Hi, I’m working on a photo backup app.
I track the PHAsset localIdentifier to determine which photos have been backed up and which haven’t.
Recently, I’ve noticed that two users seem to have experienced the localIdentifier changes after transferring data to a new iPhone using Quick Start.
Additionally, others on StackOverflow have mentioned that the localIdentifier sometimes changes after updating the iOS version.
https://stackoverflow.com/questions/40094728/phobject-localidentifier-reliability
I’d like to confirm the reliability of the localIdentifier after an iOS version upgrade or device transfer.
Can I continue using these locally stored localIdentifiers?
Or is there another recommended approach, such as using PHCloudIdentifier?
Photos & Camera
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I would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model.
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
3D Graphics
Swift Playground
Object Capture
I am new here and would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model. I am able to create from LiDAR scanning 3D mesh and .OBJ file but can not generate .MTL and .JPEG for a texture of 3D model.
Hello, my company is developing a product that will send data to/from the phone over cable and Wi-Fi. I have three questions:
Do we need an MFi authentication chip in our product if we plan to send video and commands to the iPhone/iPad over USB or Lightning cable?
Likewise, do we need an MFI authentication chip for communication over Wi-Fi? (Informal research suggests that the answer is no to this one.)
And, do we even still need MFI certification at all for Wi-Fi comms? (We are not using HomeKit.)
Thank you!
Topic:
Media Technologies
SubTopic:
Photos & Camera
I want to modify the photo's exif information, which means putting the original image in through CGImageDestinationAddImageFromSource, and then adding the modified exif information to a place called properties.
Here is the complete process:
static func setImageMetadata(asset: PHAsset, exif: [String: Any]) {
let options = PHContentEditingInputRequestOptions()
options.canHandleAdjustmentData = { (adjustmentData) -> Bool in
return true
}
asset.requestContentEditingInput(with: options, completionHandler: { input, map in
guard let inputNN = input else {
return
}
guard let url = inputNN.fullSizeImageURL else {
return
}
let output = PHContentEditingOutput(contentEditingInput: inputNN)
let adjustmentData = PHAdjustmentData(formatIdentifier: AppInfo.appBundleId(), formatVersion: AppInfo.appVersion(), data: Data())
output.adjustmentData = adjustmentData
let outputURL = output.renderedContentURL
guard let source = CGImageSourceCreateWithURL(url as CFURL, nil) else {
return
}
guard let dest = CGImageDestinationCreateWithURL(outputURL as CFURL, UTType.jpeg.identifier as CFString, 1, nil) else {
return
}
CGImageDestinationAddImageFromSource(dest, source, 0, exif as CFDictionary)
let d = CGImageDestinationFinalize(dest)
// d is true, and I checked the content of outputURL, image has been write correctly, it could be convert to UIImage and image is ok.
PHPhotoLibrary.shared().performChanges {
let changeReq = PHAssetChangeRequest(for: asset)
changeReq.contentEditingOutput = output
} completionHandler: { succ, err in
if !succ {
print(err) // 3303 here, always!
}
}
})
}
I set the device format and colorspace to Apple Log and turn off the HDR, why the movie output is still in HDR format rather than ProRes Log?
Full runnable demo here:
https://github.com/SpaceGrey/ColorSpaceDemo
session.sessionPreset = .inputPriority
// get the back camera
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: .video, position: .back)
backCamera = deviceDiscoverySession.devices.first!
try! backCamera.lockForConfiguration()
backCamera.automaticallyAdjustsVideoHDREnabled = false
backCamera.isVideoHDREnabled = false
let formats = backCamera.formats
let appleLogFormat = formats.first { format in
format.supportedColorSpaces.contains(.appleLog)
}
print(appleLogFormat!.supportedColorSpaces.contains(.appleLog))
backCamera.activeFormat = appleLogFormat!
backCamera.activeColorSpace = .appleLog
print("colorspace is Apple Log \(backCamera.activeColorSpace == .appleLog)")
backCamera.unlockForConfiguration()
do {
let input = try AVCaptureDeviceInput(device: backCamera)
session.addInput(input)
} catch {
print(error.localizedDescription)
}
// add output
output = AVCaptureMovieFileOutput()
session.addOutput(output)
let connection = output.connection(with: .video)!
print(
output.outputSettings(for: connection)
)
/*
["AVVideoWidthKey": 1920, "AVVideoHeightKey": 1080, "AVVideoCodecKey": apch,<----- prores has enabled.
"AVVideoCompressionPropertiesKey": {
AverageBitRate = 220029696;
ExpectedFrameRate = 30;
PrepareEncodedSampleBuffersForPaddedWrites = 1;
PrioritizeEncodingSpeedOverQuality = 0;
RealTime = 1;
}]
*/
previewSource = DefaultPreviewSource(session: session)
queue.async {
self.session.startRunning()
}
}
Hi,
Currently I am developing a 3D reconstruction project.
