uvsn_flutter

UVSN Image Analyzer

A Flutter application that analyzes images to extract mean RGB values, chromaticity coordinates, and EXIF metadata, with support for various image formats including RAW files. Now with optional Python backend for enhanced RAW format support!

🆕 Dual Processing Modes

Flutter Processing: Fast, client-side analysis for standard formats
Python API Processing: Enhanced RAW support with better compression handling
Toggle Between Modes: Switch seamlessly in the app interface

Features

Image Analysis

Mean RGB Extraction: Calculates average red, green, and blue values from images
Chromaticity Analysis: Computes chromaticity coordinates (r, g) and standard deviations
EXIF Data Support: Extracts and displays metadata from images that contain EXIF information
Photographic Calculations: Calculates S_v, A_v, T_v, and B_v values from EXIF data
Multiple Format Support: Handles JPG, PNG, BMP, GIF, WebP, DNG, RAW, CR2, NEF, ARW, RW2 formats
Enhanced RAW Support: Python backend handles DNG compression type 7 and other advanced formats

Image Input

Gallery Selection: Pick images from device gallery
Camera Capture: Take photos directly with the device camera
Bulk Processing: Select and analyze multiple images at once
Native File Picker: Uses platform-specific file pickers for optimal experience

Export Functionality

Individual Export: Export analysis results for single images as JSON
Bulk Export: Export all analyses in a single JSON file
Structured Data: Includes RGB values, EXIF metadata, file information, and analysis timestamps
Cross-Platform: Works on iOS, Android, and Web platforms

User Interface

Modern Material Design: Clean, intuitive interface with Material 3 design
Responsive Layout: Adapts to different screen sizes and orientations
Dark/Light Theme: Automatic theme switching based on system preferences
Real-time Feedback: Loading indicators and progress updates during analysis

Supported Platforms

✅ iOS
✅ Android
✅ Web
✅ macOS
✅ Windows
✅ Linux

Installation

Prerequisites

Flutter SDK (3.8.1 or higher)
Dart SDK
iOS: Xcode (for iOS builds)
Android: Android Studio (for Android builds)

Setup

Clone the repository

git clone <repository-url>
cd uvsn_image_analyzer

Install dependencies
```
flutter pub get
```

Run the app

# For iOS
flutter run -d ios
   
# For Android
flutter run -d android
   
# For Web
flutter run -d chrome

Optional: Python API Setup

For enhanced RAW format support, set up the Python backend:

Install Python dependencies

cd api
python3 -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate
pip install -r requirements.txt

Run the Python API

uvicorn analyze:app --reload --port 3000

Enable in Flutter app
- Look for the cloud icon toggle in the app bar
- Switch it on to use Python API processing

See DEPLOYMENT.md for full deployment instructions.

Usage

Basic Workflow

Launch the app - The main screen shows an empty state with instructions
Add Images - Tap the “Add Images” button to select images from gallery or camera
View Analysis - Each analyzed image displays:
- Image thumbnail
- File information (name, format, size)
- Mean RGB values with color-coded indicators
- EXIF metadata (if available)
Export Results - Use individual export buttons or bulk export from the menu

Export Format

Individual Export

{
  "imagePath": "/path/to/image.jpg",
  "fileName": "image.jpg",
  "meanRed": 128.5,
  "meanGreen": 156.2,
  "meanBlue": 89.7,
  "exifData": {
    "Make": "Canon",
    "Model": "EOS R5",
    "DateTime": "2024:01:15 14:30:25",
    "ExposureTime": "1/125",
    "FNumber": "f/2.8",
    "ISO": "100"
  },
  "analysisDate": "2024-01-15T14:30:25.123Z",
  "fileSize": "2.5 MB",
  "imageFormat": "jpg"
}

Bulk Export

{
  "exportDate": "2024-01-15T14:30:25.123Z",
  "totalImages": 3,
  "analyses": [
    // Array of individual analysis objects
  ]
}

Technical Details

Architecture

Models: Data classes for image analysis results
Services: Business logic for image processing, file handling, and export
Widgets: Reusable UI components
Screens: Main application screens

Key Dependencies

Flutter:

image: Image processing and RGB calculation
exif: EXIF metadata extraction
http: HTTP client for Python API communication

Python API (Optional):

fastapi: Web framework for API endpoints
rawpy: Enhanced RAW format support via libraw
Pillow: Image processing
numpy: Efficient numerical computations
exifread: EXIF metadata extraction
image_picker: Camera and gallery access
file_picker: File selection
path_provider: File system access
permission_handler: Platform permissions
flutter_staggered_grid_view: Responsive grid layout

Performance Optimizations

Pixel Sampling: Analyzes every 10th pixel for faster processing
Async Processing: Non-blocking image analysis
Memory Management: Efficient image loading and disposal
Error Handling: Graceful handling of unsupported formats and corrupted files

Permissions

iOS

Camera access for photo capture
Photo library access for image selection
Photo library write access for exports

Android

Camera permission for photo capture
Storage permission for file access
External storage permission for exports

Troubleshooting

Common Issues

Permission Denied
- Ensure app has necessary permissions
- Check device settings for camera/photo access
Unsupported Format
- Verify image format is in supported list
- Try converting image to JPG/PNG format
Export Failed
- Check available storage space
- Ensure write permissions are granted
Slow Performance
- Large images may take longer to process
- Consider resizing images before analysis

Debug Mode

flutter run --debug

Contributing

Fork the repository
Create a feature branch
Make your changes
Add tests if applicable
Submit a pull request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

For issues and questions:

Create an issue in the repository
Check the troubleshooting section
Review the Flutter documentation for platform-specific issues