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Coverting CVPixelBuffer 2VUY to a Metal Texture
I am working on a project for macOS where I am taking an AVCaptureSession's CVPixelBuffer and I need to convert it into a MTLTexture for rendering. On macOS the pixel format is 2vuy, there does not seem to be a clear format conversion while converting to a metal texture. I have been able to convert it to a texture but the color space seems to be off as it is rendering distorted colors with a double image. I believe 2vuy is a single pane color space and I have tried to account for that, but I am unaware of what is off. I have attached The CVPixelBuffer and The distorted MTLTexture along with a laundry list of errors. On iOS my conversions are fine, it is only the macOS 2vuy pixel format that seems to have issues. My code for the conversion is also attached. If there are any suggestions or guidance on how to properly convert a 2vuy CVPixelBuffer to a MTLTexture I would greatly appreciate it. Many Thanks Conversion_Logs.txt ConversionCode.swift
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144
Apr ’25
SCStreamDelegetate stream:didStopWithError receiving null pointer for error
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
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514
Mar ’25
Why Does AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps Occur on iPhone?
Hi everyone, We're encountering an unexpected issue with our iPhone-only camera app: 👉 TimeMark - Photo Proof https://apps.apple.com/us/app/timemark-photo-proof/id6446071834 Problem Description: Our app uses a full-screen camera view via AVCaptureSession. In some cases reported by users, the camera fails immediately upon app launch, and we receive this interruption reason: AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps According to the Apple documentation https://developer.apple.com/documentation/avfoundation/avcapturesession/interruptionreason/videodevicenotavailablewithmultipleforegroundapps?language=objc , this interruption typically occurs when the app is running in a multi-app layout such as Slide Over, Split View, or Picture in Picture — all of which are iPad-only features. However, this issue is being reported on iPhones, and our app does not support iPad at all. Also noted in the documentation: "Given your present AVCaptureSession configuration, the session may only be run if your app occupies the full screen." Additional Context: The issue occurs immediately on app launch, before the user can interact with the camera. We don’t enable multitaskingCameraAccessEnabled. We are 100% sure this is happening on iPhone, not iPad. It’s hard to reproduce; users report it happening sporadically. Locally, we tried playing Picture-in-Picture videos (e.g., Safari/YouTube) before launching our app, but we could not reproduce the issue. Questions: Why is this interruption reason occurring on iPhone, which doesn’t officially support Slide Over or Split View? Could this be caused by some system-level multitasking or resource contention (e.g., Picture in Picture from FaceTime or Safari)? Would enabling multitaskingCameraAccessEnabled help prevent this issue on iPhone, even though it's designed for iPad? Enabling multitaskingCameraAccessEnabled seems to require enabling UIBackgroundModes → voip. Would adding this background mode cause any App Store review risk or rejection if our app doesn't actually use VoIP functionality? Any help, insight, or suggestions would be greatly appreciated. Thanks in advance!
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1w
CarPlay CPNowPlayingTemplate show wrong command buttons
i have a CarPlay implementation eand I want to show previous/next track button on player UI MPRemoteCommandCenter.shared().seekForwardCommand.isEnabled = false MPRemoteCommandCenter.shared().seekBackwardCommand.isEnabled = false MPRemoteCommandCenter.shared().previousTrackCommand.isEnabled = true MPRemoteCommandCenter.shared().nextTrackCommand.isEnabled = true It works correctly on CarPlay simulator , but on some car only SEEK button are shown . I have to suppose that it is that a problem on the car side , but I would ask about your opinion , maybe there is some pieces I'm missing
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Jan ’25
AVAudioEngine Voice Processing Fails with Mismatched Input/Output Devices: AggregateDevice Channel Count Mismatch
I'm encountering errors while using AVAudioEngine with voice processing enabled (setVoiceProcessingEnabled(true)) in scenarios where the input and output audio devices are not the same. This issue arises specifically with mismatched devices, preventing the application from functioning as expected. Works: Paired devices (e.g., MacBook Pro mic → MacBook Pro speakers) Fails: Mismatched devices (e.g., AirPods mic → MacBook Pro speakers) When using paired input and output devices: The setup works as expected. Example: MacBook Pro microphone → MacBook Pro speakers. When using mismatched devices: AVAudioEngine setup fails during aggregate device construction. Example: AirPods microphone → MacBook Pro speakers. Error logs indicate a channel count mismatch. Here are the partial logs. Due to the content limit, I cannot post the entire logs. AUVPAggregate.cpp:1000 client-side input and output formats do not match (err=-10875) AUVPAggregate.cpp:1036 err=-10875 AVAEInternal.h:109 [AVAudioEngineGraph.mm:1344:Initialize: (err = PerformCommand(*outputNode, kAUInitialize, NULL, 0)): error -10875 AggregateDevice.mm:329 Failed expectation of constructed aggregate (312): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (312): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) AggregateDevice.mm:182 error fetching default pair AggregateDevice.mm:329 Failed expectation of constructed aggregate (336): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (336): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) AUHAL.cpp:1782 ca_verify_noerr: [AudioDeviceSetProperty(mDeviceID, NULL, 0, isInput, kAudioDevicePropertyIOProcStreamUsage, theSize, theStreamUsage), 560227702] AudioHardware-mac-imp.cpp:3484 AudioDeviceSetProperty: no device with given ID AUHAL.cpp:1782 ca_verify_noerr: [AudioDeviceSetProperty(mDeviceID, NULL, 0, isInput, kAudioDevicePropertyIOProcStreamUsage, theSize, theStreamUsage), 560227702] AggregateDevice.mm:182 error fetching default pair AggregateDevice.mm:329 Failed expectation of constructed aggregate (348): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (348): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) Is it possible to use voice processing with different input/output devices? If yes, are there any specific configurations required to handle mismatched devices? How can we resolve channel count mismatch errors during aggregate device construction? Are there settings or API adjustments to enforce compatibility between input/output devices? Are there any workarounds or alternative approaches to achieve voice processing functionality with mismatched devices? For instance, can we force an intermediate channel configuration or downmix input/output formats?
