Smart Focus Image #

A Flutter package that automatically crops images to focus on detected faces using Google ML Kit. Perfect for profile pictures, avatars, and any scenario where you need to ensure faces are properly centered and visible in cropped images.

Features #

• 🎯 Automatic Face Detection: Uses Google ML Kit to detect faces in images
• 🖼️ Smart Cropping: Automatically crops images to focus on detected faces instead of center-cropping
• 👥 Multiple Faces Support: Option to detect and display all faces or just the main (largest) face
• ⚡ Fast Performance: Optimized for quick face detection and image processing
• 🎨 Customizable: Supports custom placeholders and sizing

Getting Started #

Prerequisites #

• Flutter SDK (>=3.0.0)
• Dart SDK (>=3.0.0)

Installation #

Add this to your package's pubspec.yaml file:

dependencies:
  smart_focus_image: ^1.0.0

Then run:

flutter pub get

Platform Setup #

Android

Add the following to your android/app/build.gradle:

android {
    defaultConfig {
        minSdkVersion 21
    }
}

iOS

Add the following to your ios/Podfile:

platform :ios, '12.0'

Then run:

cd ios && pod install

Usage #

Basic Usage (Single Face) #

import 'package:smart_focus_image/smart_focus_image.dart';
import 'dart:io';

SmartFocusImage(
  imageFile: File('path/to/image.jpg'),
  width: 200,
  height: 200,
  placeholder: CircularProgressIndicator(),
)

Multiple Faces #

To detect and display all faces in an image:

SmartFocusImage(
  imageFile: File('path/to/image.jpg'),
  width: 200,
  height: 200,
  returnAllFaces: true, // Set to true to show all detected faces
  placeholder: CircularProgressIndicator(),
)

Complete Example #

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:smart_focus_image/smart_focus_image.dart';

class MyWidget extends StatelessWidget {
  final File imageFile;

  const MyWidget({required this.imageFile});

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        // Show only the main face
        SmartFocusImage(
          imageFile: imageFile,
          width: 200,
          height: 200,
          placeholder: const Center(child: Text("Analyzing...")),
        ),
        
        const SizedBox(height: 20),
        
        // Show all detected faces
        SmartFocusImage(
          imageFile: imageFile,
          width: 200,
          height: 200,
          returnAllFaces: true,
          placeholder: const Center(child: Text("Analyzing...")),
        ),
      ],
    );
  }
}

Parameters #

How It Works #

1. The package uses Google ML Kit's face detection to identify faces in the image
2. Faces are sorted by size (largest first) to determine the "main" face
3. Each detected face is cropped with a 20% padding around the bounding box
4. The cropped region is then displayed at the specified width and height

Example App #

Check out the example folder for a complete working example that demonstrates:

• Single face detection
• Multiple faces detection
• Toggle between modes
• Comparison with standard center cropping

License #

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

Contributing #

Contributions are welcome! Please feel free to submit a Pull Request.

Issues #

If you encounter any issues or have feature requests, please file them on the GitHub issue tracker.