Kling Video 4.0 Flash Video Edit.

Kling Video 4.0 Flash Video Edit Overview

Kling Video 4.0 Flash Video Edit transforms an existing source video using a required editing prompt and optional references. This model is part of the Kling Video 4.0 Flash family. The videos array identifies exactly one base_video as the footage to transform, with optional image, feature-video and Element references for direction. Output framing can be adaptive or selected explicitly.

Provide a nonempty prompt and a videos array containing exactly one base_video. Add optional feature_video, image or existing Element references, then set duration, resolution and aspect_ratio. Output durations run from 3 to 20 seconds at 720p. Use the model for short creative clips, concept development and application workflows where the intended action fits a single short scene. Review the result for the details that matter to your project before selecting it as a finished asset.

Capabilities

• Transform an existing source video with a required editing prompt.
• Identify exactly one base_video and add optional feature_video references.
• Provide images with first_frame or refer_image roles for guidance.
• Supply existing Elements, including at most three Video Character Elements.
• Request an integer duration from 3 through 20 seconds at 720p.
• Select adaptive, 21:9, 16:9, 9:16 or 1:1 framing.
• Distinguish supporting references with unique ids across all reference types.

Use Cases for Kling Video 4.0 Flash Video Edit

Creators can explore visual treatments for existing footage. For example, "Transform the source into a pencil-sketch look while keeping the subject’s action recognizable" communicates both an intended change and a preservation goal.

Marketers can develop alternative campaign looks from one source clip. "Give the scene warm evening lighting and keep the product prominent" provides a focused starting point. Inspect the output for unintended changes to product appearance before using it publicly.

Designers can combine source footage with reference images to communicate a desired direction. Assign clear reference ids and explain which asset supplies the desired appearance instead of assuming that the system knows each upload’s role.

Developers can expose a prompt-driven editing step in an existing video workflow. The Kling Video 4.0 Flash Video Edit API separates the base clip from supporting references, making source selection explicit in the request.

Tips and Tricks

State the change first, then name the source details that should remain recognizable. Keep the initial edit narrow so you can tell whether the instruction had the intended effect before adding more references.

For a visual treatment, try: "Transform the source clip into a soft pencil-sketch style. Keep the main subject and overall camera movement recognizable." For a scene adjustment: "Give the source scene warm sunset lighting while keeping the subject’s action and the camera direction consistent."

Use exactly one base_video and label extra clips as feature_video. Give referenced assets unique ids and explain how they should influence the edit. Keep the requested duration aligned with the source where practical, and check the finished result for altered faces, object shapes and unintended visual changes.

Technical Specifications

• Output: generated video; a successful task provides a video URL.
• Duration: integer seconds from 3 through 20; default 10 seconds.
• Resolution: 720p only; default 720p.
• Required: prompt and videos, with exactly one base_video.
• Video media: MP4/MOV, at most 300 MB each, 3–20 seconds, 24–60 fps; dimensions 700–4553 pixels, maximum 8,294,400 pixels.
• Optional references: images, feature_video entries and existing Elements.
• Framing: adaptive by default; also 21:9, 16:9, 9:16 and 1:1.
• Prompt limits: 1–26,000 characters for English-only text or up to 11,000 for non-English-only text. Mixed-language input must satisfy E/26000 + N/11000 ≤ 1; Kling enforces the weighted limit.
• Processing: asynchronous. No fixed completion time, output codec or configurable output frame rate is specified by the current integration.

Things to Be Aware Of

This is generative video editing, not a guarantee that every unmentioned source detail stays unchanged. Review the clip, especially faces, lettering and product features. Keep the source and all supporting URLs available during processing. Combined reference counts and actual media properties are checked by the provider. A successful schema check alone does not prove that every source file or existing Element ID will be accepted.

Respect the language-weighted prompt limit and send only documented fields. Describe unwanted details in the same prompt instead of adding a negative_prompt parameter. Review a simple request before preparing variations.

Key Considerations

Supply exactly one base_video and describe what should change. Framing defaults to adaptive. Check source and reference media properties before submission, and keep their URLs accessible throughout processing. Start with a focused edit before combining several visual changes or introducing a larger reference set.

Billing is calculated per task from the reported charge, rather than a published flat price per clip. No fixed per-second estimate is present in this model’s current catalog. Review the final billed cost before budgeting a large batch.

Limitations

A prompt and videos array containing exactly one base_video are required. Videos plus Video Character Elements cannot exceed five, and all references together cannot exceed 15. Combined video duration must stay within 3–20 seconds. Output is 720p only. Voice references, middle-frame and last-frame image roles are not accepted. Exact cuts, source preservation and deterministic edits are not guaranteed. Check important details before publication.