When shooting with an iPhone 15 or later, it’s possible to capture HEIC or JPEG images that include gain map information conforming to the ISO 21496-1 standard. However, during image format transcoding, the HEIC codec is able to preserve the ISO 21496-1 gain map. But when converting from HEIC to JPEG, the gain map is transformed into the Apple Gain Map format instead. Is there any solution to this issue?
Photos & Camera
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Hi everyone,
We're encountering an unexpected issue with our iPhone-only camera app:
👉 TimeMark - Photo Proof
https://apps.apple.com/us/app/timemark-photo-proof/id6446071834
Problem Description:
Our app uses a full-screen camera view via AVCaptureSession. In some cases reported by users, the camera fails immediately upon app launch, and we receive this interruption reason:
AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps
According to the Apple documentation https://developer.apple.com/documentation/avfoundation/avcapturesession/interruptionreason/videodevicenotavailablewithmultipleforegroundapps?language=objc , this interruption typically occurs when the app is running in a multi-app layout such as Slide Over, Split View, or Picture in Picture — all of which are iPad-only features.
However, this issue is being reported on iPhones, and our app does not support iPad at all.
Also noted in the documentation:
"Given your present AVCaptureSession configuration, the session may only be run if your app occupies the full screen."
Additional Context:
The issue occurs immediately on app launch, before the user can interact with the camera.
We don’t enable multitaskingCameraAccessEnabled.
We are 100% sure this is happening on iPhone, not iPad.
It’s hard to reproduce; users report it happening sporadically.
Locally, we tried playing Picture-in-Picture videos (e.g., Safari/YouTube) before launching our app, but we could not reproduce the issue.
Questions:
Why is this interruption reason occurring on iPhone, which doesn’t officially support Slide Over or Split View?
Could this be caused by some system-level multitasking or resource contention (e.g., Picture in Picture from FaceTime or Safari)?
Would enabling multitaskingCameraAccessEnabled help prevent this issue on iPhone, even though it's designed for iPad?
Enabling multitaskingCameraAccessEnabled seems to require enabling UIBackgroundModes → voip.
Would adding this background mode cause any App Store review risk or rejection if our app doesn't actually use VoIP functionality?
Any help, insight, or suggestions would be greatly appreciated. Thanks in advance!
AVCaptureSession's startRunning method is thread blocking and seems to be slow. What is this method doing behind the scenes?
For context: I'm working on Simulator Camera support and I have a 'fake' AVCaptureDevice that might be causing this. My hypothesis is that AVCaptureSession tries to connect to the device and waits for a notification to be posted back.
I'd love to find a way to let my fake device message AVCaptureSession that it's connected.
Hello everyone,
I'm working on a feature where I need to capture the highest possible quality photo (e.g., 24MP on supported devices) and upload it to our server. I don't need the photos to appear in user's main Photos app so I thought I could store the photos in app's private directory using FileManager until they are uploaded. This wouldn't require requesting Photo Library permission, maximizing user privacy.
The documentation on AVCapturePhotoOutput states that "the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled"
/**
@property maxPhotoDimensions
@abstract
Indicates the maximum resolution of the requested photo.
@discussion
Set this property to enable requesting of images up to as large as the specified dimensions. Images returned by AVCapturePhotoOutput may be smaller than these dimensions but will never be larger. Once set, images can be requested with any valid maximum photo dimensions by setting AVCapturePhotoSettings.maxPhotoDimensions on a per photo basis. The dimensions set must match one of the dimensions returned by AVCaptureDeviceFormat.supportedMaxPhotoDimensions for the current active format. Changing this property may trigger a lengthy reconfiguration of the capture render pipeline so it is recommended that this is set before calling -[AVCaptureSession startRunning].
Note: When supported, the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled.
