> ## Documentation Index
> Fetch the complete documentation index at: https://docs.aireiter.com/llms.txt
> Use this file to discover all available pages before exploring further.

# HappyHorse 1.0 Video Generation and Editing

> - Supports text-to-video, image-to-video, multi-reference image-to-video, and video editing
- Supports 720p / 1080p output and 3-15 second video generation
- Text-to-video and multi-reference image-to-video support 9 aspect ratios
- Asynchronous processing mode returns a task ID for later query


export const apiKeyUrl = 'https://aireiter.com/keys';

<Note>
  The model name of HappyHorse 1.0 in AIReiter is `happyhorse_1_0`.
</Note>

## Authorizations

<ParamField header="Authorization" type="string" required>
  All endpoints require Bearer Token authentication.

  Visit the <a href={apiKeyUrl} target="_blank">API Key management page</a> to get your API Key, and add the following to the request header:

  ```
  Authorization: Bearer YOUR_API_KEY
  ```
</ParamField>

## Body

<ParamField body="model" type="string" required>
  Model name, fixed to `happyhorse_1_0`.
</ParamField>

<ParamField body="params" type="object" required>
  Model parameters object.

  <Expandable title="Properties of the params Object">
    <ParamField body="type" type="string" default="text_to_video" required>
      Video workflow:

      * `text_to_video` - Generate a video based on text
      * `image_to_video` - Generate a video using a first-frame image
      * `reference_to_video` - Generate a video using 1-9 reference images
      * `video_edit` - Edit a source video based on instructions
    </ParamField>

    <ParamField body="prompt" type="string">
      Video content description or editing instructions. Required for `text_to_video`, `reference_to_video`, and `video_edit`, optional for `image_to_video`.

      Supports up to 2500 Chinese characters or 5000 non-Chinese characters; any excess will be truncated.

      In `reference_to_video` mode, use the names `character1`, `character2`, and so on to refer to reference images in image order.
    </ParamField>

    <ParamField body="image_url" type="string | string[]">
      Image URL, must be directly accessible from the public internet.

      * `image_to_video` - Required, use the first image as the first frame
      * `reference_to_video` - Required, supports 1-9 ordered reference images
      * `video_edit` - Optional, up to 5 style or subject reference images

      Supports JPEG, JPG, PNG, and WEBP. For image-to-video and video editing, images must have both width and height of at least 300px; for multi-reference image mode, the shorter side must be at least 400px. A single image must not exceed 10MB.
    </ParamField>

    <ParamField body="video_url" type="string | string[]">
      Required for `video_edit` mode, only one source video is used.

      Supports MP4 and MOV, and H.264 encoding is recommended. Source video requirements:

      * Duration: 3-60 seconds; if it exceeds 15 seconds, only the first 15 seconds will be processed
      * File size must not exceed 100MB
      * The longer side must not exceed 2160px, and the shorter side must be at least 320px
      * Aspect ratio must be between 1:2.5 and 2.5:1
      * Frame rate must be greater than 8 FPS
    </ParamField>

    <ParamField body="resolution" type="string" default="720p">
      Output resolution: `720p` or `1080p`.
    </ParamField>

    <ParamField body="aspect_ratio" type="string" default="16:9">
      Output aspect ratio for `text_to_video` and `reference_to_video` modes.

      Supported: `16:9`, `9:16`, `1:1`, `4:3`, `3:4`, `4:5`, `5:4`, `9:21`, `21:9`.

      <Warning>`video_edit` does not support this parameter. Do not pass it. The output aspect ratio of `image_to_video` follows the input image.</Warning>
    </ParamField>

    <ParamField body="video_length" type="integer" default="5">
      Output video duration, in seconds. Supports integers between 3 and 15.

      <Warning>`video_edit` does not support this parameter. Do not pass it. The output duration is automatically determined by the source video, equal to `min(input video duration, 15 seconds)`.</Warning>
    </ParamField>

    <ParamField body="seed" type="integer" default="0">
      Random seed, in the range 0-2147483647. When `0` is passed or omitted, a random seed is used.
    </ParamField>

    <ParamField body="keep_original_sound" type="boolean" default="false">
      Valid only for `video_edit` mode. When set to `true`, the source video audio track is forcibly preserved; when set to `false` or omitted, the model decides automatically.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="out_task_id" type="string" required>
  A unique task ID generated by the caller, used later to query task status and results.

