Is there any way to check if UIImage has been unpacked?

Question

I am sure that most of you have been forced to decompress in the background thread to increase rendering performance. My question is if there is a way to check if the image has been unpacked.

Answer 1

This helped me verify that the image was decompressed or not using the technique below. This is a simple code to understand: -

import UIKit class ViewController: UIViewController { var compressedImage:NSString? var decompressedImage:NSString? override func viewDidLoad() { super.viewDidLoad() let image = compressImage() var imageView = UIImageView(image: image) //self.view.addSubview(imageView) let decompressImage = deCompressImage(image: image) let imageData = Data(UIImagePNGRepresentation(decompressImage)! ) print("***** Size after decompred \(imageData.description) **** ") imageView = UIImageView(image: decompressImage) decompressedImage = imageData.description as NSString? let decompressed = checkImageBeenDecompressed(decompressedImage: decompressedImage!, compressedImage: compressedImage!) print(decompressed) //self.view.addSubview(imageView) } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() // Dispose of any resources that can be recreated. } func checkImageBeenDecompressed(decompressedImage:NSString , compressedImage:NSString) -> Bool { let decompressedSize = Int( decompressedImage.getNumFromString()! ) let compressedSize = Int (compressedImage.getNumFromString()! ) if( decompressedSize! > compressedSize! ) { print("Image has been decompressed") return true } print("Image has not been decompressed") return false } func compressImage() -> UIImage { let oldImage = UIImage(named: "background.jpg") var imageData = Data(UIImagePNGRepresentation(oldImage!)! ) print("***** Original Uncompressed Size \(imageData.description) **** ") imageData = UIImageJPEGRepresentation(oldImage!, 0.025)! print("***** Compressed Size \(imageData.description) **** ") compressedImage = imageData.description as NSString? let image = UIImage(data: imageData) return image! } func deCompressImage(image:UIImage) -> UIImage { UIGraphicsBeginImageContextWithOptions(image.size, true, 0) image.draw(at: CGPoint.zero) let decompressedImage = UIGraphicsGetImageFromCurrentImageContext() UIGraphicsEndImageContext() return decompressedImage! } } extension NSString { func getNumFromString() -> String? { var numberString: NSString? let thisScanner = Scanner(string: self as String) let numbers = NSCharacterSet(charactersIn: "0123456789") thisScanner.scanUpToCharacters(from: numbers as CharacterSet, into: nil) thisScanner.scanCharacters(from: numbers as CharacterSet, into: &numberString) return numberString as? String; } } 

Demo version