Hi all, with my app ScreenFloat, you can record your screen, along with system- and microphone audio. Those two audio feeds are recorded into separate audio tracks in order to individually remove or edit them later on. Now, these recordings you create with ScreenFloat can be drag-and-dropped to other apps instantly. So far, so good, but some apps, like Slack, or VLC, or even websites like YouTube, do not play back multiple audio tracks, just one. So what I'm trying to do is, on dragging the video recording file out of ScreenFloat, instantly baking together the two individual audio tracks into one, and offering that new file as the drag and drop file, so that all audio is played in the target app. But it's slow. I mean, it's actually quite fast, but for drag and drop, it's slow. My approach is this: "Bake together" the two audio tracks into a one-track m4a audio file using AVMutableAudioMix and AVAssetExportSession Take the video track, add the new audio file as an audio track to it, and render that out using AVAssetExportSession For a quick benchmark, a 3'40'' movie, step 1 takes ~1.7 seconds, and step two adds another ~1.5 seconds, so we're at ~3.2 seconds. That's an eternity for a drag and drop, where the user might cancel if there's no immediate feedback. I could also do it in one step, but then I couldn't use the AV*Passthrough preset, and that makes it take around 32 seconds then, because I assume it touches the video data (which is unnecessary in this case, so I think the two-step approach here is the fastest). So, my question is, is there a faster way? The best idea I can come up with right now is, when initially recording the screen with system- and microphone audio as separate tracks, to also record both of them into a third, muted, "hidden" track I could use later on, basically eliminating the need for step one and just ripping the two single audio tracks out of the movie and only have the video and the "hidden" track (then unmuted), but I'd still have a ~1.5 second delay there. Also, there's the processing and data overhead (basically doubling the movie's audio data). All this would be great for an export operation (where one expects it to take a little time), but for a drag-and-drop operation, it's not ideal. I've discarded the idea of doing a promise file drag, because many apps do not accept those, and I want to keep wide compatibility with all sorts of apps. I'd appreciate any ideas or pointers. Thank you kindly, Matthias

I am using AVMulti so the user captures two images how can I access those images if there is only one url that stores the captured images for the lockScreenCapture extension ? Plus how can I detect if the user opened the app from the extension to be able to navigate the user to the right screen ?

I'm developing an iOS app using AVFoundation for real-time video capture and object detection. While implementing torch functionality with camera switching (between Wide and Ultra-Wide lenses), I encountered a critical issue where the camera freezes when toggling the torch while the Ultra-Wide camera is active. Issue If the torch is ON and I switch from Wide to Ultra-Wide, the camera freezes If the Ultra-Wide camera is active and I try to turn the torch ON, the camera freezes The iPhone Camera app allows using the torch while recording video with the Ultra-Wide lens, so this should be possible via AVFoundation as well. Code snippet DispatchQueue.global(qos: .userInitiated).async { [weak self] in guard let self = self else { return } let isSwitchingToUltraWide = !self.isUsingFisheyeCamera let cameraType: AVCaptureDevice.DeviceType = isSwitchingToUltraWide ? .builtInUltraWideCamera : .builtInWideAngleCamera let cameraName = isSwitchingToUltraWide ? "Ultra Wide" : "Wide" guard let selectedCamera = AVCaptureDevice.default(cameraType, for: .video, position: .back) else { DispatchQueue.main.async { self.showAlert(title: "Camera Error", message: "\(cameraName) camera is not available on this device.") } return } do { let currentInput = self.videoCapture.captureSession.inputs.first as? AVCaptureDeviceInput self.videoCapture.captureSession.beginConfiguration() if isSwitchingToUltraWide && self.isFlashlightOn { self.forceEnableTorchThroughWide() } if let currentInput = currentInput { self.videoCapture.captureSession.removeInput(currentInput) } let videoInput = try AVCaptureDeviceInput(device: selectedCamera) self.videoCapture.captureSession.addInput(videoInput) self.videoCapture.captureSession.commitConfiguration() self.videoCapture.updateVideoOrientation() DispatchQueue.main.async { if let barButton = sender as? UIBarButtonItem { barButton.title = isSwitchingToUltraWide ? "Wide" : "Ultra Wide" barButton.tintColor = isSwitchingToUltraWide ? UIColor.systemGreen : UIColor.white } print("Switched to \(cameraName) camera.") } self.isUsingFisheyeCamera.toggle() } catch { DispatchQueue.main.async { self.showAlert(title: "Camera Error", message: "Failed to switch to \(cameraName) camera: \(error.localizedDescription)") } } } } Expected Behavior Torch should be able to work when Ultra-Wide is active, just like the iPhone Camera app does. The camera should not freeze when switching between Wide and Ultra-Wide with the torch ON. AVCaptureSession should not crash when toggling the torch while Ultra-Wide is active. Questions & Help Needed Is this a known issue with AVFoundation? How does the iPhone Camera app allow using the torch while recording in Ultra-Wide? What’s the correct way to switch between Wide and Ultra-Wide cameras without freezing when the torch is active? Info Device tested: iPhone 13 Pro / iPhone 15 Pro / Iphone 15 iOS Version: iOS 17.3 / iOS 18.0 Xcode Version: 16.2

