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Extend AI Video

Extend existing AI-generated videos to create longer sequences.

Usage Guide

  • Add additional segments to your AI-generated videos
  • Maintain visual consistency while extending narratives
  • Create longer sequences for storytelling or demonstrations

Parameter Details

  • taskId identifies the original video to extend
  • prompt guides how the video should continue
  • quality video resolution, optional values are 720p or 1080p.
  • waterMark video watermark text content, empty string means no watermark

Developer Notes

  • Extended videos are stored for 14 days before automatic deletion
  • Extension maintains the same aspect ratio as the original video
  • Extension works best when continuing the same subject/theme as the original video
Rate limits and quotas are enforced by Apikley and may differ from upstream providers.

OpenAPI

runway-api/runway-api.json post /api/v1/runway/extend
openapi: 3.0.0
info:
  title: Runway API
  description: Apikley Runway API Documentation
  version: 1.0.0
  contact:
    name: Technical Support
    email: [email protected]
servers:
  - url: https://api.apikley.ru
    description: API Server
security:
  - BearerAuth: []
paths:
  /api/v1/runway/extend:
    post:
      summary: Extend AI Video
      description: >-
        Extend existing AI-generated videos to create longer sequences.


        ### Usage Guide

        - Add additional segments to your AI-generated videos

        - Maintain visual consistency while extending narratives

        - Create longer sequences for storytelling or demonstrations


        ### Parameter Details

        - `taskId` identifies the original video to extend

        - `prompt` guides how the video should continue

        - `quality` video resolution, optional values are 720p or 1080p. 

        - `waterMark` video watermark text content, empty string means no
        watermark


        ### Developer Notes

        - Extended videos are stored for 14 days before automatic deletion

        - Extension maintains the same aspect ratio as the original video

        - Extension works best when continuing the same subject/theme as the
        original video
      operationId: extend-ai-video
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - taskId
                - prompt
                - quality
              properties:
                taskId:
                  type: string
                  description: >-
                    Unique identifier of the original video generation task.
                    Must be a valid task ID from a previously generated video.
                  example: ee603959-debb-48d1-98c4-a6d1c717eba6
                prompt:
                  type: string
                  description: >-
                    Descriptive text that guides the continuation of the video.
                    Explain what actions, movements, or developments should
                    happen next. Be specific but maintain consistency with the
                    original video content.
                  example: >-
                    The cat continues dancing with more energy and excitement,
                    spinning around with colorful light effects intensifying
                quality:
                  type: string
                  description: 'Video resolution, optional values are 720p or 1080p. '
                  example: 720p
                waterMark:
                  type: string
                  description: >-
                    Video watermark text content. An empty string indicates no
                    watermark, while a non-empty string will display the
                    specified text as a watermark in the bottom right corner of
                    the video.
                  example: apikley
                callBackUrl:
                  type: string
                  description: >-
                    The URL to receive AI video extension task completion
                    updates. Required for all video extension requests.


                    - System will POST task status and results to this URL when
                    video extension completes

                    - Callback includes extended video URLs, cover images, and
                    task information

                    - Your callback endpoint should accept POST requests with
                    JSON payload containing extension results

                    - For detailed callback format and implementation guide, see
                    [Video Extension
                    Callbacks](https://docs.apikley.ru/runway-api/extend-ai-video-callbacks)

                    - Alternatively, use the Get AI Video Details endpoint to
                    poll task status
                  example: https://api.example.com/callback
            example:
              taskId: ee603959-debb-48d1-98c4-a6d1c717eba6
              prompt: >-
                The cat continues dancing with more energy and excitement,
                spinning around with colorful light effects intensifying
              imageUrl: https://file.com/m/xxxxxxxx.png
              expandPrompt: true
              waterMark: apikley
              callBackUrl: https://api.example.com/callback
      responses:
        '200':
          description: Request successful
          content:
            application/json:
              schema:
                allOf:
                  - type: object
                    properties:
                      code:
                        type: integer
                        enum:
                          - 200
                          - 401
                          - 404
                          - 422
                          - 429
                          - 451
                          - 455
                          - 500
                        description: >-
                          Response status code


                          - **200**: Success - Request has been processed
                          successfully

                          - **401**: Unauthorized - Authentication credentials
                          are missing or invalid

                          - **404**: Not Found - The requested resource or
                          endpoint does not exist

                          - **422**: Validation Error - The request parameters
                          failed validation checks.The request parameters are
                          incorrect, please check the parameters.

