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How to detect when iOS Camera app starts video recording (with Allow Audio Playback ON)?
Since iOS 18, the system setting “Allow Audio Playback” (enabled by default) allows third-party app audio to continue playing while the user is recording video with the Camera app. This has created a problem for the app I’m developing. ➡️ The problem: My app plays continuous audio in both foreground and background states. If the user starts recording video using the iOS Camera app, the app’s audio — still playing in the background — gets captured in the video — obviously an unintended behavior. Yes, the user could stop the app manually before starting the video recording, but that can’t be guaranteed. As a developer, I need a way to stop the app’s audio before the video recording begins. So far, I haven’t found a reliable way to detect when video recording starts if ‘Allow Audio Playback’ is ON. ➡️ What I’ve tried: — AVAudioSession.interruptionNotification → doesn’t fire — devicesChangedEventStream → not triggered I don’t want to request mic permission (app doesn’t use mic). also, disabling the app from playing audio in the background isn’t an option as it is a crucial part of the user experience ➡️ What I need: A reliable, supported way to detect when the Camera app begins video recording, without requiring mic access — so I can stop audio and avoid unintentional overlap with the user’s recordings. Any official guidance, workarounds, or AVFoundation techniques would be greatly appreciated. Thanks.
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Aug ’25
Clean up render files saved to PHContentEditingOutput.renderedContentURL
I discovered when editing photos with the PhotoKit API, PHContentEditingOutput's renderedContentURL is a file in the app container's tmp directory with a filename that seems to follow the format render.<uuid>.JPG, and that file does not get deleted if the edit does not complete successfully (the user cancels the edit request, an error occurs, the app crashes, etc). I understand the system is supposed to automatically delete tmp files every once in a while, but some users are noticing my app's Documents & Data inflates, so I'm considering deleting these render files each time the app is launched. But I don't want to delete everything in the tmp directory as there could possibly be other data in there. What's the best way to remove those temporary files? Does the filename always start with render. no matter the device language? I thought I'd delete files in NSTemporaryDirectory() with that prefix but then I discovered in Mac Catalyst the location is not the tmp directory directly, they're in tmp/TemporaryItems/<bundleid>. Thanks!
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142
Oct ’25
How to Keep Camera Running in iOS PiP Mode (Like WhatsApp/Google Meet)?
I'm using Picture-in-Picture (PiP) mode in my native iOS application, which is similar to Google Meet, using the VideoSDK.live Native iOS SDK. The SDK has built-in support for PiP and it's working fine for the most part. However, I'm running into a problem: When the app enters PiP mode, the local camera (self-video) of the participant freezes or stops. I want to fix this and achieve the same smooth behavior seen in apps like Google Meet and WhatsApp, where the local camera keeps working even in PiP mode. I've been trying to find documentation or examples on how to achieve this but haven't had much luck. I came across a few mentions that using the camera in the background may require special entitlements from Apple (like in the entitlements file). Most of the official documentation says background camera access is restricted due to Apple’s privacy policies. So my questions are: Has anyone here successfully implemented background camera access in PiP mode on iOS? If yes, what permissions or entitlements are required? How do apps like WhatsApp and Google Meet achieve this functionality on iPhones? Any help, advice, or pointers would be really appreciated!
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283
Aug ’25
Option to Set Default Interpolation for Keyframes to “Linear” in Final Cut Pro
In Final Cut Pro, keyframes for transform parameters (such as Position, Scale, and Rotation) are automatically set to “Smooth” interpolation. This often results in undesired easing between keyframes, especially when linear motion is required. Currently, we have to manually adjust each keyframe to "Linear" using the Video Animation Editor, which can be time-consuming when working with many keyframes. Would it be possible to add an option to set the default keyframe interpolation to "Linear"—either globally in Preferences or per parameter in the Inspector? This would greatly streamline the animation workflow for many editors. Thank you for considering this request!
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145
Jun ’25
401 Authorization error for Music Feed API
I've established proper authorization for general music api calls, but when I use that same authorization to retrieve metadata for the latest music feeds (see https://developer.apple.com/documentation/applemusicfeed/requesting-a-feed-export), I get a 401 Unauthorized error. As per the documentation, I'm simply issuing a GET against https://api.media.apple.com/v1/feed/album/latest. Are there different entitlements needed for the Music Feed API?
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May ’25
Error saving image to Camera Roll on iPhone 17 Pro
I'm experiencing an issue with my app when saving images to the camera roll. This is intermittent, but it happens several times a day. The error I receive is the following: Connection to assetsd was interrupted - assetsd exited, died, or closed the photo library Error getting remote object proxy for -[PLNonBindingAssetsdPhotoKitClient sendChangesRequest:reply:]_block_invoke: Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.photos.service" UserInfo={NSDebugDescription=connection to service named com.apple.photos.service} PhotoKit XPC proxy is invalid. Dropping request on the floor and returning an error: Error Domain=PHPhotosErrorDomain Code=3301 "(null)" (underlying error Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.photos.service" UserInfo={NSDebugDescription=connection to service named com.apple.photos.service}) CoreData: error: XPC: synchronousRemoteObjectProxyWithErrorHandler: store 'file:///var/mobile/Media/PhotoData/Photos.sqlite' encountered error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003." UserInfo={NSDebugDescription=The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003.} CoreData: error: XPC: synchronousRemoteObjectProxyWithErrorHandler: store 'file:///var/mobile/Media/PhotoData/Photos.sqlite' encountered error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003." UserInfo={NSDebugDescription=The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003.} My code is unchanged from using my app daily on an iPhone 16 Pro with iOS 26. I never saw the issue on this device. Here is an excerpt from my code for saving the image: var localIdentifier = String() PHPhotoLibrary.shared().performChanges({ let albumChangeRequest = PHAssetCollectionChangeRequest(for: album) let assetCreationRequest = PHAssetCreationRequest.forAsset() let options = PHAssetResourceCreationOptions() assetCreationRequest.addResource(with: .photo, data: imageData, options: options) assetCreationRequest.creationDate = Date.now let placeHolder = assetCreationRequest.placeholderForCreatedAsset albumChangeRequest?.addAssets([placeHolder!] as NSArray) if placeHolder != nil { localIdentifier = (placeHolder?.localIdentifier)! } }) { (didSucceed, error) in OperationQueue.main.addOperation({ didSucceed ? success(localIdentifier) : failure(error) }) } I'm not sure why this would be device specific but I have had users with iPhone 17 Pro and iPhone Air reporting the issue. Alex
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488
Sep ’25
Capture session interrupted randomly
We are facing a strange issue where a small portion of our large userbase can not start the capture session in our app, as it gets interrupted with the following reason: AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps Our users are all from iPhones, no one is using an iPad. Just to be sure we have set session.isMultitaskingCameraAccessEnabled = true but it does not seem to make any difference. Another weird interruption we are seeing
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135
Jun ’25
Invalid album IDs in parquet files
I’m spot-checking some of the data I’m extracting from the Apple Music Feed parquet files and finding numerous issues of invalid album IDs. For example, just looking at any album with a primary artist id of 163043, I see a few albums that are not available at music.apple.com/us/album/NNN. These include: 981094158 - Time and the River 1803443737 - Celebration (Live New York ’80) 1525426873 - Anything You Want: The Warner-Reprise-Elektra Years I notice that neither of these album ids are returned using the general Music API, so I’m a bit confused why they would exist in the parquet files at all. Thanks.
