Hi All, I am working on a DJ playout app (MACOS). The app has a few AVAudioPlayerNode's combined with the ApplicationMusicPlayer from Musickit. I can route the output of the AVaudioPlayer to a hardware device so that the audio files are directed to their own dedicated output on my Mac. The ApplicationMusicPlayer is following the default output and this is pretty annoying. Has anyone found a solution to chain the ApplicationMusicPlayer and get it set to a output device? Thanks Pancras

Our multimedia application Boinx FotoMagico displays media files of various kinds with a Metal rendering engine. At the moment we still use .bgra8Unorm pixel format and sRGB color space and only render in SDR, which is increasingly a problem, as much of the video content is HDR nowadays (e.g. videos shot on an iPhone). For that reason we would like to switch to EDR rendering with .rgba16Float pixel format and extendedLinearDisplayP3 color space. We have already worked out how to do this for HDR image files, but still have a technical problem when rendering HDR video files. We are using AVFoundation to get the video frames as CVPixelBuffers and convert them to MTLTexture using a CVMetalTextureCache. MTLTextures are then further processed in various compute shaders before being rendered to screen. However the pixel values in the texture are not what we expected. Video frames appear too bright/overexposed. In WWDC21 session "Explore HDR rendering with EDR" Ken Greenebaum mentioned: “AVFoundation does not presently decode HDR formats, such as HDR10, to EDR. Consequently, these need to be adapted for use with EDR rendering. This conversion is straightforward and involves two steps. First, converting to linear light by applying the inverse transfer function. And second, dividing by the medium's reference white.” https://developer.apple.com/videos/play/wwdc2021/10161?time=1498 However, the session does not explain, how to get or calculate the correct value for "reference white". We could not find any relevant info on the web. This is why we need DTS assistance. We need the code that calculates the correct value for reference white for any kind of video, whether it is SDR or HDR, and regardless of codec and encoding. I assume that Ken Greenebaum is the best Apple engineer to ask in this case, because he recorded most of the EDR related WWDC sessions in recent years? We have written a small test app that renders a short sample video (HLG encoding). The window contains two views. The upper view uses an AVPlayerLayer and renders the video natively just like QuickTime Player. The video content looks correct here. BTW, the window background is SDR white, so that bright EDR pixels can be clearly identified, e.g. the clouds just above the mountains in the upper left corner of the sample video. You may need to lower display brightness a bit if these clouds do not appear brighter than the white window background. The bottom view uses a CAMetalLayer and low-level Metal rendering. The CVPixelBuffers we receive from AVFoundation still need to be scaled down so that SDR reference white reaches pixel value 1.0. Entering a value of 9.0 to 10.0 for reference white in the text field makes it look about right on my Studio Display. But that is just experimental for this sample video file. We need code to calculate the correct value for reference white for any kind of video file! We have a couple of questions: SDR videos should probably use 1.0 as reference white, as their encoded pixel values can already be used as is? Is this assumption correct? Different video encoding of HDR video (HLG, PQ, etc) will probably lead to different values for reference white? Is the value for reference white constant throughout a video, or can it vary over time, either scene by scene, or even frame by frame? If it can vary, does the CVPixelBuffer of the current video frame contain all the necessary metadata to calculate the correct value? Does the NSScreen.maximumExtendedDynamicRangeColorComponentValue also influence the reference white value? The attached sample project is structured in a way that the only piece of code that needs to be modified is the ViewController.sdrReferenceWhiteValue() function. Please read the comments and the #warning in this function. This is where the code for calculating the reference white value should be inserted. Here is the download link for the sample project: https://www.dropbox.com/scl/fi/4w5gmftav5xhbixu9u6pb/HDRMetalTest.zip?rlkey=n8cm02soux3rx03vplgo6h1lm&dl=0

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) } }

Hi, just generated a HDR10 MVHEVC file, mediainfo is below: Color range : Limited Color primaries : BT.2020 Transfer characteristics : PQ Matrix coefficients : BT.2020 non-constant Codec configuration box : hvcC+lhvC then generate the segment files with below command: mediafilesegmenter --iso-fragmented -t 4 -f av_1 av_new_1.mov then upload the segment files and prog_index.m3u8 to web server. just find that can not play the HLS stream on Safari... the url is http://ip/vod/prog_index.m3u8 just checked that if i remove the tag Transfer characteristics : PQ when generating the MVHEVC file. above same mediafilesegmenter command and upload the files to web server. the new version of HLS stream is can play on Safari... Is there any way to play HLS PQ video on Safari. thanks.

