Flux Image Generation API
Flux is an industry-leading image generation model. Through LaoZhang API’s OpenAI-compatible interface, you can easily call Flux Kontext Pro and Max models to generate high-quality images. We offer better pricing than official rates, combined with exchange rate advantages and recharge bonuses to save you more costs.🎯 High-Quality Generation
Flux models are renowned for exceptional image quality and detail, supporting flexible aspect ratios from 3:7 to 7:3.
Flux models are renowned for exceptional image quality and detail, supporting flexible aspect ratios from 3:7 to 7:3.
🌟 Core Features
- 📐 Flexible Ratios: Supports continuous aspect ratio range from 3:7 to 7:3
- 🎨 High-Quality Output: 1 megapixel images with rich details and artistic expression
- 💰 Price Advantage: Better rates than official pricing, cost savings
- 🔧 OpenAI Compatible: Uses standard Images API format, easy integration
- ⏱️ URL Validity: Generated result URLs valid for 10 minutes, download promptly
- 🔄 Reproducibility: Supports seed parameter for consistent results
📋 Model Comparison
Model | Model ID | LaoZhang API Price | Official Price | Savings | Features |
---|---|---|---|---|---|
Flux Kontext Pro | flux-kontext-pro | $0.035/image | $0.040/image | 12.5% | Cost-effective, suitable for batch use |
Flux Kontext Max | flux-kontext-max | $0.07/image | $0.08/image | 12.5% | Highest quality, professional use |
💡 Price Advantage: Call Flux models through LaoZhang API platform, combined with exchange rate advantage (1:7) and recharge bonus policy (top up $100, get +10% bonus), save over 25% compared to official pricing!
📐 Supported Aspect Ratios
Flux models support continuous aspect ratio range from 3:7 to 7:3, maintaining approximately 1 megapixel total. Here are some common ratio examples:Ratio | Type | Approximate Size | Use Case |
---|---|---|---|
1:1 | Square | 1024×1024 | General use, social media avatars |
2:3 | Vertical | ~832×1248 | Phone wallpapers, portrait photos |
3:2 | Horizontal | ~1248×832 | Desktop wallpapers, landscape photos |
4:3 | Standard Horizontal | ~1182×886 | Traditional displays, presentations |
16:9 | Widescreen | ~1408×792 | Modern displays, video thumbnails |
9:16 | Vertical Screen | ~792×1408 | Mobile videos, vertical posters |
21:9 | Ultra-wide | ~1680×720 | Movie posters, ultra-wide displays |
3:7 | Narrowest Vertical | ~662×1544 | Bookmarks, vertical long images |
7:3 | Widest Horizontal | ~1544×662 | Website banners, panoramic images |
📏 Custom Ratios: Besides the examples above, you can use any ratio within the 3:7 to 7:3 range, such as
5:4
, 4:5
, 16:10
, etc. The system automatically adjusts size to maintain approximately 1 megapixel total area.🚀 Quick Start
Basic Example
📝 Parameter Details
Parameters Passed via extra_body
Parameter | Type | Range/Options | Description | Default |
---|---|---|---|---|
aspect_ratio | string | 3:7 to 7:3 | Output image aspect ratio | ”1:1” |
seed | integer | Any integer | Random seed for reproducibility | Random |
safety_tolerance | integer | 0-6 | Content safety control, 0=strictest, 6=most lenient | 2 |
output_format | string | ”jpeg”, “png” | Output image format | ”jpeg” |
prompt_upsampling | boolean | true/false | Auto-enhance prompt | false |
💡 Prompt Enhancement: Enabling
prompt_upsampling
allows AI to automatically optimize and expand your prompt, but may change original intent. Recommended to test first.💡 Best Practices
1. URL Management and Download Strategy
Since Flux generated image URLs are only valid for 10 minutes, proper download strategy is crucial:2. Model Selection Guide
Flux Kontext Pro:- ✅ Daily design needs
- ✅ Batch content generation
- ✅ Cost-sensitive projects
- ✅ Rapid prototyping
- ✅ Professional design works
- ✅ Commercial use images
- ✅ High-quality requirements
- ✅ Print output needs
3. Prompt Optimization
Based on official documentation recommendations, detailed and descriptive prompts yield better results:⚠️ Important Notes