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May ’25
AVAssetResourceLoaderDelegate for radio stream
Hi everyone, I’m trying to use AVAssetResourceLoaderDelegate to handle a live radio stream (e.g. Icecast/HTTP stream). My goal is to have access to the last 30 seconds of audio data during playback, so I can analyze it for specific audio patterns in near-real-time. I’ve implemented a custom resource loader that works fine for podcasts and static files, where the file size and content length are known. However, for infinite live streams, my current implementation stops receiving new loading requests after the first one is served. As a result, the playback either stalls or fails to continue. Has anyone successfully used AVAssetResourceLoaderDelegate with a continuous radio stream? Or maybe you can suggest betterapproach for buffering and analyzing live audio? Any tips, examples, or advice would be appreciated. Thanks!
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Jun ’25
Clarification on SFSpeechRecognizer system alert message and service URLs for whitelisting
Hello Apple Engineers, I am developing a feature related to SpeechRecognizer (import Speech), and I have two questions: After adding the NSSpeechRecognitionUsageDescription key in my Info.plist, when I initialize an SFSpeechRecognizer instance, the system shows an authorization alert. The alert contains a pre-defined message from Apple: “Speech data from this app will be sent to Apple to process your requests. This will also help Apple improve its speech recognition technology.” Is it possible to remove or customize this message? My app runs in a network environment with a whitelist. I need to know which URL the SFSpeechRecognizer instance connects to, and which port it uses, so that I can add it to the whitelist. Thank you very much for your support! Best regards, Yu Cheng
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249
Sep ’25
MusicKit playbackTime Accuracy
Hello, Has anyone else experienced variations in the accuracy of the playbackTime value? After a few seconds of playback, the reported time adjusts by a fraction of a second, making it difficult to calculate the actual playbackTime of the audio. This can be recreated by playing a song in MusicKit, recording the start time of the audio, playing for at least 10-20 seconds, and then comparing the playbackTime value to one calculated using the start time of the audio. In my experience this jump occurs after about 10 seconds of playback. Any help would be appreciated. Thanks!
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May ’25
AVAssetWriterInput Crash on appendSampleBuffer Converting PCM
Overview We are producing audio in real time from an editing application and are trying to put that on an HLS stream. We attempt to submit PCM samples through an audio writer but are getting a crash after a select number of samples have been appended. Depending on the number of audio frames in the PCM buffer, we might get more iterations before the crash but it always has the same traceback (see below). Code The setup is rather simple. We took inspiration from a few sources around the web. NSMutableDictionary *audio = [[NSMutableDictionary alloc] init]; [audio setObject:@(kAudioFormatMPEG4AAC) forKey:AVFormatIDKey]; [audio setObject:[NSNumber numberWithInt:config.audioSampleRate] // 48000 forKey:AVSampleRateKey]; [audio setObject:[NSNumber numberWithInt:config.audioChannels] // 2 forKey:AVNumberOfChannelsKey]; [audio setObject:@160000 forKey:AVEncoderBitRateKey]; m_audioConfig = [[NSDictionary alloc] initWithDictionary:audio]; m_audio = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeAudio outputSettings:m_audioConfig]; AVAudioFrameCount audioFrames = BUFFER_SAMPLES * bCount; AVAudioPCMBuffer *pcmBuffer = [[AVAudioPCMBuffer alloc] initWithPCMFormat:m_full.pcmFormat frameCapacity:audioFrames]; pcmBuffer.frameLength = pcmBuffer.frameCapacity; AudioChannelLayout layout; memset(&layout, 0, sizeof(layout)); layout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo; CMFormatDescriptionRef format; OSStatus stats = CMAudioFormatDescriptionCreate( kCFAllocatorDefault, pcmBuffer.format.streamDescription, sizeof(layout), &layout, 0, nil, nil, &format ); for (int i = 0; i < bCount; i++) { AudioPCM pcm; audioCallback->callback(pcm); memcpy(*(pcmBuffer.int16ChannelData) + (bufferSize * i), pcm.data, bufferSize); } size_t samplesConsumed = BUFFER_SAMPLES * bCount; CMSampleBufferRef sampleBuffer; CMSampleTimingInfo timing; timing.duration = CMTimeMake(1, config.audioSampleRate); timing.presentationTimeStamp = presentationTime; timing.decodeTimeStamp = kCMTimeInvalid; OSStatus ostatus = CMSampleBufferCreate( kCFAllocatorDefault, nil, false, nil, nil, format, (CMItemCount)pcmBuffer.frameLength, 1, &timing, 0, nil, &sampleBuffer ); //// ostatus = CMSampleBufferSetDataBufferFromAudioBufferList( sampleBuffer, kCFAllocatorDefault, kCFAllocatorDefault, kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment, pcmBuffer.audioBufferList ); if (ostatus != noErr) { NSLog(@"fill audio sample from buffer list failed: %s", logAudioError(ostatus)); return; } ostatus = CMSampleBufferSetDataReady(sampleBuffer); if (ostatus != noErr) { NSLog(@"set sample buffer ready failed: %s", logAudioError(ostatus)); return; } // Finally we can attach it, then shove the presentation time forward [m_audio appendSampleBuffer:sampleBuffer]; The Crash The crash points towards some level of deallocation when the conversion tooling is done or has enough samples to process an output packet? It's had to say. 0 caulk 0x1a1e9532c caulk::alloc::tiered_allocator<caulk::alloc::size_range_tier<0ul, 1008ul, caulk::alloc::tree_allocator<caulk::alloc::chunk_allocator<caulk::alloc::page_allocator, caulk::alloc::bitmap_allocator, caulk::alloc::embed_block_memory, 16384ul, 16ul, 6ul>>>, caulk::alloc::size_range_tier<1009ul, 256000ul, caulk::alloc::guarded_edges_allocator<caulk::alloc::consolidating_free_map<caulk::alloc::page_allocator, 10485760ul>, 4ul>>, caulk::alloc::tracking_allocator<caulk::alloc::page_allocator>>::deallocate(caulk::alloc::block, unsigned long) + 636 1 AudioToolboxCore 0x1993fbfe4 ExtendedAudioBufferList_Destroy + 112 2 AudioToolboxCore 0x1993d5fe0 std::__1::__optional_destruct_base<ACCodecOutputBuffer, false>::~__optional_destruct_base[abi:ne180100]() + 68 3 AudioToolboxCore 0x1993d5f48 acv2::CodecConverter::~CodecConverter() + 196 4 AudioToolboxCore 0x1993d5e5c acv2::CodecConverter::~CodecConverter() + 16 5 AudioToolboxCore 0x1992574d8 