Sora 2 API Official Relay vs Official Reverse Full Comparison: Character Reference Feature Differences and Selection Guide for 5 Scenarios

Sora 2's character reference feature has been a huge focus for developers. In this post, we'll compare the Official Forwarding API and the Reverse Engineered API, looking at character referencing, @CharacterID support, and costs to help you decide which path to take.

The Bottom Line: By the end of this article, you'll know exactly which Sora 2 API fits your needs—whether you're prioritizing character consistency, saving on costs, or looking for full feature access.

Sora 2 Character Reference Background

In the world of AI video generation, character consistency is one of the biggest hurdles for creators. Sora 2’s Character feature lets you:

Official Positioning of Sora 2 Character Features

According to OpenAI's official docs, the Character Cameo feature first launched on the Sora Web platform (sora.chatgpt.com), allowing users to upload videos and create reusable characters. While this works seamlessly on the app and web interfaces, support at the API level is a different story.

Official Docs: help.openai.com/en/articles/12435986-generating-content-with-characters

Sora 2 Official Forward vs. Official Reverse: Core Differences

Understanding the difference between "Official Forward" and "Official Reverse" is the first step in choosing the right solution for your project.

What is the Official Forward API?

Official Forwarding refers to the method of calling through the official OpenAI API endpoints (platform.openai.com):

• Authenticated via official OpenAI API Keys.
• Routes through official OpenAI servers.
• Billed by the second ($0.10 – $0.50/sec).
• Governed by official content moderation policies.

What is the Official Reverse API?

Official Reverse refers to APIs encapsulated by reverse-engineering the Sora iOS App or Web endpoints:

• Based on reverse-engineered App interfaces.
• Supports the native Character referencing feature.
• Billed per request (approx. $0.12/video).
• Functionality is much closer to the consumer-facing app experience.

Core Functionality Comparison Table

Why doesn't Official Forward support @CharacterID?

Based on discussions in the OpenAI developer community, the current design focus for the official API is:

1. Standardized Interface Priority: Providing three standard input modes: text-to-video, image-to-video, and video-to-video.
2. Safety Compliance: Strict face detection often blocks reference_image inputs containing real human faces.
3. Character Roadmap: OpenAI has indicated that character reference features will be gradually opened to the API.

Community Discussion: community.openai.com/t/how-to-use-characters-funcion-by-api/1368202

Sora 2 API Character Reference Technical Implementation

Understanding the underlying implementation helps you make a smarter choice for your workflow.

Alternatives for the Official Forward API

Since Official Forwarding doesn't support @CharacterID yet, developers need to use the reference_video parameter as a workaround:

import openai

client = openai.OpenAI(
    api_key="YOUR_API_KEY",
    base_url="https://api.apiyi.com/v1"  # Using APIYI unified interface
)

# Official Forward Solution: Use reference_video for consistency
response = client.video.generate(
    model="sora-2",
    prompt="A girl drinking coffee in a cafe",
    reference_video="https://example.com/character_source.mp4",
    influence_strength=0.8  # 0-1, higher means better character consistency
)

Limitations of the Official Forward approach:

• High influence_strength can restrict the creative freedom of the scene.
• You can't precisely control which character traits are preserved.
• Real human face images might be blocked by content moderation.

Character Referencing in the Official Reverse API

The Official Reverse API provides two ways to create characters:

Method 1: Extract Character from a Video URL

import requests

# Use APIYI Official Reverse endpoint
base_url = "https://api.apiyi.com/v1"

# Step 1: Create the character
create_response = requests.post(
    f"{base_url}/sora/characters",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "video_url": "https://example.com/source_video.mp4",
        "name": "coffee_girl",
        "description": "Girl wearing a white dress"
    }
)
character_id = create_response.json()["character_id"]
# Returns: char_abc123xyz

# Step 2: Generate video using @CharacterID
generate_response = requests.post(
    f"{base_url}/sora/generate",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "prompt": f"@{character_id} walking on the beach at sunset",
        "duration": 10
    }
)

Method 2: Extract Character from a Previously Generated Video

# If you already have a task ID from a Sora generation
extract_response = requests.post(
    f"{base_url}/sora/characters/extract",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "task_id": "task_xyz789",  # ID of a previous generation task
        "name": "beach_girl"
    }
)

import requests
import time

class SoraCharacterManager:
    """Sora Character Manager - Supports Official Reverse API"""

    def __init__(self, api_key: str):
        self.api_key = api_key
        self.base_url = "https://api.apiyi.com/v1"  # APIYI unified interface
        self.headers = {"Authorization": f"Bearer {api_key}"}

    def create_character(self, video_url: str, name: str, description: str = "") -> str:
        """Create a character from a video"""
        response = requests.post(
            f"{self.base_url}/sora/characters",
            headers=self.headers,
            json={
                "video_url": video_url,
                "name": name,
                "description": description
            }
        )
        response.raise_for_status()
        return response.json()["character_id"]

    def list_characters(self) -> list:
        """List all characters"""
        response = requests.get(
            f"{self.base_url}/sora/characters",
            headers=self.headers
        )
        response.raise_for_status()
        return response.json()["characters"]

    def generate_with_character(self, character_id: str, prompt: str, duration: int = 5) -> dict:
        """Generate video using a character ID"""
        full_prompt = f"@{character_id} {prompt}"
        response = requests.post(
            f"{self.base_url}/sora/generate",
            headers=self.headers,
            json={
                "prompt": full_prompt,
                "duration": duration
            }
        )
        response.raise_for_status()
        return response.json()

    def wait_for_video(self, task_id: str, timeout: int = 300) -> str:
        """Wait for video generation to complete"""
        start_time = time.time()
        while time.time() - start_time < timeout:
            response = requests.get(
                f"{self.base_url}/sora/tasks/{task_id}",
                headers=self.headers
            )
            result = response.json()
            if result["status"] == "completed":
                return result["video_url"]
            elif result["status"] == "failed":
                raise Exception(f"Generation failed: {result.get('error')}")
            time.sleep(5)
        raise TimeoutError("Video generation timed out")

