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
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
Hello everyone,
I’m working on an iOS app that fetches videos from the "Recently Deleted" album using the Photos framework in Swift. However, I’m unable to fetch any videos, even though the "Recently Deleted" album contains 233 items (including videos), as seen in the Photos app.
Environment:
iOS Version: 18.3.1
Xcode Version: 16.2
Swift Version: Swift 5
Device: iPhone (simulator and physical device both tested)
Photo Library Permission: "All Photos" access granted
Recently Deleted Lock: Face ID/Passcode is disabled for "Recently Deleted"
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
Some users reported that their images are not loading correctly in our app. After a lot of debugging we identified the following:
This only happens when the app is build for Mac Catalyst. Not on iOS, iPadOS, or “real” macOS (AppKit).
The images in question have unusual color spaces. We observed the issue for uRGB and eciRGB v2.
Those images are rendered correctly in Photos and Preview on all platforms.
When displaying the image inside of a UIImageView or in a SwiftUI Image, they render correctly.
The issue only occurs when loading the image via Core Image.
When comparing the different Core Image render graphs between AppKit (working) and Catalyst (faulty) builds, they look identical—except for the result.
Mac (AppKit):
Catalyst:
Something seems to be off when Core Image tries to load an image with foreign color space in Catalyst.
We identified a workaround: By using a CGImageDestination to transcode the image using the kCGImageDestinationOptimizeColorForSharing option, Image I/O will convert the image to sRGB (or similar) and Core Image is able to load the image correctly. However, one potentially loses fidelity this way.
Or might there be a better workaround?
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Image I/O
Photos and Imaging
Core Image
Core Graphics
Has Objective-C been deprecated?
Hi guys,
Can I use CMIO to achieve the following feature on macOS when a USB device (Camera/Mic/Speaker) is connected:
When a third-party video conferencing app is not in a meeting, ensure the app defaults to using the USB device (Camera/Mic/Speaker).
When a third-party conferencing app is in a meeting, ensure the app automatically switches to the USB device (Camera/Mic/Speaker).
Does the library exists in xCode 16.4?
"import WorldCaptureKit" gives error "No such module 'WorldCaptureKit'".
And I do not find any information about the library in the apple documentation.
But AI keeps suggesting me to use the library
Topic:
Media Technologies
SubTopic:
Photos & Camera
Hi! I am making an app for Apple Vision pro (VisionOS 2.5) that is scanning the surroundings and recognises all the texts around you. I tried to use the AVCaptureSession library, but when I run the app from xcode on the real AVP device, the camera is not accessible. I enabled the camera access in my Info.plist: NSCameraUsageDescription Used for live text recognition and I checked camera settings in the AVP, there are no restrictions. However I have always a black square with a crossed camera icon displayed instead of the image from the camera.
I tried a couple of different apps from Github using the AVCaptureSession and they all display the black square instead of the picture.
What can be wrong with the camera?
Topic:
Media Technologies
SubTopic:
Photos & Camera
I developed a driverkit extension based on overriding-the-default-usb-video-class-extension, but the link didn’t give the details of realization. I asked DTS who gave two tips:
1, Do you also have a CMIO extension to load in place of the default overriding-the-default-usb-video-class-extension
2, Your DriverKit extension’s info.plist is also missing the CameraAssistantBundleID.
I want to know why a driverkit extension needs a CMIO extension, what’s the data and control flow?
Issue: After iOS 18.5 release, our app is experiencing a significant increase in AVCaptureSessionInterruptionReason.videoDeviceNotAvailableWithMultipleForegroundApps errors.
Details:
Our camera-related code has not been updated recently.However, we've observed that the error rate has significantly increased starting from May 2025. The error rate has risen from approximately 0.02% (2 in 10,000 users) to 0.1% (1 in 1,000 users). This represents a 5x increase in error occurrence.
The frequency has increased noticeably since iOS 18.5
This is affecting our app's camera functionality and user experience
Questions:
Are there any known changes in iOS 18.5 regarding camera access management?
What are the recommended best practices to handle this interruption reason?