I have an HDR10+ encoded video that if loaded as a mov plays back on the Apple Vision Pro but when that video is encoded using the latest (1.23b) Apple HLS tools to generate an fMP4 - the resulting m3u8 cannot be played back in the Apple Vision Pro and I only get back a "Cannot Open" error. To generate the m3u8, I'm just calling mediafilesegmenter (with -iso-fragmented) and then variantplaylistcreator. This completes with no errors but the m3u8 will playback on the Mac using VLC but not on the Apple Vision Pro. The relevant part of the m3u8 is: #EXT-X-STREAM-INF:AVERAGE-BANDWIDTH=40022507,BANDWIDTH=48883974,VIDEO-RANGE=PQ,CODECS="ec-3,hvc1.1.60000000.L180.B0",RESOLUTION=4096x4096,FRAME-RATE=24.000,CLOSED-CAPTIONS=NONE,AUDIO="audio1",REQ-VIDEO-LAYOUT="CH-STEREO" {{url}} Has anyone been able to use the HLS tools to generate fMP4s of MV-HEVC videos with HDR10?

I am would like to look at AVMetricEvent data during video playback, so I have added this code to a test video player app: let playerItem: AVPlayerItem = ... let allMetrics = playerItem.allMetrics() Task.init { print("metrics task started") do { for try await metricEvent in allMetrics { print("metric event: \(metricEvent.description)") } } catch { print("unexpected metric iterator error \(error)") } } Running this in Simulator on iPhone 16 Pro (18.0) does not result in any "metric event" diagnostic messages being printed when the video associated with this AVPlayerItem is playing. Only the "metric task started" diagnostic message is seen. What am I doing wrong that prevents metric data being received?

Please include the line below in follow-up emails for this request. Case-ID: 11089799 When using AVSpeechUtterance and setting it to play in Mandarin, if Siri is set to Cantonese on iOS 18, it will be played in Cantonese. There is no such issue on iOS 17 and 16. 1.let utterance = AVSpeechUtterance(string: textView.text) let voice = AVSpeechSynthesisVoice(language: "zh-CN") utterance.voice = voice 2.In the phone settings, Siri is set to Cantonese

I would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model.

I am new here and would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model. I am able to create from LiDAR scanning 3D mesh and .OBJ file but can not generate .MTL and .JPEG for a texture of 3D model.

