[CompressionService] compress 'image' to 'maxSize' size #swift3 #image #compression

CompressionService.swift

struct CompressionService {
  /**
   
   compress 'image' to 'maxSize' size
   
   - Parameter image:   The image to compress.
   - Parameter maxSize: The maximum size in MB to image.
   
   - Returns: A Data image with 'maxSize' applied.
 
   */
  static func compress(image: UIImage, maxSize: CGFloat) -> Data? {
    guard let imageSize = UIImageJPEGRepresentation(image, 1)?.count else { return nil }
    let compressionRate: CGFloat = (maxSize * 1024) / CGFloat(imageSize)
    
    return UIImageJPEGRepresentation(image, compressionRate)
  }
}