Are there any API changes we should be aware of?
Best,
Shay
AVCaptureVideoDataOutput.preparesCellularRadioForNetworkConnection requires com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning. But I cannot acquire its entitlement. I can't find its entitlement on 'Certificates, Identifiers & Profiles'. Any solutions?
Provisioning profile "iOS Team Provisioning Profile: ......" doesn't include the com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning entitlement.
I'm developing a photo backup app.
To detect newly added or edited photos since the app launched, I keep a local dictionary in the format [localIdentifier: modification_date].
However, PHAsset.modificationDate is not reliable.
It often changes unexpectedly, possibly due to system operations like iCloud metadata updates.
Is there a more reliable way to detect whether a photo has been modified by user since the last app launch?
I'm thinking about using content hash instead, but I'm not sure how heavy this operation is in terms of performance.
Hi all,
I'm working on a custom Metal-based video pipeline using AVCaptureVideoDataOutput, and I've run into an unexpected issue related to exposure.
Setup:
I'm capturing video frames using kCVPixelFormatType_420YpCbCr8BiPlanarFullRange.
In my Metal shader, I:
Convert YCbCr (full range Rec.709) to linear Rec.709 RGB.
Apply Rec.709 → sRGB gamma encoding.
Output to .bgra8Unorm_srgb via MTKView.
Everything renders correctly in terms of colorspace math, but the image appears significantly brighter (~+3 stops EV) compared to AVCaptureVideoPreviewLayer and the native iOS Camera app under the same camera exposure settings.
What I’ve verified:
The color transforms are correct: YCbCr709 to RGB, then linear to sRGB.
I'm not applying any tone mapping or aggressive look LUTs yet.
Camera exposure is locked using:
device.setExposureModeCustom(duration: ..., iso: ...)
The same EV (e.g., ISO 50, 1/125s, f/5.6) on my iPhone appears visually 3 stops brighter than on my digital cameras (Sony/Canon etc).
To match the look of the preview layer or camera app, I have to simulate a ~–3 EV shift in my custom pipeline.
Questions:
Is AVCaptureVideoPreviewLayer applying extra tone mapping, digital gain, or contrast shaping (like OOTF etc)?
Does the camera ISP expose "hotter" (i.e., with more light) internally for the preview layer than what we get in video frame buffers?
Is there a standard way to compensate for this ISP behavior in custom pipelines using AVCaptureVideoDataOutput?
Can this be accounted for using metadata (e.g., exposure bias, gain, gamma curve)?
Topic:
Media Technologies
SubTopic:
Photos & Camera
In iOS 26 (Developer Beta), the AVCaptureMetadataOutputObjectsDelegate no longer receives callbacks when metadataOutput.metadataObjectTypes = [.face] is set. On earlier iOS versions the issue does not occur. Interestingly, face detection works if I set the sessionPreset to .medium, but not with .high — except on the iPhone 16 Pro Max, where it works regardless.
I'm working on a photo app and I want to allow the user to display, edit and delete photos. I can fetch all photos using PHAsset.fetchAssets(with: options). This works as intended.
However, I can't seem to find a way to prevent the user from seeing photos from a Shared Library. The PHAssetSourceType only contains typeCloudShared to only show items from a specific album; not library.
How can I filter by iCloud Shared Library?
Hi everyone,
I’m running into an issue with PHPickerFilter when using PHPickerViewController.
When I configure the picker with a .videos and .livePhotos filter, it seems to work correctly in the Photos tab. However, when I switch to the Collections tab, the filter doesn’t always apply — users can still see and select static image assets in certain collections (e.g. from one of the People & Pets sections).
Here’s a simplified snippet of my setup:
var configuration = PHPickerConfiguration(photoLibrary: .shared())
configuration.selectionLimit = 1
var filters = [PHPickerFilter]()
filters.append(.videos)
filters.append(.livePhotos)
configuration.filter = PHPickerFilter.any(of: filters)
configuration.preferredAssetRepresentationMode = .current
let picker = PHPickerViewController(configuration: configuration)
picker.delegate = self
present(picker, animated: true)
Expected behavior:
The picker should consistently respect the filter across both Photos and Collections tabs, only showing assets that match the filter.