# Usage Example
manager = SoraCharacterManager("YOUR_API_KEY")

# Create a character
char_id = manager.create_character(
    video_url="https://example.com/my_character.mp4",
    name="product_mascot",
    description="Company mascot image"
)

# Generate a series of videos
scenes = [
    "working in the office",
    "giving a speech in a meeting room",
    "drinking coffee in the lounge"
]

for scene in scenes:
    task = manager.generate_with_character(char_id, scene, duration=5)
    video_url = manager.wait_for_video(task["task_id"])
    print(f"Scene '{scene}' completed: {video_url}")

🎯 Pro Tip: For real-world development, we recommend getting access to both Official Forward and Official Reverse interfaces through the APIYI (apiyi.com) platform. This lets you switch flexibly based on your project's specific needs.

Recommended Scenarios for Sora 2 Character Reference

Now that we've cleared up the technical differences, let's look at some specific scenarios to help you decide which path to take.

Scenario 1: When to Choose the Official Forwarded API

Typical User Profile:

• AI application teams at listed companies
• Projects requiring formal invoices and contracts
• Scenarios where service stability is the top priority

Scenario 2: When to Choose the Official Reverse API

Typical User Profile:

• Short video creators
• Indie game developers
• Virtual YouTuber (VTuber) operations teams
• AI video application startups

Scenario 3: Using Both APIs Simultaneously

For complex projects, a hybrid approach using both APIs might be your best bet:

class HybridSoraClient:
    """Hybrid Sora Client - Intelligently chooses between Official Forwarded/Reverse"""

    def __init__(self, api_key: str):
        self.base_url = "https://api.apiyi.com/v1"
        self.api_key = api_key

    def generate(self, prompt: str, use_character: bool = False,
                 character_id: str = None, priority: str = "cost"):
        """
        Intelligently route generation requests

        Args:
            prompt: Video description
            use_character: Whether to use a character
            character_id: Character ID
            priority: Priority - "cost" (prefer lower price) / "stability" (prefer uptime)
        """
        # Decision logic
        if use_character and character_id:
            # Character features require the Official Reverse API
            return self._generate_reverse(prompt, character_id)
        elif priority == "stability":
            # Stability priority, use Official Forwarded API
            return self._generate_official(prompt)
        else:
            # Cost priority, use Official Reverse API
            return self._generate_reverse(prompt)

    def _generate_official(self, prompt: str):
        """Use Official Forwarded API"""
        # Official Forwarded implementation...
        pass

    def _generate_reverse(self, prompt: str, character_id: str = None):
        """Use Official Reverse API"""
        # Official Reverse implementation...
        pass

Sora 2 API Pricing Breakdown

Cost is always a major factor when choosing an API solution.

Detailed Price Comparison

Monthly Cost Estimation

Let's say a video creation team needs to generate 500 ten-second videos per month:

💰 Cost Optimization: For budget-conscious projects, the Official Reverse interface provided by APIYI (apiyi.com) can save you over 80%. This advantage is even more pronounced for series content creation that requires character consistency.

Sora 2 Character Consistency: A Hands-on Comparison

We've conducted a hands-on comparison of character consistency between these two solutions.

Test Methodology

Test Results

Key Findings

1. Limitations of Official API reference_video:

   • Setting influence_strength too high can restrict creative expression.
   • Setting it too low causes character consistency to drop.
   • The "sweet spot" varies significantly depending on the character and scene.

2. Advantages of Reverse API @CharacterID:

   • Character traits are persistently stored within the system.
   • Automatic matching when called, no need for parameter fine-tuning.
   • Supports multiple characters appearing in the same shot.

FAQ

Summary

Sora 2 Official and Official Reverse APIs each have their own positioning and strengths:

💡 Choice Advice: Which API you choose mainly depends on whether you need character consistency features. If you're looking to create character-based video series, the @CharacterID feature in the Official Reverse API is pretty much a must-have. However, if you value stability and official support more, the Official API is the safer bet. We recommend using the APIYI (apiyi.com) platform to access both APIs simultaneously. This lets you switch flexibly based on your project's needs—enjoying the character features and cost benefits of the Reverse API while relying on the Official API for service stability when it matters most.

References

1. OpenAI Sora Character Features Documentation: Official guide on creating and using characters

   • Link: help.openai.com/en/articles/12435986-generating-content-with-characters

2. OpenAI Developer Community Discussion: Support status for API character features

   • Link: community.openai.com/t/how-to-use-characters-funcion-by-api/1368202

3. Sora 2 Official Launch Page: Product overview and feature updates

   • Link: openai.com/index/sora-2/

4. OpenAI API Documentation – Sora 2: Official API endpoint specifications

   • Link: platform.openai.com/docs/models/sora-2

This article was originally created by the APIYI Team. For technical discussions, please visit apiyi.com