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The behavior of AVPlayerItem.didPlayToEndTimeNotification is not as expected in iOS 26.
Hello, Environment macOS 15.6.1 / Xcode 26 beta 7 / iOS 26 Beta 9 In a simple AVFoundation video-playback sample, I’m seeing different behavior between iOS 18 and iOS 26 regarding AVPlayerItem.didPlayToEndTimeNotification. I’ve attached a minimal sample below. Please replace videoURL with a valid short video URL. Repro steps Tap “Play” to start playback and let the video finish. The AVPlayerItem.didPlayToEndTimeNotification registered with NotificationCenter should fire, and you should see Play finished. in the console. Without relaunching, tap “Play” again. This is where the issue arises. Observed behavior On iOS 18 and earlier: The video does not play again (it does not restart from the beginning), but AVPlayerItem.didPlayToEndTimeNotification is posted and Play finished. appears in the console. The same happens every time you press “Play”. On iOS 26: Pressing “Play” does not post AVPlayerItem.didPlayToEndTimeNotification. The code path that prints Play finished. is never called (the callback enclosing that line is not invoked again). Building the same program with Xcode 16.4 and running it on an iOS 26 beta device shows the same phenomenon, which suggests there has been a behavioral change for AVPlayerItem.didPlayToEndTimeNotification on iOS 26. I couldn’t find any mention of this in the release notes or API Reference. Because the semantics around AVPlayerItem.didPlayToEndTimeNotification appear to differ, we’re forced to adjust our logic. If there is a way to achieve the iOS 18–style behavior on iOS 26, I would appreciate guidance. Alternatively, if this change is intentional, could you share the reasoning? Is iOS 26 the correct behavior from Apple’s perspective and iOS 18 (and earlier) behavior considered incorrect? Any official clarification would be extremely helpful. import UIKit import AVFoundation final class ViewController: UIViewController { private let videoURL = URL(string: "https://......mp4")! private var player: AVPlayer? private var playerItem: AVPlayerItem? private var playerLayer: AVPlayerLayer? private var observeForComplete: NSObjectProtocol? // UI private let playerContainerView = UIView() private let playButton = UIButton(type: .system) private let stopButton = UIButton(type: .system) private let replayButton = UIButton(type: .system) deinit { if let observeForComplete { NotificationCenter.default.removeObserver(observeForComplete) } } override func viewDidLoad() { super.viewDidLoad() view.backgroundColor = .systemBackground setupUI() setupPlayer() } override func viewDidLayoutSubviews() { super.viewDidLayoutSubviews() playerLayer?.frame = playerContainerView.bounds } // MARK: - Setup private func setupUI() { playerContainerView.translatesAutoresizingMaskIntoConstraints = false playerContainerView.backgroundColor = .black view.addSubview(playerContainerView) // Buttons playButton.setTitle("Play", for: .normal) stopButton.setTitle("Pause", for: .normal) replayButton.setTitle("RePlay", for: .normal) [playButton, stopButton, replayButton].forEach { $0.titleLabel?.font = .systemFont(ofSize: 16, weight: .semibold) $0.translatesAutoresizingMaskIntoConstraints = false $0.contentEdgeInsets = UIEdgeInsets(top: 10, left: 16, bottom: 10, right: 16) } let stack = UIStackView(arrangedSubviews: [playButton, stopButton, replayButton]) stack.axis = .horizontal stack.spacing = 16 stack.alignment = .center stack.distribution = .equalCentering stack.translatesAutoresizingMaskIntoConstraints = false view.addSubview(stack) NSLayoutConstraint.activate([ playerContainerView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 20), playerContainerView.leadingAnchor.constraint(equalTo: view.leadingAnchor), playerContainerView.trailingAnchor.constraint(equalTo: view.trailingAnchor), playerContainerView.heightAnchor.constraint(equalToConstant: 