I’m building a professional camera app where users can customize the video recording format and color grading. In the func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) method, I handle video frames and use Metal for real-time color grading. This works well when device.activeColorSpace is sRGB or P3, and the results are great. However, when the color space is HLG_BT2020 or appleLog, the MTKTextureLoader.newTexture(cgImage: cgImage, options: options) method throws an error. After researching, I found that the video frame in these color spaces has a bit-per-channel (bpc) greater than 8 after being converted to CGImage, causing the texture creation to fail. I tried converting the CGImage to a lower bpc to successfully create the texture, but the final output image is garbled and not as expected. Is there a solution to this issue?

I am seeing a crash on iOS 18.0 in my app due to PHImageManager.default().requestImage. Same crash is seen even while using requestImageDataAndOrientation. Not sure why this is happening only on iOS 18.0. Any help on this would be appreciated. Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000010 Exception Codes: 0x0000000000000001, 0x0000000000000010 VM Region Info: 0x10 is not in any region. Bytes before following region: 4310777840 REGION TYPE START - END [ VSIZE] PRT/MAX SHRMOD REGION DETAIL UNUSED SPACE AT START ---> Termination Reason: SIGNAL 11 Segmentation fault: 11 Terminating Process: exc handler [695] Triggered by Thread: 14 Thread 14 name: Dispatch queue: */file=33) .Generic Thread 14 Crashed: 0 libobjc.A.dylib 0x1944d7020 objc_msgSend + 32 1 PhotoLibraryServices 0x1b080262c +[PLUniformTypeIdentifier utiWithCompactRepresentation:conformanceHint:] + 40 2 Photos 0x1b0081354 _resourceInfoFromResultDict + 1048 3 Photos 0x1b0080a7c fetchResourcesForChoosing + 584 4 Photos 0x1b0080714 ___fetchNonHintResources_block_invoke.227 + 152 5 PhotoLibraryServices 0x1b026b3c4 __53-[PLManagedObjectContext _directPerformBlockAndWait:]_block_invoke + 48 6 CoreData 0x19f171b00 developerSubmittedBlockToNSManagedObjectContextPerform + 228 7 libdispatch.dylib 0x19eeff584 _dispatch_client_callout + 16 8 libdispatch.dylib 0x19eef5728 _dispatch_lane_barrier_sync_invoke_and_complete + 56 9 CoreData 0x19f1c2a0c -[NSManagedObjectContext performBlockAndWait:] + 308 10 PhotoLibraryServices 0x1b026cea4 -[PLManagedObjectContext _directPerformBlockAndWait:] + 144 11 PhotoLibraryServices 0x1b026cdf8 -[PLManagedObjectContext performBlockAndWait:] + 196 12 Photos 0x1b00804a4 _fetchNonHintResources + 292 13 Photos 0x1afeedb38 PHChooserListContinueEnumerating + 144 14 Photos 0x1afeed9f8 -[PHImageResourceChooser presentNextQualifyingResource] + 412 15 Photos 0x1afeed1d0 -[PHImageRequest startRequest] + 2424 16 libdispatch.dylib 0x19eee5aac _dispatch_call_block_and_release + 32 17 libdispatch.dylib 0x19eeff584 _dispatch_client_callout + 16 18 libdispatch.dylib 0x19eeee2d0 _dispatch_lane_serial_drain + 740 19 libdispatch.dylib 0x19eeeede0 _dispatch_lane_invoke + 440 20 libdispatch.dylib 0x19eef91dc _dispatch_root_queue_drain_deferred_wlh + 292 21 libdispatch.dylib 0x19eef8a60 _dispatch_workloop_worker_thread + 540 22 libsystem_pthread.dylib 0x2214d5660 _pthread_wqthread + 292 23 libsystem_pthread.dylib 0x2214d29f8 start_wqthread + 8

Hi! I am writing a browser extension that allows you to control the playback of media content on a music service website. Unfortunately Safari does not support tracking changes to the audible property in an event tabs.onUpdated. Is there an alternative to this event? I'm looking for a way to track when the automatic inference engine interrupts playback on a music service website. That you.