std::__1::vector<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>, std::__1::allocator<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>>>::__clear[abi:ne180100]() + 84 6 AudioToolboxCore 0x199259acc acv2::AudioConverterChain::RebuildConverterChain(acv2::ChainBuildSettings const&) + 116 7 AudioToolboxCore 0x1992596ec acv2::AudioConverterChain::SetProperty(unsigned int, unsigned int, void const*) + 1808 8 AudioToolboxCore 0x199324acc acv2::AudioConverterV2::setProperty(unsigned int, unsigned int, void const*) + 84 9 AudioToolboxCore 0x199327f08 with_resolved(OpaqueAudioConverter*, caulk::function_ref<int (AudioConverterAPI*)>) + 60 10 AudioToolboxCore 0x1993281e4 AudioConverterSetProperty + 72 11 MediaToolbox 0x1a7566c2c FigSampleBufferProcessorCreateWithAudioCompression + 2296 12 MediaToolbox 0x1a754db08 0x1a70b5000 + 4819720 13 MediaToolbox 0x1a754dab4 FigMediaProcessorCreateForAudioCompressionWithFormatWriter + 100 14 MediaToolbox 0x1a77ebb98 0x1a70b5000 + 7564184 15 MediaToolbox 0x1a7804158 0x1a70b5000 + 7663960 16 MediaToolbox 0x1a7801da0 0x1a70b5000 + 7654816 17 AVFCore 0x1ada530c4 -[AVFigAssetWriterTrack addSampleBuffer:error:] + 192 18 AVFCore 0x1ada55164 -[AVFigAssetWriterAudioTrack _flushPendingSampleBuffersReturningError:] + 500 19 AVFCore 0x1ada55354 -[AVFigAssetWriterAudioTrack addSampleBuffer:error:] + 472 20 AVFCore 0x1ada4ebf0 -[AVAssetWriterInputWritingHelper appendSampleBuffer:error:] + 128 21 AVFCore 0x1ada4c354 -[AVAssetWriterInput appendSampleBuffer:] + 168 22 lib_devapple_hls.dylib 0x115d2c7cc detail::AppleHLSImplementation::audioRuntime() + 1052 23 lib_devapple_hls.dylib 0x115d2d094 void* std::__1::__thread_proxy[abi:ne180100]<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct>>, void (detail::AppleHLSImplementation::*)(), detail::AppleHLSImplementation*>>(void*) + 72 24 libsystem_pthread.dylib 0x196e5b2e4 _pthread_start + 136 Any insight would be welcome!
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Jun ’25
MIDI output form Standalone MIDI Processor Demo App to DAW
I am trying to get MIDI output from the AU Host demo app using the recent MIDI processor example. The processor works correctly in Logic Pro, but I cannot send MIDI from the AUv3 extension in standalone mode using the default host app to another program (e.g., Ableton). The MIDI manager, which is part of the standalone host app, works fine, and I can send MIDI using it directly—Ableton receives it without issues. I have already set the midiOutputNames in the extension, and the midiOutBlock is mapped. However, the MIDI data from the AUv3 extension does not reach Ableton in standalone mode. I suspect the issue is that midiOutBlock might never be called in the plugin, or perhaps an input to the plugin is missing, which prevents it from sending MIDI. I am currently using the default routing. I have modified the MIDI manager such that it works well as described above. Here is a part of my code for SimplePlayEngine.swift and my MIDIManager.swift for reference: @MainActor @Observable public class SimplePlayEngine { private let midiOutBlock: AUMIDIOutputEventBlock = { sampleTime, cable, length, data in return noErr } var scheduleMIDIEventListBlock: AUMIDIEventListBlock? = nil public init() { engine.attach(player) engine.prepare() setupMIDI() } private func setupMIDI() { if !MIDIManager.shared.setupPort(midiProtocol: MIDIProtocolID._2_0, receiveBlock: { [weak self] eventList, _ in if let scheduleMIDIEventListBlock = self?.scheduleMIDIEventListBlock { _ = scheduleMIDIEventListBlock(AUEventSampleTimeImmediate, 0, eventList) } }) { fatalError("Failed to setup Core MIDI") } } func initComponent(type: String, subType: String, manufacturer: String) async -> ViewController? { reset() guard let component = AVAudioUnit.findComponent(type: type, subType: subType, manufacturer: manufacturer) else { fatalError("Failed to find component with type: \(type), subtype: \(subType), manufacturer: \(manufacturer))" ) } do { let audioUnit = try await AVAudioUnit.instantiate( with: component.audioComponentDescription, options: AudioComponentInstantiationOptions.loadOutOfProcess) self.avAudioUnit = audioUnit self.connect(avAudioUnit: audioUnit) return await audioUnit.loadAudioUnitViewController() } catch { return nil } } private func startPlayingInternal() { guard let avAudioUnit = self.avAudioUnit else { return } setSessionActive(true) if avAudioUnit.wantsAudioInput { scheduleEffectLoop() } let hardwareFormat = engine.outputNode.outputFormat(forBus: 0) engine.connect(engine.mainMixerNode, to: engine.outputNode, format: hardwareFormat) do { try engine.start() } catch { isPlaying = false fatalError("Could not start engine. error: \(error).") } if avAudioUnit.wantsAudioInput { player.play() } isPlaying = true } private func resetAudioLoop() { guard let avAudioUnit = self.avAudioUnit else { return } if avAudioUnit.wantsAudioInput { guard let format = file?.processingFormat else { fatalError("No AVAudioFile defined.") } engine.connect(player, to: engine.mainMixerNode, format: format) } } public func connect(avAudioUnit: AVAudioUnit?, completion: @escaping (() -> Void) = {}) { guard let avAudioUnit = self.avAudioUnit else { return } engine.disconnectNodeInput(engine.mainMixerNode) resetAudioLoop() engine.detach(avAudioUnit) func rewiringComplete() { scheduleMIDIEventListBlock = auAudioUnit.scheduleMIDIEventListBlock if isPlaying { player.play() } completion() } let hardwareFormat = engine.outputNode.outputFormat(forBus: 0) engine.connect(engine.mainMixerNode, to: engine.outputNode, format: hardwareFormat) if isPlaying { player.pause() } let auAudioUnit = avAudioUnit.auAudioUnit if !auAudioUnit.midiOutputNames.isEmpty { auAudioUnit.midiOutputEventBlock = midiOutBlock } engine.attach(avAudioUnit) if avAudioUnit.wantsAudioInput { engine.disconnectNodeInput(engine.mainMixerNode) if let format = file?.processingFormat { engine.connect(player, to: avAudioUnit, format: format) engine.connect(avAudioUnit, to: engine.mainMixerNode, format: format) } } else { let stereoFormat = AVAudioFormat(standardFormatWithSampleRate: hardwareFormat.sampleRate, channels: 2) engine.connect(avAudioUnit, to: engine.mainMixerNode, format: stereoFormat) } rewiringComplete() } } and my MIDI Manager @MainActor class MIDIManager: Identifiable, ObservableObject { func setupPort(midiProtocol: MIDIProtocolID, receiveBlock: @escaping @Sendable MIDIReceiveBlock) -> Bool { guard setupClient() else { return false } if MIDIInputPortCreateWithProtocol(client, portName, midiProtocol, &port, receiveBlock) != noErr { return false } for source in self.sources { if MIDIPortConnectSource(port, source, nil) != noErr { print("Failed to connect to source \(source)") return false } } setupVirtualMIDIOutput() return true } private func setupVirtualMIDIOutput() { let virtualStatus = MIDISourceCreate(client, virtualSourceName, &virtualSource) if virtualStatus != noErr { print("❌ Failed to create virtual MIDI source: \(virtualStatus)") } else { print("✅ Created virtual MIDI source: \(virtualSourceName)") } } func sendMIDIData(_ data: [UInt8]) { print("hey") var packetList = MIDIPacketList() withUnsafeMutablePointer(to: &packetList) { ptr in let pkt = MIDIPacketListInit(ptr) _ = MIDIPacketListAdd(ptr, 1024, pkt, 0, data.count, data) if virtualSource != 0 { let status = MIDIReceived(virtualSource, ptr) if status != noErr { print("❌ Failed to send MIDI data: \(status)") } else { print("✅ Sent MIDI data: \(data)") } } } } }
