If we have image imageName.jpg in Assets.xcassets and let's put that image in UIImage like this:
let imageForExif: UIImage = UIImage(named: "imageName.jpg")!
How we can get (extract) Exif data from imageForExif using Swift?
Try this...
if let imageData = UIImageJPEGRepresentation(imageForExif, 1.0) {
let imageCFData = imageData as CFData
if let cgImage = CGImageSourceCreateWithData(imageCFData, nil), let metaDict: NSDictionary = CGImageSourceCopyPropertiesAtIndex(cgImage, 0, nil) {
let exifDict: NSDictionary = metaDict.object(forKey: kCGImagePropertyExifDictionary) as! NSDictionary
print(exifDict)
}
}
But you may have very limited data available. Hope it helps.
Related
Am creating an application for image share related things. Here my requirement is I have to store some custom information(Name, PhoneNumber, Price) into the Image Metadata and retrieve it back.
I use UIImagePickerController to capture the image and set my information into the image metadata in UIImagePickerControllerDelegate like below mentioned:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
picker.dismiss(animated: true, completion: nil)
let profileImage = info[UIImagePickerControllerOriginalImage] as? UIImage
let imageData: Data = UIImageJPEGRepresentation(profileImage!, 1)!
let cgImgSource: CGImageSource = CGImageSourceCreateWithData(imageData as CFData, nil)!
let uti: CFString = CGImageSourceGetType(cgImgSource)!
let dataWithExif: NSMutableData = NSMutableData(data: imageData)
let destination: CGImageDestination = CGImageDestinationCreateWithData((dataWithExif as CFMutableData), uti, 1, nil)!
let imageProoperties = CGImageSourceCopyPropertiesAtIndex(cgImgSource, 0, nil)! as NSDictionary
let mutable: NSMutableDictionary = imageProoperties.mutableCopy() as! NSMutableDictionary
let EXIFDictionary: NSMutableDictionary = (mutable[kCGImagePropertyExifDictionary as String] as? NSMutableDictionary)!
print("Before Modification: \(EXIFDictionary)")
EXIFDictionary[kCGImagePropertyExifUserComment as String] = "\(self.m_NameTxtFd.text!):\(self.m_PhoneNumberTxtFd.text!):\(self.m_PriceTxtFd.text!)"
mutable[kCGImagePropertyExifDictionary as String] = EXIFDictionary
CGImageDestinationAddImageFromSource(destination, cgImgSource, 0, (mutable as CFDictionary))
CGImageDestinationFinalize(destination)
let testImage: CIImage = CIImage(data: dataWithExif as Data, options: nil)!
let newProperties: NSDictionary = testImage.properties as NSDictionary
print("After Modification : \(newProperties)") //Here I Got My Information is Stored Successfully
self.m_ImgView.image = self.convert(cmage: testImage)
self.saveImageDocumentDirectory()
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
picker.dismiss(animated: true, completion: nil)
}
Now am going to save the image in NSDocumentDirectory like below mentioned:
func saveImageDocumentDirectory(){
let fileManager = FileManager.default
let paths = (NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as NSString).appendingPathComponent("apple.jpg")
let image = self.m_ImgView.image
print(paths)
let imageData = UIImageJPEGRepresentation(image!, 0.5)
fileManager.createFile(atPath: paths as String, contents: imageData, attributes: nil)
}
Now am going to fetch the stored image in another view controller like below mentioned:
func getImage(){
let fileManager = FileManager.default
let imagePAth = (self.getDirectoryPath() as NSString).appendingPathComponent("apple.jpg")
print(imagePAth)
if fileManager.fileExists(atPath: imagePAth){
self.m_ImgView.image = UIImage(contentsOfFile: imagePAth)
self.fetchImageDetails()
}else{
print("No Image")
}
}
I successfully got the image and now I have to fetch the information from image metadata like below mentioned:
func fetchImageDetails() {
let profileImage = self.m_ImgView.image!
let ciImage: CIImage = CIImage(cgImage: profileImage.cgImage!)
let newProperties: NSDictionary = ciImage.properties as NSDictionary
}
But issue is the information is null in image property.
Please guide me to retrieve the custom information from stored Image.
First create NSMutableDictionary and set value to NSMutableDictionary when you set value to then you don't need to set again to metadata you directly assign to NSMutableDictionary to Metada.
let metadata = info[UIImagePickerControllerMediaMetadata] as? NSMutableDictionary
let exifData = NSMutableDictionary()
let metaStr = "\(self.m_NameTxtFd.text!),\(self.m_PhoneNumberTxtFd.text!),\(self.m_PriceTxtFd.text!)"
exifData.setValue(metaStr, forKey: kCGImagePropertyExifDictionary as String)
metadata = exifData
fileManager.requestImageData(for: fetchResult.object(at: i) as PHAsset, options: requestOptions, resultHandler: { (imagedata, dataUTI, orientation, info ) in
if let info = info {
if info.keys.contains(NSString(string: "PHImageFileURLKey")) {
path = info[NSString(string: "PHImageFileURLKey")] as? NSURL
size = (imagedata! as NSData).length
self.name = PHAssetResource.assetResources(for:fetchResult.object(at: i)).first?.originalFilename
self.imageData = imagedata
}
}
})
I've an image (captureImage) which is taken by camera and resized. I use UIImageJPEGRepresentation to compress image, after the compression, image's size is increased. Is it normal behaviour or I'm doing compression/resizing in wrong way?
if let image = captureImage {
print(image.size) // (700, 700)
let compressedImageData = UIImageJPEGRepresentation(image, 0.3)!
let compressedImage = UIImage(data: compressedImageData)!
print(compressedImage.size) // (3024, 3024)
}
Yes this code is for image compression
let compressedImageData = UIImageJPEGRepresentation(image, 0.3)!
