API Reference

Basic Information

Endpoint: https://api.laozhang.ai/v1/chat/completionsWith Watermark Endpoint: https://api.laozhang.ai/v1/chat/completions?watermark=trueMethod: POSTAuthentication: Bearer Token (API Key)Content Type: application/json

10/18 New Feature: Watermark OptionBy default, generated videos have no watermark. To generate videos with Sora native watermark, add the parameter ?watermark=true to the URL.

Authentication

Include your API key in the request header:

Authorization: Bearer YOUR_API_KEY

Request Format

Basic Structure

{
  "model": "sora_video2",
  "messages": [
    {
      "role": "user",
      "content": [...]
    }
  ],
  "stream": false
}

Request Parameters

Parameter	Type	Required	Description
`model`	string	✓	Model name, see Supported Models
`messages`	array	✓	Message array
`stream`	boolean	✗	Whether to enable streaming output, default `false`

Messages Array

Each message object contains:

Field	Type	Required	Description
`role`	string	✓	Fixed as `"user"`
`content`	array	✓	Content array, containing text or images

Content Array

Supports two types of content:

Text Content

{
  "type": "text",
  "text": "Video description text"
}

Field	Type	Required	Description
`type`	string	✓	Fixed as `"text"`
`text`	string	✓	Video generation prompt

Image Content (Optional)

{
  "type": "image_url",
  "image_url": {
    "url": "https://example.com/image.png"
  }
}

Field	Type	Required	Description
`type`	string	✓	Fixed as `"image_url"`
`image_url.url`	string	✓	Image URL or Base64

Image Restrictions

Maximum 1 image
Supports URL or Base64 format
Recommended resolution not exceeding 2048×2048
Real person photos not supported

Supported Models

Model Name	Resolution	Duration	Price
`sora_video2`	704×1280 (Portrait)	10s	$0.15
`sora_video2-landscape`	1280×704 (Landscape)	10s	$0.15

Due to official OpenAI computing power limitations, -hd and -15s versions are temporarily unavailable.

Response Format

Non-streaming Response

{
  "id": "foaicmpl-xxx",
  "object": "chat.completion",
  "created": 1759759480,
  "model": "sora_video2",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "```json\n{\n    \"prompt\": \"...\",\n    \"mode\": \"Portrait Mode\"\n}\n```\n\n> ✅ Video generated successfully, [click here](https://sora.gptkey.asia/assets/sora/xxx.mp4) to view video~~~\n\n"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 17,
    "completion_tokens": 244,
    "total_tokens": 261
  }
}

Response Field Description

Field	Type	Description
`id`	string	Request unique identifier
`object`	string	Object type
`created`	integer	Creation timestamp
`model`	string	Model used
`choices[].message.content`	string	Content containing video link
`choices[].finish_reason`	string	Completion reason, `"stop"` indicates success
`usage`	object	Token usage statistics

Streaming Response (SSE)

When "stream": true is enabled, returns Server-Sent Events format:

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{"role":"assistant"},"finish_reason":null}]}

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{"content":"```json\n{\n    \"prompt\": \"...\"\n}\n```\n\n"},"finish_reason":null}]}

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{"content":"> ⌛️ Task is in queue, please wait patiently...\n\n"},"finish_reason":null}]}

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{"content":"> 🏃 Progress: 36.0%\n\n"},"finish_reason":null}]}

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{"content":"> ✅ Video generated successfully, [click here](https://sora.gptkey.asia/assets/sora/xxx.mp4) to view video~~~\n\n"},"finish_reason":null}]}

data: {"id":"foaicmpl-xxx","object":"chat.completion.chunk","created":1759759480,"model":"sora_video2","choices":[{"index":0,"delta":{},"finish_reason":"stop"}],"usage":{"prompt_tokens":17,"completion_tokens":244,"total_tokens":261}}

data: [DONE]

Streaming Response Fields

Field	Type	Description
`choices[].delta.role`	string	Role, only included in first message
`choices[].delta.content`	string	Incremental content (progress or video link)
`choices[].finish_reason`	string	When `"stop"`, indicates completion
`usage`	object	Last message contains usage statistics

Complete Examples

Text-to-Video

curl -X POST "https://api.laozhang.ai/v1/chat/completions" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora_video2",
    "messages": [
      {
        "role": "user",
        "content": [
          {
            "type": "text",
            "text": "A cute cat playing with a ball in a sunny garden"
          }
        ]
      }
    ]
  }'

Image-to-Video (URL)

curl -X POST "https://api.laozhang.ai/v1/chat/completions" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora_video2",
    "messages": [
      {
        "role": "user",
        "content": [
          {
            "type": "text",
            "text": "Generate video: Make this figurine jump out from the desk and become a living person~"
          },
          {
            "type": "image_url",
            "image_url": {
              "url": "https://filesystem.site/cdn/download/20250407/OhFd8JofOAJCsNOCsM1Y794qnkNO3L.png"
            }
          }
        ]
      }
    ]
  }'

Image-to-Video (Base64)

import openai
import base64

client = openai.OpenAI(
    api_key="YOUR_API_KEY",
    base_url="https://api.laozhang.ai/v1"
)

