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Access Notice SD2.0 is not yet available to all users. Contact LaoZhang API support to request access: Telegram @laozhang_cn. Base URL: https://api.yelinai.com Required endpoints: 2
  1. POST /v1/video/generations: create a video generation task
  2. GET /v1/video/generations/{task_id}: query task status and get the result URL

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API Flow

SD2.0 video generation is an asynchronous task API. Create a task first, poll the task by task_id, then download the video after the task completes.
  1. Create task
Call POST /v1/video/generations with the model, prompt, video parameters, and optional reference files.
  1. Poll status
Call GET /v1/video/generations/{task_id} and check status.
  1. Download video
When status=completed, read the video URL from the response and download the mp4. Common status progression: 
pending -> running -> succeeded -> completed
Failed tasks usually return failed with an error field.

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Models

ModelDescriptionRecommended use
seedance-2.0SD2.0 Video GenerationVideo generation, image reference, video reference

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Create Task

POST /v1/video/generations Create an SD2.0 video generation task.

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Headers

HeaderRequiredDescription
AuthorizationYesBearer $API_KEY
Content-TypeYesmultipart/form-data

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Request Parameters

ParameterTypeRequiredDescription
modelstringYesModel ID, fixed as seedance-2.0
promptstringYesVideo generation prompt, supports referencing uploaded files
durationintegerNoOutput duration in seconds, default 5 seconds
aspect_ratiostringNoOutput aspect ratio, e.g., 16:9, 9:16, 1:1, default 16:9
filesfileNoReference files, supports images (jpg/png) and videos (mp4)
first_frame_imagefileNoFirst frame image file, specifies the opening scene
last_frame_imagefileNoLast frame image file, specifies the ending scene

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File Reference Syntax

Reference files by upload order in the prompt:
ReferenceMeaning
@IMG_1First uploaded image file
@IMG_2Second uploaded image file
@VID_1First uploaded video file
@VID_2Second uploaded video file

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Text-to-video Example

curl -X POST https://api.yelinai.com/v1/video/generations \
  -H "Authorization: Bearer $API_KEY" \
  -F "model=seedance-2.0" \
  -F "prompt=Cute cat playing on grass under sunny sky" \
  -F "duration=5" \
  -F "aspect_ratio=16:9"

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Image Reference Example

curl -X POST https://api.yelinai.com/v1/video/generations \
  -H "Authorization: Bearer $API_KEY" \
  -F "model=seedance-2.0" \
  -F "prompt=@IMG_1 person walking on beach" \
  -F "duration=5" \
  -F "aspect_ratio=16:9" \
  -F "files=@/path/to/image1.jpg"

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Multi-asset Reference Example

curl -X POST https://api.yelinai.com/v1/video/generations \
  -H "Authorization: Bearer $API_KEY" \
  -F "model=seedance-2.0" \
  -F "prompt=@IMG_1 and @IMG_3 dancing with person from @VID_1" \
  -F "duration=5" \
  -F "aspect_ratio=16:9" \
  -F "files=@/path/to/image1.jpg" \
  -F "files=@/path/to/image2.jpg" \
  -F "files=@/path/to/video1.mp4"

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First/Last Frame Control Example

curl -X POST https://api.yelinai.com/v1/video/generations \
  -H "Authorization: Bearer $API_KEY" \
  -F "model=seedance-2.0" \
  -F "prompt=A person walking from room to outdoor scene" \
  -F "duration=8" \
  -F "aspect_ratio=16:9" \
  -F "first_frame_image=@/path/to/first_frame.jpg" \
  -F "last_frame_image=@/path/to/last_frame.jpg"

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Create Response

{
  "task_id": "task-20260501120000-abc123",
  "status": "pending",
  "created_at": "2026-05-01T12:00:00Z"
}
Response fields:
FieldTypeDescription
task_idstringTask ID used for status polling
statusstringInitial status, commonly pending
created_atstringCreation time (ISO format)

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Query Task

GET /v1/video/generations/{task_id} Query the status of a video generation task. 
curl https://api.yelinai.com/v1/video/generations/task-20260501120000-abc123 \
  -H "Authorization: Bearer $API_KEY"

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Path Parameters

ParameterTypeRequiredDescription
task_idstringYesThe task_id returned by the create task response

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Query Response

In progress: 
{
  "task_id": "task-20260501120000-abc123",
  "status": "running",
  "progress": 50,
  "created_at": "2026-05-01T12:00:00Z",
  "updated_at": "2026-05-01T12:01:00Z"
}
Completed: 
{
  "task_id": "task-20260501120000-abc123",
  "status": "completed",
  "video_url": "https://example.com/generated-video.mp4",
  "created_at": "2026-05-01T12:00:00Z",
  "updated_at": "2026-05-01T12:05:00Z"
}
Failed: 
{
  "task_id": "task-20260501120000-abc123",
  "status": "failed",
  "error": {
    "code": "GENERATION_FAILED",
    "message": "Video generation failed"
  },
  "created_at": "2026-05-01T12:00:00Z",
  "updated_at": "2026-05-01T12:03:00Z"
}
Response fields:
FieldTypeDescription
task_idstringTask ID
statusstringpending, running, succeeded, completed, failed
progressintegerTask progress (0-100)
video_urlstringVideo URL returned after completion
created_atstringCreation time
updated_atstringUpdate time
errorobjectError details for failed tasks

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Download Video

After the query response returns completed, read video_url and download it directly: 
curl -L "$VIDEO_URL" -o output.mp4
video_url is usually a temporary signed URL. Download it immediately or copy it to your own object storage.

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Full Python Example

import os
import time
import requests

API_KEY = os.environ["API_KEY"]
BASE_URL = "https://api.yelinai.com/v1/video/generations"

headers = {
    "Authorization": f"Bearer {API_KEY}",
}

files = {
    "model": (None, "seedance-2.0"),
    "prompt": (None, "@IMG_1 person walking on beach"),
    "duration": (None, "5"),
    "aspect_ratio": (None, "16:9"),
    "files": open("/path/to/image.jpg", "rb"),
}

create_resp = requests.post(BASE_URL, headers=headers, files=files, timeout=60)
create_resp.raise_for_status()
task_id = create_resp.json()["task_id"]

while True:
    query_resp = requests.get(f"{BASE_URL}/{task_id}", headers=headers, timeout=60)
    query_resp.raise_for_status()
    task = query_resp.json()
    status = task.get("status")

    if status == "completed":
        video_url = task.get("video_url")
        video_resp = requests.get(video_url, timeout=120)
        video_resp.raise_for_status()
        with open(f"{task_id}.mp4", "wb") as f:
            f.write(video_resp.content)
        break

    if status == "failed":
        raise RuntimeError(task.get("error") or task)

    time.sleep(20)

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FAQ

What are the file upload limitations? Currently supports jpg, png image formats and mp4 video format. Individual file size should not exceed 50MB. How to correctly reference uploaded files? By upload order, use @IMG_1, @IMG_2 for images, and @VID_1, @VID_2 for videos. How long does a task take to complete? Typically 30-120 seconds depending on video duration and server load. Recommended polling interval is 20-30 seconds.