Hi, Could anybody share the full list of supported Predicate keys for the PHFetchOptions? I'm aware of the list that is posted in the documentation: https://developer.apple.com/documentation/photos/phfetchoptions However I have reason to believe that this is not an exhaustive list and there also seem to be mistakes in this doc. i.e. isFavorite does not work but favorite does. Through some experimentation I also found that this works: NSPredicate(format: "adjustmentFormatIdentifier == 'com.pixelmatorteam.touch.x.photo.PhotosAdjustmentData.EmbeddedSlimSidecarFileInfo.compressed'") even though adjustmentFormatIdentifier is not listed as a supported key. Are there other secret keys that you are aware of? Specifically I want to filter a fetch result for edited items. Something like this: NSPredicate(format: "hasAdjustments == true") (I tried this, doesn't work) The native Photos app has such a filter which leads me to believe that there probably is a key for this: If one of the Framework Developers reads this: Could you please update the documentation page with this information? Finally if there really aren't any more secret keys, is there a way to achieve this with adjustmentFormatIdentifier? I have tried a bunch of stuff already like adjustmentFormatIdentifier != nil but for some reason that gives me the exact opposite of what I want: all the photos without edits. 🫠 Any tips on the correct syntax here would be much appreciated.

We are currently working on a CarPlay navigation app and so far everything is working well except for speaking turn notifications. Our TTS implementation works fine on the phone and works fine on CarPlay if the voice is spoken over the speaker in the car. If users connect a BT headset to the car and listen through that headset, then the voice commands are chopped up / stutter. Why would users use BT headset? Well, we are working on a motorcycle app, and there are no speakers usually on a motorcycle. It sounds like the BT channel is opened and closed repeatedly for every character / word spoken. This happens on different CarPlay devices and different Bluetooth headsets, we have reports from multiple users that they find this behavior annoying and that other apps work fine. Is this a known issue? Are there possible workaround?

When using the Apple Devices to sync Apple Music to iPhone where is the Apple Devices backup being written to? Apple Devices->music->sync. Not trying to backup the iPhone via Apple Devices app.