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684
Aug ’25
Telephoto Lens Keeps Switching to Other Lenses on iPhone 16 Pro Max During PPG (Finger on Camera)
Hi, I’m building a PPG-based heart rate feature where the user places their finger over the rear telephoto camera. On iPhone 16 Pro Max, I'm explicitly selecting the telephoto lens like this: videoDevice = AVCaptureDevice.default(.builtInTelephotoCamera, for: .video, position: .back) And trying to lock it: if #available(iOS 15.0, *), device.activePrimaryConstituentDeviceSwitchingBehavior != .unsupported { try? device.lockForConfiguration() device.setPrimaryConstituentDeviceSwitchingBehavior(.locked, restrictedSwitchingBehaviorConditions: []) device.unlockForConfiguration() } I also lock everything else to prevent dynamic changes: try device.lockForConfiguration() device.focusMode = .locked device.exposureMode = .locked device.whiteBalanceMode = .locked device.videoZoomFactor = 1.0 device.automaticallyEnablesLowLightBoostWhenAvailable = false device.automaticallyAdjustsVideoHDREnabled = false device.unlockForConfiguration() Despite this, the camera still switches to another lens, especially under different lighting, even though the user’s finger fully covers the lens. Questions: How can I completely prevent lens switching in this scenario? Would using videoZoomFactor = 3.0 or 5.0 better enforce use of the telephoto lens? Thanks! Gal
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225
Jul ’25
WWDC25 Camera & Photos group lab summary (Part 3 of 3)
(Note: this is part 3 of a 3 part posting. See Part 1 or Part 2) At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for Camera & Photos. WWDC25 Camera & Photos group lab ran for one hour at 6 PM PST on Tuesday June 10th, 2025 Question 24 What’s the best approach for optimizing barcode scanning using AVFoundation or Vision in low-light or angled scenarios Turn on flash in low-light scenarios Lower framerate to improve exposure and reduce noise Wait until the capture is in focus/notify your user that they need to get closer Question 25 Recent iPhone models introduced macro mode which automatically switch between lenses to take into account of the focal distance difference. Is there official API to implement this, or should I implement them myself using LiDAR values. Using builtInTripleCamera and builtInDualWideCamera will automatically switch to macro when available Question 26 Is there a way to quickly create a thumbnail after the user selects an image with PhotosPicker? File provider API Additional questions from the WWDC25 in-person labs that occurred later in the WWDC week Question 1 When should I build my custom photo picker instead of using the system one? Always start with the system picker -> try embeddable customization APIs -> fallback to custom picker for very special needs Question 2 I'm building a new camera app for pros and I want to give my users the most un-processed image possible, and the most control over the capture as possible. How can I do that with AVCapture? If stills, Brief Bayer RAW capture overview, or Pro RAW if you want Apple's processing and dynamic range If video, talk about prores LOG. Custom exposure settings are available throguh the apis maybe global/local tonemapping discussion?
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411
Jul ’25
Couldn't able to hear audio via speaker on ios real device
This is my native module code implementation I'm getting base64 encoded string from server and passing this to my native module of pcm player to play audio App.tsx PcmPlayer.writeChunk(e.data); PcmPlayer.swift import AVFoundation @objc(PcmPlayer) class PcmPlayer: RCTEventEmitter { private var engine: AVAudioEngine? private var playerNode: AVAudioPlayerNode? private var format: AVAudioFormat? private var bufferQueue = [Data]() private var isPlaying = false private var hasEnded = false private var scheduledBufferCount = 0 private let minBufferBytes = 50000 private let pcmQueue = DispatchQueue(label: "pcm.queue") override init() { super.init() } override func supportedEvents() -> [String]! { return ["onStatus", "onMessage"] } @objc(initPlayer:channels:bitsPerSample:) func initPlayer(_ sampleRate: NSNumber, channels: NSNumber, bitsPerSample: NSNumber) { pcmQueue.async { self.stopInternal() let session = AVAudioSession.sharedInstance() do { try session.setCategory(.playback, mode: .default, options: []) try session.setActive(true, options: .notifyOthersOnDeactivation) try session.setMode(.default) print("🔈 Audio session active. Output route:", session.currentRoute.outputs) } catch { print("❌ Audio session setup failed:", error) return } self.engine = AVAudioEngine() self.playerNode = AVAudioPlayerNode() guard let engine = self.engine, let playerNode = self.playerNode else { print("❌ Engine or playerNode is nil") return } engine.attach(playerNode) self.format = AVAudioFormat(commonFormat: .pcmFormatFloat32, sampleRate: sampleRate.doubleValue, channels: AVAudioChannelCount(channels.uintValue), interleaved: false) guard let format = self.format else { print("❌ Failed to create AVAudioFormat") return } engine.connect(playerNode, to: engine.mainMixerNode, format: format) do { try engine.start() playerNode.play() engine.mainMixerNode.outputVolume = 1.0 print("✅ AVAudioEngine started with format:", format) } catch { print("❌ Engine start failed:", error) } self.hasEnded = false } } @objc(writeChunk:) func writeChunk(_ base64Pcm: String) { pcmQueue.async { guard base64Pcm.count >= 10 else { print("⚠️ Skipping short base64 string") return } var padded = base64Pcm let mod4 = base64Pcm.count % 4 if mod4 > 0 { padded += String(repeating: "=", count: 4 - mod4) } guard let data = Data(base64Encoded: padded, options: .ignoreUnknownCharacters) else { print("❌ Failed to decode base64") return } self.bufferQueue.append(data) print("📥 Received PCM chunk (\(data.count) bytes)") print("📥 writeChunk called. isPlaying=\(self.isPlaying), bufferQueue.count=\(self.bufferQueue.count)") if !self.isPlaying { self.isPlaying = true self.waitForBufferAndStartPlayback() } else if self.scheduledBufferCount == 0 { self.isPlaying = true self.waitForBufferAndStartPlayback() } } } private func waitForBufferAndStartPlayback() { DispatchQueue.global().async { while self.queueSize() < self.minBufferBytes && !self.hasEnded { Thread.sleep(forTimeInterval: 0.01) } self.writeLoop() } } private func writeLoop() { DispatchQueue.global().async { writeLoop: while self.isPlaying { if self.bufferQueue.isEmpty { for _ in 0..