I have an SCStreamDelegate for capturing frames from applications. On recent point releases of macOS Sonoma, I've noticed that the stream is being cancelled with no user action being taken. I started trying to debug it and when my on error method is called, the error parameter being passed is null: func stream(_ stream: SCStream, didStopWithError error: Error) { /*debugger shows this and segfaults if I try to print "\(error)" error (Error) > error = (Builtin.RawPointer) 0x0 */ From what I can tell, error should be a valid NSError so I can check the error code, based on similar code I've seen in, for example OBS (https://github.com/obsproject/obs-studio/blob/265239d4174f8d291b0de437088c5b78f8e27687/plugins/mac-capture/mac-sck-common.m#L29) Usually when this happens, the menubar icon for screen sharing (where I would click to change sharing window, etc) stays there even after my app has closed an no apps are doing sharing stuff. Has anyone come across this before? Am I misinterpreting what the debugger is saying about the error parameter? I'm running macos 14.7.3, but I just updated from 14.7.2 earlier and had basically the same issue on both macos versions

Hi, I have a problem when I want to attach my grayscale depth map image into the real image. The produced depth map doesn't have the cameraCalibration value which should responsible to align the depth data to the image. How do I align the depth map? I saw an article about it but it is not really detailed so I might be missing some process. I tried to: convert my depth map into pixel buffer create image destination ref and add the image there. add the auxData (depth map dict) This is the output: There is some black space there and my RGB image colour changes

I am developing an iOS application that supports screen mirroring to Google TV (or Chromecast with Google TV). My goal is to mirror the iPhone/iPad screen in real time to a Google TV device. What I Have Tried So Far I have explored multiple approaches but haven't found a direct way to achieve low-latency screen mirroring. Here are some of my findings: Google Cast SDK: Google Cast SDK is primarily designed for casting media (videos, images, audio) rather than real-time mirroring. It supports custom receiver applications, but there are no direct APIs for full screen mirroring. Casting a recorded video is possible, but it introduces latency and is not real-time. ReplayKit for Screen Capture: RPScreenRecorder.shared().startCapture(handler: ...) allows capturing the iPhone screen as a video stream. However, sending this stream to Google TV in real time is a challenge. I could potentially encode the video as HLS and stream it, but the delay is significant. RTSP/UDP Streaming: Some third-party libraries support RTSP/UDP streaming for real-time screen sharing. Google TV does not natively support RTSP, making this approach difficult. My Questions: Is it possible to achieve real-time screen mirroring on Google TV using Google Cast SDK? Does Google TV support WebRTC or any low-latency streaming protocol that can be used from iOS? Are there any alternative approaches to mirror an iOS screen to Google TV with minimal latency? I would appreciate any guidance, code examples, or references to relevant documentation.