Actual behavior:
The filter seems to apply correctly in the Photos tab, but in the Collections tab, other asset types are still visible/selectable.
Has anyone else encountered this behavior? Is this expected or a known issue, or am I missing something in the configuration?
Thanks in advance!
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Files and Storage
Media Library
Photos and Imaging
PhotoKit
I'm writing a program to control a PTZ camera connected via USB.
I can get access to target camera's unique_id, and also other infos provided by AVFoundation. But I don't know how to locate my target USB device to send a UVC ControlRequest.
There's many Cameras with same VendorID and ProductID connected at a time, so I need a more exact way to find out which device is my target.
It looks that the unique_id provided is (locationID<<32|VendorID<<16|ProductID) as hex string, but I'm not sure if I can always assume this behavior won't change.
Is there's a document declares how AVFoundation generate the unique_id for USB camera, so I can assume this convert will always work? Or is there's a way to send a PTZ control request to AVCaptureDevice?
https://stackoverflow.com/questions/40006908/usb-interface-of-an-avcapturedevice
I have seen this similar question. But I'm worrying that Exacting LocationID+VendorID+ProductID from unique_id seems like programming to implementation instead of interface. So, if there's any other better way to control my camera?
here's my example code for getting unique_id:
//
// camera_unique_id_test.mm
//
// 测试代码:使用C++获取当前系统摄像头的AVCaptureDevice unique_id
//
// 编译命令:
// clang++ -framework AVFoundation -framework CoreMedia -framework Foundation
// camera_unique_id_test.mm -o camera_unique_id_test
//
#include <iostream>
#include <string>
#include <vector>
#import <AVFoundation/AVFoundation.h>
#import <Foundation/Foundation.h>
struct CameraInfo {
std::string uniqueId;
};
std::vector<CameraInfo> getAllCameraDevices() {
std::vector<CameraInfo> cameras;
@autoreleasepool {
NSArray<AVCaptureDevice*>* devices =
[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
AVCaptureDevice* defaultDevice =
[AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
// 遍历所有设备
for (AVCaptureDevice* device in devices) {
CameraInfo info;
// 获取unique_id
info.uniqueId = std::string([device.uniqueID UTF8String]);
cameras.push_back(info);
}
}
return cameras;
}
int main(int argc, char* argv[]) {
std::vector<CameraInfo> cameras = getAllCameraDevices();
for (size_t i = 0; i < cameras.size(); i++) {
const CameraInfo& camera = cameras[i];
std::cout << " 设备 " << (i + 1) << ":" << std::endl;
std::cout << " unique_id: " << camera.uniqueId << std::endl;
}
return 0;
}
and here's my code for UVC control:
// clang++ -framework Foundation -framework IOKit uvc_test.cpp -o uvc_test
#include <iostream>
#include <CoreFoundation/CoreFoundation.h>
#include <IOKit/IOCFPlugIn.h>
#include <IOKit/IOKitLib.h>
#include <IOKit/IOMessage.h>
#include <IOKit/usb/IOUSBLib.h>
#include <IOKit/usb/USB.h>
CFStringRef CreateCFStringFromIORegistryKey(io_service_t ioService,
const char* key) {
CFStringRef keyString = CFStringCreateWithCString(kCFAllocatorDefault, key,
kCFStringEncodingUTF8);
if (!keyString)
return nullptr;
CFStringRef result = static_cast<CFStringRef>(
IORegistryEntryCreateCFProperty(ioService, keyString, kCFAllocatorDefault,
kIORegistryIterateRecursively));
CFRelease(keyString);
return result;
}
std::string GetStringFromIORegistry(io_service_t ioService, const char* key) {
CFStringRef cfString = CreateCFStringFromIORegistryKey(ioService, key);
if (!cfString)
return "";
char buffer[256];
Boolean success = CFStringGetCString(cfString, buffer, sizeof(buffer),