# Read local image
def encode_image(image_path):
    with open(image_path, "rb") as image_file:
        return base64.b64encode(image_file.read()).decode('utf-8')

base64_image = encode_image("/path/to/image.png")

response = client.chat.completions.create(
    model="sora_video2",
    messages=[
        {
            "role": "user",
            "content": [
                {
                    "type": "text",
                    "text": "Make this scene come alive"
                },
                {
                    "type": "image_url",
                    "image_url": {
                        "url": f"data:image/png;base64,{base64_image}"
                    }
                }
            ]
        }
    ]
)

print(response.choices[0].message.content)

Streaming Output

import openai

client = openai.OpenAI(
    api_key="YOUR_API_KEY",
    base_url="https://api.laozhang.ai/v1"
)

stream = client.chat.completions.create(
    model="sora_video2",
    messages=[
        {
            "role": "user",
            "content": [
                {
                    "type": "text",
                    "text": "A cute cat playing with a ball in a sunny garden"
                }
            ]
        }
    ],
    stream=True
)

for chunk in stream:
    if chunk.choices[0].delta.content:
        print(chunk.choices[0].delta.content, end='', flush=True)

Error Codes

HTTP Status Code	Error Type	Description
400	Bad Request	Invalid request parameters
401	Unauthorized	Invalid or missing API Key
402	Payment Required	Insufficient balance
429	Too Many Requests	Too many requests
500	Internal Server Error	Internal server error
503	Service Unavailable	Service temporarily unavailable

Error Response Format

{
  "error": {
    "message": "Error description",
    "type": "invalid_request_error",
    "code": "invalid_api_key"
  }
}

Rate Limits

Currently no strict rate limits, but recommended:

Control concurrency when batch generating (recommended 2-3)
Avoid large number of requests in short time
Set reasonable retry intervals

Best Practices

Timeout Settings

Video generation takes 2-4 minutes, recommend setting timeout to 5-10 minutes.

import httpx
import openai

client = openai.OpenAI(
    api_key="YOUR_API_KEY",
    base_url="https://api.laozhang.ai/v1",
    http_client=httpx.Client(timeout=300.0)  # 5 minutes
)

Error Handling

Add retry logic to handle temporary errors:

import time

max_retries = 3
for i in range(max_retries):
    try:
        response = client.chat.completions.create(...)
        break
    except Exception as e:
        if i < max_retries - 1:
            print(f"Error, retrying in 30 seconds...")
            time.sleep(30)
        else:
            raise

Video Download

Download immediately after generation (valid for 1 day):

import requests
import re

# Extract link
video_url = re.search(r'https://[^\s\)]+\.mp4', content).group(0)

# Download
response = requests.get(video_url, stream=True)
with open('video.mp4', 'wb') as f:
    for chunk in response.iter_content(chunk_size=8192):
        f.write(chunk)

Streaming Output Monitoring

Use streaming output to view progress in real-time:

stream = client.chat.completions.create(
    model="sora_video2",
    messages=[...],
    stream=True
)

for chunk in stream:
    if chunk.choices[0].delta.content:
        content = chunk.choices[0].delta.content
        print(content, end='', flush=True)

SDK Support

Official SDK

Python: openai >= 1.0.0
Node.js: openai >= 4.0.0

Third-party SDK

Any SDK compatible with OpenAI API format can be used, just modify base_url.

Technical Specifications

Specification	Value
Video Encoding	H.264
Audio Encoding	AAC
Frame Rate	24 fps
Format	MP4
Watermark	None
Audio	Supported
Max File Size	~50MB (depends on duration and quality)

Next Steps

Quick Start

View quick start guide

Usage Examples

View more code examples

Model Pricing

Learn about model comparison and pricing

FAQ

View frequently asked questions

Getting Started

Core API

Video Generation APIs

Image Generation APIs

AI Understanding

Basic Information

Authentication

Request Format

Basic Structure

Request Parameters

Messages Array

Content Array

Text Content

Image Content (Optional)

Supported Models

Response Format

Non-streaming Response

Response Field Description

Streaming Response (SSE)

Streaming Response Fields

Complete Examples

Text-to-Video

Image-to-Video (URL)

Image-to-Video (Base64)

Streaming Output

Error Codes

Error Response Format

Rate Limits

Best Practices

SDK Support

Official SDK

Third-party SDK

Technical Specifications

Next Steps

Quick Start

Usage Examples

Model Pricing

FAQ

Getting Started

Core API

Video Generation APIs

Image Generation APIs

AI Understanding

​Basic Information

​Authentication

​Request Format

​Basic Structure

​Request Parameters

​Messages Array

​Content Array

​Text Content

​Image Content (Optional)

​Supported Models

​Response Format

​Non-streaming Response

​Response Field Description

​Streaming Response (SSE)

​Streaming Response Fields

​Complete Examples

​Text-to-Video

​Image-to-Video (URL)

​Image-to-Video (Base64)

​Streaming Output

​Error Codes

​Error Response Format

​Rate Limits

​Best Practices

​SDK Support

​Official SDK

​Third-party SDK

​Technical Specifications

​Next Steps

Quick Start

Usage Examples

Model Pricing

FAQ

Basic Information

Authentication

Request Format

Basic Structure

Request Parameters

Messages Array

Content Array

Text Content

Image Content (Optional)

Supported Models

Response Format

Non-streaming Response

Response Field Description

Streaming Response (SSE)

Streaming Response Fields

Complete Examples

Text-to-Video

Image-to-Video (URL)

Image-to-Video (Base64)

Streaming Output

Error Codes

Error Response Format

Rate Limits

Best Practices

SDK Support

Official SDK

Third-party SDK

Technical Specifications

Next Steps