Issue: Under certain conditions, using CallKit does not automatically enable the microphone. Steps to Reproduce: 1.Start an outgoing call, then the user manually mutes the audio. 2.Receive a native incoming call, end the current call, then answer the new incoming call.(This order is important.) 3.End the incoming call. 4.Start another outgoing call and observe the microphone; do not manually mute or unmute. Actual Behavior: The audio icon indicates that the audio is unmuted, but the microphone remains off, and the small yellow dot in the top status bar (which represents the microphone) does not appear. Expected Behavior: The microphone should be on, consistent with the audio icon display, and the small yellow dot should appear in the top status bar. Device: iPhone 16 pro & iPhone 15 pro, iOS 18.0+ Can it be reproduced using speakerbox(CallKit Demo)? YES

According to the docs: The first time your app performs an operation that requires [photo library] authorization, the system automatically and asynchronously prompts the user for it. (https://developer.apple.com/documentation/photokit/delivering-an-enhanced-privacy-experience-in-your-photos-app) I.e. it's not necessary for the app to call PHPhotoLibrary.requestAuthorization. This does seem to be what happens when my app runs on an iPhone or iPad; the prompt is shown. But when it runs on a Mac in "designed for iPad" mode, the permission dialog is not presented. Instead the code continues to see status == .notDetermined. That's today, on macOS 15.3. It may have worked in the past. Is anyone else seeing issues with this? Should I call requestAuthorization explicitly? (Would that actually work?)

Hello, I have a CarPlay Navigation app and utilize the AVSpeechSynthesizer to speak directions to a user. Everything works great on my CarPlay simulator as well as when plugged into my GMC truck. However, I found out yesterday that one of my users with a Ford truck the audio would cut in an out. After much troubleshooting, I was able to replicate this on my own truck when using Bluetooth to connect to CarPlay. My user was also utilizing Bluetooth. Has anyone else experienced this? Is there a fix to the problem? import SwiftUI import AVFoundation class TextToSpeechService: NSObject, ObservableObject, AVSpeechSynthesizerDelegate { private var speechSynthesizer = AVSpeechSynthesizer() static let shared = TextToSpeechService() override init() { super.init() speechSynthesizer.delegate = self } func configureAudioSession() { speechSynthesizer.delegate = self do { try AVAudioSession.sharedInstance().setCategory(.playback, mode: .voicePrompt, options: [.mixWithOthers, .allowBluetooth]) } catch { print("Failed to set audio session category: \(error.localizedDescription)") } } func speak(_ text: String) { Task(priority: .high) { let speechUtterance = AVSpeechUtterance(string: text) speechUtterance.voice = AVSpeechSynthesisVoice(language: AVSpeechSynthesisVoice.currentLanguageCode()) try AVAudioSession.sharedInstance().setActive(true, options: .notifyOthersOnDeactivation) speechSynthesizer.speak(speechUtterance) } } func speechSynthesizer(_ synthesizer: AVSpeechSynthesizer, didFinish utterance: AVSpeechUtterance) { Task { stopSpeech() try AVAudioSession.sharedInstance().setActive(false) } } func stopSpeech() { speechSynthesizer.stopSpeaking(at: .immediate) } }

We have application using PTT Framework to record audio messages when app is backgrounded. Right now we are using AVAudioRecorder for that purpose. And problem is one specific user has frequent issue - recorded audio contains only silence. I've checked almost everything I can imagine but didn't find any possible reason of issue. Conditions: AVAudioRecorder uses following configuration: [ AVEncoderAudioQualityKey: AVAudioQuality.low.rawValue, AVFormatIDKey : kAudioFormatMPEG4AAC, AVNumberOfChannelsKey: 1, AVSampleRateKey: 16000.0 ] App waits both didBeginTransmitting and didActivate audioSession from PTChannelManager (audio session has playback category at that moment) App does AVAudioSession category change to playAndRecord App gets routeChangeNotification with categoryChange and category = playAndRecord There is no any interruption notifications from AVAudioSession during recording There is no any error notification from AVAudioRecorder Any idea what exactly I do wrong? Is there anything else I should check? Thanks in advance. P.S. it looks like recording audio with AudioUnit has the same issue, but let's exclude it from question atm for simplicity.