We are encountering a critical, intermittently occurring crash issue when accessing photo data using PHAssetResourceManager.writeDataForAssetResource on iOS 18. The problem does not arise on iOS 17 or earlier versions. We have been unable to identify a consistent reproduction path. Based on user feedback, the issue seems to involve Live Photo and Raw image files. Our investigation has revealed that the crash occurs in the +[PISchema identifier] method of the PhotoImaging Framework. When called manually, this method causes a crash on iOS 18 but works without issues on iOS 17. Reproduction Steps: 1.Fetch PHAsset. 2.Get PHAssetResource by [PHAssetResource assetResourcesForAsset:]. 3.Call [PHAssetResourceManager writeDataForAssetResource:toFile:options:completionHandler:]. Crash Log: Incident Identifier: CFD60092-FDB1-43B4-BA42-3F507F7B8B96 CrashReporter Key: 260b4780989083a54e0cb451930fe9a3bed64862 Hardware Model: iPhone13,4 AppStoreTools: 16C5031b AppVariant: 1:iPhone13,4:18 Code Type: ARM-64 (Native) Role: Foreground Parent Process: launchd [1] Date/Time: 2025-02-15 19:07:57.7054 +0800 Launch Time: 2025-02-15 19:07:55.4106 +0800 OS Version: iPhone OS 18.3.1 (22D72) Release Type: User Baseband Version: 5.20.03 Report Version: 104 Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Termination Reason: SIGNAL 6 Abort trap: 6 Terminating Process: mCloud_iPhone [11109] Triggered by Thread: 11 Application Specific Information: abort() called Thread 11 name: Dispatch queue: com.apple.NSXPCConnection.m-user.com.apple.photos.service Thread 11 Crashed: 0 libsystem_kernel.dylib 0x1e850b2d4 __pthread_kill + 8 1 libsystem_pthread.dylib 0x221b4959c pthread_kill + 268 2 libsystem_c.dylib 0x19ec24b08 abort + 128 3 NeutrinoCore 0x1bdcdbdec -[NUAssertionPolicyAbort notifyAssertion:] + 68 4 NeutrinoCore 0x1bdcdbbf4 -[NUAssertionPolicyComposite notifyAssertion:] + 160 5 NeutrinoCore 0x1bdcdc098 -[NUAssertionPolicyUnique notifyAssertion:] + 176 6 NeutrinoCore 0x1bdcdb524 -[NUAssertionHandler handleFailureInFunction:file:lineNumber:currentlyExecutingJobName:description:arguments:] + 156 7 NeutrinoCore 0x1bdcdc4bc _NUAssertFailHandler + 176 8 NeutrinoCore 0x1bdc8ea98 -[NUIdentifier initWithNamespace:name:version:] + 2352 9 NeutrinoCore 0x1bdc8eba8 -[NUIdentifier initWithName:version:] + 84 10 NeutrinoCore 0x1bdc8ec10 -[NUIdentifier initWithName:] + 68 11 PhotoImaging 0x1bda54ce4 +[PISchema identifier] + 36 12 PhotoImaging 0x1bda550fc +[PISchema registeredPhotosSchemaIdentifier] + 32 13 PhotoImaging 0x1bd9d7128 +[PIPhotoEditHelper newComposition] + 28 14 PhotoImaging 0x1bd940798 +[PICompositionSerializer deserializeCompositionFromAdjustments:metadata:formatIdentifier:formatVersion:sidecarData:error:] + 160 15 PhotoImaging 0x1bd9412ec +[PICompositionSerializer deserializeCompositionFromData:formatIdentifier:formatVersion:sidecarData:error:] + 224 16 PhotoLibraryServices 0x1afabf75c -[PLPhotoEditPersistenceManager loadCompositionFrom:formatIdentifier:formatVersion:sidecarData:error:] + 1856 17 PhotoLibraryServices 0x1afabffe4 +[PLPhotoEditPersistenceManager validateAdjustmentData:formatIdentifier:formatVersion:error:] + 108 18 Photos 0x1af4ac360 __167+[PHContentEditingInputRequestContext contentEditingInputRequestContextForAsset:requestID:managerID:networkAccessAllowed:downloadIntent:progressHandler:resultHandler:]_block_invoke + 260 19 Photos 0x1af4ac67c -[PHAdjustmentData(ContentEditingInput) _contentEditing_readableByClientWithVerificationBlock:] + 136 20 Photos 0x1af4ac4b0 -[PHAdjustmentData(ContentEditingInput) _contentEditing_requiredBaseVersionReadableByClient:verificationBlock:] + 88 21 Photos 0x1af4abb8c -[PHContentEditingInputRequestContext _adjustmentBaseVersionFromResult:request:canHandleAdjustmentData:] + 404 22 Photos 0x1af4a911c -[PHContentEditingInputRequestContext produceChildRequestsForRequest:reportingIsLocallyAvailable:isDegraded:result:] + 624 23 Photos 0x1af2c1d10 -[PHMediaRequestContext _produceChildRequestsForRequest:withResult:] + 88 24 Photos 0x1af2c11e8 -[PHMediaRequestContext mediaRequest:didFinishWithResult:] + 88 25 Photos 0x1af505184 -[PHAdjustmentDataRequest _finishFromAsynchronousCallback] + 124 26 Photos 0x1af5050a0 __39-[PHAdjustmentDataRequest startRequest]_block_invoke + 584 27 PhotoLibraryServicesCore 0x1b001be8c __106-[PLAssetsdResourceClient adjustmentDataForAsset:networkAccessAllowed:trackCPLDownload:completionHandler:]_block_invoke.86 + 864 28 CoreFoundation 0x196dd8e34 __invoking___ + 148 29 CoreFoundation 0x196dd7e7c -[NSInvocation invoke] + 428 30 Foundation 0x195a64ae0 __NSXPCCONNECTION_IS_CALLING_OUT_TO_EXPORTED_OBJECT__ + 16 31 Foundation 0x195a63514 -[NSXPCConnection _decodeAndInvokeReplyBlockWithEvent:sequence:replyInfo:] + 532 32 Foundation 0x195a6653c __88-[NSXPCConnection _sendInvocation:orArguments:count:methodSignature:selector:withProxy:]_block_invoke_5 + 188 33 libxpc.dylib 0x221babb80 _xpc_connection_reply_callout + 116 34 libxpc.dylib 0x221b9e2d0 _xpc_connection_call_reply_async + 80 35 libdispatch.dylib 0x19eb6b028 _dispatch_client_callout3 + 20 36 libdispatch.dylib 0x19eb88b64 _dispatch_mach_msg_async_reply_invoke + 340 37 libdispatch.dylib 0x19eb7242c _dispatch_lane_serial_drain + 352 38 libdispatch.dylib 0x19eb73158 _dispatch_lane_invoke + 432 39 libdispatch.dylib 0x19eb7e38c _dispatch_root_queue_drain_deferred_wlh + 288 40 libdispatch.dylib 0x19eb7dbd8 _dispatch_workloop_worker_thread + 540 41 libsystem_pthread.dylib 0x221b44680 _pthread_wqthread + 288 42 libsystem_pthread.dylib 0x221b42474 start_wqthread + 8