  Only letters, numbers, underscores, and hyphens are supported, with a length of 1-64 characters.
</ParamField>

## Response

<ResponseField name="out_task_id" type="string">
  Caller task ID, can be used to query results.
</ResponseField>

<ResponseField name="status" type="string">
  Initial status, usually `pending`.
</ResponseField>

<ResponseField name="created_at" type="string">
  Creation time, in ISO 8601 format.
</ResponseField>

## Query Task

After the task is submitted successfully, query its status using the same `out_task_id`. Task statuses include `pending`, `processing`, `completed`, and `failed`; after completion, the `output` array contains the video result.

```bash theme={null}
curl --request POST \
  --url https://aireiter.com/api/openapi/query \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
    "out_task_id": "happyhorse_1_0_task_123456"
  }'
```

## Request Examples

<RequestExample>
  ```bash cURL (text to video) theme={null}
  curl --request POST \
    --url https://aireiter.com/api/openapi/submit \
    --header 'Authorization: Bearer <token>' \
    --header 'Content-Type: application/json' \
    --data '{
      "model": "happyhorse_1_0",
      "params": {
        "type": "text_to_video",
        "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
        "resolution": "720p",
        "aspect_ratio": "16:9",
        "video_length": 5,
        "seed": 0
      },
      "out_task_id": "happyhorse_1_0_t2v_123456"
    }'
  ```

  ```bash cURL (image to video) theme={null}
  curl --request POST \
    --url https://aireiter.com/api/openapi/submit \
    --header 'Authorization: Bearer <token>' \
    --header 'Content-Type: application/json' \
    --data '{
      "model": "happyhorse_1_0",
      "params": {
        "type": "image_to_video",
        "prompt": "Make the cat in the image run naturally across the grass, with the camera smoothly following",
        "image_url": ["https://example.com/cat.png"],
        "resolution": "720p",
        "video_length": 5
      },
      "out_task_id": "happyhorse_1_0_i2v_123456"
    }'
  ```

  ```bash cURL (multi-reference image to video) theme={null}
  curl --request POST \
    --url https://aireiter.com/api/openapi/submit \
    --header 'Authorization: Bearer <token>' \
    --header 'Content-Type: application/json' \
    --data '{
      "model": "happyhorse_1_0",
      "params": {
        "type": "reference_to_video",
        "prompt": "character1 walks into character2's scene and picks up the prop in character3, maintaining a smooth 3D cartoon style",
        "image_url": [
          "https://example.com/character.jpg",
          "https://example.com/scene.jpg",
          "https://example.com/prop.jpg"
        ],
        "resolution": "1080p",
        "aspect_ratio": "16:9",
        "video_length": 8
      },
      "out_task_id": "happyhorse_1_0_r2v_123456"
    }'
  ```

  ```bash cURL (video editing) theme={null}
  curl --request POST \
    --url https://aireiter.com/api/openapi/submit \
    --header 'Authorization: Bearer <token>' \
    --header 'Content-Type: application/json' \
    --data '{
      "model": "happyhorse_1_0",
      "params": {
        "type": "video_edit",
        "prompt": "Change the red paper airplane in the video to blue, while preserving the original background and camera motion",
        "video_url": ["https://example.com/source.mp4"],
        "image_url": ["https://example.com/blue-paper-plane.jpg"],
        "resolution": "720p",
        "keep_original_sound": true,
        "seed": 42
      },
      "out_task_id": "happyhorse_1_0_edit_123456"
    }'
  ```

  ```python Python theme={null}
  import requests

  url = "https://aireiter.com/api/openapi/submit"

  payload = {
      "model": "happyhorse_1_0",
      "params": {
          "type": "text_to_video",
          "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
          "resolution": "720p",
          "aspect_ratio": "16:9",
          "video_length": 5,
          "seed": 0
      },
      "out_task_id": "happyhorse_1_0_t2v_123456"
  }

  headers = {
      "Authorization": "Bearer <token>",
      "Content-Type": "application/json"
  }

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

  print(response.json())
  ```

  ```javascript JavaScript theme={null}
  const url = "https://aireiter.com/api/openapi/submit";

  const payload = {
    model: "happyhorse_1_0",
    params: {
      type: "text_to_video",
      prompt: "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
      resolution: "720p",
      aspect_ratio: "16:9",
      video_length: 5,
      seed: 0
    },
    out_task_id: "happyhorse_1_0_t2v_123456"
  };

  const headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
  };

  fetch(url, {
    method: "POST",
    headers: headers,
    body: JSON.stringify(payload)
  })
    .then(response => response.json())
    .then(data => console.log(data))
    .catch(error => console.error('Error:', error));
  ```

  ```go Go theme={null}
  package main

  import (
      "bytes"
      "encoding/json"
      "fmt"
      "io/ioutil"
      "net/http"
  )

  func main() {
      url := "https://aireiter.com/api/openapi/submit"

      payload := map[string]interface{}{
          "model": "happyhorse_1_0",
          "params": map[string]interface{}{
              "type": "text_to_video",
              "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
              "resolution": "720p",
              "aspect_ratio": "16:9",
              "video_length": 5,
              "seed": 0,
          },
          "out_task_id": "happyhorse_1_0_t2v_123456",
      }

      jsonData, _ := json.Marshal(payload)

      req, _ := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