<100 { Thread.sleep(forTimeInterval: 0.01) if !self.bufferQueue.isEmpty { break } } if self.bufferQueue.isEmpty { print("🔇 No more data to play after waiting") self.isPlaying = false break writeLoop } } var data: Data? self.pcmQueue.sync { if !self.bufferQueue.isEmpty { data = self.bufferQueue.removeFirst() } } guard let chunk = data else { print("⚠️ No data to process") continue } if let buffer = self.pcmBufferFromData(chunk) { self.scheduledBufferCount += 1 self.playerNode?.scheduleBuffer(buffer, completionHandler: { self.pcmQueue.async { self.scheduledBufferCount -= 1 if self.bufferQueue.isEmpty && self.scheduledBufferCount == 0 { print("ℹ️ Playback idle - waiting for more data") self.isPlaying = false } } }) } } } } private func pcmBufferFromData(_ data: Data) -> AVAudioPCMBuffer? { guard let format = self.format else { return nil } let frameCount = UInt32(data.count / 2) guard let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: frameCount) else { print("❌ Failed to create AVAudioPCMBuffer") return nil } buffer.frameLength = frameCount guard let floatChannelData = buffer.floatChannelData?[0] else { print("❌ floatChannelData is nil") return nil } data.withUnsafeBytes { (rawBuffer: UnsafeRawBufferPointer) in let int16Buffer = rawBuffer.bindMemory(to: Int16.self) let count = min(int16Buffer.count, Int(frameCount)) for i in 0..<count { floatChannelData[i] = Float32(int16Buffer[i]) / Float32(Int16.max) } } return buffer } @objc(stopPlayer) func stopPlayer() { pcmQueue.async { self.stopInternal() } } private func stopInternal() { print("🛑 stopInternal called") self.playerNode?.stop() self.engine?.stop() self.engine?.reset() self.playerNode = nil self.engine = nil self.format = nil self.bufferQueue.removeAll() self.isPlaying = false self.hasEnded = true self.scheduledBufferCount = 0 } @objc(canWrite:rejecter:) func canWrite(_ resolve: @escaping RCTPromiseResolveBlock, rejecter reject: RCTPromiseRejectBlock) { pcmQueue.async { resolve(self.bufferQueue.count < 20) } } @objc(flushPlayer:rejecter:) func flushPlayer(_ resolve: @escaping RCTPromiseResolveBlock, rejecter reject: RCTPromiseRejectBlock) { pcmQueue.async { self.bufferQueue.removeAll() resolve(nil) } } @objc static override func requiresMainQueueSetup() -> Bool { return false } private func queueSize() -> Int { return pcmQueue.sync { return self.bufferQueue.reduce(0) { $0 + $1.count } } } } I couldn't able to hear any audio via my real iOS device also it is working fine on emulator.
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Jul ’25
How to detect when iOS Camera app starts video recording (with Allow Audio Playback ON)?
Since iOS 18, the system setting “Allow Audio Playback” (enabled by default) allows third-party app audio to continue playing while the user is recording video with the Camera app. This has created a problem for the app I’m developing. ➡️ The problem: My app plays continuous audio in both foreground and background states. If the user starts recording video using the iOS Camera app, the app’s audio — still playing in the background — gets captured in the video — obviously an unintended behavior. Yes, the user could stop the app manually before starting the video recording, but that can’t be guaranteed. As a developer, I need a way to stop the app’s audio before the video recording begins. So far, I haven’t found a reliable way to detect when video recording starts if ‘Allow Audio Playback’ is ON. ➡️ What I’ve tried: — AVAudioSession.interruptionNotification → doesn’t fire — devicesChangedEventStream → not triggered I don’t want to request mic permission (app doesn’t use mic). also, disabling the app from playing audio in the background isn’t an option as it is a crucial part of the user experience ➡️ What I need: A reliable, supported way to detect when the Camera app begins video recording, without requiring mic access — so I can stop audio and avoid unintentional overlap with the user’s recordings. Any official guidance, workarounds, or AVFoundation techniques would be greatly appreciated. Thanks.
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Clean up render files saved to PHContentEditingOutput.renderedContentURL
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Oct ’25
How to Keep Camera Running in iOS PiP Mode (Like WhatsApp/Google Meet)?
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Option to Set Default Interpolation for Keyframes to “Linear” in Final Cut Pro
In Final Cut Pro, keyframes for transform parameters (such as Position, Scale, and Rotation) are automatically set to “Smooth” interpolation. This often results in undesired easing between keyframes, especially when linear motion is required. Currently, we have to manually adjust each keyframe to "Linear" using the Video Animation Editor, which can be time-consuming when working with many keyframes. Would it be possible to add an option to set the default keyframe interpolation to "Linear"—either globally in Preferences or per parameter in the Inspector? This would greatly streamline the animation workflow for many editors. Thank you for considering this request!
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Jun ’25
401 Authorization error for Music Feed API
I've established proper authorization for general music api calls, but when I use that same authorization to retrieve metadata for the latest music feeds (see https://developer.apple.com/documentation/applemusicfeed/requesting-a-feed-export), I get a 401 Unauthorized error. As per the documentation, I'm simply issuing a GET against https://api.media.apple.com/v1/feed/album/latest. Are there different entitlements needed for the Music Feed API?