We're experiencing significant issues with AVPlayer when attempting to play partially downloaded HLS content in offline mode. Our app downloads HLS video content for offline viewing, but users encounter the following problems: Excessive Loading Delay: When offline, AVPlayer attempts to load resources for up to 60 seconds before playing the locally available segments Asset Loss: Sometimes AVPlayer completely loses the asset reference and fails to play the video on subsequent attempts Inconsistent Behavior: The same partially downloaded asset might play immediately in one session but take 30+ seconds in another Network Activity Despite Offline Settings: Despite configuring options to prevent network usage, AVPlayer still appears to be attempting network connections These issues severely impact our offline user experience, especially for users with intermittent connectivity. Technical Details Implementation Context Our app downloads HLS videos for offline viewing using AVAssetDownloadTask. We store the downloaded content locally and maintain a dictionary mapping of file identifiers to local paths. When attempting to play these videos offline, we experience the described issues. Current Implementation Here's our current implementation for playing the videos: - (void)presentNativeAvplayerForVideo:(Video *)video navContext:(NavContext *)context { NSString *localPath = video.localHlsPath; if (localPath) { NSURL *videoURL = [NSURL URLWithString:localPath]; NSDictionary *options = @{ AVURLAssetPreferPreciseDurationAndTimingKey: @YES, AVURLAssetAllowsCellularAccessKey: @NO, AVURLAssetAllowsExpensiveNetworkAccessKey: @NO, AVURLAssetAllowsConstrainedNetworkAccessKey: @NO }; AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:options]; AVPlayerViewController *playerViewController = [[AVPlayerViewController alloc] init]; NSArray *keys = @[@"duration", @"tracks"]; [asset loadValuesAsynchronouslyForKeys:keys completionHandler:^{ dispatch_async(dispatch_get_main_queue(), ^{ AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:asset]; AVPlayer *player = [AVPlayer playerWithPlayerItem:playerItem]; playerViewController.player = player; [player play]; }); }]; playerViewController.modalPresentationStyle = UIModalPresentationFullScreen; [context presentViewController:playerViewController animated:YES completion:nil]; } } Attempted Solutions We've tried several approaches to mitigate these issues: Modified Asset Options: NSDictionary *options = @{ AVURLAssetPreferPreciseDurationAndTimingKey: @NO, // Changed to NO AVURLAssetAllowsCellularAccessKey: @NO, AVURLAssetAllowsExpensiveNetworkAccessKey: @NO, AVURLAssetAllowsConstrainedNetworkAccessKey: @NO, AVAssetReferenceRestrictionsKey: @(AVAssetReferenceRestrictionForbidRemoteReferenceToLocal) }; Skipped Asynchronous Key Loading: AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:asset automaticallyLoadedAssetKeys:nil]; Modified Player Settings: player.automaticallyWaitsToMinimizeStalling = NO; [playerItem setPreferredForwardBufferDuration:2.0]; Added Network Resource Restrictions: playerItem.canUseNetworkResourcesForLiveStreamingWhilePaused = NO; Used File URLs Instead of HTTP URLs where possible Despite these attempts, the issues persist. Expected vs. Actual Behavior Expected Behavior: AVPlayer should immediately begin playback of locally available HLS segments When offline, it should not attempt to load from network for more than a few seconds Once an asset is successfully played, it should be reliably available for future playback Actual Behavior: AVPlayer waits 10-60 seconds before playing locally available segments Network activity is observed despite all network-restricting options Sometimes the player fails completely to play a previously available asset Behavior is inconsistent between playback attempts with the same asset Questions: What is the recommended approach for playing partially downloaded HLS content offline with minimal delay? Is there a way to force AVPlayer to immediately use available local segments without attempting to load from the network? Are there any known issues with AVPlayer losing references to locally stored HLS assets? What diagnostic steps would you recommend to track down the specific cause of these delays? Does AVFoundation have specific timeouts for offline HLS playback that could be configured? Any guidance would be greatly appreciated as this issue is significantly impacting our user experience. Device Information iOS Versions Tested: 14.5 - 18.1 Device Models: iPhone 12, iPhone 13, iPhone 14, iPhone 15 Xcode Version: 15.3-16.2.1

Is there any way for me to use an AutoMix api in my IOS apps, I would play tracks using the Apple Music api and use AutoMix to attempt to merge tracks. Is this feature/api available to developers.

I need to implement a solution through an API or custom driver to completely block out the built-in speakers and microphone of Mac, because I need other apps to use specified external devices as audio input and output. Is there a way to achieve this requirement? What I mean is that even in system preferences, it should not be possible to choose the built-in microphone and speakers; only my external device can be used.

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

Hey everyone, I'm encountering an issue with audio sample rate conversion that I'm hoping someone can help with. Here's the breakdown: Issue Description: I've installed a tap on an input device to convert audio to an optimal sample rate. There's a converter node added on top of this setup. The problem arises when joining Zoom or FaceTime calls—the converter gets deallocated from memory, causing the program to crash. Symptoms: The converter node is being deallocated during video calls. The program crashes entirely when this happens. Traditional methods of monitoring sample rate changes (tracking nominal or actual sample rates) aren't working as expected. The Big Challenge: I can't figure out how to properly monitor sample rate changes. Listeners set up to track these changes don't trigger when the device joins a Zoom or FaceTime call. Please, if anyone has experience with this or knows a solution, I'd really appreciate your help. Thanks in advance! ⁠