200), stack.topAnchor.constraint(equalTo: playerContainerView.bottomAnchor, constant: 20), stack.centerXAnchor.constraint(equalTo: view.centerXAnchor) ]) // Action playButton.addTarget(self, action: #selector(didTapPlay), for: .touchUpInside) stopButton.addTarget(self, action: #selector(didTapStop), for: .touchUpInside) replayButton.addTarget(self, action: #selector(didTapReplayFromStart), for: .touchUpInside) } private func setupPlayer() { // AVURLAsset -> AVPlayerItem → AVPlayer let asset = AVURLAsset(url: videoURL) let item = AVPlayerItem(asset: asset) self.playerItem = item let player = AVPlayer(playerItem: item) player.automaticallyWaitsToMinimizeStalling = true self.player = player let layer = AVPlayerLayer(player: player) layer.videoGravity = .resizeAspect playerContainerView.layer.addSublayer(layer) layer.frame = playerContainerView.bounds self.playerLayer = layer // Notification if let observeForComplete { NotificationCenter.default.removeObserver(observeForComplete) } if let playerItem { observeForComplete = NotificationCenter.default.addObserver( forName: AVPlayerItem.didPlayToEndTimeNotification, object: playerItem, queue: .main ) { [weak self] _ in guard self != nil else { return } Task { @MainActor in print("Play finished.") } } } } // MARK: - Actions @objc private func didTapPlay() { player?.play() } @objc private func didTapStop() { player?.pause() } // RePlay @objc private func didTapReplayFromStart() { player?.seek(to: .zero, toleranceBefore: .zero, toleranceAfter: .zero) { [weak self] _ in self?.player?.play() } } } I would greatly appreciate an official response from Apple engineering on whether this is an intentional change, a regression, or an API contract clarification, and what the recommended approach is going forward. Thank you.
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Mac OS Tahoe 26.0 (25A354) Sound Glitches When opening the simulator app
Hey there, I just upgraded to Mac OS Tahoe ,son an apple MacBook Pro 2019 16inch. am using IntellijIDEA and Flutter to develop a mobile app which I test on the simulator app running iOS 18.4 . the issue: when I start the simulator app. ( while in the loading phase and in the operation phase as well ), the audio from an already open YouTube tab on safari (this happens on chrome browser as well). the sound glitches and becomes Noise. a fix I found online is to kill the audio deamon on Mac OS, This works using the command: "sudo killall coreaudiod" this kills the audio process, (while the emulator is operational), then the macOS restarts the audio deamon then the audio works fine alongside with the simulator being open. I just want to ask is there a permanent fix for this? is Apple working on a fix for this in the upcoming update?
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After iPadOS 26 Beta and iOS 26 Beta, AVCaptureMetadataOutput no longer detects Face on some devices.
I'm creating an app that uses AVCaptureSession to pass camera input to AVCaptureMetadataOutput type set [metaout setMetadataObjectTypes:@[AVMetadataObjectTypeFace]] and scan Face. After updating to OS 26 Beta2 and iOS 26 Beta2, an issue has occurred where the delegate method of AVCaptureMetadataOutputObjectsDelegate is not called on some devices. The following devices are experiencing this issue. iPad (9th Gen) iPad air (4th Gen) iPhone 15 This issue has not occur on any other devices I have. I tried running the AVFoundation sample code on the Apple Developer site on the above device. The same problem still occurs. [https://developer.apple.com/documentation/avfoundation/capture_setup/avcambarcode_detecting_barcodes_and_faces] Are any additional settings required after OS 26 beta and iOS 26 beta? Or is there some problem on the OS side?
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Ventura Hack for FireWire Core Audio Support on Supported MacBook Pro and others...