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Activity
May ’25
Error saving image to Camera Roll on iPhone 17 Pro
I'm experiencing an issue with my app when saving images to the camera roll. This is intermittent, but it happens several times a day. The error I receive is the following: Connection to assetsd was interrupted - assetsd exited, died, or closed the photo library Error getting remote object proxy for -[PLNonBindingAssetsdPhotoKitClient sendChangesRequest:reply:]_block_invoke: Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.photos.service" UserInfo={NSDebugDescription=connection to service named com.apple.photos.service} PhotoKit XPC proxy is invalid. Dropping request on the floor and returning an error: Error Domain=PHPhotosErrorDomain Code=3301 "(null)" (underlying error Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.photos.service" UserInfo={NSDebugDescription=connection to service named com.apple.photos.service}) CoreData: error: XPC: synchronousRemoteObjectProxyWithErrorHandler: store 'file:///var/mobile/Media/PhotoData/Photos.sqlite' encountered error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003." UserInfo={NSDebugDescription=The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003.} CoreData: error: XPC: synchronousRemoteObjectProxyWithErrorHandler: store 'file:///var/mobile/Media/PhotoData/Photos.sqlite' encountered error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003." UserInfo={NSDebugDescription=The connection to service created from an endpoint was invalidated: failed to check-in, peer may have been unloaded: mach_error=10000003.} My code is unchanged from using my app daily on an iPhone 16 Pro with iOS 26. I never saw the issue on this device. Here is an excerpt from my code for saving the image: var localIdentifier = String() PHPhotoLibrary.shared().performChanges({ let albumChangeRequest = PHAssetCollectionChangeRequest(for: album) let assetCreationRequest = PHAssetCreationRequest.forAsset() let options = PHAssetResourceCreationOptions() assetCreationRequest.addResource(with: .photo, data: imageData, options: options) assetCreationRequest.creationDate = Date.now let placeHolder = assetCreationRequest.placeholderForCreatedAsset albumChangeRequest?.addAssets([placeHolder!] as NSArray) if placeHolder != nil { localIdentifier = (placeHolder?.localIdentifier)! } }) { (didSucceed, error) in OperationQueue.main.addOperation({ didSucceed ? success(localIdentifier) : failure(error) }) } I'm not sure why this would be device specific but I have had users with iPhone 17 Pro and iPhone Air reporting the issue. Alex
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Sep ’25
Capture session interrupted randomly
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Jun ’25
Invalid album IDs in parquet files
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May ’25
AVAssetResourceLoaderDelegate for radio stream
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Jun ’25
Clarification on SFSpeechRecognizer system alert message and service URLs for whitelisting
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Sep ’25
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Jun ’25
MusicKit playbackTime Accuracy
Hello, Has anyone else experienced variations in the accuracy of the playbackTime value? After a few seconds of playback, the reported time adjusts by a fraction of a second, making it difficult to calculate the actual playbackTime of the audio. This can be recreated by playing a song in MusicKit, recording the start time of the audio, playing for at least 10-20 seconds, and then comparing the playbackTime value to one calculated using the start time of the audio. In my experience this jump occurs after about 10 seconds of playback. Any help would be appreciated. Thanks!
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151
Activity
May ’25
AVAssetWriterInput Crash on appendSampleBuffer Converting PCM
Overview We are producing audio in real time from an editing application and are trying to put that on an HLS stream. We attempt to submit PCM samples through an audio writer but are getting a crash after a select number of samples have been appended. Depending on the number of audio frames in the PCM buffer, we might get more iterations before the crash but it always has the same traceback (see below). Code The setup is rather simple. We took inspiration from a few sources around the web. NSMutableDictionary *audio = [[NSMutableDictionary alloc] init]; [audio setObject:@(kAudioFormatMPEG4AAC) forKey:AVFormatIDKey]; [audio setObject:[NSNumber numberWithInt:config.audioSampleRate] // 48000 forKey:AVSampleRateKey]; [audio setObject:[NSNumber numberWithInt:config.audioChannels] // 2 forKey:AVNumberOfChannelsKey]; [audio setObject:@160000 forKey:AVEncoderBitRateKey]; m_audioConfig = [[NSDictionary alloc] initWithDictionary:audio]; m_audio = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeAudio outputSettings:m_audioConfig]; AVAudioFrameCount audioFrames = BUFFER_SAMPLES * bCount; AVAudioPCMBuffer *pcmBuffer = [[AVAudioPCMBuffer alloc] initWithPCMFormat:m_full.pcmFormat frameCapacity:audioFrames]; pcmBuffer.frameLength = pcmBuffer.frameCapacity; AudioChannelLayout layout; memset(&layout, 0, sizeof(layout)); layout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo; CMFormatDescriptionRef format; OSStatus stats = CMAudioFormatDescriptionCreate( kCFAllocatorDefault, pcmBuffer.format.streamDescription, sizeof(layout), &layout, 0, nil, nil, &format ); for (int i = 0; i < bCount; i++) { AudioPCM pcm; audioCallback->callback(pcm); memcpy(*(pcmBuffer.int16ChannelData) + (bufferSize * i), pcm.data, bufferSize); } size_t samplesConsumed = BUFFER_SAMPLES * bCount; CMSampleBufferRef sampleBuffer; CMSampleTimingInfo timing; timing.duration = CMTimeMake(1, config.audioSampleRate); timing.presentationTimeStamp = presentationTime; timing.decodeTimeStamp = kCMTimeInvalid; OSStatus ostatus = CMSampleBufferCreate( kCFAllocatorDefault, nil, false, nil, nil, format, (CMItemCount)pcmBuffer.frameLength, 1, &timing, 0, nil, &sampleBuffer ); //// ostatus = CMSampleBufferSetDataBufferFromAudioBufferList( sampleBuffer, kCFAllocatorDefault, kCFAllocatorDefault, kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment, pcmBuffer.audioBufferList ); if (ostatus != noErr) { NSLog(@"fill audio sample from buffer list failed: %s", logAudioError(ostatus)); return; } ostatus = CMSampleBufferSetDataReady(sampleBuffer); if (ostatus != noErr) { NSLog(@"set sample buffer ready failed: %s", logAudioError(ostatus)); return; } // Finally we can attach it, then shove the presentation time forward [m_audio appendSampleBuffer:sampleBuffer]; The Crash The crash points towards some level of deallocation when the conversion tooling is done or has enough samples to process an output packet? It's had to say. 0 caulk 0x1a1e9532c caulk::alloc::tiered_allocator<caulk::alloc::size_range_tier<0ul, 1008ul, caulk::alloc::tree_allocator<caulk::alloc::chunk_allocator<caulk::alloc::page_allocator, caulk::alloc::bitmap_allocator, caulk::alloc::embed_block_memory, 16384ul, 16ul, 6ul>>>, caulk::alloc::size_range_tier<1009ul, 256000ul, caulk::alloc::guarded_edges_allocator<caulk::alloc::consolidating_free_map<caulk::alloc::page_allocator, 10485760ul>, 