      req.Header.Set("Authorization", "Bearer <token>")
      req.Header.Set("Content-Type", "application/json")

      client := &http.Client{}
      resp, err := client.Do(req)
      if err != nil {
          panic(err)
      }
      defer resp.Body.Close()

      body, _ := ioutil.ReadAll(resp.Body)
      fmt.Println(string(body))
  }
  ```

  ```java Java theme={null}
  import java.net.http.HttpClient;
  import java.net.http.HttpRequest;
  import java.net.http.HttpResponse;
  import java.net.URI;

  public class Main {
      public static void main(String[] args) throws Exception {
          String url = "https://aireiter.com/api/openapi/submit";

          String payload = """
              {
                "model": "happyhorse_1_0",
                "params": {
                  "type": "text_to_video",
                  "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
                  "resolution": "720p",
                  "aspect_ratio": "16:9",
                  "video_length": 5,
                  "seed": 0
                },
                "out_task_id": "happyhorse_1_0_t2v_123456"
              }
          """;

          HttpClient client = HttpClient.newHttpClient();
          HttpRequest request = HttpRequest.newBuilder()
              .uri(URI.create(url))
              .header("Authorization", "Bearer <token>")
              .header("Content-Type", "application/json")
              .POST(HttpRequest.BodyPublishers.ofString(payload))
              .build();

          HttpResponse<String> response = client.send(request,
              HttpResponse.BodyHandlers.ofString());

          System.out.println(response.body());
      }
  }
  ```

  ```php PHP theme={null}
  <?php

  $url = "https://aireiter.com/api/openapi/submit";

  $payload = [
      "model" => "happyhorse_1_0",
      "params" => [
          "type" => "text_to_video",
          "prompt" => "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
          "resolution" => "720p",
          "aspect_ratio" => "16:9",
          "video_length" => 5,
          "seed" => 0
      ],
      "out_task_id" => "happyhorse_1_0_t2v_123456"
  ];

  $ch = curl_init($url);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  curl_setopt($ch, CURLOPT_POST, true);
  curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($payload));
  curl_setopt($ch, CURLOPT_HTTPHEADER, [
      "Authorization: Bearer <token>",
      "Content-Type: application/json"
  ]);

  $response = curl_exec($ch);
  curl_close($ch);

  echo $response;
  ?>
  ```

  ```ruby Ruby theme={null}
  require 'net/http'
  require 'json'
  require 'uri'

  url = URI("https://aireiter.com/api/openapi/submit")

  payload = {
    model: "happyhorse_1_0",
    params: {
      type: "text_to_video",
      prompt: "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
      resolution: "720p",
      aspect_ratio: "16:9",
      video_length: 5,
      seed: 0
    },
    out_task_id: "happyhorse_1_0_t2v_123456"
  }

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

  request = Net::HTTP::Post.new(url)
  request["Authorization"] = "Bearer <token>"
  request["Content-Type"] = "application/json"
  request.body = payload.to_json

  response = http.request(request)
  puts response.body
  ```

  ```swift Swift theme={null}
  import Foundation

  let url = URL(string: "https://aireiter.com/api/openapi/submit")!

  let payload: [String: Any] = [
      "model": "happyhorse_1_0",
      "params": [
          "type": "text_to_video",
          "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
          "resolution": "720p",
          "aspect_ratio": "16:9",
          "video_length": 5,
          "seed": 0
      ],
      "out_task_id": "happyhorse_1_0_t2v_123456"
  ]

  var request = URLRequest(url: url)
  request.httpMethod = "POST"
  request.setValue("Bearer <token>", forHTTPHeaderField: "Authorization")
  request.setValue("application/json", forHTTPHeaderField: "Content-Type")
  request.httpBody = try? JSONSerialization.data(withJSONObject: payload)

  let task = URLSession.shared.dataTask(with: request) { data, response, error in
      if let error = error {
          print("Error: \(error)")
          return
      }

      if let data = data, let responseString = String(data: data, encoding: .utf8) {
          print(responseString)
      }
  }

  task.resume()
  ```

  ```csharp C# theme={null}
  using System;
  using System.Net.Http;
  using System.Text;
  using System.Threading.Tasks;

  class Program
  {
      static async Task Main(string[] args)
      {
          var url = "https://aireiter.com/api/openapi/submit";

          var payload = @"
                {
                    ""model"": ""happyhorse_1_0"",
                    ""params"": {
                        ""type"": ""text_to_video"",
                        ""prompt"": ""A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight"",
                        ""resolution"": ""720p"",
                        ""aspect_ratio"": ""16:9"",
                        ""video_length"": 5,
                        ""seed"": 0
                    },
                    ""out_task_id"": ""happyhorse_1_0_t2v_123456""
                }";

          using var client = new HttpClient();
          client.DefaultRequestHeaders.Add("Authorization", "Bearer <token>");

          var content = new StringContent(payload, Encoding.UTF8, "application/json");
          var response = await client.PostAsync(url, content);
          var result = await response.Content.ReadAsStringAsync();

          Console.WriteLine(result);
      }
  }
  ```

  ```c C theme={null}
  #include <stdio.h>
  #include <curl/curl.h>