I have created an app where you can speak using SFSpeechRecognizer and it will recognize you speech into text, translate it and then return it back using speech synthesis. All locales for SFSpeechRecognizer and switching between them work fine when the app is in the foreground but after I turn off my screen(the app is still running I just turned off the screen) and try to create new recognitionTask it it receives this error inside the recognition task: User denied access to speech recognition. The weird thing about this is it only happens with some languages. The error happens with Croatian or Hungarian locale for speech recognition but doesn't with English or Spanish locale.

I am creating an app that decodes H.265 elementary streams on iOS. I use VideoToolBox to decode from H.265 to NV12. The decoded data is enqueued in the CMSampleBufferDisplayLayer as a CMSampleBuffer. However, nothing is displayed in the VideoPlayerView. It remains black. The decoding in VideoToolBox is successful. I confirmed this by saving the NV12 data in the CMSampleBuffer to a file and displaying it using a tool. Why is nothing displayed in the VideoPlayerView? I can provide other source code as well. // // ContentView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI struct ContentView: View { var body: some View { VStack { Text("H.265 Player (temp.h265)") .font(.headline) VideoPlayerView() .frame(width: 360, height: 640) // Adjust or make it responsive for iOS } .padding() } } #Preview { ContentView() } // // VideoPlayerView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI import AVFoundation struct VideoPlayerView: UIViewRepresentable { // Return an H265Player as the coordinator, and start playback there. func makeCoordinator() -> H265Player { H265Player() } func makeUIView(context: Context) -> UIView { let uiView = UIView(frame: .zero) // Base layer for attaching sublayers uiView.backgroundColor = .black // Screen background color (for iOS) // Create the display layer and add it to uiView.layer let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.bounds displayLayer.backgroundColor = UIColor.clear.cgColor uiView.layer.addSublayer(displayLayer) // Start playback context.coordinator.startPlayback() return uiView } func updateUIView(_ uiView: UIView, context: Context) { // Reset the frame of the AVSampleBufferDisplayLayer when the view's size changes. let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.layer.bounds // Optionally update the layer's background color, etc. uiView.backgroundColor = .black displayLayer.backgroundColor = UIColor.clear.cgColor // Flush transactions if necessary CATransaction.flush() } } // // H265Player.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import Foundation import AVFoundation import CoreMedia class H265Player: NSObject, VideoDecoderDelegate { let displayLayer = AVSampleBufferDisplayLayer() private var decoder: H265Decoder? override init() { super.init() // Initial configuration for the display layer displayLayer.videoGravity = .resizeAspect // Initialize the decoder (delegate = self) decoder = H265Decoder(delegate: self) // For simple playback, set isBaseline to true decoder?.isBaseline = true } func startPlayback() { // Load the file "cars_320x240.h265" guard let url = Bundle.main.url(forResource: "temp2", withExtension: "h265") else { print("File not found") return } do { let data = try Data(contentsOf: url) // Set FPS and video size as needed let packet = VideoPacket(data: data, type: .h265, fps: 30, videoSize: CGSize(width: 1080, height: 1920)) // Decode as a single packet decoder?.decodeOnePacket(packet) } catch { print("Failed to load file: \(error)") } } // MARK: - VideoDecoderDelegate func decodeOutput(video: CMSampleBuffer) { // When decoding is complete, send the output to AVSampleBufferDisplayLayer displayLayer.enqueue(video) } func decodeOutput(error: DecodeError) { print("Decoding error: \(error)") } }

