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?

In SwiftUI there is a built-in component for displaying album artworks called Artwork but there is no equivalent for UIKit. My current approach is to use the .url() method to read image's URL and download the image or read it from the disk but the performance is much worse than it was previously with MPMediaItem's artworkImage method. let artworkQueue = DispatchQueue( label: "MusicKit-ArtworkQueue", qos: .default, attributes: .concurrent ) let artworkSemaphore = DispatchSemaphore(value: 5) extension Song { func artworkImage(for size: CGSize, completion: @escaping (UIImage?) -> Void) { artworkQueue.async { artworkSemaphore.wait() defer { artworkSemaphore.signal() } let imageURL = artwork?.url( width: Int(size.width), height: Int(size.height) ) // I hate doing this as it might very well break in the future guard let imageURL, imageURL.scheme == "musicKit" else { return completion(nil) } guard let imageData = try? Data(contentsOf: imageURL), let image = UIImage(data: imageData) else { return completion(nil) } completion(image) } } } I really dislike this approach because it feels hacky but somewhat works. You might ask what's the semaphore for? Well, without it I could notice that MusicKit was choking and after reading too many artworks at once. Can someone from Apple please provide us with an example on how to use MusicKit with UIKit properly? Ideally (IMO) we would have a method defined on Song and other MusicKit structures that returns the image for us, just like MPMediaItem had the .artwork() method. It would make our lives so much easier.

I’m building a SwiftUI app whose primary job is to play audio. I manage all of the Now-Playing metadata and Command center manually via the available shared instances: MPRemoteCommandCenter.shared() MPNowPlayingInfoCenter.default().nowPlayingInfo In certain parts of the app I also need to display videos, but as soon as I attach another AVPlayer, it automatically pushes its own metadata into the Control Center and overwrites my audio info. What I need: a way to show video inline without ever having that video player update the system’s Now-Playing info (or Control Center). In my app, I start by configuring the shared audio session do { try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [ .allowAirPlay, .allowBluetoothA2DP ]) try AVAudioSession.sharedInstance().setActive(true) } catch { NSLog("%@", "**** Failed to set up AVAudioSession \(error.localizedDescription)") } and then set the MPRemoteCommandCenter commands and MPNowPlayingInfoCenter nowPlayingInfo like mentioned above. All this works without any issues as long as I only have one AVPlayer in my app. But when I add other AVPlayers to display some videos (and keep the main AVPlayer for the sound) they push undesired updates to MPNowPlayingInfoCenter: struct VideoCardView: View { @State private var player: AVPlayer let videoName: String init(player: AVPlayer = AVPlayer(), videoName: String) { self.player = player self.videoName = videoName guard let path = Bundle.main.path(forResource: videoName, ofType: nil) else { return } let url = URL(fileURLWithPath: path) let item = AVPlayerItem(url: url) self.player.replaceCurrentItem(with: item) } var body: some View { VideoPlayer(player: player) .aspectRatio(contentMode: .fill) .onAppear { player.isMuted = true player.allowsExternalPlayback = false player.actionAtItemEnd = .none player.play() MPNowPlayingInfoCenter.default().nowPlayingInfo = nil MPNowPlayingInfoCenter.default().playbackState = .stopped NotificationCenter.default.addObserver(forName: .AVPlayerItemDidPlayToEndTime, object: player.currentItem, queue: .main) { notification in guard let finishedItem = notification.object as? AVPlayerItem, finishedItem === player.currentItem else { return } player.seek(to: .zero) player.play() } } .onDisappear { player.pause() } } } Which is why I tried adding: MPNowPlayingInfoCenter.default().nowPlayingInfo = nil MPNowPlayingInfoCenter.default().playbackState = .stopped // or .interrupted, .unknown But that didn't work. I also tried making a wrapper around the AVPlayerViewController in order to set updatesNowPlayingInfoCenter to false, but that didn’t work either: struct CustomAVPlayerView: UIViewControllerRepresentable { let player: AVPlayer func makeUIViewController(context: Context) -> AVPlayerViewController { let vc = AVPlayerViewController() vc.player = player vc.updatesNowPlayingInfoCenter = false vc.showsPlaybackControls = false return vc } func updateUIViewController(_ controller: AVPlayerViewController, context: Context) { controller.player = player } } Hence any help on how to embed video in SwiftUI without its AVPlayer touching MPNowPlayingInfoCenter would be greatly appreciated. All this was tested on an actual device with iOS 18.4.1, and built with Xcode 16.2 on macOS 15.5