4ul>>, caulk::alloc::tracking_allocator<caulk::alloc::page_allocator>>::deallocate(caulk::alloc::block, unsigned long) + 636 1 AudioToolboxCore 0x1993fbfe4 ExtendedAudioBufferList_Destroy + 112 2 AudioToolboxCore 0x1993d5fe0 std::__1::__optional_destruct_base<ACCodecOutputBuffer, false>::~__optional_destruct_base[abi:ne180100]() + 68 3 AudioToolboxCore 0x1993d5f48 acv2::CodecConverter::~CodecConverter() + 196 4 AudioToolboxCore 0x1993d5e5c acv2::CodecConverter::~CodecConverter() + 16 5 AudioToolboxCore 0x1992574d8 std::__1::vector<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>, std::__1::allocator<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>>>::__clear[abi:ne180100]() + 84 6 AudioToolboxCore 0x199259acc acv2::AudioConverterChain::RebuildConverterChain(acv2::ChainBuildSettings const&) + 116 7 AudioToolboxCore 0x1992596ec acv2::AudioConverterChain::SetProperty(unsigned int, unsigned int, void const*) + 1808 8 AudioToolboxCore 0x199324acc acv2::AudioConverterV2::setProperty(unsigned int, unsigned int, void const*) + 84 9 AudioToolboxCore 0x199327f08 with_resolved(OpaqueAudioConverter*, caulk::function_ref<int (AudioConverterAPI*)>) + 60 10 AudioToolboxCore 0x1993281e4 AudioConverterSetProperty + 72 11 MediaToolbox 0x1a7566c2c FigSampleBufferProcessorCreateWithAudioCompression + 2296 12 MediaToolbox 0x1a754db08 0x1a70b5000 + 4819720 13 MediaToolbox 0x1a754dab4 FigMediaProcessorCreateForAudioCompressionWithFormatWriter + 100 14 MediaToolbox 0x1a77ebb98 0x1a70b5000 + 7564184 15 MediaToolbox 0x1a7804158 0x1a70b5000 + 7663960 16 MediaToolbox 0x1a7801da0 0x1a70b5000 + 7654816 17 AVFCore 0x1ada530c4 -[AVFigAssetWriterTrack addSampleBuffer:error:] + 192 18 AVFCore 0x1ada55164 -[AVFigAssetWriterAudioTrack _flushPendingSampleBuffersReturningError:] + 500 19 AVFCore 0x1ada55354 -[AVFigAssetWriterAudioTrack addSampleBuffer:error:] + 472 20 AVFCore 0x1ada4ebf0 -[AVAssetWriterInputWritingHelper appendSampleBuffer:error:] + 128 21 AVFCore 0x1ada4c354 -[AVAssetWriterInput appendSampleBuffer:] + 168 22 lib_devapple_hls.dylib 0x115d2c7cc detail::AppleHLSImplementation::audioRuntime() + 1052 23 lib_devapple_hls.dylib 0x115d2d094 void* std::__1::__thread_proxy[abi:ne180100]<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct>>, void (detail::AppleHLSImplementation::*)(), detail::AppleHLSImplementation*>>(void*) + 72 24 libsystem_pthread.dylib 0x196e5b2e4 _pthread_start + 136 Any insight would be welcome!
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Jun ’25
MIDI output form Standalone MIDI Processor Demo App to DAW
I am trying to get MIDI output from the AU Host demo app using the recent MIDI processor example. The processor works correctly in Logic Pro, but I cannot send MIDI from the AUv3 extension in standalone mode using the default host app to another program (e.g., Ableton). The MIDI manager, which is part of the standalone host app, works fine, and I can send MIDI using it directly—Ableton receives it without issues. I have already set the midiOutputNames in the extension, and the midiOutBlock is mapped. However, the MIDI data from the AUv3 extension does not reach Ableton in standalone mode. I suspect the issue is that midiOutBlock might never be called in the plugin, or perhaps an input to the plugin is missing, which prevents it from sending MIDI. I am currently using the default routing. I have modified the MIDI manager such that it works well as described above. 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Activity
Aug ’25
Forward/Reverse Arrows missing in Music/Get Info
There appears to be no method of going forward or backwards in Get Info in the Music application,
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61
Activity
Jun ’25
How to update of live blogs in Apple News automatically?
I am working to update a live blog in Apple News. As far as I know there is an update endpoint to update a content in Apple News. Is there any feature in Apple News to trigger an event when the original content updated and pull the updated content?
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Activity
Aug ’25
Telephoto Lens Keeps Switching to Other Lenses on iPhone 16 Pro Max During PPG (Finger on Camera)
Hi, I’m building a PPG-based heart rate feature where the user places their finger over the rear telephoto camera. On iPhone 16 Pro Max, I'm explicitly selecting the telephoto lens like this: videoDevice = AVCaptureDevice.default(.builtInTelephotoCamera, for: .video, position: .back) And trying to lock it: if #available(iOS 15.0, *), device.activePrimaryConstituentDeviceSwitchingBehavior != .unsupported { try? device.lockForConfiguration() device.setPrimaryConstituentDeviceSwitchingBehavior(.locked, restrictedSwitchingBehaviorConditions: []) device.unlockForConfiguration() } I also lock everything else to prevent dynamic changes: try device.lockForConfiguration() device.focusMode = .locked device.exposureMode = .locked device.whiteBalanceMode = .locked device.videoZoomFactor = 1.0 device.automaticallyEnablesLowLightBoostWhenAvailable = false device.automaticallyAdjustsVideoHDREnabled = false device.unlockForConfiguration() Despite this, the camera still switches to another lens, especially under different lighting, even though the user’s finger fully covers the lens. Questions: How can I completely prevent lens switching in this scenario? Would using videoZoomFactor = 3.0 or 5.0 better enforce use of the telephoto lens? Thanks! Gal
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225
Activity
Jul ’25
WWDC25 Camera & Photos group lab summary (Part 3 of 3)
(Note: this is part 3 of a 3 part posting. See Part 1 or Part 2) At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for Camera & Photos. WWDC25 Camera & Photos group lab ran for one hour at 6 PM PST on Tuesday June 10th, 2025 Question 24 What’s the best approach for optimizing barcode scanning using AVFoundation or Vision in low-light or angled scenarios Turn on flash in low-light scenarios Lower framerate to improve exposure and reduce noise Wait until the capture is in focus/notify your user that they need to get closer Question 25 Recent iPhone models introduced macro mode which automatically switch between lenses to take into account of the focal distance difference. Is there official API to implement this, or should I implement them myself using LiDAR values. Using builtInTripleCamera and builtInDualWideCamera will automatically switch to macro when available Question 26 Is there a way to quickly create a thumbnail after the user selects an image with PhotosPicker? File provider API Additional questions from the WWDC25 in-person labs that occurred later in the WWDC week Question 1 When should I build my custom photo picker instead of using the system one? Always start with the system picker -> try embeddable customization APIs -> fallback to custom picker for very special needs Question 2 I'm building a new camera app for pros and I want to give my users the most un-processed image possible, and the most control over the capture as possible. How can I do that with AVCapture? If stills, Brief Bayer RAW capture overview, or Pro RAW if you want Apple's processing and dynamic range If video, talk about prores LOG. Custom exposure settings are available throguh the apis maybe global/local tonemapping discussion?