Hi all,  Apple dropping on-going development for FireWire devices that were supported with the Core Audio driver standard is a catastrophe for a lot of struggling musicians who need to both keep up to date on security updates that come with new OS releases, and continue to utilise their hard earned investments in very expensive and still pristine audio devices that have been reduced to e-waste by Apple's seemingly tone-deaf ignorance in the cries for on-going support.  I have one of said audio devices, and I'd like to keep using it while keeping my 2019 Intel Mac Book Pro up to date with the latest security updates and OS features.  Probably not the first time you gurus have had someone make the logical leap leading to a request for something like this, but I was wondering if it might be somehow possible of shoe-horning the code used in previous versions of Mac OS that allowed the Mac to speak with the audio features of such devices to run inside the Ventura version of the OS.  Would it possible? Would it involve a lot of work? I don't think I'd be the only person willing to pay for a third party application or utility that restored this functionality. There has to be 100's of thousands of people who would be happy to spare some cash to stop their multi-thousand dollar investment in gear to be so thoughtlessly resigned to the scrap heap.  Any comments or layman-friendly explanations as to why this couldn’t happen would be gratefully received!  Thanks,  em
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SpeechAnalyzer speech to text wwdc sample app
I am using the sample app from: https://developer.apple.com/videos/play/wwdc2025/277/?time=763 I installed this on an Iphone 15 Pro with iOS 26 beta 1. I was able to get good transcription with it. The app did crash sometimes when transcribing and I was going to post here with the details. I then installed iOS beta 2 and uninstalled the sample app. Now every time I try to run the sample app on the 15 Pro I get this message: SpeechAnalyzer: Input loop ending with error: Error Domain=SFSpeechErrorDomain Code=10 "Cannot use modules with unallocated locales [en_US (fixed en_US)]" UserInfo={NSLocalizedDescription=Cannot use modules with unallocated locales [en_US (fixed en_US)]} I can't continue our our work towards using SpeechAnalyzer now with this error. I have set breakpoints on all the catch handlers and it doesn't catch this error. My phone region is "United States"
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SpeechAnalyzer error "asset not found after attempted download" for certain languages
I am trying to use the new SpeechAnalyzer framework in my Mac app, and am running into an issue for some languages. When I call AssetInstallationRequest.downloadAndInstall() for some languages, it throws an error: Error Domain=SFSpeechErrorDomain Code=1 "transcription.ar asset not found after attempted download." The ".ar" appears to be the language code, which in this case was Arabic. When I call AssetInventory.status(forModules:) before attempting the download, it is giving me a status of "downloading" (perhaps from an earlier attempt?). If this language was completely unsupported, I would expect it to return a status of "unsupported", so I'm not sure what's going on here. For other languages (Polish, for example) SpeechTranscriber.supportedLocale(equivalentTo:) is returning nil, so that seems like a clearly unsupported language. But I can't tell if the languages I'm trying, like Arabic, are supported and something is going wrong, or if this error represents something I can work around. Here's the relevant section of code. The error is thrown from downloadAndInstall(), so I never even get as far as setting up the SpeechAnalyzer itself. private func setUpAnalyzer() async throws { guard let sourceLanguage else { throw Error.languageNotSpecified } guard let locale = await SpeechTranscriber.supportedLocale(equivalentTo: Locale(identifier: sourceLanguage.rawValue)) else { throw Error.unsupportedLanguage } let transcriber = SpeechTranscriber(locale: locale, preset: .progressiveTranscription) self.transcriber = transcriber let reservedLocales = await AssetInventory.reservedLocales if !reservedLocales.contains(locale) && reservedLocales.count == AssetInventory.maximumReservedLocales { if let oldest = reservedLocales.last { await AssetInventory.release(reservedLocale: oldest) } } do { let status = await AssetInventory.status(forModules: [transcriber]) print("status: \(status)") if let installationRequest = try await AssetInventory.assetInstallationRequest(supporting: [transcriber]) { try await installationRequest.downloadAndInstall() } } ...