Hello, I am trying to get the new iPhone 16 pro to achieve 4k 120fps encoding when we are getting the video feed from the default, wide angle camera on the back. We are using the apple API to capture the individual frames from the camera as they are processed and we get them in this callback: // this is the main callback function to handle video frames captured func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) { We are then taking these frames as they come in and encoding them using VideoToolBox. After they are encoded, they are added to a ring buffer so we can access them after they have been encoded. The problem is that when we are encoding these frames on an iPhone 16 Pro, we are only reaching 80-90fps instead of 120fps. We have removed as much processing as we can. We get some small attributes about the frame when it comes in, encode the frame, and then add it to our ring buffer. I have attached a sample project that is broken down as much as possible to the basic task of encoding 4k 120fps footage. Inside the sample app, there is an fps and pps display showing how many frames we are encoding per second. FPS represents how many frames we are coming in per second from the camera, and PPS represents how many frames we are processing (encoding) per second. Link to sample project: https://github.com/jake-fishtech/EncoderPerformance Thanks you for any help or suggestions.

The same H265 encrypted Fairplay content can be played in all Apple devices except A1625. The clear H265 content is played in A1625. The question is: will this model (A1625) support H265 Fairplay encrypted content? A ticket was created here: https://discussions.apple.com/thread/255658006?sortBy=best

I often find when doing basic actions in MusicKit it is incredibly slow compared to Apple's Music App. I've tried different versions, devices, networks, Apple's sample code, it all throughout the last several years, and it is all the same. Does anyone else have this issue?

TL;DR How to solve possible racing issue of EXT-X-SESSION-KEY request and encrypted media segment request? I'm having trouble using custom AVAssetResourceLoaderDelegate with video manifest containing VideoProtectionKey(VPK). My master manifest contains rendition manifest url and VPK url. When not using custom resource delegate, everything works fine. My custom resource delegate is implemented in way where it first append prefix to scheme of the master manifest url before creating the asset. And during handling master manifest, it puts back original scheme, make the request, modify the scheme for rendition manifest url in the response content by appending the same prefix again, so that rendition manifest request also goes into custom resource loader delegate. Same goes for VPK request. The AES-128 key is stored in memory within custom resource loader delegate object. So far so good. The VPK is requested before segment request. But the problem comes where the media segment requests happen. The media segment request url from rendition manifest goes into custom resource loader as well and those are encrypted. I can see segment request finish first then the related VPK requests kick in after a few seconds. The previous VPK value is cached in memory so it is not network causing the delay but some mechanism that I'm not aware of causing this. So could anyone tell me what would be the proper way of handling this situation? The native library is handling it well so I just want to know how. Thanks in advance!

The presentation "create audio drivers with DriverKit" from WWDC 2021 demonstrates how to use a dext to implement a virtual audio driver. It also says " If a virtual audio driver or device is all that is needed, the audio server plug-in driver model should continue to be used". Indeed, in AudioDriverKit/AudioDriverKitTypes.h, there is no IOUserAudioTransportType Virtual, although CoreAudio/AudioHardwareBase.h includes kAudioDeviceTransportTypeVirtual. For one of our products, we require virtual devices to implement a software loopback "cable". We've implemented this using the "traditional" HAL plugin, and as a proof-of-concept, also using a dext. In the dext, I tried setting the transport type to 'virt', which seems to only have the effect of changing the icon shown in Audio Midi Setup. HAL plugins require an installer, and the installer has to kill coreaudiod in a post-install script. You have to turn off SIP to debug them. Just like AudioDriverKit drivers, they are out-of-process and run in a process not owned by the hosting app. Our HAL plugin's interface is property based; we had to write a lot of boiler-plate code to implement required properties. Writing an AudioDriverKit driver is in most respects easier - a lot of the scaffolding is implemented in the base driver, which we only alter where required. Debugging and installation is much easier. The dext works just fine, as far as we can ascertain, just as well as a HAL plugin. So, my question is - is the advice to use a HAL plugin for a virtual device still correct in 2025? And if so, what's the objection? We'd really prefer to ship the AudioDriverKit virtual audio device.

I'm getting this error when I launch my application on the iPhone 14 Pro via Xcode. Everything builds OK. I"m using the audio kit plugin and Sound Pipe Audiokit. The error starts as soon as I start the app and will carry on repeatedly. I have background processing turned on as I'd like the sounds to play when the phone is locked via the headphones. I can't find anything online about this error. None of my catches are printing anything in the logs either. So I don't know if this is just something that pops up repeatedly or whether there is something fundamentally wrong. private func setupAudioSession() { do { let session = AVAudioSession.sharedInstance() try session.setCategory(.playback, mode: .default, options: [.mixWithOthers]) try session.setActive(true, options: .notifyOthersOnDeactivation) } catch { errorMessage = "Failed to set up audio session: (error.localizedDescription)" print(errorMessage ?? "") } } // MARK: - Background Task Handling private func setupBackgroundTaskHandling() { // Handle app entering background notificationObservers.append( NotificationCenter.default.addObserver( forName: UIApplication.didEnterBackgroundNotification, object: nil, queue: .main, using: { [weak self] _ in // Safely unwrap self guard let self = self else { return } self.handleBackgroundTransition() } ) ) I'm not sure if this is the code causing the issue. Any help would be gratefully appreciated. This is my first app I'm working on .