Overview We are producing audio in real time from an editing application and are trying to put that on an HLS stream. We attempt to submit PCM samples through an audio writer but are getting a crash after a select number of samples have been appended. Depending on the number of audio frames in the PCM buffer, we might get more iterations before the crash but it always has the same traceback (see below). Code The setup is rather simple. We took inspiration from a few sources around the web. NSMutableDictionary *audio = [[NSMutableDictionary alloc] init]; [audio setObject:@(kAudioFormatMPEG4AAC) forKey:AVFormatIDKey]; [audio setObject:[NSNumber numberWithInt:config.audioSampleRate] // 48000 forKey:AVSampleRateKey]; [audio setObject:[NSNumber numberWithInt:config.audioChannels] // 2 forKey:AVNumberOfChannelsKey]; [audio setObject:@160000 forKey:AVEncoderBitRateKey]; m_audioConfig = [[NSDictionary alloc] initWithDictionary:audio]; m_audio = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeAudio outputSettings:m_audioConfig]; AVAudioFrameCount audioFrames = BUFFER_SAMPLES * bCount; AVAudioPCMBuffer *pcmBuffer = [[AVAudioPCMBuffer alloc] initWithPCMFormat:m_full.pcmFormat frameCapacity:audioFrames]; pcmBuffer.frameLength = pcmBuffer.frameCapacity; AudioChannelLayout layout; memset(&layout, 0, sizeof(layout)); layout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo; CMFormatDescriptionRef format; OSStatus stats = CMAudioFormatDescriptionCreate( kCFAllocatorDefault, pcmBuffer.format.streamDescription, sizeof(layout), &layout, 0, nil, nil, &format ); for (int i = 0; i < bCount; i++) { AudioPCM pcm; audioCallback->callback(pcm); memcpy(*(pcmBuffer.int16ChannelData) + (bufferSize * i), pcm.data, bufferSize); } size_t samplesConsumed = BUFFER_SAMPLES * bCount; CMSampleBufferRef sampleBuffer; CMSampleTimingInfo timing; timing.duration = CMTimeMake(1, config.audioSampleRate); timing.presentationTimeStamp = presentationTime; timing.decodeTimeStamp = kCMTimeInvalid; OSStatus ostatus = CMSampleBufferCreate( kCFAllocatorDefault, nil, false, nil, nil, format, (CMItemCount)pcmBuffer.frameLength, 1, &timing, 0, nil, &sampleBuffer ); //// ostatus = CMSampleBufferSetDataBufferFromAudioBufferList( sampleBuffer, kCFAllocatorDefault, kCFAllocatorDefault, kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment, pcmBuffer.audioBufferList ); if (ostatus != noErr) { NSLog(@"fill audio sample from buffer list failed: %s", logAudioError(ostatus)); return; } ostatus = CMSampleBufferSetDataReady(sampleBuffer); if (ostatus != noErr) { NSLog(@"set sample buffer ready failed: %s", logAudioError(ostatus)); return; } // Finally we can attach it, then shove the presentation time forward [m_audio appendSampleBuffer:sampleBuffer]; The Crash The crash points towards some level of deallocation when the conversion tooling is done or has enough samples to process an output packet? It's had to say. 0 caulk 0x1a1e9532c caulk::alloc::tiered_allocator<caulk::alloc::size_range_tier<0ul, 1008ul, caulk::alloc::tree_allocator<caulk::alloc::chunk_allocator<caulk::alloc::page_allocator, caulk::alloc::bitmap_allocator, caulk::alloc::embed_block_memory, 16384ul, 16ul, 6ul>>>, caulk::alloc::size_range_tier<1009ul, 256000ul, caulk::alloc::guarded_edges_allocator<caulk::alloc::consolidating_free_map<caulk::alloc::page_allocator, 10485760ul>, 4ul>>, caulk::alloc::tracking_allocator<caulk::alloc::page_allocator>>::deallocate(caulk::alloc::block, unsigned long) + 636 1 AudioToolboxCore 0x1993fbfe4 ExtendedAudioBufferList_Destroy + 112 2 AudioToolboxCore 0x1993d5fe0 std::__1::__optional_destruct_base<ACCodecOutputBuffer, false>::~__optional_destruct_base[abi:ne180100]() + 68 3 AudioToolboxCore 0x1993d5f48 acv2::CodecConverter::~CodecConverter() + 196 4 AudioToolboxCore 0x1993d5e5c acv2::CodecConverter::~CodecConverter() + 16 5 AudioToolboxCore 0x1992574d8 std::__1::vector<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>, std::__1::allocator<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>>>::__clear[abi:ne180100]() + 84 6 AudioToolboxCore 0x199259acc acv2::AudioConverterChain::RebuildConverterChain(acv2::ChainBuildSettings const&) + 116 7 AudioToolboxCore 0x1992596ec acv2::AudioConverterChain::SetProperty(unsigned int, unsigned int, void const*) + 1808 8 AudioToolboxCore 0x199324acc acv2::AudioConverterV2::setProperty(unsigned int, unsigned int, void const*) + 84 9 AudioToolboxCore 0x199327f08 with_resolved(OpaqueAudioConverter*, caulk::function_ref<int (AudioConverterAPI*)>) + 60 10 AudioToolboxCore 0x1993281e4 AudioConverterSetProperty + 72 11 MediaToolbox 0x1a7566c2c FigSampleBufferProcessorCreateWithAudioCompression + 2296 12 MediaToolbox 0x1a754db08 0x1a70b5000 + 4819720 13 MediaToolbox 0x1a754dab4 FigMediaProcessorCreateForAudioCompressionWithFormatWriter + 100 14 MediaToolbox 0x1a77ebb98 0x1a70b5000 + 7564184 15 MediaToolbox 0x1a7804158 0x1a70b5000 + 7663960 16 MediaToolbox 0x1a7801da0 0x1a70b5000 + 7654816 17 AVFCore 0x1ada530c4 -[AVFigAssetWriterTrack addSampleBuffer:error:] + 192 18 AVFCore 0x1ada55164 -[AVFigAssetWriterAudioTrack _flushPendingSampleBuffersReturningError:] + 500 19 AVFCore 0x1ada55354 -[AVFigAssetWriterAudioTrack addSampleBuffer:error:] + 472 20 AVFCore 0x1ada4ebf0 -[AVAssetWriterInputWritingHelper appendSampleBuffer:error:] + 128 21 AVFCore 0x1ada4c354 -[AVAssetWriterInput appendSampleBuffer:] + 168 22 lib_devapple_hls.dylib 0x115d2c7cc detail::AppleHLSImplementation::audioRuntime() + 1052 23 lib_devapple_hls.dylib 0x115d2d094 void* std::__1::__thread_proxy[abi:ne180100]<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct>>, void (detail::AppleHLSImplementation::*)(), detail::AppleHLSImplementation*>>(void*) + 72 24 libsystem_pthread.dylib 0x196e5b2e4 _pthread_start + 136 Any insight would be welcome!

