HEIC

UIImage+heicData.swift

extension UIImage {
  
  enum HEICError: Error {
    case heicNotSupported
    case cgImageMissing
    case couldNotFinalize
  }
  
  static var isHEICSupported: Bool = {
    let data = NSMutableData()
    return CGImageDestinationCreateWithData(data, AVFileType.heic as CFString,
                                            1, nil) != nil
  }()
  
  func heicData(compressionQuality: CGFloat) throws -> Data {
    let data = NSMutableData()
    guard let imageDestination =
      CGImageDestinationCreateWithData(data, AVFileType.heic as CFString, 1, nil)
      else {
        throw HEICError.heicNotSupported
    }
    
    guard let cgImage = self.cgImage else {
      throw HEICError.cgImageMissing
    }
    
    let options: NSDictionary = [kCGImageDestinationLossyCompressionQuality: compressionQuality]
    CGImageDestinationAddImage(imageDestination, cgImage, options)
    guard CGImageDestinationFinalize(imageDestination) else {
      throw HEICError.couldNotFinalize
    }
    
    return data as Data
  }
}