Which requires images to be distortion-free (rectilinear) and with known intrinsics.
The session I am developing on is a builtInDualWideCamera, with isGeometricDistortionCorrectionEnabled set to false to be able to get the intrinsic matrix of the images, isVirtualDeviceConstituentPhotoDeliveryEnabled set to true and isAutoVirtualDeviceFusionEnabled set to false to get both images and isCameraCalibrationDataDeliveryEnabled set to true to actually get the calibration data.
The distortion correction parameters such as lensDistortionLookupTable are used.
The 42 coefficients mapping array is used as described in the AVCameraCalibrationData header file. A simple piecewise linear interpolation.
There are two questions I would like to get support on:
A way to set the calibration parameters in each image.
I have an approach that sets the parameters in the kCGImagePropertyExifDictionary -> "UserComment". Is there a better approach to write calibration parameter data into the images? I feel like this is a bit dirty and there might be a better and neat approach.
For the ultra-wide angle camera's images, the lensDistortionLookupTable contains several zeros at the end of the array.
For example (last 10 elements are zero):
"LensDistortionLookupTable":"0.000000000000000,0.000349554029526,0.001385628827848,0.003071037586778,... ,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000"
The problem comes when the complete array is used to correct the image (including zeros), the end result is a wrapped-like-circle image close to the edges of it which is completely wrong.
In contrast, if the LensDistortionLookupTable is used without the last zeros and the new size accommodated the image looks better (although not as rectilinear as if you take the image from the iPhone's camera app), but definitely less distorted.
Including zeros (full array):
Excluding zeros (array size changed):
Am I missing an important point in the usage of the lensDistortionLookupTable where this case is addressed (zeros at the end)?
What is the criteria to shrink/exclude elements of the array?
Any advice is very much welcome.
Is it possible to use the AVExternalStorageDevice to access external storage from a connected camera or usb drive (via USB C or Lightning connector) on an iPad/iPhone.
I have tested the following code on an iPhone 14 (iOS 18.1.1) and an iPad Gen 10 (18.3.1), and both return false for:
// returns false on iPhone 14, iPad gen 10
print(AVExternalStorageDeviceDiscoverySession.isSupported)
The following code returns null, when I try to access the external storage discovery session.
// returns null on iOS devices
print(AVExternalStorageDeviceDiscoverySession.shared)
The following returns false, without displaying a permission dialog:
AVExternalStorageDevice.requestAccess(completionHandler: { (granted: Bool) in
// returns false with no permission dialog
print(granted);
What type of iOS devices are supported by AVExternalStorageDeviceDiscoverySession?
What situations has it been used for (e.g. connecting to Camera via the external storage protocol, accessing photos from a SD card with an adapter, accessing photos from usb drive).
Is there are sample code for using the AV External Storage api?
I found that when the development tool above Xcode16 ran my app, I opened the suspended inscription function, and then opened the system camera, the content in the suspended window would not be displayed, and the suspended window would have a black screen. However, this phenomenon does not appear on Xcode15.4 development tools, it is the same code, I do not know why
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Swift Packages
App Clips
Developer Tools
iOS
Hi
This is one of our top crashes. It does not contain any of our code in the stacktrace and we can't reproduce it. Those points make this crash very hard to understand and fix. We know that most of the crashes are happening on iPhone 13 with iOS 18.x.x. Also we see that a lot of cases happen when app goes into background (stacktrace contains -[UIApplication _applicationDidEnterBackground]).
2025-03-04_16-06-00.3670_-0500-6a273c7d5da97f098b5cc24898bb9761dc45208e.crash
2025-03-04_20-21-08.6609_-0500-2c08f640900f8a62c4f8a4f6f2a61feb052e66dd.crash
2025-03-04_20-46-27.7138_+0000-4d7ea89b1b564eda22ca63e708f7ad3909c7b768.crash
I am following the Apple sample code and trying to add a manual focus lens position slider:
@available(iOS 18.0, *)
private func addCameraControls() {
if !self.session.controls.isEmpty {
for control in self.session.controls {
self.session.removeControl(control)
}
}
self.cameraControlFocusSlider = nil
//Focus Slider
if self.videoDevice!.isLockingFocusWithCustomLensPositionSupported {
self.cameraControlFocusSlider = AVCaptureSlider("Focus", symbolName: "dot.square", in: 0.0...1.0)
self.cameraControlFocusSlider!.setActionQueue(self.sessionQueue) { focusValue in
//Do manual focus
}
if self.session.canAddControl(self.cameraControlFocusSlider!) {
self.session.addControl(self.cameraControlFocusSlider!)