kCFStringEncodingUTF8);
CFRelease(cfString);
return success ? std::string(buffer) : std::string("");
}
uint32_t GetUInt32FromIORegistry(io_service_t ioService, const char* key) {
CFStringRef keyString = CFStringCreateWithCString(kCFAllocatorDefault, key,
kCFStringEncodingUTF8);
if (!keyString)
return 0;
CFNumberRef number = static_cast<CFNumberRef>(
IORegistryEntryCreateCFProperty(ioService, keyString, kCFAllocatorDefault,
kIORegistryIterateRecursively));
CFRelease(keyString);
if (!number)
return 0;
uint32_t value = 0;
CFNumberGetValue(number, kCFNumberSInt32Type, &value);
CFRelease(number);
return value;
}
int main() {
// Get matching dictionary for USB devices
CFMutableDictionaryRef matchingDict =
IOServiceMatching(kIOUSBDeviceClassName);
// Get iterator for matching services
io_iterator_t serviceIterator;
IOServiceGetMatchingServices(kIOMasterPortDefault, matchingDict,
&serviceIterator);
// Iterate through matching devices
io_service_t usbService;
while ((usbService = IOIteratorNext(serviceIterator))) {
uint32_t locationId = GetUInt32FromIORegistry(usbService, "locationID");
uint32_t vendorId = GetUInt32FromIORegistry(usbService, "idVendor");
uint32_t productId = GetUInt32FromIORegistry(usbService, "idProduct");
IOCFPlugInInterface** plugInInterface = nullptr;
IOUSBDeviceInterface** deviceInterface = nullptr;
SInt32 score;
// Get device plugin interface
IOCreatePlugInInterfaceForService(usbService, kIOUSBDeviceUserClientTypeID,
kIOCFPlugInInterfaceID, &plugInInterface,
&score);
// Get device interface
(*plugInInterface)
->QueryInterface(plugInInterface,
CFUUIDGetUUIDBytes(kIOUSBDeviceInterfaceID),
(LPVOID*)&deviceInterface);
(*plugInInterface)->Release(plugInInterface);
// Try to find UVC control interface using CreateInterfaceIterator
io_iterator_t interfaceIterator;
IOUSBFindInterfaceRequest interfaceRequest;
interfaceRequest.bInterfaceClass = kUSBVideoInterfaceClass; // 14
interfaceRequest.bInterfaceSubClass = kUSBVideoControlSubClass; // 1
interfaceRequest.bInterfaceProtocol = kIOUSBFindInterfaceDontCare;
interfaceRequest.bAlternateSetting = kIOUSBFindInterfaceDontCare;
(*deviceInterface)
->CreateInterfaceIterator(deviceInterface, &interfaceRequest,
&interfaceIterator);
(*deviceInterface)->Release(deviceInterface);
io_service_t usbInterface = IOIteratorNext(interfaceIterator);
IOObjectRelease(interfaceIterator);
if (usbInterface) {
std::cout << "Get UVC device with:" << std::endl;
std::cout << "locationId: " << std::hex << locationId << std::endl;
std::cout << "vendorId: " << std::hex << vendorId << std::endl;
std::cout << "productId: " << std::hex << productId << std::endl
<< std::endl;
IOObjectRelease(usbInterface);
}
IOObjectRelease(usbService);
}
IOObjectRelease(serviceIterator);
}
Hi,
I'm a fan of the gallery in vision pro which has video as well as still photography but I'm wondering if Apple has considered adding the projected media tags to heic so that we can go that next step from Spatial photos to Immersive photos. I have a device that can give me 12k x 6k fisheye images in HDR, but it can't do it at a framerate or resolution that's good enough for video, so I want to cut my losses and show off immersive photos instead. Is there something Apple is already working on for APMP stills or should I create my own app that reads metadata inside a HEIC that I infer in a similar way to the demo "ProjectedMediaConversion" is doing for Video. It would be great to have 180VR photos, which could show as Spatial in a gallery view, but going immersive would half-surround you instead of floating in the blurred view. I think that would be a pretty amazing effect.
Topic:
Media Technologies
SubTopic:
Photos & Camera