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() } }

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! } } }) }

Hello All, It seems that it's "very easy" (😬) to implement a little Swift code inside the prepared AU using Xcode 16.2 on Sequoia 15.1.1 and a Mac Studio M1 Ultra, but my issue is that I finally don't know... where. The documentation says that I've to find the AudioUnitViewController.swift file and then modify the render block : audioUnit.renderBlock = { (numFrames, ioData) in // Process audio here } in the Xcode project automatically generated, but I didn't find such a file... If somebody can help me in showing where is the file to be modified, I'll be very grateful ! Thank you very much. J

Hi, On macOS I used to open MP3 and MP4 files with ExtAudioFile. For a few years it doesn't work anymore. So I decided to try different macOS API using the AudioFileID of AudioToolbox framework. I decided to write a test: https://gist.github.com/joelkraehemann/7f5b241b52ca38c3a765c138fb647588 It fails right here: AudioFileOpenWithCallbacks() By telling OSStatus error 1954115647, which means kAudioFileUnsupportedFileTypeError. The filename was set to an MP4 file: ~/Music/test.mp4 Howto fix this? regards, Joël

My current app implements a custom video player, based on a AVSampleBufferRenderSynchronizer synchronising two renderers: an AVSampleBufferDisplayLayer receiving decoded CVPixelBuffer-based video CMSampleBuffers, and an AVSampleBufferAudioRenderer receiving decoded lpcm-based audio CMSampleBuffers. The AVSampleBufferRenderSynchronizer is started when the first image (in presentation order) is decoded and enqueued, using avSynchronizer.setRate(_ rate: Float, time: CMTime), with rate = 1 and time the presentation timestamp of the first decoded image. Presentation timestamps of video and audio sample buffers are consistent, and on most streams, the audio and video are correctly synchronized. However on some network streams, on iOS, the audio and video aren't synchronized, with a time difference that seems to increase with time. On the other hand, with the same player code and network streams on macOS, the synchronization always works fine. This reminds me of something I've read, about cases where an AVSampleBufferRenderSynchronizer could not synchronize audio and video, causing them to run with independent and potentially drifting clocks, but I cannot find it again. So, any help / hints on this sync problem will be greatly appreciated! :)