                          - **429**: Rate Limited - Request limit has been
                          exceeded for this resource

                          - **451**: Unauthorized - Failed to fetch the image.
                          Kindly verify any access limits set by you or your
                          service provider.

                          - **455**: Service Unavailable - System is currently
                          undergoing maintenance

                          - **500**: Server Error - An unexpected error occurred
                          while processing the request
                      msg:
                        type: string
                        description: Status message
                        example: success
                      data:
                        type: object
                        properties:
                          taskId:
                            type: string
                            description: >-
                              Task ID for tracking task status. Use this ID with
                              the "Get AI Video Details" endpoint to query
                              extension task details and results.
                            example: 5c79****be8e
              example:
                code: 200
                msg: success
                data:
                  taskId: ee603959-debb-48d1-98c4-a6d1c717eba6
        '500':
          $ref: '#/components/responses/Error'
      callbacks:
        onVideoExtended:
          '{$request.body#/callBackUrl}':
            post:
              summary: Video Extension Completion Callback
              description: >-
                When video extension is complete, the system will send a POST
                request to the provided callback URL to notify the result
              requestBody:
                required: true
                content:
                  application/json:
                    schema:
                      type: object
                      required:
                        - code
                        - data
                        - msg
                      properties:
                        code:
                          type: integer
                          description: Status code, 200 indicates success
                          example: 200
                        msg:
                          type: string
                          description: Status message
                          example: All generated successfully.
                        data:
                          type: object
                          required:
                            - image_url
                            - task_id
                            - video_id
                            - video_url
                          properties:
                            image_url:
                              type: string
                              description: Cover image URL of the generated video
                              example: https://file.com/m/xxxxxxxx.png
                            task_id:
                              type: string
                              description: Task ID
                              example: ee603959-debb-48d1-98c4-a6d1c717eba6
                            video_id:
                              type: string
                              description: Video ID
                              example: 485da89c-7fca-4340-8c04-101025b2ae71
                            video_url:
                              type: string
                              description: Accessible video URL, valid for 14 days
                              example: https://file.com/k/xxxxxxx.mp4
              responses:
                '200':
                  description: Callback received successfully
                  content:
                    application/json:
                      schema:
                        allOf:
                          - type: object
                            properties:
                              code:
                                type: integer
                                enum:
                                  - 200
                                  - 400
                                  - 500
                                description: >-
                                  Response status code


                                  - **200**: Success - Request has been
                                  processed successfully

                                  - **400**: Get image info failed.

                                  Inappropriate content detected. Please replace
                                  the image or video.

                                  Incorrect image format.

                                  Please try again later. You can upgrade to
                                  Standard membership to start generating now.

                                  Reached the limit for concurrent generations.

                                  Unsupported width or height. Please adjust the
                                  size and try again.

                                  Upload failed due to network reasons, please
                                  re-enter.

                                  Your prompt was caught by our AI moderator. 
                                  Please adjust it and try again!

                                  Your prompt/negative prompt cannot exceed 2048
                                  characters. Please check if your input is too
                                  long.

                                  Your video creation prompt contains NSFW
                                  content, which isn't allowed under our policy.
                                  Kindly revise your prompt and generate again.

                                  - **500**: Server Error - An unexpected error
                                  occurred while processing the request
                              msg:
                                type: string
                                description: Error message when code != 200
                                example: success
                      example:
                        code: 200
                        msg: success
components:
  responses:
    Error:
      description: Server Error
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key
      description: >-
        All APIs require authentication via Bearer Token.


        Get API Key:

        1. Visit [API Key Management Page](https://app.apikley.ru/keys) to get your
        API Key


        Usage:

        Add to request header:

        Authorization: Bearer APIKLEY_API_KEY


        Note:

        - Keep your API Key secure and do not share it with others

        - If you suspect your API Key has been compromised, reset it immediately
        in the management page


To find navigation and other pages in this documentation, fetch the llms.txt file at: https://docs.apikley.ru/llms.txt