*/
@available(iOS 16.0, *)
open var maxPhotoDimensions: CMVideoDimensions
(btw. this note is not present in the docs https://developer.apple.com/documentation/avfoundation/avcapturephotooutput/maxphotodimensions)
Enabling autoDeferredPhotoDeliveryEnabled means that for a 24MP capture, the system will call the photoOutput(_:didFinishCapturingDeferredPhotoProxy:error:) delegate method, providing a proxy object instead of the final image data.
According to the WWDC23 session "Create a more responsive camera experience," this AVCaptureDeferredPhotoProxy must be saved to the PHPhotoLibrary using a PHAssetCreationRequest with the resource type .photoProxy. The system then handles the final processing in the background within the library.
To use deferred photo processing, you'll need to have write permission to the photo library to store the proxy photo, and read permission if your app needs to show the final photo or wants to modify it in any way.
https://developer.apple.com/videos/play/wwdc2023/10105/?time=799
This seems to create a hard dependency on the Photo Library for accessing 24MP images.
My question is:
Is there any way to receive the final, processed 24MP image data directly in the app after a deferred capture, without using PHPhotoLibrary as the processing intermediary?
For example, is there a delegate callback or a mechanism I'm missing that provides the final data for a deferred photo, allowing an app to handle it in-memory or in its own private sandbox, completely bypassing the user's Photo Library?
Our goal is to follow Apple's privacy-first principles by avoiding requesting a PHPhotoLibrary authorization when our app's core function doesn't require access to the user's photo collection.
Thank you for your time and any clarification you can provide.
I am able to capture 48mp photos using .builtInWideAngleCamera, but it seems like .builtInTripleCamera is capped at 12mp?
Is there a way to capture 48mp photos using .builtInTripleCamera? Because .builtInTripleCamera provides smooth transition between cameras during zooming, and I'd like to keep this behavior.
New iPhone 17 Pro have all their cameras at 48mp. Is there a chance that their .builtInTripleCamera is capable of capturing 48mp? Or is this an API limitation?
If the app is launched from LockedCameraCapture and if the settings button is tapped, I need to launch the main app.
CameraViewController:
func settingsButtonTapped() {
#if isLockedCameraCaptureExtension
//App is launched from Lock Screen
//Launch main app here...
#else
//App is launched from Home Screen
self.showSettings(animated: true)
#endif
}
In this document:
https://developer.apple.com/documentation/lockedcameracapture/creating-a-camera-experience-for-the-lock-screen
Apple asks you to use:
func launchApp(with session: LockedCameraCaptureSession, info: String) {
Task {
do {
let activity = NSUserActivityTypeLockedCameraCapture
activity.userInfo = [UserInfoKey: info]
try await session.openApplication(for: activity)
} catch {
StatusManager.displayError("Unable to open app - \(error.localizedDescription)")
}
}
}
However, the documentation states that this should be placed within the extension code - LockedCameraCapture. If I do that, how can I call that all the way down from the main app's CameraViewController?
Hey,
There seems to be an inconsistency when capturing a photo using
QualityPrioritization.Quality on the iPhone 17 Pro Main wide Lens. If you zoom above "2x" the output image always has "-2.0ev" bias in the meta data and looks underexposued. This does not happen at zoom levels above 2, or if you set the QualityPrioritization to .Balanced.
See below:
with .Quality
with .Balanced
This does not happen on the other lenses.
I'm using a simple set up and it is consistent across JPEG and ProRAW capture. I have a demo project if that is useful.
Thanks,
Alex
Support external cameras in your iPadOS app and use Swift to read multiple camera feeds?
thanks
I am using AVMulti so the user captures two images how can I access those images if there is only one url that stores the captured images for the lockScreenCapture extension ? Plus how can I detect if the user opened the app from the extension to be able to navigate the user to the right screen ?
This is an issue with the Insta360 Flow Pro 2.
My iOS app uses DockKit to control the gimbal; in particular, my app disables tracking and sends angular velocity commands to control the gimbal's orientation. I only try to modify the yaw (rotation around the vertical axis); never the pitch or yaw. Note that I don't send the gimbal to a particular orientation directly; I modify the velocity.