-
URL Validity:
- Generated image URLs are only valid for 10 minutes
- Must download before expiration
- Recommended to download immediately after generation
-
Parameter Passing:
- All Flux-specific parameters must be passed via
extra_body
- Cannot use Flux proprietary parameters directly in top-level parameters
- All Flux-specific parameters must be passed via
-
Aspect Ratio Range:
- Supports continuous range from 3:7 to 7:3
- Not limited to fixed ratios, can use any ratio within range
- System auto-adjusts size to maintain ~1 megapixel
-
Content Safety:
safety_tolerance
parameter controls moderation strictness (0-6)- 0 = strictest, 6 = most lenient
- Default value 2 suitable for most scenarios
-
Output Format:
- Default JPEG format, smaller files
- PNG format higher quality but larger files
- Choose appropriate format based on use case
-
Prompt Processing:
prompt_upsampling
auto-optimizes prompts- May change original intent, recommended to test first
- Significant effect on simple prompts
🔍 FAQ
Q: Why do image URLs expire?
A: This is Flux official’s security design. All generated image URLs automatically expire after 10 minutes. Please download and save promptly.Q: How is Flux different from other models?
A: Flux models focus on high-quality image generation, supporting flexible aspect ratios (3:7 to 7:3), particularly suitable for professional designs requiring specific dimensions.Q: How to choose between Pro and Max versions?
A:- Pro: Cost-effective, $0.035/image, suitable for daily use and batch generation
- Max: Highest quality, $0.07/image, suitable for commercial works and professional needs
Q: Can I use any aspect ratio?
A: You can use any ratio within the 3:7 to 7:3 range, such as5:4
, 16:10
, 21:9
, etc. The system auto-adjusts to maintain ~1 megapixel.
Q: How to set safety_tolerance?
A:- 0-1: Corporate/commercial environment, strictest
- 2-3: General creation, balanced mode (recommended)
- 4-6: Artistic creation, more lenient
Q: What does prompt_upsampling do?
A: When enabled, AI automatically expands and optimizes your prompt, especially suitable for brief prompts. But may change original meaning, recommended to test first.Q: How to ensure reproducible results?
A: Use the sameseed
value and identical other parameters to generate consistent results. This is helpful for iterative design.
Q: How to avoid URL expiration in batch generation?
A:- Download immediately after generation
- Use concurrency control to avoid excessive processing time
- Consider using async processing for efficiency
🎯 Multi-Image Processing Solution
Flux API natively only supports single image input, but through our batch processing scripts, you can achieve dual-image composition processing.Use Cases
- Pattern Transfer: Transfer design patterns onto clothing models
- Style Fusion: Combine characteristic elements from two images
- Comparison Display: Show original and target effect simultaneously
Technical Approach
Image Merging Strategy
Image Merging Strategy
- Auto Download: Fetch two input images from URLs
- Smart Merge: Use Python PIL to stitch images side by side
- API Call: Use merged image as single input
- Result Processing: AI performs intelligent processing based on merged image
Batch Processing Capability
Batch Processing Capability
- Supports automated processing of multiple image pairs
- Unified prompt control for processing effects
- Automatic result download and file management
- Complete error handling and logging
Quick Start
Dependency Requirements: Script requires
jq
, Python3 + PIL
, and optionally ImageMagick
. See script help for detailed installation instructions.🔗 Related Resources
- Complete Example Code
- Multi-Image Processing Script
- Flux Image Edit API - Edit existing images
- Pricing Calculator - Real-time price query
- Online Demo - Test Flux effects
🎨 Pro Tip: Combining different aspect ratios and model versions can meet various needs from social media to professional design!