UIImageExtensions

Collection of UIImage utility methods to ease integration with media frameworks.

• Requirements
• Installation
• Usage
  • Core Video pixel buffer
  • Core Media sample buffer
  • UIImage from Base64 encoded string

Requirements

• iOS 13.0, macOS 10.15
• Swift 5.2

Installation

Use Xcode's built-in Swift Package Manager:

• Open Xcode
• Click File -> Swift Packages -> Add Package Dependency
• Paste package repository https://github.com/frolovilya/UIImageExtensions.git and press return
• Configure dependency version settings
• Import module to any file using import UIImageExtensions

Usage

import UIKit
import UIImageExcensions

// obtain some UIImage instance
let myImage: UIImage = #imageLiteral(resourceName: "MyImage")

Core Video pixel buffer

Copies image data to CVPixelBuffer.

// func toPixelBuffer() -> CVPixelBuffer?

let buffer: CVPixelBuffer? = myImage.toPixelBuffer()

And back from CVPixelBuffer to UIImage. Provide optional orientation parameter to rotate image.

// func toImage(orientation: CGImagePropertyOrientation = .up) -> UIImage?

let backToImage: UIImage? = buffer?.toImage(orientation: .left)

Core Media sample buffer

Actually wraps CVPixelBuffer to CMSampleBuffer with additional sample timing information.

With provided frameIndex and framesPerSecond the following timing rules apply:

• Sample duration (seconds): 1 / framesPerSecond
• Sample start time: frameIndex / framesPerSecond

Assuming that timing starts from zero.

// func toSampleBuffer(frameIndex: Int = 0, framesPerSecond: Double = 24) -> CMSampleBuffer?

let buffer: CMSampleBuffer? = myImage.toSampleBuffer(frameIndex: 1, framesPerSecond: 24)

Create UIImage from Base64 encoded string

Convenience static initializer to get UIImage instance right from Base64 encoded string.

// static func fromBase64String(_ base64String: String) -> UIImage?

let decodedImage: UIImage? = UIImage.fromBase64String("data:image/jpeg;base64,/9j/4AAQSkZJ...")

And property containing Base64 string of a UIImage instance.

// var base64String: String?

let imageAsString: String? = myImage.base64String