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API Documentation
API Reference
Videos
Generate Video

Generate Video

Loading models...
H
HappyHorse-1.0-R2V (happyhorse-1.0-r2v)
happyhorse-1.0-r2v0 models support this endpoint

HappyHorse-1.0-R2V supports Reference-to-Video generation, offering enhanced stability in subject and scene referencing. Capable of processing up to 9 reference images, it precisely preserves creative intent to deliver superior performance. https://bailian.console.alibabacloud.com/cn-beijing?tab=model#/model-market/detail/happyhorse-1.0-r2v?serviceSite=asia-pacific-china

Generate video

https://api.modelstream.ai
POST/v1/video/generations

Authentication

BearerAuth
AuthenticationBearer <token>

All API requests must be authenticated using a Bearer token in the Authorization header. Please ensure your API key is active.Authorization: Bearer sk-xxxxxx

Parameter Location: Header Param

Request Body

application/json

These parameters come from the selected model form_schema. Switching models updates this list and the request example.

images*array

Required. Upload 1-9 reference images and reference them in order with [Image 1], [Image 2]... in the prompt. Supports JPEG, JPG, PNG, WEBP; short edge ≥400px (720P+ recommended), each image ≤20MB.

RequiredExample Value: ["https://static.modelstream.ai/demo/happyhorse/happyhorse-1.0-r2v_Reference.png","https://help-static-aliyun-doc.aliyuncs.com/file-manage-files/zh-CN/20260424/fvuihk/hh-v2v2-folding-fan.jpg","https://help-static-aliyun-doc.aliyuncs.com/file-manage-files/zh-CN/20260424/imerii/hh-v2v-earrings.jpg"]Value Range: 1 ≤ value ≤ 9
prompt*string

Required. Describe the actions and scene details of the reference subjects; reference images in order with [Image 1], [Image 2].... Up to 2500 Chinese characters or 5000 non-Chinese characters.

RequiredExample Value: The woman in a red cheongsam from [Image 1] gracefully sways her tassel earrings from [Image 3] as she turns her head while unfolding a folding fan from [Image 2], exuding an oriental charm.Placeholder: Describe the actions of the reference subjects in the scene, referencing with [Image 1]...
ratio?string

Video aspect ratio; options 16:9, 9:16, 1:1, 4:3, 3:4, 4:5, 5:4, 21:9, 9:21. Default 16:9.

Example Value: 16:9
Enum/Options:
16:99:161:14:33:44:55:421:99:21
resolution?string

Video output resolution; options 720P, 1080P, default 1080P.

Example Value: 1080P
Enum/Options:
1080P720P
duration?number

Video duration in seconds; range 3-15 seconds, default 5.

Example Value: 5Value Range: 3 ≤ value ≤ 15step: 1
watermark?boolean

Whether to add the "Happy Horse" watermark to the bottom-right of the video. Enabled by default.

Example Value: true
seed?number

Random seed, range [0, 2147483647]. A fixed integer improves reproducibility; leave empty for a random seed.

Placeholder: Empty for randomValue Range: 0 ≤ value ≤ 2147483647

Response Parameters

application/json
200apiDocs.responses.successCreateVideoGenTask
task_id?string

Parameter description for Task Id

status?string

Parameter description for Status

400apiDocs.responses.badRequestParams
error?object

Parameter description for Error

message?string

Error Message

type?string

Error Type

param?string

Related Parameters

code?string

Error Code

curl -X POST "https://api.modelstream.ai/v1/video/generations" \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "happyhorse-1.0-r2v",
  "prompt": "The woman in a red cheongsam from [Image 1] gracefully sways her tassel earrings from [Image 3] as she turns her head while unfolding a folding fan from [Image 2], exuding an oriental charm.",
  "size": "1080P",
  "duration": 5,
  "metadata": {
    "input": {
      "media": [
        {
          "type": "reference_image",
          "url": "https://static.modelstream.ai/demo/happyhorse/happyhorse-1.0-r2v_Reference.png"
        },
        {
          "type": "reference_image",
          "url": "https://help-static-aliyun-doc.aliyuncs.com/file-manage-files/zh-CN/20260424/fvuihk/hh-v2v2-folding-fan.jpg"
        },
        {
          "type": "reference_image",
          "url": "https://help-static-aliyun-doc.aliyuncs.com/file-manage-files/zh-CN/20260424/imerii/hh-v2v-earrings.jpg"
        }
      ]
    },
    "parameters": {
      "ratio": "16:9",
      "watermark": true
    }
  }
}'
{
  "task_id": "abcd1234efgh",
  "status": "queued"
}