  int main(void) {
      CURL *curl;
      CURLcode res;

      curl_global_init(CURL_GLOBAL_DEFAULT);
      curl = curl_easy_init();

      if(curl) {
          const char *url = "https://aireiter.com/api/openapi/submit";
          const char *payload = "{\"model\":\"happyhorse_1_0\",\"params\":{\"type\":\"text_to_video\",\"prompt\":\"A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight\",\"resolution\":\"720p\",\"aspect_ratio\":\"16:9\",\"video_length\":5,\"seed\":0},\"out_task_id\":\"happyhorse_1_0_t2v_123456\"}";

          struct curl_slist *headers = NULL;
          headers = curl_slist_append(headers, "Authorization: Bearer <token>");
          headers = curl_slist_append(headers, "Content-Type: application/json");

          curl_easy_setopt(curl, CURLOPT_URL, url);
          curl_easy_setopt(curl, CURLOPT_POSTFIELDS, payload);
          curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

          res = curl_easy_perform(curl);

          if(res != CURLE_OK) {
              fprintf(stderr, "curl_easy_perform() failed: %s\n",
                      curl_easy_strerror(res));
          }

          curl_slist_free_all(headers);
          curl_easy_cleanup(curl);
      }

      curl_global_cleanup();
      return 0;
  }
  ```

  ```objectivec Objective-C theme={null}
  #import <Foundation/Foundation.h>

  int main(int argc, const char * argv[]) {
      @autoreleasepool {
          NSURL *url = [NSURL URLWithString:@"https://aireiter.com/api/openapi/submit"];

          NSDictionary *payload = @{
              @"model": @"happyhorse_1_0",
              @"params": @{
                  @"type": @"text_to_video",
                  @"prompt": @"A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
                  @"resolution": @"720p",
                  @"aspect_ratio": @"16:9",
                  @"video_length": @5,
                  @"seed": @0
              },
              @"out_task_id": @"happyhorse_1_0_t2v_123456"
          };

          NSError *error;
          NSData *jsonData = [NSJSONSerialization dataWithJSONObject:payload
                                                            options:0
                                                              error:&error];

          NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
          [request setHTTPMethod:@"POST"];
          [request setValue:@"Bearer <token>" forHTTPHeaderField:@"Authorization"];
          [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
          [request setHTTPBody:jsonData];

          NSURLSessionDataTask *task = [[NSURLSession sharedSession]
              dataTaskWithRequest:request
              completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
                  if (error) {
                      NSLog(@"Error: %@", error);
                      return;
                  }
                  NSString *result = [[NSString alloc] initWithData:data
                                                          encoding:NSUTF8StringEncoding];
                  NSLog(@"%@", result);
              }];

          [task resume];
          [[NSRunLoop mainRunLoop] run];
      }
      return 0;
  }
  ```

  ```ocaml OCaml theme={null}
  (* Requires cohttp and yojson libraries *)
  open Lwt
  open Cohttp
  open Cohttp_lwt_unix

  let url = "https://aireiter.com/api/openapi/submit"

  let payload = {|{
    "model": "happyhorse_1_0",
    "params": {
      "type": "text_to_video",
      "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
      "resolution": "720p",
      "aspect_ratio": "16:9",
      "video_length": 5,
      "seed": 0
    },
    "out_task_id": "happyhorse_1_0_t2v_123456"
  }|}

  let () =
    let headers = Header.init ()
      |> fun h -> Header.add h "Authorization" "Bearer <token>"
      |> fun h -> Header.add h "Content-Type" "application/json"
    in
    let body = Cohttp_lwt.Body.of_string payload in

    let response = Client.post ~headers ~body (Uri.of_string url) >>= fun (resp, body) ->
      body |> Cohttp_lwt.Body.to_string >|= fun body_str ->
      print_endline body_str
    in
    Lwt_main.run response
  ```

  ```dart Dart theme={null}
  import 'dart:convert';
  import 'package:http/http.dart' as http;

  void main() async {
    final url = Uri.parse('https://aireiter.com/api/openapi/submit');

    final payload = {
          "model": "happyhorse_1_0",
          "params": {
              "type": "text_to_video",
              "prompt": "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
              "resolution": "720p",
              "aspect_ratio": "16:9",
              "video_length": 5,
              "seed": 0
          },
          "out_task_id": "happyhorse_1_0_t2v_123456"
      };

    final response = await http.post(
      url,
      headers: {
        'Authorization': 'Bearer <token>',
        'Content-Type': 'application/json'
      },
      body: jsonEncode(payload),
    );

    print(response.body);
  }
  ```

  ```r R theme={null}
  library(httr)
  library(jsonlite)

  url <- "https://aireiter.com/api/openapi/submit"

  payload <- list(
    model = "happyhorse_1_0",
    params = list(
      type = "text_to_video",
      prompt = "A red paper airplane slowly flies past a bright white photo studio, fixed camera, soft daylight",
      resolution = "720p",
      aspect_ratio = "16:9",
      video_length = 5,
      seed = 0
    ),
    out_task_id = "happyhorse_1_0_t2v_123456"
  )

  response <- POST(
    url,
    add_headers(
      Authorization = "Bearer <token>",
      `Content-Type` = "application/json"
    ),
    body = toJSON(payload, auto_unbox = TRUE),
    encode = "raw"
  )

  cat(content(response, "text"))
  ```
</RequestExample>