I am following the Apple sample code and trying to add a manual focus lens position slider: @available(iOS 18.0, *) private func addCameraControls() { if !self.session.controls.isEmpty { for control in self.session.controls { self.session.removeControl(control) } } self.cameraControlFocusSlider = nil //Focus Slider if self.videoDevice!.isLockingFocusWithCustomLensPositionSupported { self.cameraControlFocusSlider = AVCaptureSlider("Focus", symbolName: "dot.square", in: 0.0...1.0) self.cameraControlFocusSlider!.setActionQueue(self.sessionQueue) { focusValue in //Do manual focus } if self.session.canAddControl(self.cameraControlFocusSlider!) { self.session.addControl(self.cameraControlFocusSlider!) } } } So there are these AVCaptureSessionControlsDelegate methods: final func sessionControlsDidBecomeActive(_ session: AVCaptureSession) { print ("sessionControlsDidBecomeActive") } final func sessionControlsWillEnterFullscreenAppearance(_ session: AVCaptureSession) { print ("sessionControlsWillEnterFullscreenAppearance") } final func sessionControlsWillExitFullscreenAppearance(_ session: AVCaptureSession) { print ("sessionControlsWillExitFullscreenAppearance") } final func sessionControlsDidBecomeInactive(_ session: AVCaptureSession) { print ("sessionControlsDidBecomeInactive") } So when self.cameraControlFocusSlider is presented, I have to show the current value of the lense position. Lens position can change from auto focus and also from manual focus by the user using the app UI. Is there a way to see if self.cameraControlFocusSlider is active or being used? Please note that I will have more than one AVCaptureSlider in the final code.