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CoreMediaErrorDomain error -12848
Good day. A video I created via iOS AVAssetWriter with the following settings: let videoWriterInput = AVAssetWriterInput( mediaType: .video, outputSettings: [ AVVideoCodecKey: AVVideoCodecType.hevc, AVVideoWidthKey: 1080, AVVideoHeightKey: 1920, AVVideoCompressionPropertiesKey: [ AVVideoAverageBitRateKey: 2_000_000, AVVideoMaxKeyFrameIntervalKey: 30 ], ] ) let audioWriterInput = AVAssetWriterInput( mediaType: .audio, outputSettings: [ AVFormatIDKey: kAudioFormatMPEG4AAC, AVNumberOfChannelsKey: 2, AVSampleRateKey: 44100, AVEncoderBitRateKey: 128000 ] ) When It is split into fMP4 HLS format using ffmpeg, the video is unable to be played in iOS with the following error: CoreMediaErrorDomain error -12848 However, the video is played normally in Android, Browser HLS players, and also VLC Media Player. Please assist. Thank you.
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Unabe to use writeHEIFRepresentation - failed to add image to the PhotoCompressionSession.
I'm getting an error writing a ciImage as a heif image: // Create CIImage directly from pixel buffer let ciImage = CIImage(cvPixelBuffer: pixelBuffer, options: [CIImageOption.properties: combinedMetadata]) // Write HEIC synchronously do { try ciContext.writeHEIFRepresentation(of: ciImage, to: url, format: .RGBA8, colorSpace: colorSpace) The error I'm getting is: Error Domain=CINonLocalizedDescriptionKey Code=3 "(null)" UserInfo={CINonLocalizedDescriptionKey=failed to write HEIC data to file., NSUnderlyingError=0x11b1a1ec0 {Error Domain=CINonLocalizedDescriptionKey Code=10 "(null)" UserInfo={CINonLocalizedDescriptionKey=failed to add image to the PhotoCompressionSession.}}} Both try ciContext.writeJPEGRepresentation(of: copiedCIImage, to: url, colorSpace: colorSpace, options: options) and try ciContext.writePNGRepresentation(of: copiedCIImage, to: url, format: .RGBA8, colorSpace: colorSpace) work. I also verified that the code works with iOS 18. Is there something new we need to do for Heif images? Thanks in advance
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iOS26中ALAssetsLibrary 编译报错问题
mac os 系统版本:26.0 (25A354) Xcode版本:Version 26.0 (17A324) 项目编译报错 `SwiftExplicitDependencyCompileModuleFromInterface arm64 /Users/zhz/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/AssetsLibrary-HTIJ05N58KN3.swiftmodule /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:10:25: error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead 8 | public import _StringProcessing 9 | public import _SwiftConcurrencyShims 10 | extension AssetsLibrary.ALAssetsLibrary { | `- error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead 11 | #if compiler(>=5.3) && $NonescapableTypes 12 | @available(iOS, introduced: 9.0, deprecated: 9.0, obsoleted: 26.0) /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/System/Library/Frameworks/AssetsLibrary.framework/Headers/ALAssetsLibrary.h:80:12: note: 'ALAssetsLibrary' was obsoleted in iOS 26.0 78 | 79 | OS_EXPORT AL_DEPRECATED(4, "Use PHPhotoLibrary from the Photos framework instead") 80 | @interface ALAssetsLibrary : NSObject { | `- note: 'ALAssetsLibrary' was obsoleted in iOS 26.0 81 | @package 82 | id _internal; /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:1:1: error: failed to build module 'AssetsLibrary'; this SDK is not supported by the compiler (the SDK is built with 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.17.14 clang-1700.3.17.1)', while this compiler is 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.19.9 clang-1700.3.19.1)'). Please select a toolchain which matches the SDK.
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AVCaptureMetadataOutput .face detection not working on iOS 26 Beta with high sessionPreset
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.