Our team conducted security testing and found one vulnerability with fairplay license acquisition. Our QA engineer manually changed the device's system date and time (setting it 4 days into the future) and was able to successfully obtain a license response and initiate playback on an iOS device. However, on an Android device, the license acquisition failed. Can you please tell us if Time Manipulation Detection is available in FairPlay SDK?

Hello, Apple video engineers. According to the official documentation, HLS is built on HTTP and traditionally ran on top of TCP. However, with the introduction of HTTP/3, which uses QUIC (runs on top of UDP), I would like to clarify the following: Has the official HLS specification changed in a way that allows it to be considered UDP-based when using HTTP/3? And is it fair to say that HLS supports UDP since the transport can go over HTTP/3 and QUIC? Would it be more accurate to say that HLS remains HTTP-dependent, and the transport protocol (TCP or QUIC) only determines how HTTP requests are delivered? My thoughts: Since HTTP/3 uses QUIC running over UDP, we still can't say that HLS supports UDP in a classical way, as it is introduced in RTP, RTSP, SRT.

I am trying to recreate the iOS Messages app photo selection UI, where a PHPickerViewController is displayed half screen, with the message text field and a scrolling photo viewer on top. I have that UI mostly working, but cannot figure out how to allow a user to remove an image from my scrolling photo viewer (just like in the iOS Messages app). When the picker is initially displayed, I can show selected images using the preselectedAssetIdentifiers. However, if the user taps the "x" to remove an image from the scrolling photo viewer, there is no way that I have found to update that selection in the picker. I can dismiss/show a new picker with the animated property set to false, but that creates a very apparent bounce in the screen. Are there any ways I am missing to accomplish this? Here is what I have so far:

Hi, I'm working on an audio mixing app, that comes with bundled audio units that provide some of the app's core functionality. For the next release of that app, we are planning to make two changes: make the app sandboxed package the bundled audio units as .appex bundles instead as .component bundles, so we don't need to take care of the installation at the correct spot in the file system When trying this new approach, we run into problems where [[AVAudioUnitEffect alloc] initWithAudioComponentDescription:] crashes when trying to load our audio unit with the exception: AVAEInternal.h:109 [AUInterface.mm:468:AUInterfaceBaseV3: (AudioComponentInstanceNew(comp, &_auv2)): error -10863 Our audio unit has the `sandboxSafe flag enabled, and loads fine when the host app is not sandboxed, so I'm guessing I got the bundle id/code signing requirements for the .appex correct. It seems, that my .appex isn't even loaded, and the system rejects it because of its metadata. Maybe there something wrong the Info.plist generated by Juice? "BuildMachineOSBuild" => "23H222" "CFBundleDisplayName" => "elgato_sample_recorder" "CFBundleExecutable" => "ElgatoSampleRecorder" "CFBundleIdentifier" => "com.iwascoding.EffectLoader.samplerecorderAUv3" "CFBundleName" => "elgato_sample_recorder" "CFBundlePackageType" => "XPC!" "CFBundleShortVersionString" => "1.0.0.0" "CFBundleSignature" => "????" "CFBundleSupportedPlatforms" => [ 0 => "MacOSX" ] "CFBundleVersion" => "1.0.0.0" "DTCompiler" => "com.apple.compilers.llvm.clang.1_0" "DTPlatformBuild" => "24C94" "DTPlatformName" => "macosx" "DTPlatformVersion" => "15.2" "DTSDKBuild" => "24C94" "DTSDKName" => "macosx15.2" "DTXcode" => "1620" "DTXcodeBuild" => "16C5032a" "LSMinimumSystemVersion" => "10.13" "NSExtension" => { "NSExtensionAttributes" => { "AudioComponents" => [ 0 => { "description" => "Elgato Sample Recorder" "factoryFunction" => "elgato_sample_recorderAUFactoryAUv3" "manufacturer" => "Manu" "name" => "Elgato: Elgato Sample Recorder" "sandboxSafe" => 1 "subtype" => "Znyk" "tags" => [ 0 => "Effects" ] "type" => "aufx" "version" => 65536 } ] } "NSExtensionPointIdentifier" => "com.apple.AudioUnit-UI" "NSExtensionPrincipalClass" => "elgato_sample_recorderAUFactoryAUv3" } "NSHighResolutionCapable" => 1 } Any ideas what I am missing?