<ResponseExample>
  ```json 200 theme={null}
  {
    "statusCode": 200,
    "message": "",
    "data": {
        "out_task_id": "happyhorse_1_0_t2v_123456",
        "status": "pending",
        "estimated_credits": 100,
        "created_at": "2025-12-22T06:03:28.242Z"
    }
  }
  ```

  ```json 400 theme={null}
    {
        "statusCode": 400,
        "message": "Invalid request parameters",
        "ok": false
    }
  ```

  ```json 401 theme={null}
  {
    "error": {
      "code": 401,
      "message": "Authentication failed, please check your API key"
    }
  }
  ```

  ```json 433 theme={null}
    {
      "error": {
        "code": 433,
        "message": "Insufficient account balance, please top up and try again"
      }
    }
  ```

  ```json 500 theme={null}
  {
    "error": {
      "code": 500,
      "message": "Internal server error, please try again later"
    }
  }
  ```
</ResponseExample>

## Workflow Parameter Comparison

| `type` | Required Assets | Duration and Aspect Ratio |
| - | - | - |
| `text_to_video` | `prompt` | `video_length` 3-15 seconds, optional `aspect_ratio` |
| `image_to_video` | `image_url` | `video_length` 3-15 seconds, aspect ratio follows the image |
| `reference_to_video` | `prompt`, `image_url` | `video_length` 3-15 seconds, optional `aspect_ratio` |
| `video_edit` | `prompt`, `video_url` | Duration and aspect ratio follow the source video, output up to 15 seconds |


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