Runway Video Extension

POST

/api/v1/client/tasks

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

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

Callbacks

onVideoExtended

Request

Authorization

Bearer Token

Provide your bearer token in the

Authorization

header when making requests to protected resources.

Example:

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

Body Params application/jsonRequired

Examples

Responses

🟢200

application/json

Request successful

Bodyapplication/json

🔴500Error

Request Example

Shell

JavaScript

Java

Swift

curl --location 'https://api.emix.ai/api/v1/client/tasks' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
    "model": "runway/extend-ai-video",
    "callBackUrl": "https://api.example.com/callback",
    "input": {
        "task_id": "efb26d5fc51bc82fb9e54648f3f4e348",
  "prompt": "cat",
  "quality": "720p",
        "water_mark": "emix.ai"
    }
}'

Response Example

200 - Successful Example

{
    "code": 200,
    "msg": "success",
    "data": {
        "taskId": "ee603959-debb-48d1-98c4-a6d1c717eba6"
    }
}

Runway Text To Video

HappyHorse - text-to-video