Hello, I'm sporadically getting the unknown CoreHaptics error described in the title, when trying to create a CHHapticPatternPlayer from an .ahap file — this does not occur in a repeatable manner, unfortunately... This occurs in a SpriteKit game, running on both iOS 17 and 18. Anyone know what the error means, since it's apparently undocumented? Note that the haptics engine is started right before creating the pattern, and the start request doesn't appear to fail... Thanks, D.

Hi, I am getting into a trap. Please check stack-trace, howto fix this? regards, Joël stack-trace with ExtAudioFileWrite

FxPlug is one of Apple’s official SDKs, recently updated to version 4.3.2. In theory the SDK should guarantee third-parties can build plug-ins that are backward compatible with older versions of Final Cut Pro, Motion and Compressor. FxPlug SDK includes two frameworks that third-party developers like me end up bundling inside our third-party plugins: FxPlug.framework and PlugInManager.framework. Behind the scenes, the SDK relies on PlugInKit, but the FxPlug.framework provides abstractions so that third-parties don't have to handle the intricacies of XPC directly. The most recent version of FxPlug.framework included with the SDK was possibly built with an error: the Info.plist shows a LSMinimumSystemVersion entry of 14.6, suggesting the binary may have been compiled and linked with MACOSX_DEPLOYMENT_TARGET set to 14.6 by accident. The problem: when older versions of Final Cut Pro or Motion load a third-party plugin (itself built with the appropriate deployment target, macOS 11 or 12, for example) on pre-macOS 14.6, the dynamic linker immediately loads Apple’s own FxPlug.framework, but this causes the process to crash immediately: Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 libobjc.A.dylib 0x7ff81e065955 map_images_nolock + 5399 1 libobjc.A.dylib 0x7ff81e0643d6 map_images + 67 2 dyld 0x10bd551fb invocation function for block in dyld4::RuntimeState::setObjCNotifiers(void (*)(unsigned int, char const* const*, mach_header const* const*), void (*)(char const*, mach_header const*), void (*)(char const*, mach_header const*)) + 275 3 dyld 0x10bd506c9 dyld4::RuntimeState::withLoadersReadLock(void () block_pointer) + 41 4 dyld 0x10bd550e2 dyld4::RuntimeState::setObjCNotifiers(void (*)(unsigned int, char const* const*, mach_header const* const*), void (*)(char const*, mach_header const*), void (*)(char const*, mach_header const*)) + 82 5 dyld 0x10bd68d45 dyld4::APIs::_dyld_objc_notify_register(void (*)(unsigned int, char const* const*, mach_header const* const*), void (*)(char const*, mach_header const*), void (*)(char const*, mach_header const*)) + 79 6 libobjc.A.dylib 0x7ff81e064244 _objc_init + 1279 7 libdispatch.dylib 0x7ff81e01d993 _os_object_init + 13 8 libdispatch.dylib 0x7ff81e02b1b8 libdispatch_init + 311 9 libSystem.B.dylib 0x7ff828fd585f libSystem_initializer + 238 10 dyld 0x10bd5ae4f invocation function for block in dyld4::Loader::findAndRunAllInitializers(dyld4::RuntimeState&) const + 182 11 dyld 0x10bd81aad invocation function for block in dyld3::MachOAnalyzer::forEachInitializer(Diagnostics&, dyld3::MachOAnalyzer::VMAddrConverter const&, void (unsigned int) block_pointer, void const*) const + 242 12 dyld 0x10bd78e26 invocation function for block in dyld3::MachOFile::forEachSection(void (dyld3::MachOFile::SectionInfo const&, bool, bool&) block_pointer) const + 557 13 dyld 0x10bd47db3 dyld3::MachOFile::forEachLoadCommand(Diagnostics&, void (load_command const*, bool&) block_pointer) const + 129 14 dyld 0x10bd78bb7 dyld3::MachOFile::forEachSection(void (dyld3::MachOFile::SectionInfo const&, bool, bool&) block_pointer) const + 179 15 dyld 0x10bd81604 dyld3::MachOAnalyzer::forEachInitializer(Diagnostics&, dyld3::MachOAnalyzer::VMAddrConverter const&, void (unsigned int) block_pointer, void const*) const + 466 16 dyld 0x10bd5ad82 dyld4::Loader::findAndRunAllInitializers(dyld4::RuntimeState&) const + 144 17 dyld 0x10bd6165a dyld4::PrebuiltLoader::runInitializers(dyld4::RuntimeState&) const + 30 18 dyld 0x10bd6e76e dyld4::APIs::runAllInitializersForMain() + 38 19 dyld 0x10bd4c38d dyld4::prepare(dyld4::APIs&, dyld3::MachOAnalyzer const*) + 3443 20 dyld 0x10bd4b4e4 start + 388 Can someone at Apple with the right domain expertise confirm that this is the type of crash you would see because the framework was built assuming it would run on macOS 14.6 and later, and when facing an older environment (e.g. ObjC runtime) it lacks extra code that would ensure backward compatibility with the earlier ObjC runtime found on macOS 12.x?

