> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apipod.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Seedance 2.5 Video Extend
> Seedance 2.5 Video Extend pins the omni-reference task type to video extension: provide the source video, describe the forward or backward continuation, and the output aspect ratio automatically follows the source video.
At least one reference video (the source video to extend) is required.
## Extension Constraints
Seedance 2.5 Video Extend is the video-extension sub-task of the omni-reference family on the official discount route. Sending the source video plus explicit continuation wording pins `omni_reference_task_type=extend` upstream, so the provider validates the constraints at submission time and rejects incompatible parameters immediately with a 400, instead of failing asynchronously minutes later.
* **Source video**: at least one reference video is required.
* **Duration**: 4-30 seconds (default 4), covering the extension length.
* **Aspect ratio**: not settable. The output keeps the source video aspect ratio; the field is not part of the contract and any passed value is silently ignored (adaptive is always sent).
* **Reference materials**: up to 30 images, 10 videos, and 10 audios; audio cannot be provided on its own.
* **Prompt wording**: use explicit continuation wording such as extend the video forward or continue the story backward, and address materials explicitly with `@视频N` / `@图N` tokens (for example, `延长@视频1`). Ambiguous extend-or-edit intents may still be re-judged by the model.
Note: When video input is enabled, the unit price is lower because the billing formula differs: without video = unit price × output duration; with video = unit price × (input duration + output duration).
Want to edit a video in place instead? Use [Seedance 2.5 Video Edit](/seedance/2-5-video-edit).
## OpenAPI
````yaml api-reference/openapi/seedance--2-5-video-extend.yaml POST /v1/videos/generations
openapi: 3.1.0
info:
title: Seedance 2.5 Video Extend API
version: 1.0.0
description: >-
Seedance 2.5 Video Extend pins the upstream omni-reference task type to
video extension. Provide the source video and describe the continuation
(forward or backward); the output is 4-30 seconds, the aspect ratio
automatically follows the source video (not settable - the field is not
exposed and any passed value is ignored), and the required source video is
validated at submission time instead of failing asynchronously. In APIPod,
the public model ID is seedance-2.5-extend, and results are returned through
asynchronous video tasks.
servers:
- url: https://api.apipod.ai
description: Production
security: []
paths:
/v1/videos/generations:
post:
tags:
- Seedance 2.5 Video Extend
summary: Create Generation Task
description: >-
Seedance 2.5 Video Extend pins the upstream omni-reference task type to
video extension. Provide the source video and describe the continuation
(forward or backward); the output is 4-30 seconds, the aspect ratio
automatically follows the source video (not settable - the field is not
exposed and any passed value is ignored), and the required source video
is validated at submission time instead of failing asynchronously. In
APIPod, the public model ID is seedance-2.5-extend, and results are
returned through asynchronous video tasks.
operationId: create-seedance-2-5-video-extend
requestBody:
required: true
content:
application/json:
schema:
type: object
title: Seedance 2.5 Video Extend
properties:
model:
type: string
title: Model ID
description: Public APIPod model ID.
const: seedance-2.5-extend
prompt:
type: string
title: Prompt
description: >-
Continuation instructions, up to 30000 characters. Use
explicit extension wording such as extend the video forward
or continue the story backward, and address materials
explicitly with @视频N / @图N tokens (for example, 延长@视频1). It
is recommended to keep the prompt to no more than 500
Chinese characters or 1,000 English words.
maxLength: 30000
image_urls:
type: array
title: Image Urls
description: >-
Optional reference image URLs (for example the character or
style to keep). Up to 30 images are supported; each image
must be smaller than 30 MB.
maxItems: 30
items:
type: string
video_urls:
type: array
title: Video Urls
description: >-
Reference video URLs. At least one is required (the source
video to extend); up to 10 videos are supported.
minItems: 1
maxItems: 10
items:
type: string
audio_urls:
type: array
title: Audio Urls
description: >-
Optional reference audio URLs. Up to 10 audios are
supported; each audio lasts 2-30 seconds. Audio cannot be
provided on its own.
maxItems: 10
items:
type: string
duration:
type: integer
title: Duration
description: Output video duration in seconds, from 4 to 30.
enum:
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
default: 4
minimum: 4
maximum: 30
resolution:
type: string
title: Resolution
description: Generate video resolution.
enum:
- 480p
- 720p
- 1080p
default: 720p
generate_audio:
type: boolean
title: Generate Audio
description: >-
Controls whether the generated video contains audio
synchronized with the visuals.