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411
Activity
Jul ’25
Use of MusicKit in mobile app to manipulate audio with EQ
Hello, I want to know if there are any restrictions with MusicKit to be used in a mobile app to be able to manipulate audio with an EQ on tracks coming from Apple Music, without modifying the actual track structure/data of course, just the audio output.
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426
Activity
Sep ’25
Couldn't able to hear audio via speaker on ios real device
This is my native module code implementation I'm getting base64 encoded string from server and passing this to my native module of pcm player to play audio App.tsx PcmPlayer.writeChunk(e.data); PcmPlayer.swift import AVFoundation @objc(PcmPlayer) class PcmPlayer: RCTEventEmitter { private var engine: AVAudioEngine? private var playerNode: AVAudioPlayerNode? private var format: AVAudioFormat? private var bufferQueue = [Data]() private var isPlaying = false private var hasEnded = false private var scheduledBufferCount = 0 private let minBufferBytes = 50000 private let pcmQueue = DispatchQueue(label: "pcm.queue") override init() { super.init() } override func supportedEvents() -> [String]! { return ["onStatus", "onMessage"] } @objc(initPlayer:channels:bitsPerSample:) func initPlayer(_ sampleRate: NSNumber, channels: NSNumber, bitsPerSample: NSNumber) { pcmQueue.async { self.stopInternal() let session = AVAudioSession.sharedInstance() do { try session.setCategory(.playback, mode: .default, options: []) try session.setActive(true, options: .notifyOthersOnDeactivation) try session.setMode(.default) print("🔈 Audio session active. Output route:", session.currentRoute.outputs) } catch { print("❌ Audio session setup failed:", error) return } self.engine = AVAudioEngine() self.playerNode = AVAudioPlayerNode() guard let engine = self.engine, let playerNode = self.playerNode else { print("❌ Engine or playerNode is nil") return } engine.attach(playerNode) self.format = AVAudioFormat(commonFormat: .pcmFormatFloat32, sampleRate: sampleRate.doubleValue, channels: AVAudioChannelCount(channels.uintValue), interleaved: false) guard let format = self.format else { print("❌ Failed to create AVAudioFormat") return } engine.connect(playerNode, to: engine.mainMixerNode, format: format) do { try engine.start() playerNode.play() engine.mainMixerNode.outputVolume = 1.0 print("✅ AVAudioEngine started with format:", format) } catch { print("❌ Engine start failed:", error) } self.hasEnded = false } } @objc(writeChunk:) func writeChunk(_ base64Pcm: String) { pcmQueue.async { guard base64Pcm.count >= 10 else { print("⚠️ Skipping short base64 string") return } var padded = base64Pcm let mod4 = base64Pcm.count % 4 if mod4 > 0 { padded += String(repeating: "=", count: 4 - mod4) } guard let data = Data(base64Encoded: padded, options: .ignoreUnknownCharacters) else { print("❌ Failed to decode base64") return } self.bufferQueue.append(data) print("📥 Received PCM chunk (\(data.count) bytes)") print("📥 writeChunk called. isPlaying=\(self.isPlaying), bufferQueue.count=\(self.bufferQueue.count)") if !self.isPlaying { self.isPlaying = true self.waitForBufferAndStartPlayback() } else if self.scheduledBufferCount == 0 { self.isPlaying = true self.waitForBufferAndStartPlayback() } } } private func waitForBufferAndStartPlayback() { DispatchQueue.global().async { while self.queueSize() < self.minBufferBytes && !self.hasEnded { Thread.sleep(forTimeInterval: 0.01) } self.writeLoop() } } private func writeLoop() { DispatchQueue.global().async { writeLoop: while self.isPlaying { if self.bufferQueue.isEmpty { for _ in 0..<100 { Thread.sleep(forTimeInterval: 0.01) if !self.bufferQueue.isEmpty { break } } if self.bufferQueue.isEmpty { print("🔇 No more data to play after waiting") self.isPlaying = false break writeLoop } } var data: Data? self.pcmQueue.sync { if !self.bufferQueue.isEmpty { data = self.bufferQueue.removeFirst() } } guard let chunk = data else { print("⚠️ No data to process") continue } if let buffer = self.pcmBufferFromData(chunk) { self.scheduledBufferCount += 1 self.playerNode?.scheduleBuffer(buffer, completionHandler: { self.pcmQueue.async { self.scheduledBufferCount -= 1 if self.bufferQueue.isEmpty && self.scheduledBufferCount == 0 { print("ℹ️ Playback idle - waiting for more data") self.isPlaying = false } } }) } } } } private func pcmBufferFromData(_ data: Data) -> AVAudioPCMBuffer? { guard let format = self.format else { return nil } let frameCount = UInt32(data.count / 2) guard let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: frameCount) else { print("❌ Failed to create AVAudioPCMBuffer") return nil } buffer.frameLength = frameCount guard let floatChannelData = buffer.floatChannelData?[0] else { print("❌ floatChannelData is nil") return nil } data.withUnsafeBytes { (rawBuffer: UnsafeRawBufferPointer) in let int16Buffer = rawBuffer.bindMemory(to: Int16.self) let count = min(int16Buffer.count, Int(frameCount)) for i in 0..<count { floatChannelData[i] = Float32(int16Buffer[i]) / Float32(Int16.max) } } return buffer } @objc(stopPlayer) func stopPlayer() { pcmQueue.async { self.stopInternal() } } private func stopInternal() { print("🛑 stopInternal called") self.playerNode?.stop() self.engine?.stop() self.engine?.reset() self.playerNode = nil self.engine = nil self.format = nil self.bufferQueue.removeAll() self.isPlaying = false self.hasEnded = true self.scheduledBufferCount = 0 } @objc(canWrite:rejecter:) func canWrite(_ resolve: @escaping RCTPromiseResolveBlock, rejecter reject: RCTPromiseRejectBlock) { pcmQueue.async { resolve(self.bufferQueue.count < 20) } } @objc(flushPlayer:rejecter:) func flushPlayer(_ resolve: @escaping RCTPromiseResolveBlock, rejecter reject: RCTPromiseRejectBlock) { pcmQueue.async { self.bufferQueue.removeAll() resolve(nil) } } @objc static override func requiresMainQueueSetup() -> Bool { return false } private func queueSize() -> Int { return pcmQueue.sync { return self.bufferQueue.reduce(0) { $0 + $1.count } } } } I couldn't able to hear any audio via my real iOS device also it is working fine on emulator.
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Activity
Jul ’25