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High shutter speed with low frame rate and auto exposure
Hi there, I want to set the iphone camera to "S mode, or Shutter Priority" in camera terminology. Which is a semi-auto exposure model with shutter speed fixed, or set manually. However, when setting the shutter speed manually, it disables the auto exposure. So is there a way to keep the auto exposure on while restrict the shutter speed? Also, I would like to keep a low frame rate, e.g. 30 fps. Would I be able to set shutter speed independent of frame rate? Here's the code for setting up the camera Best,
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Crash iOS 26.0: [__NSSingleObjectArrayI selectedMediaOptionInMediaSelectionGroup:]: unrecognized selector sent to instance
I'm having a crash on an app that plays videos when the users activates close captions. I was able to replicate the issue on an empty project. The crash happens when the AVPlayerLayer is used to instantiate an AVPictureInPictureController These are the example project where I tested the crash: struct ContentView: View { var body: some View { VStack { VideoPlaylistView() } .frame(maxWidth: .infinity, maxHeight: .infinity) .background(Color.black.ignoresSafeArea()) } } class VideoPlaylistViewModel: ObservableObject { // Test with other videos var player: AVPlayer? = AVPlayer(url: URL(string:"https://d2ufudlfb4rsg4.cloudfront.net/newsnation/WIpkLz23h/adaptive/WIpkLz23h_master.m3u8")!) } struct VideoPlaylistView: View { @StateObject var viewModel = VideoPlaylistViewModel() var body: some View { ScrollView { VideoCellView(player: viewModel.player) .onAppear { viewModel.player?.play() } } .scrollTargetBehavior(.paging) .ignoresSafeArea() } } struct VideoCellView: View { let player: AVPlayer? @State var isCCEnabled: Bool = false var body: some View { ZStack { PlayerView(player: player) .accessibilityIdentifier("Player View") } .containerRelativeFrame([.horizontal, .vertical]) .overlay(alignment: .bottom) { Button { player?.currentItem?.asset.loadMediaSelectionGroup(for: .legible) { group,error in if let group { let option = !isCCEnabled ? group.options.first : nil player?.currentItem?.select(option, in: group) isCCEnabled.toggle() } } } label: { Text("Close Captions") .font(.subheadline) .foregroundStyle(isCCEnabled ? .red : .primary) .buttonStyle(.bordered) .padding(8) .background(Color.blue.opacity(0.75)) } .padding(.bottom, 48) .accessibilityIdentifier("Button Close Captions") } } } import Foundation import UIKit import SwiftUI import AVFoundation import AVKit struct PlayerView: UIViewRepresentable { let player: AVPlayer? func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<PlayerView>) { } func makeUIView(context: Context) -> UIView { let view = PlayerUIView() view.playerLayer.player = player view.layer.addSublayer(view.playerLayer) view.layer.backgroundColor = UIColor.red.cgColor view.pipController = AVPictureInPictureController(playerLayer: view.playerLayer) view.pipController?.requiresLinearPlayback = true view.pipController?.canStartPictureInPictureAutomaticallyFromInline = true view.pipController?.delegate = view return view } } class PlayerUIView: UIView, AVPictureInPictureControllerDelegate { let playerLayer = AVPlayerLayer() var pipController: AVPictureInPictureController? override init(frame: CGRect) { super.init(frame: frame) } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } override func layoutSubviews() { super.layoutSubviews() playerLayer.frame = bounds playerLayer.backgroundColor = UIColor.green.cgColor } func pictureInPictureController(_ pictureInPictureController: AVPictureInPictureController, failedToStartPictureInPictureWithError error: any Error) { print("Error starting Picture in Picture: \(error.localizedDescription)") } } class AppDelegate: NSObject, UIApplicationDelegate { func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool { let audioSession = AVAudioSession.sharedInstance() do { try audioSession.setCategory(.playback, mode: .moviePlayback) try audioSession.setActive(true) } catch { print("ERR: \(error.localizedDescription)") } return true } } UITest to make the app crash: final class VideoPlaylistSampleUITests: XCTestCase { func testCrashiOS26ToggleCloseCaptions() throws { let app = XCUIApplication() app.launch() let videoPlayer = app.otherElements["Player View"] XCTAssertTrue(videoPlayer.waitForExistence(timeout: 30)) let closeCaptionButton = app.buttons["Button Close Captions"] for _ in 0..<2000 { closeCaptionButton.tap() } } }
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AVPlayer loading performance problem in iOS 26
Hi, I have an app that displays tens of short (<1mb) mp4 videos stored in a remote server in a vertical UICollectionView that has horizontally scrollable sections. I'm caching all mp4 files on disk after downloading, and I also have a in-memory cache that holds a limited number (around 30) of players. The players I'm using are simple views that wrap an AVPlayerLayer and its AVPlayerItem, along with a few additional UI components. The scrolling performance was good before iOS 26, but with the release of iOS 26, I noticed that there is significant stuttering during scrolling while creating players with a fileUrl. It happens even if use the same video file cached on disk for each cell for testing. I also started getting this kind of log messages after the players are deinitialized: <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1107 <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1095 <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1095 There's also another log message that I see occasionally, but I don't know what triggers it. << FigXPC >> signalled err=-16152 at <>:1683 Is there anyone else that experienced this kind of problem with the latest release? Also, I'm wondering what's the best way to resolve the issue. I could increase the size of the memory cache to something large like 100, but I'm not sure if it is an acceptable solution because: 1- There will be 100 player instance in memory at all times. 2- There will still be stuttering during the initial loading of the videos from the web. Any help is appreciated!