One way for getting the file size is by saving into document directory.
For example -
let filePath = fileURL
var fileSize : UInt64
do {
//return [FileAttributeKey : Any]
let attr = try FileManager.default.attributesOfItem(atPath: filePath.path)
fileSize = attr[FileAttributeKey.size] as! UInt64
//if you convert to NSDictionary, you can get file size old way as well.
let dict = attr as NSDictionary
fileSize = dict.fileSize()
print(fileSize)
} catch {
print("Error: \(error)")
}
//To encode I found the following example. I don't know if it works yet
#IBAction func exitImageViewController(seque:UIStoryboardSegue){
let imageController = seque.destination as! MyImageViewController
let myView = imageController.imageView
imageData = UIImagePNGRepresentation((myView?.image!)!)
imageString = imageData?.base64EncodedString()
// Is this swift code correct?
//I cannot find an example of decoding String back to UIImage
The code you posted looks fine. To encode back you can do this:
let data = Data(base64Encoded: imageString!)
let img = UIImage(data: data!)
My iOS app (Swift 3) needs to important images from other apps using an Action Extension. I'm using the standard Action Extension template code which works just fine for apps like iOS Mail and Photos where the image shared is a URL to a local file. But for certain apps where the image being shared is the actual image data itself, my action extension code isn't getting the image.
for item: Any in self.extensionContext!.inputItems {
let inputItem = item as! NSExtensionItem
for provider: Any in inputItem.attachments! {
let itemProvider = provider as! NSItemProvider
if itemProvider.hasItemConformingToTypeIdentifier(kUTTypeImage as String) { //we'll take any image type: gif, png, jpg, etc
// This is an image. We'll load it, then place it in our image view.
weak var weakImageView = self.imageView
itemProvider.loadItem(forTypeIdentifier: kUTTypeImage as String, options: nil, completionHandler: { (imageURL,
error) in
OperationQueue.main.addOperation {
if let strongImageView = weakImageView {
if let imageURL = imageURL as? NSURL {
strongImageView.image = UIImage(data: NSData(contentsOf: imageURL as URL)! as Data)
let imageData = NSData(contentsOf: imageURL as URL)! as Data
self.gifImageView.image = UIImage.gif(data: imageData)
let width = strongImageView.image?.size.width
let height = strongImageView.image?.size.height
.... my custom logic
}
}
For reference, I reached out to the developer for one of the apps where things aren't working and he shared this code on how he is sharing the image to the Action Extension.
//Here is the relevant code. At this point the scaledImage variable holds a UIImage.
var activityItems = Array<Any?>()
if let pngData = UIImagePNGRepresentation(scaledImage) {
activityItems.append(pngData)
} else {
activityItems.append(scaledImage)
}
//Then a little later it presents the share sheet:
let activityVC = UIActivityViewController(activityItems: activityItems,applicationActivities: [])
self.present(activityVC, animated: true, completion: nil)
Figured it out thanks to this post which explains the challenge quite well https://pspdfkit.com/blog/2017/action-extension/ . In summary, we don't know if the sharing app is giving us a URL to an existing image or just raw image data so we need to modify the out of the box action extension template code to handle both cases.
for item: Any in self.extensionContext!.inputItems {
let inputItem = item as! NSExtensionItem
for provider: Any in inputItem.attachments! {
let itemProvider = provider as! NSItemProvider
if itemProvider.hasItemConformingToTypeIdentifier(kUTTypeImage as String) { //we'll take any image type: gif, png, jpg, etc
// This is an image. We'll load it, then place it in our image view.
weak var weakImageView = self.imageView
itemProvider.loadItem(forTypeIdentifier: kUTTypeImage as String, options: nil, completionHandler: { (imageURL,
error) in
OperationQueue.main.addOperation {
if let strongImageView = weakImageView {
if let imageURL = imageURL as? NSURL {
strongImageView.image = UIImage(data: NSData(contentsOf: imageURL as URL)! as Data)
let imageData = NSData(contentsOf: imageURL as URL)! as Data
self.gifImageView.image = UIImage.gif(data: imageData)
let width = strongImageView.image?.size.width
let height = strongImageView.image?.size.height
.... my custom logic
}
else
guard let imageData = imageURL as? Data else { return } //can we cast to image data?
strongImageView_.image = UIImage(data: imageData_)
//custom logic
}
I want to display image metadata using UIImagePickerController in Swift.
where the image is been selected from gallery and would be displayed in the imageView along with the meta data such as PixelHeight,PixelWidth,PixelXDimension,PixelYDimension,Coordinates,Size,Date Created and Imagename.
At first, you can get info[UIImagePickerControllerReferenceURL] from UIImagePickerController. Then you can do things like the following:
let assetURL = info[UIImagePickerControllerReferenceURL] as! NSURL
let asset = PHAsset.fetchAssetsWithALAssetURLs([assetURL], options: nil)
guard let result = asset.firstObject where result is PHAsset else {
return
}
let imageManager = PHImageManager.defaultManager()
imageManager.requestImageDataForAsset(result as! PHAsset, options: nil, resultHandler:{
(data, responseString, imageOriet, info) -> Void in
let imageData: NSData = data!
if let imageSource = CGImageSourceCreateWithData(imageData, nil) {
let imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, nil)! as NSDictionary
//now you have got meta data in imageProperties, you can display PixelHeight, PixelWidth, etc.
}
})