I set the device format and colorspace to Apple Log and turn off the HDR, why the movie output is still in HDR format rather than ProRes Log? Full runnable demo here: https://github.com/SpaceGrey/ColorSpaceDemo session.sessionPreset = .inputPriority // get the back camera let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: .video, position: .back) backCamera = deviceDiscoverySession.devices.first! try! backCamera.lockForConfiguration() backCamera.automaticallyAdjustsVideoHDREnabled = false backCamera.isVideoHDREnabled = false let formats = backCamera.formats let appleLogFormat = formats.first { format in format.supportedColorSpaces.contains(.appleLog) } print(appleLogFormat!.supportedColorSpaces.contains(.appleLog)) backCamera.activeFormat = appleLogFormat! backCamera.activeColorSpace = .appleLog print("colorspace is Apple Log \(backCamera.activeColorSpace == .appleLog)") backCamera.unlockForConfiguration() do { let input = try AVCaptureDeviceInput(device: backCamera) session.addInput(input) } catch { print(error.localizedDescription) } // add output output = AVCaptureMovieFileOutput() session.addOutput(output) let connection = output.connection(with: .video)! print( output.outputSettings(for: connection) ) /* ["AVVideoWidthKey": 1920, "AVVideoHeightKey": 1080, "AVVideoCodecKey": apch,<----- prores has enabled. "AVVideoCompressionPropertiesKey": { AverageBitRate = 220029696; ExpectedFrameRate = 30; PrepareEncodedSampleBuffersForPaddedWrites = 1; PrioritizeEncodingSpeedOverQuality = 0; RealTime = 1; }] */ previewSource = DefaultPreviewSource(session: session) queue.async { self.session.startRunning() } }

Hello! I'm use AVFoundation for preview video and audio from selected device, and I try use AVAudioEngine for preview audio in real-time, but I can't or I don't understand how select input device? I can hear only my microphone in real-time So far, I'm using AVCaptureAudioPreviewOutput for in real-time hear audio, but I think has delay. On iOS works easy with AVAudioEngine, but on macOS bruh...

Hello, Basically, I am reading and writing an asset. To simplify, I am just reading the asset and rewriting it into an output video without any modifications. However, I want to add a fade-out effect to the last three seconds of the output video. I don’t know how to do this. So far, before adding the CMSampleBuffer to the output video, I tried reducing its volume using an extension on CMSampleBuffer. In the extension, I passed 0.4 for testing, aiming to reduce the video's overall volume by 60%. My question is: How can I directly adjust the volume of a CMSampleBuffer? Here is the extension: extension CMSampleBuffer { func adjustVolume(by factor: Float) -> CMSampleBuffer? { guard let blockBuffer = CMSampleBufferGetDataBuffer(self) else { return nil } var length = 0 var dataPointer: UnsafeMutablePointer<Int8>? guard CMBlockBufferGetDataPointer(blockBuffer, atOffset: 0, lengthAtOffsetOut: nil, totalLengthOut: &length, dataPointerOut: &dataPointer) == kCMBlockBufferNoErr else { return nil } guard let dataPointer = dataPointer else { return nil } let sampleCount = length / MemoryLayout<Int16>.size dataPointer.withMemoryRebound(to: Int16.self, capacity: sampleCount) { pointer in for i in 0..<sampleCount { let sample = Float(pointer[i]) pointer[i] = Int16(sample * factor) } } return self } }