Hello, my company is developing a product that will send data to/from the phone over cable and Wi-Fi. I have three questions: Do we need an MFi authentication chip in our product if we plan to send video and commands to the iPhone/iPad over USB or Lightning cable? Likewise, do we need an MFI authentication chip for communication over Wi-Fi? (Informal research suggests that the answer is no to this one.) And, do we even still need MFI certification at all for Wi-Fi comms? (We are not using HomeKit.) Thank you!

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. // // 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)") } }

We are planning to develop an application using the Apple Music API. We would like to design our system based on the details of the rate limits mentioned below and have a few questions: https://developer.apple.com/documentation/applemusicapi/generating-developer-tokens#Request-Rate-Limiting Regarding the Catalog API (/v1/catalog/*), we understand that server-side caching is enabled, making it less likely to reach the rate limit. Is this understanding correct? (Excluding the search API) For APIs like the Library API (/v1/me/library/*), where responses vary by user, we assume they are more likely to reach the rate limit. Is this correct? We plan to implement optimizations to minimize unnecessary API calls. Given this, would the current Music API be able to handle a significant increase in users? (Assuming a DAU of around 100,000 to 1,000,000) If the API cannot support this scale, would it be allowed under Apple’s policy to cache responses from the Catalog API (/v1/catalog/*) via our proxy server to avoid hitting the rate limit? The third question is the one we most want to confirm.

When setting the now playing info for playing media in MPNowPlayingInfoCenter we can set artwork. But it seems the Apple API for creating the artwork is crashing on iOS 18 (FB15145734). On iOS 17 this gave the warning that the completion handler was not run on the main thread. I've tried to seek help here: https://stackoverflow.com/questions/78989543/swift-data-race-with-appkit-mpmediaitemartwork-function/78990231?noredirect=1#comment139277425_78990231 but it seems that it's not possible to override the completion handler and therefor it's up to Apple to fix this issue. .task { await MainActor.run { let nowPlayingInfoCenter = MPNowPlayingInfoCenter.default() var nowPlayingInfo = [String: Any]() let image = NSImage(named: "image")! // warning: data race detected: @MainActor function at MPMediaItemArtwork/ContentView.swift:22 was not called on the main thread nowPlayingInfo[MPMediaItemPropertyArtwork] = MPMediaItemArtwork(boundsSize: image.size, requestHandler: { _ in // Not on main thread here! return image }) nowPlayingInfoCenter.nowPlayingInfo = nowPlayingInfo } } I'm wondering if there is an alternative method to set the now playing artwork?

I want to modify the photo's exif information, which means putting the original image in through CGImageDestinationAddImageFromSource, and then adding the modified exif information to a place called properties. Here is the complete process: static func setImageMetadata(asset: PHAsset, exif: [String: Any]) { let options = PHContentEditingInputRequestOptions() options.canHandleAdjustmentData = { (adjustmentData) -> Bool in return true } asset.requestContentEditingInput(with: options, completionHandler: { input, map in guard let inputNN = input else { return } guard let url = inputNN.fullSizeImageURL else { return } let output = PHContentEditingOutput(contentEditingInput: inputNN) let adjustmentData = PHAdjustmentData(formatIdentifier: AppInfo.appBundleId(), formatVersion: AppInfo.appVersion(), data: Data()) output.adjustmentData = adjustmentData let outputURL = output.renderedContentURL guard let source = CGImageSourceCreateWithURL(url as CFURL, nil) else { return } guard let dest = CGImageDestinationCreateWithURL(outputURL as CFURL, UTType.jpeg.identifier as CFString, 1, nil) else { return } CGImageDestinationAddImageFromSource(dest, source, 0, exif as CFDictionary) let d = CGImageDestinationFinalize(dest) // d is true, and I checked the content of outputURL, image has been write correctly, it could be convert to UIImage and image is ok. PHPhotoLibrary.shared().performChanges { let changeReq = PHAssetChangeRequest(for: asset) changeReq.contentEditingOutput = output } completionHandler: { succ, err in if !succ { print(err) // 3303 here, always! } } }) }