Everything works great for a long period of time: typically for a continuous run of 4-6 hours; in the most recent case, I managed about 36 hours of continous operation before the following problem occurred.
I came back to check on the system, and because no visual activity had occurred in the camera's field of view for a while, the phone had commanded the gimbal to rotate back to a yaw angle of 0 degrees.
So the phone in the gimbal should have been looking straight ahead (i.e. the 0 degree yaw position), but it was definitely looking off at an angle. I've seen this twice now. The first time, when it should have been looking straight ahead, it was in fact looking 60 degrees off center. This time (caught on video, see below), it was off by 22 degrees from center.
Here's the weird part: the gimbal reports this way off center positioning as zero degrees (well close enough to zero, like 0.2 or something that's fine). But, mechanically, the gimbal still knows where zero degrees is: if we double click on the trigger of the Flow Pro 2, which is supposed to reset the gimbal to 0 degrees yaw and pitch, the gimbal responds correctly and reorients to a 0 degree position. However, the yaw values it reports are not zero, but as shown in my video, 22 degrees off axis or so.
Power cycling the gimbal and restarting immediately fixes the problem. Also, I switched from my app to the Insta360 app, which caused the phone to flip from landscape to portrait, then when I returned to my app and switched back to landscape, the gimbal now started reporting correct yaw angles.
Is there a possibility this is a bug in the DockKit framework? Has anyone seen this? I have a case open with Insta360, but although it's clearly a software issue, it's not clear if it's in Insta360's code or the DockKit layer. Any ideas for how I can get out of this mode? My concern is that the phone is in a tripod about 10' off the floor, and not very accessible. Also, if all goes well, we may have about 50 of these systems running, and having to fix them one by one after a few hours is not good.
For a demonstration of this bug, see the following video:
https://octoparry.com/offset.MOV
Any help greatly appreciated.
In the AVP project, a selector pops up, only wanting to filter spatial videos. When selecting the material of one of the spatial videos, the selection result returns empty. How can we obtain the video selected by the user and get the path and the URL of the file
The code is as follows:
PhotosPicker(selection: $selectedItem, matching: .videos) {
Text("Choose a spatial photo or video")
}
func loadTransferable(from imageSelection: PhotosPickerItem) -> Progress {
return imageSelection.loadTransferable(type: URL.self) { result in
DispatchQueue.main.async {
// guard imageSelection == self.imageSelection else { return }
print("加载成功的图片集合:(result)")
switch result {
case .success(let url?):
self.selectSpatialVideoURL = url
print("获取视频链接:(url)")
case .success(nil):
break
// Handle the success case with an empty value.
case .failure(let error):
print("spatial错误:(error)")
// Handle the failure case with the provided error.
}
}
}
}
Can i use iokit usb lib to disable build-in camera?
Hello,
Does anyone have a recipe on how to raycast VNFaceLandmarkRegion2D points obtained from a frame's capturedImage?
More specifically, how to construct the "from" parameter of the frame's raycastQuery from a VNFaceLandmarkRegion2D point?
Do the points need to be flipped vertically? Is there any other transformation that needs to be performed on the points prior to passing them to raycastQuery?
I have an app that edits photos in your library. When I call
try CIContext().writeHEIFRepresentation(of: editedImage, to: fileURL, format: .RGBA8, colorSpace: originalImage.colorSpace!)
The following is logged to the console:
writeImageAtIndex:1012: ⭕️ ERROR: 'App' is trying to save an opaque image (5712x4284) with 'AlphaLast'. This would unnecessarily increase the file size and will double (!!!) the required memory when decoding the image --> ignoring alpha.
What does that mean and how can I resolve it?
Xcode Version 16.0 (16A242d)
iOS 18.1 (22B82)
I set both the AVCapturePhotoOutput and the AVCapturePhotoSettings with maxPhotoDimensions = .init(width: 8064, height: 6048), but still get the 12mp photo.