I'm trying to implement airplay into my app. I can successfully playback sound and trigger the airplay selector sheet. If the target device is a Bluetooth only device I can connect with no problem and stream the audio to the Bluetooth device, but if the audio device is a airplay specific device like a HomePod or an Apple TV when I select it, I get a spinning icon, indicating that it is trying to connect, and eventually it times out and stops without connecting. I don't believe it is an AirPlay audio issue because if I go to a different app, for example a podcast app and select my HomePods for output, and then switch back to my app. My audio will correctly stream to the HomePod. Not only that, I have it so that my icon will change color to indicate that it is connected via airplay and it is correctly indicating that it is connected via AirPlay. But I cannot then disconnect it using the Airplay selector. The issue appears to be in the AirPlay selection side, which I have spent several days attempting to troubleshoot mostly using ChatGPT to suggest code different than what I have to maybe work around the issue. Mostly it is focused on the audio player section, but it doesn't seem like that is really the route that is the problem.

Hello, I am getting the following error while attempting to run my LockedCameraCapture compatible app on an iOS 15 device: dyld[434]: Library not loaded: '/System/Library/Frameworks/LockedCameraCapture.framework/LockedCameraCapture' Referenced from: '/private/var/containers/Bundle/Application/.../MyApp.app/MyApp.debug.dylib' Reason: tried: '/System/Library/Frameworks/LockedCameraCapture.framework/LockedCameraCapture' (no such file) Of course iOS 15 doesn't have the library for LockedCameraCapture, but I have had no issue including Lock Screen Widgets (which require iOS 16), so I am not sure why the error is popping up. Thank you!

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

I use AVPlayer to play HLS video successfully on macOS Sonoma, but I encountered this error on macOS Sequoia. Please help me: Error Domain=AVFoundationErrorDomain Code=-11833 ‘Cannot Decode’ UserInfo={NSUnderlyingError=0x600001e57330 {Error Domain=CoreMediaErrorDomain Code=-12906 ‘(null)’}, NSLocalizedFailureReason=The decoder required for this media cannot be found., AVErrorMediaTypeKey=vide, NSLocalizedDescription=Cannot Decode} Thanks!

I’ve never had a problem with any update before but as soon as I updated to 18.3 update my camera decided to start blurring when it’s in 1x & 2x, I use my camera daily for work and this is unacceptable. I’m wondering if anyone else is having this issue, it’s really frustrating..

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?

After upgrading to iOS 18.4, I'm no longer able to establish an AirPlay v1 connection to an audio system. The symptom is that the AirPlay route picker just spins when trying to connect to an audio system. It eventually gives up. I tested this on an iPhone 14, connecting to a HomePod, AirPort express, AppleTV and a Wiim Pro. If I try connecting with AirPlay v2, ex: using Apple Music, the connection succeeds and audio can be played. I'm the developer of an app that plays audio over AirPlay while also recording. My app has to use AirPlay v1 because AvAudioSession doesn't allow the policy .longFormAudio when the category is .playAndRecord. This issue is a real pain as it means my app is suddenly broken for many thousands of users. Is anyone else seeing this issue? Any suggestions for a workaround?

Safari is supposed to support animated AVIF images since version 16, but the ones I've tested perform very poorly, even on an M4 Mac Mini running Sequoia 15.1.1. I believe Safari delegates decoding to the operating system itself, so this issue also happens in Live Preview in the finder, when I try to preview a file. Sample file here: https://s3.us-west-2.amazonaws.com/cdn.paintera.org/test/sample.avif 322KB file, 5 seconds long, 12fps This plays perfectly on Chrome on Mac OS, but is slow and laggy on Safari and Live Preview (it takes about 6.5 seconds to finish the 5 second video). Does anyone know how to fix this or workaround this issue?