default: true
required:
- model
- prompt
- video_urls
example:
model: seedance-2.5-extend
prompt: 延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内
video_urls:
- >-
https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov
- >-
https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4
- >-
https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4
duration: 11
resolution: 480p
web_search: false
generate_audio: true
responses:
'200':
description: Task accepted
content:
application/json:
schema:
type: object
title: Task Submit Response
description: Standard response for task submission
properties:
code:
type: integer
data:
type: object
title: Task Submit Data
description: Data content for task submission
properties:
task_id:
type: string
description: generatation task id
message:
type: string
required:
- code
- message
- data
example:
code: 200
message: success
data:
task_id: vid_task_01JEXAMPLE
security:
- bearerAuth: []
x-codeSamples:
- lang: Shell
label: cURL
source: |-
curl https://api.apipod.ai/v1/videos/generations \
-H "Authorization: Bearer $APIPOD_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "seedance-2.5-extend",
"prompt": "延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内",
"video_urls": ["https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4"],
"duration": 11,
"resolution": "480p",
"web_search": false,
"generate_audio": true
}'
- lang: Python
label: Python
source: |-
import os
import requests
payload = {
"model": "seedance-2.5-extend",
"prompt": "延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内",
"video_urls": ["https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4"],
"duration": 11,
"resolution": "480p",
"web_search": False,
"generate_audio": True
}
response = requests.post(
"https://api.apipod.ai/v1/videos/generations",
headers={
"Authorization": f"Bearer {os.environ['APIPOD_API_KEY']}",
"Content-Type": "application/json",
},
json=payload,
timeout=60,
)
response.raise_for_status()
print(response.json())
- lang: Go
label: Go
source: |-
package main
import (
"bytes"
"encoding/json"
"fmt"
"net/http"
"os"
)
func main() {
payload := map[string]any{}
if err := json.Unmarshal([]byte(`{
"model": "seedance-2.5-extend",
"prompt": "延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内",
"video_urls": ["https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4"],
"duration": 11,
"resolution": "480p",
"web_search": false,
"generate_audio": true
}`), &payload); err != nil {
panic(err)
}
body, err := json.Marshal(payload)
if err != nil {
panic(err)
}
req, err := http.NewRequest(http.MethodPost, "https://api.apipod.ai/v1/videos/generations", bytes.NewReader(body))
if err != nil {
panic(err)
}
req.Header.Set("Authorization", "Bearer "+os.Getenv("APIPOD_API_KEY"))
req.Header.Set("Content-Type", "application/json")
resp, err := http.DefaultClient.Do(req)
if err != nil {
panic(err)
}
defer resp.Body.Close()
fmt.Println(resp.Status)
}
- lang: Rust
label: Rust
source: |-
use reqwest::Client;
use serde_json::json;
use std::env;
#[tokio::main]
async fn main() -> Result<(), Box> {
let payload = json!({
"model": "seedance-2.5-extend",
"prompt": "延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内",
"video_urls": ["https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4"],
"duration": 11,
"resolution": "480p",
"web_search": false,
"generate_audio": true
});
let response = Client::new()
.post("https://api.apipod.ai/v1/videos/generations")
.bearer_auth(env::var("APIPOD_API_KEY")?)
.json(&payload)
.send()
.await?
.error_for_status()?;
println!("{}", response.text().await?);
Ok(())
}
- lang: JavaScript
label: JavaScript
source: >-
const response = await
fetch("https://api.apipod.ai/v1/videos/generations", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.APIPOD_API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify(
{
"model": "seedance-2.5-extend",
"prompt": "延长@视频1，窗户打开后进入@视频2的美术馆室内，最后镜头进入@视频3的画内",
"video_urls": ["https://arkdocs.tos-cn-beijing.volces.com/videos/video-generation/r2v_extend_video1_75.mov", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video2.mp4", "https://ark-project.tos-cn-beijing.volces.com/doc_video/r2v_extend_video3.mp4"],
"duration": 11,
"resolution": "480p",
"web_search": false,
"generate_audio": true
}
),
});
if (!response.ok) {
throw new Error(`APIPod request failed: ${response.status} ${await response.text()}`);
}
console.log(await response.json());
components:
securitySchemes:
bearerAuth:
type: http
scheme: bearer
bearerFormat: APIPod API key
description: Use your APIPod API key as a Bearer token in the Authorization header.
````