On an iOS 18 phone, I use AVCaptureSession to capture HDR with x420 format. The output CMSampleBuffer is HLG colorspace, the propagated attachments contain kCVImageBufferAmbientViewingEnvironmentKey and kCVImageBufferSceneIlluminationKey. Now I use CAMetalLayer to render the CVPixelBuffer to the screen, but the brightness is brighter than AVSampleBufferDisplayLayer. Here is my code. - (void)_updateColorSpaceIfNeed:(CVPixelBufferRef)pixelBuffer { CAMetalLayer *layer = (CAMetalLayer *)_mtkView.layer; if (![layer isKindOfClass:CAMetalLayer.class]) return; layer.wantsExtendedDynamicRangeContent = YES; CFDataRef ambientViewingEnvironment = (CFDataRef)CVBufferCopyAttachment(pixelBuffer, kCVImageBufferAmbientViewingEnvironmentKey, NULL); NSData *data = (__bridge NSData *)ambientViewingEnvironment; if (ambientViewingEnvironment) CFRelease(ambientViewingEnvironment); CAEDRMetadata *metadata = [CAEDRMetadata HLGMetadataWithAmbientViewingEnvironment:data]; // CAEDRMetadata *metadata = [CAEDRMetadata HLGMetadata]; layer.EDRMetadata = metadata; layer.pixelFormat = MTLPixelFormatRGBA16Float; CGColorSpaceRef colorspace = CGColorSpaceCreateWithName(kCGColorSpaceITUR_2100_HLG); layer.colorspace = colorspace; if (colorspace) CGColorSpaceRelease(colorspace); } Why does the CAEDRMetadata class have "HLGMetadataWithAmbientViewingEnvironment:" and "HLGMetadata" methods, but does not provide the "HLGMetadataWithAmbientViewingEnvironment:sceneIllumination" method? I want to know how kCVImageBufferAmbientViewingEnvironmentKey and kCVImageBufferSceneIlluminationKey affect tone mapping. Is there any documentation I can refer to?

Hello All, I am looking for assistance with our FairPlay Streaming (FPS) certificates. We are in the process of migrating to a new video streaming vendor and need to create a new FPS certificate using SDK 4. However, we have reached the limit of allowed FPS certificates in our account and cannot create a new one. Issue Details: • We currently have two FPS certificates active in our developer account. • One of these was created using SDK 5, but our new vendor (Mux) requires an FPS certificate based on SDK 4. • Since Apple does not allow deleting FPS certificates from the developer portal, we are unable to create a new SDK 4 certificate. • We kindly request Apple to revoke one of our existing FPS certificates to allow us to generate a new SDK 4 certificate. Request: We would greatly appreciate it if you could assist us on how to delete one of our existing FPS certificates so that we can proceed with creating a new SDK 4 certificate for our vendor integration. Thank you for your support.

When building an application that can be built on iOS using macCatalyst, a link error like the one below will occur. Undefined symbol: OBJC_CLASS$_AVPlayerViewController The AVPlayerViewController documentation seems to support macCatalyst, but what is the reality? [AVPlayerViewController](https://developer.apple.com/documentation/avkit/avplayerviewcontroller? language=objc) Each version of the environment is as follows. Xcode 16.2 macOS deployment target: macOS 10.15 iOS deployment target: iOS 13.0 Thank you for your support.

