HappyHorse Image-to-Video API Reference

HappyHorse-1.1-i2v Image-to-Video API reference and online debugging: generate video from a first-frame image (no audio-driven support), DashScope async passthrough endpoint.

POST /wan/api/v1/services/aigc/video-generation/video-synthesis

Image-to-Video: create a video generation task from a first-frame image

cURL

curl --request POST \
  --url https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'X-DashScope-Async: <x-dashscope-async>' \
  --data '
{
  "model": "happyhorse-1.1-i2v",
  "input": {
    "prompt": "A cat running across a meadow, bright sunshine, camera following",
    "media": [
      {
        "type": "first_frame",
        "url": "https://your-cdn.com/cat.png"
      }
    ]
  }
}
'

import requests

url = "https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis"

payload = {
    "model": "happyhorse-1.1-i2v",
    "input": {
        "prompt": "A cat running across a meadow, bright sunshine, camera following",
        "media": [
            {
                "type": "first_frame",
                "url": "https://your-cdn.com/cat.png"
            }
        ]
    }
}
headers = {
    "X-DashScope-Async": "<x-dashscope-async>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'X-DashScope-Async': '<x-dashscope-async>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'happyhorse-1.1-i2v',
    input: {
      prompt: 'A cat running across a meadow, bright sunshine, camera following',
      media: [{type: 'first_frame', url: 'https://your-cdn.com/cat.png'}]
    }
  })
};

fetch('https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'model' => 'happyhorse-1.1-i2v',
    'input' => [
        'prompt' => 'A cat running across a meadow, bright sunshine, camera following',
        'media' => [
                [
                                'type' => 'first_frame',
                                'url' => 'https://your-cdn.com/cat.png'
                ]
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json",
    "X-DashScope-Async: <x-dashscope-async>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis"

	payload := strings.NewReader("{\n  \"model\": \"happyhorse-1.1-i2v\",\n  \"input\": {\n    \"prompt\": \"A cat running across a meadow, bright sunshine, camera following\",\n    \"media\": [\n      {\n        \"type\": \"first_frame\",\n        \"url\": \"https://your-cdn.com/cat.png\"\n      }\n    ]\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-DashScope-Async", "<x-dashscope-async>")
	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis")
  .header("X-DashScope-Async", "<x-dashscope-async>")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"model\": \"happyhorse-1.1-i2v\",\n  \"input\": {\n    \"prompt\": \"A cat running across a meadow, bright sunshine, camera following\",\n    \"media\": [\n      {\n        \"type\": \"first_frame\",\n        \"url\": \"https://your-cdn.com/cat.png\"\n      }\n    ]\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-DashScope-Async"] = '<x-dashscope-async>'
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"model\": \"happyhorse-1.1-i2v\",\n  \"input\": {\n    \"prompt\": \"A cat running across a meadow, bright sunshine, camera following\",\n    \"media\": [\n      {\n        \"type\": \"first_frame\",\n        \"url\": \"https://your-cdn.com/cat.png\"\n      }\n    ]\n  }\n}"

response = http.request(request)
puts response.read_body

200

{
  "output": {
    "task_id": "hh-...",
    "task_status": "PENDING"
  },
  "request_id": "..."
}

You can debug directly in the Playground on the right: fill in Authorization with Bearer sk-your-api-key, set model / input.media / parameters, then send the request. A successful submission returns a task_id; see below for polling and downloading.

This page covers the create endpoint for happyhorse-1.1-i2v (Image-to-Video): give a first-frame image + prompt to bring the scene to life. For the complete async flow, see the HappyHorse Overview.

• HappyHorse’s i2v does not support driving_audio (audio-driven): it only accepts first_frame. For lip-sync / rap, use Wan2.7-i2v.
• input.media is required; otherwise the upstream reports Image-to-video model ... must provide an image. The media url must be a public https link that can be fetched directly via GET.
• The create request goes to /wan/api/v1/... with X-DashScope-Async: enable; do not use /v1/videos.

Code Examples

cURL

curl -X POST "https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis" \
  -H "X-DashScope-Async: enable" \
  -H "Authorization: Bearer sk-your-api-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse-1.1-i2v",
    "input": {
      "prompt": "A cat running across a meadow, bright sunshine, camera following",
      "media": [
        {"type": "first_frame", "url": "https://your-cdn.com/cat.png"}
      ]
    },
    "parameters": {"resolution": "720P", "duration": 5, "prompt_extend": true, "watermark": true}
  }'

import requests

url = "https://api.apiyi.com/wan/api/v1/services/aigc/video-generation/video-synthesis"
headers = {
    "Authorization": "Bearer sk-your-api-key",
    "Content-Type": "application/json",
    "X-DashScope-Async": "enable",
}
body = {
    "model": "happyhorse-1.1-i2v",
    "input": {
        "prompt": "A cat running across a meadow, bright sunshine, camera following",
        "media": [{"type": "first_frame", "url": "https://your-cdn.com/cat.png"}],
    },
    "parameters": {"resolution": "720P", "duration": 5, "prompt_extend": True, "watermark": True},
}
resp = requests.post(url, json=body, headers=headers, timeout=30)
print("task_id:", resp.json()["output"]["task_id"])

Parameter and Media Quick Reference

Parameter	Type	Required	Default	Notes
model	string	✓	—	Fixed to happyhorse-1.1-i2v
input.prompt	string	✓	—	Text prompt
input.media	array	✓	—	See the media table below
parameters.resolution	string		720P	720P / 1080P
parameters.duration	int		5	Integer of 2–15 seconds
parameters.prompt_extend	bool		true	Smart rewriting, recommended on
parameters.watermark	bool		false	”AI Generated” watermark

media[] Values

type	Required	Count	Notes
first_frame	✓	1	First-frame image; the video starts from this image (HappyHorse i2v supports only this)

Response Format

{
  "output": { "task_id": "...", "task_status": "PENDING" },
  "request_id": "..."
}

After submission, poll GET /v1/tasks/{task_id} until completed, then download the mp4 from result_url (without the Authorization header, expires in 24 hours). See the full polling loop in HappyHorse Overview · Async Call Flow.

Authorizations

Authorization · string · header · required

The API Key obtained from the APIYI Console

Headers

X-DashScope-Async · enum<string> · default: enable · required

Async processing switch, must be set to enable

Available options: enable

Body

application/json

model · enum<string> · default: happyhorse-1.1-i2v · required

Model ID, fixed to happyhorse-1.1-i2v for Image-to-Video

Available options: happyhorse-1.1-i2v

input · object · required

Show child attributes

parameters · object

Show child attributes

Response

200

application/json

Task submitted, returns task_id and PENDING status

output · object

Show child attributes

request_id · string

Unique request identifier

Example:

"..."