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Prerequisites

1 Get API Key Log in to laozhang.ai console to obtain your API key 2 Configure Billing Mode Edit token settings and choose one of the following billing modes (same price for both):
  • Volume Priority (Recommended): Uses balance billing first, automatically switches when balance is insufficient. Suitable for most users
  • Pay-per-call: Direct deduction for each call. Suitable for strict budget control scenarios
Both modes have exactly the same price, Veo-3.1 series 0.15−0.15-0.25/call, only the billing method differs. Token Settings If billing mode is not configured, API calls will fail. You must complete this configuration first!

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Introduction

Veo-3.1 is Google’s latest generation video generation model series, supporting high-quality video content generation through text descriptions or image inputs. The entire series is fully compatible with OpenAI Chat Completions API format, making it easy for developers to integrate quickly.

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Core Features

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Text-to-Video

Generate videos from pure text descriptions, supporting complex scenes and action descriptions

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Image-to-Video

Generate transition videos or animation effects based on 1-2 reference images

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OpenAI Compatible

Uses standard Chat Completions API format, no need to learn new interfaces

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Streaming Response

Supports streaming returns for real-time generation progress and results

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Model Series

Veo-3.1 provides multiple model variants to meet different scenario requirements:

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Standard Models

veo-3.1 - Standard Price: $0.25 / requestFeatures:
  • Excellent overall performance
  • Suitable for most scenarios
  • Stable generation quality
Use Cases: General video generation, content creation veo-3.1-fast - Fast Price: $0.15 / requestFeatures:
  • Faster generation speed
  • High cost-effectiveness
  • Suitable for rapid iteration
Use Cases: Batch generation, quick testing

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Image-to-Video Models (Support Image Input)

veo-3.1-fl - Image-to-Video Standard Price: $0.25 / requestFeatures:
  • Supports 1-2 image inputs
  • Can generate image transition animations
  • Bring static images to life
Use Cases: Image animation, image transition videos veo-3.1-fast-fl - Image-to-Video Fast Price: $0.15 / requestFeatures:
  • Fast image-to-video generation
  • Supports image input
  • High cost-effectiveness
Use Cases: Batch image animation production

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Landscape Models

veo-3.1-landscape - Landscape Standard Price: $0.25 / requestFeatures:
  • Optimized for landscape scenarios
  • 16:9 or wider aspect ratio
  • Suitable for professional production
Use Cases: Film production, commercial videos veo-3.1-landscape-fast - Landscape Fast Price: $0.15 / requestFeatures:
  • Fast landscape video generation
  • Maintains picture quality
  • Efficient batch processing
Use Cases: Batch landscape content production veo-3.1-landscape-fl - Landscape Image-to-Video Price: $0.25 / requestFeatures:
  • Landscape + image input support
  • Professional-grade output
  • Excellent detail preservation
Use Cases: Landscape image animation, professional landscape production veo-3.1-landscape-fast-fl - Landscape Image-to-Video Fast Price: $0.15 / requestFeatures:
  • Fast + image input + landscape
  • Triple feature combination
  • Extremely high cost-effectiveness
Use Cases: Large-scale landscape image animation production

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Price Comparison

Model NamePriceSpeedAspect RatioImage SupportRecommended Use
veo-3.1$0.25StandardGeneral❌Text-to-video general scenarios
veo-3.1-fast$0.15FastGeneral❌Text-to-video quick testing
veo-3.1-fl$0.25StandardGeneral✅Image-to-video standard quality
veo-3.1-fast-fl$0.15FastGeneral✅Image-to-video fast processing
veo-3.1-landscape$0.25StandardLandscape❌Landscape text-to-video
veo-3.1-landscape-fast$0.15FastLandscape❌Landscape text-to-video fast
veo-3.1-landscape-fl$0.25StandardLandscape✅Landscape image-to-video
veo-3.1-landscape-fast-fl$0.15FastLandscape✅Landscape image-to-video fast

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Generation Methods

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Text-to-Video

Generate video content through natural language descriptions: 
{
  "messages": [{
    "role": "user",
    "content": [
      {
        "type": "text",
        "text": "Generate a video of two cats and a dog fighting"
      }
    ]
  }],
  "model": "veo-3.1",
  "stream": true,
  "n": 2
}

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Image-to-Video

Generate video content based on reference images: 
{
  "messages": [{
    "role": "user",
    "content": [
      {
        "type": "text",
        "text": "Generate a smooth transition video based on two images"
      },
      {
        "type": "image_url",
        "image_url": {
          "url": "Start frame image URL or base64"
        }
      },
      {
        "type": "image_url",
        "image_url": {
          "url": "End frame image URL or base64 (optional)"
        }
      }
    ]
  }],
  "model": "veo-3.1-fl",
  "stream": true
}

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Core Parameters

model string required Select the Veo-3.1 model variant to use messages array required Message array containing user input, supporting text and image types stream boolean default:“false” Whether to enable streaming response, recommended to set to true for real-time progress n integer default:“1” Number of videos to generate, range 1-4, can generate multiple different results simultaneously

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Billing Information

Important: Veo-3.1 models require pay-per-use tokens, not pay-as-you-go tokens. Please create a “pay-per-use” type token in the Console. Pay-per-request: Each successful API call is charged at the selected model’s unit price, failed requests are not charged

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Billing Rules

  • Single Request: Charged at model price (0.15or0.15 or 0.15or0.25)
  • Multiple Results: Setting n=2 generates 2 videos, charged for 2 requests
  • Failed Retries: Failed generations are not charged, can retry for free
  • Streaming Response: No additional charge

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Technical Advantages

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High-Quality Output

Advanced video generation algorithms ensure smooth and natural footage

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Fast Response

Fast series models can return results in seconds

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Flexible Control

Supports text and image combination input for precise content control

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Standard Interface

Fully compatible with OpenAI API, zero learning curve

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Batch Processing

Supports generating multiple results simultaneously through n parameter

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Real-time Progress

Streaming response provides real-time generation status feedback

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Quick Start

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Quick Start Guide

View complete quick start tutorial with detailed code examples

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Use Cases

  • Content Creation
  • Professional Production
  • Batch Generation
  • Social media short videos
  • Marketing clips
  • Product showcase animations
  • Educational training content
  • Film visual effects preview
  • Ad creative testing
  • Animation prototyping
  • Concept validation videos
  • Automated content production
  • A/B testing materials
  • Multi-version rapid iteration
  • Dataset generation

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Next Steps

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Quick Start

Get started with Veo-3.1 API in 5 minutes

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Code Examples

View complete example code in various languages

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Best Practices

Learn how to write better prompts

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Troubleshooting

Check common issues and errors