Bug Report: ScreenCaptureKit System Audio Capture Crashes with EXC_BAD_ACCESS Summary When using ScreenCaptureKit to capture system audio for extended periods, the application crashes with EXC_BAD_ACCESS in Swift's error handling runtime. The crash occurs in swift_getErrorValue when trying to process an error from the SCStream delegate method didStopWithError. This appears to be a framework-level issue in ScreenCaptureKit or its underlying ReplayKit implementation. Environment macOS Sonoma 14.6.1 Swift 5.8 ScreenCaptureKit framework Detailed Description Our application captures system audio using ScreenCaptureKit's audio capture capabilities. After successfully capturing for several minutes (typically after 3-4 segments of 60-second recordings), the application crashes with an EXC_BAD_ACCESS error. The crash happens when the Swift runtime attempts to process an error in the SCStreamDelegate.stream(_:didStopWithError:) method. The crash consistently occurs in swift_getErrorValue when attempting to access the class of what appears to be a null object. This suggests that the error being passed from the system framework to our delegate method is malformed or contains invalid memory. Steps to Reproduce Create an SCStream with audio capture enabled Add audio output to the stream Start capture and write audio data to disk Allow the capture to run for several minutes (3-5 minutes typically triggers the issue) The app will crash with EXC_BAD_ACCESS in swift_getErrorValue Code Sample func stream(_ stream: SCStream, didStopWithError error: Error) { print("Stream stopped with error: \(error)") // Crash occurs before this line executes } func stream(_ stream: SCStream, didOutputSampleBuffer sampleBuffer: CMSampleBuffer, of type: SCStreamOutputType) { guard type == .audio, sampleBuffer.isValid else { return } // Process audio data... } Expected Behavior The error should be properly propagated to the delegate method, allowing for graceful error handling and recovery. Actual Behavior The application crashes with EXC_BAD_ACCESS when the Swift runtime attempts to process the error in swift_getErrorValue. Crash Log Details Thread #35, queue = 'com.apple.NSXPCConnection.m-user.com.apple.replayd', stop reason = EXC_BAD_ACCESS (code=1, address=0x0) frame #0: 0x0000000194c3088c libswiftCore.dylib`swift::_swift_getClass(void const*) + 8 frame #1: 0x0000000194c30104 libswiftCore.dylib`swift_getErrorValue + 40 frame #2: 0x00000001057fba30 shadow`NewScreenCaptureService.stream(stream=0x0000600002de6700, error=Swift.Error @ 0x000000016b7b5e30) at NEW+ScreenCaptureService.swift:365:15 frame #3: 0x00000001057fc050 shadow`@objc NewScreenCaptureService.stream(_:didStopWithError:) at <compiler-generated>:0 frame #4: 0x0000000219ec5ca0 ScreenCaptureKit`-[SCStreamManager stream:didStopWithError:] + 456 frame #5: 0x00000001ca68a5cc ReplayKit`-[RPScreenRecorder stream:didStopWithError:] + 84 frame #6: 0x00000001ca696ff8 ReplayKit`-[RPDaemonProxy stream:didStopWithError:] + 224 Printing description of stream._streamQueue: error: ObjectiveC.id:4294967281:18: note: 'id' has been explicitly marked unavailable here public typealias id = AnyObject ^ error: /var/folders/v4/3xg1hmp93gjd8_xlzmryf_wm0000gn/T/expr23-dfa421..cpp:1:65: 'id' is unavailable in Swift: 'id' is not available in Swift; use 'Any' Swift._DebuggerSupport.stringForPrintObject(Swift.UnsafePointer<id>(bitPattern: 0x104ae08c0)!.pointee) ^~ ObjectiveC.id:2:18: note: 'id' has been explicitly marked unavailable here public typealias id = AnyObject ^ warning: /var/folders/v4/3xg1hmp93gjd8_xlzmryf_wm0000gn/T/expr23-dfa421..cpp:5:7: initialization of variable '$__lldb_error_result' was never used; consider replacing with assignment to '_' or removing it var $__lldb_error_result = __lldb_tmp_error ~~~~^~~~~~~~~~~~~~~~~~~~ _ Before the crash, we observed this error message in the console: [ERROR] *****SCStream*****RemoteAudioQueueOperationHandlerWithError:1015 Error received from the remote queue -16665 Additional Context The issue occurs consistently after approximately 3-4 successful audio segment recordings of 60 seconds each Commenting out custom segment rotation logic does not prevent the crash The crash involves XPC communication with Apple's ReplayKit daemon The error appears to be corrupted or malformed when crossing the XPC boundary Workarounds Attempted Added proper thread safety for all published properties using DispatchQueue.main.async Implemented more robust error handling in the delegate methods None of these approaches prevented the crash since it occurs at the Swift runtime level before our code executes. Impact This issue prevents reliable long-duration audio capture using ScreenCaptureKit. This bug significantly limits the usefulness of ScreenCaptureKit for any application requiring continuous system audio capture for more than a few minutes. Perhaps this issue might be related to a macOS bug where the system dialog indicates that the screen is being shared, even though nothing is actually being shared. Moreover, when attempting to stop sharing, nothing happens.

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.