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Blurry Depth Data since iPhone 13
I tested the accuracy of the depth map on iPhone 12, 13, 14, 15, and 16, and found that the variance of the depth map after iPhone 12 is significantly greater than that of iPhone 12. Enabling depth filtering will cause the depth data to be affected by the previous frame, adding more unnecessary noise, especially when the phone is moving. This is not friendly for high-precision reconstruction. I tried to add depth map smoothing in post-processing to solve the problem of large depth map deviation, but the performance is still poor. Is there any depth map smoothing solutions already announced by Apple?
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How can I create my own Genlock hardware for the iPhone 17 Pro?
What options do I have if I don't want to use Blackmagic's Camera ProDock as the external Sync Hardware, but instead I want to create my own USB-C hardware accessory which would show up as an AVExternalSyncDevice on the iPhone 17 Pro? Which protocol does my USB-C device have to implement to show up as an eligible clock device in AVExternalSyncDevice.DiscoverySession?
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AudioQueue Output fails playing audio almost immediately?
On macOS Sequoia, I'm having the hardest time getting this basic audio output to work correctly. I'm compiling in XCode using C99, and when I run this, I get audio for a split second, and then nothing, indefinitely. Any ideas what could be going wrong? Here's a minimum code example to demonstrate: #include &lt;AudioToolbox/AudioToolbox.h&gt; #include &lt;stdint.h&gt; #define RENDER_BUFFER_COUNT 2 #define RENDER_FRAMES_PER_BUFFER 128 // mono linear PCM audio data at 48kHz #define RENDER_SAMPLE_RATE 48000 #define RENDER_CHANNEL_COUNT 1 #define RENDER_BUFFER_BYTE_COUNT (RENDER_FRAMES_PER_BUFFER * RENDER_CHANNEL_COUNT * sizeof(f32)) void RenderAudioSaw(float* outBuffer, uint32_t frameCount, uint32_t channelCount) { static bool isInverted = false; float scalar = isInverted ? -1.f : 1.f; for (uint32_t frame = 0; frame &lt; frameCount; ++frame) { for (uint32_t channel = 0; channel &lt; channelCount; ++channel) { // series of ramps, alternating up and down. outBuffer[frame * channelCount + channel] = 0.1f * scalar * ((float)frame / frameCount); } } isInverted = !isInverted; } AudioStreamBasicDescription coreAudioDesc = { 0 }; AudioQueueRef coreAudioQueue = NULL; AudioQueueBufferRef coreAudioBuffers[RENDER_BUFFER_COUNT] = { NULL }; void coreAudioCallback(void* unused, AudioQueueRef queue, AudioQueueBufferRef buffer) { // 0's here indicate no fancy packet magic AudioQueueEnqueueBuffer(queue, buffer, 0, 0); } int main(void) { const UInt32 BytesPerSample = sizeof(float); coreAudioDesc.mSampleRate = RENDER_SAMPLE_RATE; coreAudioDesc.mFormatID = kAudioFormatLinearPCM; coreAudioDesc.mFormatFlags = kLinearPCMFormatFlagIsFloat | kLinearPCMFormatFlagIsPacked; coreAudioDesc.mBytesPerPacket = RENDER_CHANNEL_COUNT * BytesPerSample; coreAudioDesc.mFramesPerPacket = 1; coreAudioDesc.mBytesPerFrame = RENDER_CHANNEL_COUNT * BytesPerSample; coreAudioDesc.mChannelsPerFrame = RENDER_CHANNEL_COUNT; coreAudioDesc.mBitsPerChannel = BytesPerSample * 8; coreAudioQueue = NULL; OSStatus result; // most of the 0 and NULL params here are for compressed sound formats etc. result = AudioQueueNewOutput(&amp;coreAudioDesc, &amp;coreAudioCallback, NULL, 0, 0, 0, &amp;coreAudioQueue); if (result != noErr) { assert(false == "AudioQueueNewOutput failed!"); abort(); } for (int i = 0; i &lt; RENDER_BUFFER_COUNT; ++i) { uint32_t bufferSize = coreAudioDesc.mBytesPerFrame * RENDER_FRAMES_PER_BUFFER; result = AudioQueueAllocateBuffer(coreAudioQueue, bufferSize, &amp;(coreAudioBuffers[i])); if (result != noErr) { assert(false == "AudioQueueAllocateBuffer failed!"); abort(); } } for (int i = 0; i &lt; RENDER_BUFFER_COUNT; ++i) { RenderAudioSaw(coreAudioBuffers[i]-&gt;mAudioData, RENDER_FRAMES_PER_BUFFER, RENDER_CHANNEL_COUNT); coreAudioBuffers[i]-&gt;mAudioDataByteSize = coreAudioBuffers[i]-&gt;mAudioDataBytesCapacity; AudioQueueEnqueueBuffer(coreAudioQueue, coreAudioBuffers[i], 0, 0); } AudioQueueStart(coreAudioQueue, NULL); sleep(10); // some time to hear the audio AudioQueueStop(coreAudioQueue, true); AudioQueueDispose(coreAudioQueue, true); return 0; }
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Metal CIKernel instances with arbitrarily structured data arguments
Hi, In the iOS13 and macOS Catalina release notes it says: Metal CIKernel instances now support arguments with arbitrarily structured data. I've been trying to use this functionality in a CIKernel with mixed results. I'm particularly interested in passing data in the form of a dynamically sized array. It seems to work up to a certain size. Beyond the threshold excessive data is discarded and the kernel becomes unstable. I assume there is some kind of memory alignment issue going on, but I've tried various types in my array and always get a similar result. I have not found any documentation or sample code regarding this. It would be great to know how this is intended to work and what the limitations are. In the forums there are two similar unanswered questions about data arguments, so I'm sure there are a few out there with similar issues. Thanks! Michael
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donate INPlayMediaIntent to systerm, but not show in control center
I donate INPlayMediaIntent to systerm(donate success), but not show in control center My code is as follows let mediaItems = mediaItems.map { $0.inMediaItem } let intent = if #available(iOS 13.0, *) { INPlayMediaIntent(mediaItems: mediaItems, mediaContainer: nil, playShuffled: false, playbackRepeatMode: .none, resumePlayback: true, playbackQueueLocation: .now, playbackSpeed: nil, mediaSearch: nil) } else { INPlayMediaIntent(mediaItems: mediaItems, mediaContainer: nil, playShuffled: false, playbackRepeatMode: .none, resumePlayback: true) } intent.suggestedInvocationPhrase = "播放音乐" let interaction = INInteraction(intent: intent, response: nil) interaction.donate { error in if let error = error { print("Intent 捐赠失败: \(error.localizedDescription)") } else { print("Intent 捐赠成功 ✅") } }
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