}
}
}
So there are these AVCaptureSessionControlsDelegate methods:
final func sessionControlsDidBecomeActive(_ session: AVCaptureSession) {
print ("sessionControlsDidBecomeActive")
}
final func sessionControlsWillEnterFullscreenAppearance(_ session: AVCaptureSession) {
print ("sessionControlsWillEnterFullscreenAppearance")
}
final func sessionControlsWillExitFullscreenAppearance(_ session: AVCaptureSession) {
print ("sessionControlsWillExitFullscreenAppearance")
}
final func sessionControlsDidBecomeInactive(_ session: AVCaptureSession) {
print ("sessionControlsDidBecomeInactive")
}
So when self.cameraControlFocusSlider is presented, I have to show the current value of the lense position. Lens position can change from auto focus and also from manual focus by the user using the app UI. Is there a way to see if self.cameraControlFocusSlider is active or being used?
Please note that I will have more than one AVCaptureSlider in the final code.
I’m developing a hybrid app (WebView / Turbo Native) that uses getUserMedia to access the back camera for a PPG/heart rate measurement feature (the user places their finger on the camera).
Problem: Even when I specify constraints like:
{
video: {
deviceId: '...',
facingMode: { exact: 'environment' },
advanced: [{ zoom: 1.0 }]
},
audio: false
}
On iPhone 15 (iOS 18), iOS unexpectedly switches between the wide, ultra-wide, and telephoto lenses during the measurement.
This breaks the heart rate detection, and it forces the user to move their finger in the middle of the measurement.
Question: Is there any way, via getUserMedia/WebRTC, to force iOS to use only the wide-angle lens and prevent automatic lens switching?
I know that with AVFoundation (Swift) you can pick .builtInWideAngleCamera, but I’m hoping to avoid building a custom native layer and would prefer to stick with WebView/JavaScript if possible to save time and complexity.
Any suggestions, workarounds, or updates from Apple would be greatly appreciated!
Thanks a lot!
I want to create a Live Photo. The project includes a .jpg image and a .mov video (2 seconds).
Two permissions in xcode have been added:
Privacy - Photo Library Usage Description
Privacy - Photo Library Additions Usage Description
Simulate: iphone 16, ios 18.3
The codes in ContentView.swift :
private func saveLivePhoto(imageURL: URL, videoURL: URL, completion: @escaping (Bool, Error?) -> Void) {
PHPhotoLibrary.shared().performChanges {
let creationRequest = PHAssetCreationRequest.forAsset()
let options = PHAssetResourceCreationOptions()
options.shouldMoveFile = false
creationRequest.addResource(with: .photo, fileURL: imageURL, options: options)
creationRequest.addResource(with: .pairedVideo, fileURL: videoURL, options: options)
} completionHandler: { success, error in
DispatchQueue.main.async {
print(error)
completion(success, error)
}
}
}
guard let imageURL = Bundle.main.url(forResource: "livephoto", withExtension: "jpeg"),
let videoURL = Bundle.main.url(forResource: "livephoto", withExtension: "mov") else {
showAlertMessage(title: "error", message: "cant find Live Photo ")
return
}
print("imageURL: \(imageURL)")
print("videoURL: \(videoURL)")
saveLivePhoto(imageURL: imageURL, videoURL: videoURL) { success, error in
if success {
xxxxx
} else {
xxxxx
}
}
Really need help, thanks
If new photo is added to library and app is not running in foreground or was not opened after the new photo was added but the app is having full access to gallery, can it access, read the new photo - If the app is not specifically a cloud syncing app, can it have this attached function, suppose it is a game app or beauty camera app?
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Privacy
PhotoKit
Background Tasks
Background Assets
Hi all,
I'm using Apple Sample Code below to create application using dockkit.
"Controlling a DockKit accessory using your camera app"
https://developer.apple.com/documentation/dockkit/controlling-a-dockkit-accessory-using-your-camera-app?changes=_8
I used vision hand recognition and put the observation data to dockAccessory.track, but Belkin or Insta360 devices never move on iPhone 16 Pro Max with iOS 18.3.
If I use other functions like face search (system tracking) in the app, those work ok.
I used Belkin and Insta360 Flow 2 Pro to reproduce the problem.
My friend is also saying that the custom tracking feature was working fine on the OS 18 beta, but on recent iOS 18.3 that feature does not work.
If I can get the iOS 18.0 beta then we can test that feature. But I cannot revert my iOS from 18.3 to the iOS 18.0 Beta.