I am trying to achieve an animated gradient effect that changes values over time based on the current seconds. I am also using AVPlayer and AVMutableVideoComposition along with custom instruction and class to generate the effect. I didn't want to load any video file, but rather generate a custom video with my own set of instructions. I used Metal Compute shaders to generate the effects and make the video to be 20 seconds. However, when I run the code, I get a frozen player with the gradient applied, but when I try to play the video, I get this warning in the console :- Visual isTranslatable: NO; reason: observation failure: noObservations Here is the screenshot :- My entire code :- import AVFoundation import Metal class GradientVideoCompositorTest: NSObject, AVVideoCompositing { var sourcePixelBufferAttributes: [String: Any]? = [ kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32BGRA ] var requiredPixelBufferAttributesForRenderContext: [String: Any] = [ kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32BGRA ] private var renderContext: AVVideoCompositionRenderContext? private var metalDevice: MTLDevice! private var metalCommandQueue: MTLCommandQueue! private var metalLibrary: MTLLibrary! private var metalPipeline: MTLComputePipelineState! override init() { super.init() setupMetal() } func setupMetal() { guard let device = MTLCreateSystemDefaultDevice(), let queue = device.makeCommandQueue(), let library = try? device.makeDefaultLibrary(), let function = library.makeFunction(name: "gradientShader") else { fatalError("Metal setup failed") } self.metalDevice = device self.metalCommandQueue = queue self.metalLibrary = library self.metalPipeline = try? device.makeComputePipelineState(function: function) } func renderContextChanged(_ newRenderContext: AVVideoCompositionRenderContext) { renderContext = newRenderContext } func startRequest(_ request: AVAsynchronousVideoCompositionRequest) { guard let outputPixelBuffer = renderContext?.newPixelBuffer(), let metalTexture = createMetalTexture(from: outputPixelBuffer) else { request.finish(with: NSError(domain: "com.example.gradient", code: -1, userInfo: nil)) return } var time = Float(request.compositionTime.seconds) renderGradient(to: metalTexture, time: time) request.finish(withComposedVideoFrame: outputPixelBuffer) } private func createMetalTexture(from pixelBuffer: CVPixelBuffer) -> MTLTexture? { var texture: MTLTexture? let width = CVPixelBufferGetWidth(pixelBuffer) let height = CVPixelBufferGetHeight(pixelBuffer) let textureDescriptor = MTLTextureDescriptor.texture2DDescriptor( pixelFormat: .bgra8Unorm, width: width, height: height, mipmapped: false ) textureDescriptor.usage = [.shaderWrite, .shaderRead] CVPixelBufferLockBaseAddress(pixelBuffer, .readOnly) if let textureCache = createTextureCache(), let cvTexture = createCVMetalTexture(from: pixelBuffer, cache: textureCache) { texture = CVMetalTextureGetTexture(cvTexture) } CVPixelBufferUnlockBaseAddress(pixelBuffer, .readOnly) return texture } private func renderGradient(to texture: MTLTexture, time: Float) { guard let commandBuffer = metalCommandQueue.makeCommandBuffer(), let commandEncoder = commandBuffer.makeComputeCommandEncoder() else { return } commandEncoder.setComputePipelineState(metalPipeline) commandEncoder.setTexture(texture, index: 0) var mutableTime = time commandEncoder.setBytes(&mutableTime, length: MemoryLayout<Float>.size, index: 0) let threadsPerGroup = MTLSize(width: 16, height: 16, depth: 1) let threadGroups = MTLSize( width: (texture.width + 15) / 16, height: (texture.height + 15) / 16, depth: 1 ) commandEncoder.dispatchThreadgroups(threadGroups, threadsPerThreadgroup: threadsPerGroup) commandEncoder.endEncoding() commandBuffer.commit() } private func createTextureCache() -> CVMetalTextureCache? { var cache: CVMetalTextureCache? CVMetalTextureCacheCreate(kCFAllocatorDefault, nil, metalDevice, nil, &cache) return cache } private func createCVMetalTexture(from pixelBuffer: CVPixelBuffer, cache: CVMetalTextureCache) -> CVMetalTexture? { var cvTexture: CVMetalTexture? let width = CVPixelBufferGetWidth(pixelBuffer) let height = CVPixelBufferGetHeight(pixelBuffer) CVMetalTextureCacheCreateTextureFromImage( kCFAllocatorDefault, cache, pixelBuffer, nil, .bgra8Unorm, width, height, 0, &cvTexture ) return cvTexture } } class GradientCompositionInstructionTest: NSObject, AVVideoCompositionInstructionProtocol { var timeRange: CMTimeRange var enablePostProcessing: Bool = true var containsTweening: Bool = true var requiredSourceTrackIDs: [NSValue]? = nil var passthroughTrackID: CMPersistentTrackID = kCMPersistentTrackID_Invalid init(timeRange: CMTimeRange) { self.timeRange = timeRange } } func createGradientVideoComposition(duration: CMTime, size: CGSize) -> AVMutableVideoComposition { let composition = AVMutableComposition() let instruction = GradientCompositionInstructionTest(timeRange: CMTimeRange(start: .zero, duration: duration)) let videoComposition = AVMutableVideoComposition() videoComposition.customVideoCompositorClass = GradientVideoCompositorTest.self videoComposition.renderSize = size videoComposition.frameDuration = CMTime(value: 1, timescale: 30) // 30 FPS videoComposition.instructions = [instruction] return videoComposition } #include <metal_stdlib> using namespace metal; kernel void gradientShader(texture2d<float, access::write> output [[texture(0)]], constant float &time [[buffer(0)]], uint2 id [[thread_position_in_grid]]) { float2 uv = float2(id) / float2(output.get_width(), output.get_height()); // Animated colors based on time float3 color1 = float3(sin(time) * 0.8 + 0.1, 0.6, 1.0); float3 color2 = float3(0.12, 0.99, cos(time) * 0.9 + 0.3); // Linear interpolation for gradient float3 gradientColor = mix(color1, color2, uv.y); output.write(float4(gradientColor, 1.0), id); }

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: )