Topic:
Media Technologies
SubTopic:
Photos & Camera
I have a complex CoreImage pipeline which I'm keen to optimise. I'm aware that calling back to the CPU can have a significant impact on the performance - what is the best way to find out where this is happening?
Hey everyone😊, I am building an app that includes a live camera feed preview. That's all I need to do along side identifying the images with createML's image classification. I don't need to capture images at all. I've seen some very complicated tutorials. I just want to use a couple of lines of code.
Topic:
Media Technologies
SubTopic:
Photos & Camera
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
Hello everyone,
I am looking for a solution to programmatically, e.g. using AppleScript to import photos into the Photos library on MacOS and also push them to the shared library, like it can be done using the standard GUI of the Photos application.
Maybe it is not possible using AppleScript, but using a short Swift script and PhotoKit, I do not not know.
Any help is appreciated!
Thomas
I am seeing a crash on iOS 18.0 in my app due to PHImageManager.default().requestImage. Same crash is seen even while using requestImageDataAndOrientation.
Not sure why this is happening only on iOS 18.0.
Any help on this would be appreciated.
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000010
Exception Codes: 0x0000000000000001, 0x0000000000000010
VM Region Info: 0x10 is not in any region. Bytes before following region: 4310777840
REGION TYPE START - END [ VSIZE] PRT/MAX SHRMOD REGION DETAIL
UNUSED SPACE AT START
--->
Termination Reason: SIGNAL 11 Segmentation fault: 11
Terminating Process: exc handler [695]
Triggered by Thread: 14
Thread 14 name: Dispatch queue: */file=33) .Generic
Thread 14 Crashed:
0 libobjc.A.dylib 0x1944d7020 objc_msgSend + 32
1 PhotoLibraryServices 0x1b080262c +[PLUniformTypeIdentifier utiWithCompactRepresentation:conformanceHint:] + 40
2 Photos 0x1b0081354 _resourceInfoFromResultDict + 1048
3 Photos 0x1b0080a7c fetchResourcesForChoosing + 584
4 Photos 0x1b0080714 ___fetchNonHintResources_block_invoke.227 + 152
5 PhotoLibraryServices 0x1b026b3c4 __53-[PLManagedObjectContext _directPerformBlockAndWait:]_block_invoke + 48
6 CoreData 0x19f171b00 developerSubmittedBlockToNSManagedObjectContextPerform + 228
7 libdispatch.dylib 0x19eeff584 _dispatch_client_callout + 16
8 libdispatch.dylib 0x19eef5728 _dispatch_lane_barrier_sync_invoke_and_complete + 56
9 CoreData 0x19f1c2a0c -[NSManagedObjectContext performBlockAndWait:] + 308
10 PhotoLibraryServices 0x1b026cea4 -[PLManagedObjectContext _directPerformBlockAndWait:] + 144
11 PhotoLibraryServices 0x1b026cdf8 -[PLManagedObjectContext performBlockAndWait:] + 196
12 Photos 0x1b00804a4 _fetchNonHintResources + 292
13 Photos 0x1afeedb38 PHChooserListContinueEnumerating + 144
14 Photos 0x1afeed9f8 -[PHImageResourceChooser presentNextQualifyingResource] + 412
15 Photos 0x1afeed1d0 -[PHImageRequest startRequest] + 2424
16 libdispatch.dylib 0x19eee5aac _dispatch_call_block_and_release + 32
17 libdispatch.dylib 0x19eeff584 _dispatch_client_callout + 16
18 libdispatch.dylib 0x19eeee2d0 _dispatch_lane_serial_drain + 740
19 libdispatch.dylib 0x19eeeede0 _dispatch_lane_invoke + 440
20 libdispatch.dylib 0x19eef91dc _dispatch_root_queue_drain_deferred_wlh + 292
21 libdispatch.dylib 0x19eef8a60 _dispatch_workloop_worker_thread + 540
22 libsystem_pthread.dylib 0x2214d5660 _pthread_wqthread + 292
23 libsystem_pthread.dylib 0x2214d29f8 start_wqthread + 8