Regards,
TO
On some devices, loadFileRepresentation(forTypeIdentifier: completionHandler) take a loong time(about two minute) to callback result for some large video(about 200 MB, take by device camera).
environment:
Model: iPhone 12
Model Number: MGGM3CH/A
iOS Version: 18.3.2
PHPickerResult.NSItemProvider.loadFileRepresentation()
// import PhotosUI
func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
picker.dismiss(animated: true, completion: nil)
guard let provider = results.last?.itemProvider else { return }
guard provider.hasItemConformingToTypeIdentifier(UTType.movie.identifier) else {
return
}
Task {
provider.loadFileRepresentation(forTypeIdentifier: UTType.movie.identifier) { url, error in
guard let url = url else {
return
}
// Do some stuff...
}
}
}
ps: I also try some other function, eg: provide.loadItem(forTypeIdentifier:), but not work too.
On some devices, when i select the same media multiple times, the data by` loadFileRepresentation(forTypeIdentifier: completionHandler) ` returned is different(data.count is not equal).
environment:
* Model: iPhone 12
* Model Number: MGGM3CH/A
* iOS Version: 18.3.2
```Swift
// import PhotosUI
func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
picker.dismiss(animated: true, completion: nil)
guard let provider = results.last?.itemProvider else { return }
guard provider.hasItemConformingToTypeIdentifier(UTType.movie.identifier) else {
return
}
Task {
provider.loadFileRepresentation(forTypeIdentifier: UTType.movie.identifier) { url, error in
guard let url = url else {
return
}
if let data = try? Data(contentsOf: url) {
print("data count is: \(data.count)")
}
}
}
}
```
ps: I also try some other function, eg: ` provide.loadItem(forTypeIdentifier:)`, but not work too.
I'm developing a tennis ball tracking feature using Vision Framework in Swift, specifically utilizing VNDetectedObjectObservation and VNTrackObjectRequest.
Occasionally (but not always), I receive the following runtime error:
Failed to perform SequenceRequest: Error Domain=com.apple.Vision Code=9 "Internal error: unexpected tracked object bounding box size" UserInfo={NSLocalizedDescription=Internal error: unexpected tracked object bounding box size}
From my investigation, I suspect the issue arises when the bounding box from the initial observation (VNDetectedObjectObservation) is too small. However, Apple's documentation doesn't clearly define the minimum bounding box size that's considered valid by VNTrackObjectRequest.
Could someone clarify:
What is the minimum acceptable bounding box width and height (normalized) that Vision Framework's VNTrackObjectRequest expects?
Is there any recommended practice or official guidance for bounding box size validation before creating a tracking request?
This information would be extremely helpful to reliably avoid this internal error.
Thank you!
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
ML Compute
Machine Learning
Camera
AVFoundation
Hi,
Could anybody share the full list of supported Predicate keys for the PHFetchOptions?
I'm aware of the list that is posted in the documentation:
https://developer.apple.com/documentation/photos/phfetchoptions
However I have reason to believe that this is not an exhaustive list and there also seem to be mistakes in this doc. i.e. isFavorite does not work but favorite does.
Through some experimentation I also found that this works:
NSPredicate(format: "adjustmentFormatIdentifier == 'com.pixelmatorteam.touch.x.photo.PhotosAdjustmentData.EmbeddedSlimSidecarFileInfo.compressed'")
even though adjustmentFormatIdentifier is not listed as a supported key.
Are there other secret keys that you are aware of?
Specifically I want to filter a fetch result for edited items. Something like this:
NSPredicate(format: "hasAdjustments == true")
(I tried this, doesn't work)
The native Photos app has such a filter which leads me to believe that there probably is a key for this:
If one of the Framework Developers reads this: Could you please update the documentation page with this information?
Finally if there really aren't any more secret keys, is there a way to achieve this with adjustmentFormatIdentifier? I have tried a bunch of stuff already like adjustmentFormatIdentifier != nil but for some reason that gives me the exact opposite of what I want: all the photos without edits. 🫠
Any tips on the correct syntax here would be much appreciated.
Hello!
In iOS1.7.5, photogrammetry sessions cannot be performed on iPhones without LiDAR, but I don't think there is much difference in GPU performance between those with and without LiDAR. For example, the chips installed in the iPhone 14 Pro and iPhone 15 are the same A16 Bionic, and I think the GPU performance is also the same. Despite this, photogrammetry can be performed on the iPhone 14 Pro but not on the iPhone 15. Why is this?
In fact, we have confirmed that if you transfer images taken with an iPhone 16 without LiDAR to an iPhone 16 Pro and run a photogrammetry session using those images, a 3D model can be generated.
Also, will photogrammetry be able to be performed on high-performance iPhones without LiDAR in the future?
Topic:
Media Technologies
SubTopic:
Photos & Camera