License

PhotoTrim is available under the MIT license. See the LICENSE file for more info.

PhotoTrim

PhotoTrim is a powerful and intuitive image cropping library designed for iOS applications. Built with user experience as the top priority, it offers smooth gesture handling and an elegant UI.

PhotoTrim is available under the MIT license. See the LICENSE file for more info.

PhotoTrim

PhotoTrim is a powerful

Key Features

PhotoTrim offers the following core functionalities:

Image Manipulation

• Intuitive pinch gestures for zoom control (supporting 0.5x to 4x magnification)
• Smooth pan gestures for image positioning
• Automatic image size adjustment and alignment

Crop Area

• Elegantly designed circular crop area
• Semi-transparent overlay to highlight the crop region
• Optional guidelines that can be enabled or disabled

Technical Features

• Support for iOS 11.0 and above
• Modern codebase written in Swift 5.0
• Responsive design using Auto Layout
• Memory-efficient image processing
• Thread-safe cropping operations

Installation

Swift Package Manager

Here's how to add PhotoTrim to your project in Xcode:

1. Select File > Add Packages... from the Xcode menu
2. Enter the following URL in the search field:

https://github.com/hooni0918/photoTrim.git

3. Select Version Rule:
   • Up to Next Major: 1.0.0
4. Click Add Package

Alternatively, you can add the dependency directly to your Package.swift file:

dependencies: [
    .package(url: "https://github.com/hooni0918/photoTrim.git", from: "1.0.0")
]

Detailed Usage Guide

Basic Setup

First, import PhotoTrim:

import PhotoTrim

Here's the basic setup:

class ViewController: UIViewController {
    private var trimView: PhotoTrimView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Initialize PhotoTrimView
        trimView = PhotoTrimView(frame: view.bounds)
        view.addSubview(trimView)
        
        // Setup Auto Layout
        trimView.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            trimView.topAnchor.constraint(equalTo: view.topAnchor),
            trimView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            trimView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            trimView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        ])
        
        // Set image
        if let image = UIImage(named: "example") {
            trimView.setImage(image)
        }
    }
}

Image Cropping

Here's how to obtain the cropped image:

@IBAction func cropButtonTapped(_ sender: Any) {
    if let croppedImage = trimView.getCroppedImage() {
        // Use the cropped image
        // Example: Save to photo library
        UIImageWriteToSavedPhotosAlbum(croppedImage, nil, nil, nil)
        
        // Or pass to another view controller
        let resultVC = ResultViewController()
        resultVC.image = croppedImage
        navigationController?.pushViewController(resultVC, animated: true)
    }
}

Customization

PhotoTrimView provides various customization options:

// Configure zoom levels
trimView.minimumZoomScale = 0.5  // Default: 1.0
trimView.maximumZoomScale = 4.0  // Default: 3.0

// Configure guidelines
trimView.shouldShowGuideLines = true  // Default: true

// Customize crop area style
trimView.cropAreaView.backgroundColor = UIColor.black.withAlphaComponent(0.6)

Advanced Usage

Implementing Delegate Pattern

To monitor image cropping status, implement PhotoTrimViewDelegate:

class ViewController: UIViewController, PhotoTrimViewDelegate {
    override func viewDidLoad() {
        super.viewDidLoad()
        trimView.delegate = self
    }
    
    func photoTrimViewDidBeginEditing(_ trimView: PhotoTrimView) {
        // Called when editing begins
    }
    
    func photoTrimViewDidEndEditing(_ trimView: PhotoTrimView) {
        // Called when editing ends
    }
    
    func photoTrimView(_ trimView: PhotoTrimView, didChangeCropRect rect: CGRect) {
        // Called when crop area changes
    }
}

Memory Management

Consider these points when handling large images:

override func viewDidDisappear(_ animated: Bool) {
    super.viewDidDisappear(animated)
    
    // Release image from memory
    trimView.imageView.image = nil
}

Troubleshooting

Common Issues

1. Image Not Displaying:

   • Verify image file is properly included in the project
   • Check image name accuracy in Asset Catalog

2. Unexpected Cropped Image Results:

   • Check original image orientation
   • Consider resizing if image is too large

3. Memory Warnings:

   • Implement image resizing for large images
   • Release unused images from memory

Performance Optimization Tips

1. Image Size Optimization:

extension UIImage {
    func optimizedForCropping() -> UIImage {
        let maxDimension: CGFloat = 2048
        if size.width > maxDimension || size.height > maxDimension {
            let ratio = size.width / size.height
            let newSize: CGSize
            if ratio > 1 {
                newSize = CGSize(width: maxDimension, height: maxDimension / ratio)
            } else {
                newSize = CGSize(width: maxDimension * ratio, height: maxDimension)
            }
            let format = UIGraphicsImageRendererFormat()
            format.scale = 1
            let renderer = UIGraphicsImageRenderer(size: newSize, format: format)
            return renderer.image { _ in
                draw(in: CGRect(origin: .zero, size: newSize))
            }
        }
        return self
    }
}

2. Image Loading Optimization:

func loadImage() {
    DispatchQueue.global(qos: .userInitiated).async {
        if let image = UIImage(named: "example")?.optimizedForCropping() {
            DispatchQueue.main.async {
                self.trimView.setImage(image)
            }
        }
    }
}

Contributing

To contribute to PhotoTrim:

1. Issue Submission:

   • Bug reports
   • Feature requests
   • Documentation improvements

2. Pull Requests:

   • Follow code style guidelines
   • Include test coverage
   • Provide detailed change descriptions

License

PhotoTrim is available under the MIT license. See the LICENSE file for details.

Contact

Please submit questions or issues through GitHub Issues.

Version History

• 1.0.0
  • Initial release
  • Basic image cropping functionality
  • Circular crop area support
  • Gesture-based manipulation

Acknowledgments

This project was inspired by the following open-source projects:

• YPImagePicker
• TOCropViewController

Thank you for choosing our library. We are committed to continuously improving the iOS development experience.