Guten AbendWie kann man skalierte Bilder speichern?
Ich versuche, die Größe der Bilder in Documents Directory zu speichern, um die Größe bei jedem Aufruf nicht zu ändern.
das Problem zu analysieren ist nur, wenn ich die folgende Zeile verwenden:
let jpgImageData = UIImageJPEGRepresentation (image, 1.0)
Es scheint, dass UIImageJPEGRepresentation die Änderungen an das Bild rückgängig gemacht und so speichert das Bild im gleichen Verhältnis.
Wer weiß, wie man das beheben kann?
Unter dem Code:
import UIKit
class ViewController: UIViewController {
@IBOutlet weak var imgView: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
let myImageName = "image_10001.jpg"
let imagePath = fileInDocumentsDirectory(filename: myImageName)
if let image = UIImage(named:"image_10001")?.resizedImage(newSize: UIScreen.main.bounds.size){
print("Image : \(image.size.height)")
_ = saveImage(image: image, path: imagePath)
}
if let loadedImage = loadImageFromPath(path: imagePath){
print("Screen: \(UIScreen.main.bounds.size.height)")
print("Image Size: \(loadedImage.size.height)")
// let image = UIImageJPEGRepresentation(loadedImage, 0.9)
// let imgRes = UIImage(data: image!)?.resizedImage(newSize: UIScreen.main.bounds.size)
////
// let load = loadedImage.resizedImage(newSize: UIScreen.main.bounds.size)
//
// print("Load: \(load.size.height)")
//
// _ = saveImage(image: load, path: imagePath)
//
imgView.image = loadedImage
//
// imgView.image = UIImage(data: image!)?.resizedImage(newSize: UIScreen.main.bounds.size)
}
// Do any additional setup after loading the view, typically from a nib.
}
func loadImageFromPath(path: String) -> UIImage? {
let image = UIImage(contentsOfFile: path)
if image == nil {
print("missing image at: \(path)")
}
print("Loading image from path: \(path)") // this is just for you to see the path in case you want to go to the directory, using Finder.
return image
}
func getDocumentsURL() -> URL {
let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
return documentsURL
}
func fileInDocumentsDirectory(filename: String) -> String {
let fileURL = getDocumentsURL().appendingPathComponent(filename)
return fileURL.path
}
func saveImage (image: UIImage, path: String) -> Bool{
print("Save")
let url = URL(fileURLWithPath: path)
// let pngImageData = UIImagePNGRepresentation(image)
let jpgImageData = UIImageJPEGRepresentation(image, 1.0) // if you want to save as JPEG
let img = UIImage(data:jpgImageData!)
//
print("SIMG: \(String(describing: img?.size.height))")
do {
_ = try jpgImageData?.write(to: url, options: .atomicWrite)
print("Save Success")
} catch let error {
print(error)
return false
}
return true
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
extension UIImage {
/// Returns a image that fills in newSize
func resizedImage(newSize: CGSize) -> UIImage {
// Guard newSize is different
guard self.size != newSize else { return self }
UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0);
self.draw(in: CGRect(x:0, y:0, width:newSize.width, height: newSize.height))
let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return newImage
}
/// Returns a resized image that fits in rectSize, keeping it's aspect ratio
/// Note that the new image size is not rectSize, but within it.
func resizedImageWithinRect(rectSize: CGSize) -> UIImage {
let widthFactor = size.width/rectSize.width
let heightFactor = size.height/rectSize.height
var resizeFactor = widthFactor
if size.height > size.width {
resizeFactor = heightFactor
}
let newSize = CGSize(width:size.width/resizeFactor, height:size.height/resizeFactor)
let resized = resizedImage(newSize: newSize)
return resized
}
var jpeg: Data? {
return UIImageJPEGRepresentation(self, 1) // QUALITY min = 0/max = 1
}
var png: Data? {
return UIImagePNGRepresentation(self)
}
}
extension Data {
var uiImage: UIImage? {
return UIImage(data: self)
}
}
Mögliche Duplikat [UIImageJpgRepresentation verdoppelt Bildauflösung] (http://stackoverflow.com/questions/43704615/uiimagejpgrepresentation-doubles-image-resolution) –