It's only occurs on iOS 18+. Backtrace attached below. Exception Codes: 0x0000000000000000, 0x0000000000000000 Termination Reason: SIGNAL 6 Abort trap: 6 Terminating Process: NoteKeys [24384] Triggered by Thread: 0 Last Exception Backtrace: 0 CoreFoundation 0x1a2d4c7cc __exceptionPreprocess + 164 (NSException.m:249) 1 libobjc.A.dylib 0x1a001f2e4 objc_exception_throw + 88 (objc-exception.mm:356) 2 CoreFoundation 0x1a2e47748 +[NSException raise:format:] + 128 (NSException.m:0) 3 AVFAudio 0x1bd41f4c8 -[AVMIDIPlayer play:] + 300 (AVMIDIPlayer.mm:145) 4 NoteKeys 0x1023c0670 SoundGenerator.playData() + 20 (SoundGenerator.swift:170) 5 NoteKeys 0x1023c0670 EditViewController.playBtnTapped(startIndex:) + 940 (EditViewController.swift:2034) 6 NoteKeys 0x1024497fc specialized Keyboard.playBtnTapped(sender:) + 1904 (Keyboard.swift:1249) 7 NoteKeys 0x10244631c Keyboard.playBtnTapped(sender:) + 4 (<compiler-generated>:0) 8 NoteKeys 0x10244631c @objc Keyboard.playBtnTapped(sender:) + 48 9 UIKitCore 0x1a58739cc -[UIApplication sendAction:to:from:forEvent:] + 100 (UIApplication.m:5816) 10 UIKitCore 0x1a58738a4 -[UIControl sendAction:to:forEvent:] + 112 (UIControl.m:942) 11 UIKitCore 0x1a58736f4 -[UIControl _sendActionsForEvents:withEvent:] + 324 (UIControl.m:1013) 12 UIKitCore 0x1a5fe8d8c -[UIButton _sendActionsForEvents:withEvent:] + 124 (UIButton.m:4198) 13 UIKitCore 0x1a5fea5a0 -[UIControl touchesEnded:withEvent:] + 400 (UIControl.m:692) 14 UIKitCore 0x1a57bb9ac -[UIWindow _sendTouchesForEvent:] + 852 (UIWindow.m:3318) 15 UIKitCore 0x1a57bb3d8 -[UIWindow sendEvent:] + 2964 (UIWindow.m:3641) 16 UIKitCore 0x1a564fb70 -[UIApplication sendEvent:] + 376 (UIApplication.m:12972) 17 UIKitCore 0x1a565009c __dispatchPreprocessedEventFromEventQueue + 1048 (UIEventDispatcher.m:2686) 18 UIKitCore 0x1a5659f3c __processEventQueue + 5696 (UIEventDispatcher.m:3044) 19 UIKitCore 0x1a5552c60 updateCycleEntry + 160 (UIEventDispatcher.m:133) 20 UIKitCore 0x1a55509d8 _UIUpdateSequenceRun + 84 (_UIUpdateSequence.mm:136) 21 UIKitCore 0x1a5550628 schedulerStepScheduledMainSection + 172 (_UIUpdateScheduler.m:1171) 22 UIKitCore 0x1a555159c runloopSourceCallback + 92 (_UIUpdateScheduler.m:1334) 23 CoreFoundation 0x1a2d20328 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28 (CFRunLoop.c:1970) 24 CoreFoundation 0x1a2d202bc __CFRunLoopDoSource0 + 176 (CFRunLoop.c:2014) 25 CoreFoundation 0x1a2d1ddc0 __CFRunLoopDoSources0 + 244 (CFRunLoop.c:2051) 26 CoreFoundation 0x1a2d1cfbc __CFRunLoopRun + 840 (CFRunLoop.c:2969) 27 CoreFoundation 0x1a2d1c830 CFRunLoopRunSpecific + 588 (CFRunLoop.c:3434) 28 GraphicsServices 0x1eecfc1c4 GSEventRunModal + 164 (GSEvent.c:2196) 29 UIKitCore 0x1a5882eb0 -[UIApplication _run] + 816 (UIApplication.m:3844) 30 UIKitCore 0x1a59315b4 UIApplicationMain + 340 (UIApplication.m:5496) 31 NoteKeys 0x10254bc10 main + 68 (AppDelegate.swift:15) 32 dyld 0x1c870aec8 start + 2724 (dyldMain.cpp:1334) Thanks very much for any help: )