submitting a task, you can check the task progress and retrieve generation results via the unified query endpoint:

Get Task Details

Learn how to check the task status and obtain the generated results

In the production environment, it is recommended to use the callBackUrl parameter to receive the automatic notification upon completion of the generation, rather than polling the status endpoint.

Market Overview

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General API

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Bearer Token

Provide your bearer token in the

Authorization

header when making requests to protected resources.

Example:

Authorization: Bearer ********************

curl --location 'https://api.kie.ai/api/v1/jobs/createTask' \ --header 'Authorization: Bearer <token>' \ --header 'Content-Type: application/json' \ --data '{ "model": "kling-4.0/flash-reference-to-video", "callBackUrl": "https://your-domain.com/api/callback", "input": { "prompt": "Replace the environment and characters throughout the video with the content from Image.", "image_urls": [ "https://static.aiquickdraw.com/tools/example/1793864877785_DrXOIEka.png" ], "video_urls": [ "https://static.aiquickdraw.com/tools/example/1793864807765_yRE8tJUe.mp4" ], "keep_original_sound": false, "duration": 5, "resolution": "720p", "aspect_ratio": "auto", "elements": [ { "name": "test", "type": "image", "image_urls": [ "https://tempfileb.aiquickdraw.com/kieai/market/1793878290792_SdXlPHYn.jpeg" ], "tag": "character", "description": "测试实测", "voice_url": "https://tempfileb.aiquickdraw.com/kieai/market/1793878312680_g5wLYejf.mp3" } ] } }'

Kling 4.0 Flash Reference To Video

Materials and References

Query Task Status

Callbacks

videoTaskCompleted

Request

Responses

Kling 4.0 Flash Reference To Video

Materials and References#

Query Task Status#

Related Resources#

Callbacks

videoTaskCompleted

Request

Responses

Materials and References

Query Task Status

Related Resources