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648
Mar ’25
I cannot revoke Apple Fairplay Streaming certificate
We move to another streaming service and need to deliver a ASK, .PEM &key, and CRT to enable DRM. Now the issue is that we don't have that information anymore. Most logical would be to revoke the current certificate and create a new one. Unfortunately for Fairplay Streaming Certificates there is no revoke button. We asked developer support who isn't able to help. We then did a request to revoke as described in article 2.7 of the Apple Developer Program License Agreement. They can only do this when the certificate is compromised. So now we are stuck. Anyone out there who had the same issue and found a solution? Your help is much appreciated.
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619
Jan ’25
AVPlayer unpredictable range requests on iOS when streaming *.mov file
Hi all, I'm trying to diagnose and resolve an issue with stuttering video playback using the standard AVPlayer. The video in question is a 4K, 39-second file in *.mov format, being played on an iOS device. It's served via a local HTTP server that proxies requests to a backend to fetch and process the content. The project uses end-to-end encrypted storage, which necessitates the proxy for handling data processing. While playback in offline scenarios is smooth, we are encountering issues with smooth playback during streaming. The same video streams smoothly on other platforms using the same connection, so network limitations are not a factor. On iOS, playback is consistently choppy, with pauses every 1-3 seconds. The video does not appear to buffer adequately for smooth playback. One particularly curious aspect is the seemingly random pattern of Content-Range requests made by the AVPlayer when streaming the video. Below is an example of the range requests:
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449
Apr ’25
Playback Issues for DRM content when sending CMCD
Since iOS and tvOS 18, CMCD can now be automatically sent by AVPlayer (https://developer.apple.com/streaming/Whats-new-HLS.pdf). However, after enabling CMCD, our streams occasionally fail with the following error: CoreMediaErrorDomain Error -17383 This issue appears to affect only DRM-protected (FairPlay) streams so far. We activate CMCD via the resource loader of an AVURLAsset, before assigning the item to an AVPlayer. Unfortunately, we haven’t found a reliable way to reproduce the issue, and we’ve been unable to gather any useful diagnostic information. Has anyone else observed this behavior when enabling CMCD on FairPlay streams?
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1w
Configuring CaptureVideoDelegate to avoid gamma/transfer function
I'm working on an application that uses the iPhone camera for scientific purposes - and, as a result would like to receive video in as unprocessed format as possible. In particular, I'm interested in getting pixel buffers that contain pretty much the bayer data as the sensor sees it - with the minimum processing of color possible. Currently we configure the AVCaptureDevice to fix the focus and exposure, use a low ISO with no gain and set the white balance gains to 1. AVCaptureVideoDataOutput is using 32BGRA. What I'd like to do is remove any additional color and brightness processing such that the data is effectively processed with a linear transfer function (i.e. gamma function is 1). I thought that this might be down to using the AVCaptureDevice activeColorSpace - we currently use P3_D65 for this. But there only seems to be a few choices (e.g. sRGB, HLG_BT2020) all of which I think affect the gamma. So: is it possible to control or specify the gamma / transfer function when using CaptureVideoDelegate? if not, does one of the color space settings have a defined gamma function that I can effectively reverse it from the pixel data without losing too much information? or is there a better way to capture video-ish speed images (15-30fps) from the camera sensor that skips processing like this? Many thanks for any suggestions.
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82
Mar ’25
AVSpeechSynthesizer - just not working on 15.1.1
So get a swift file and put this in it import Foundation import AVFoundation let synthesizer = AVSpeechSynthesizer() let utterance = AVSpeechUtterance(string: "Hello, testing speech synthesis on macOS.") if let voice = AVSpeechSynthesisVoice(identifier: "com.apple.voice.compact.en-GB.Daniel") { utterance.voice = voice print("Using voice: \(voice.name), \(voice.language)") } else { print("Daniel voice not found on macOS.") } synthesizer.speak(utterance) I get no speech output and this log output Error reading languages in for local resources. Error reading languages in for local resources. Using voice: Daniel, en-GB Program ended with exit code: 0 Why? and whats with "Error reading languages in for local resources." ?
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939
Dec ’24
iOS 17 camera capture assertions and issues
Hello, Starting in iOS 17, our application started having some issue publishing to our video session. More specifically the video capture seems to be broken in some, but not all sessions. What's troubling is that we're seeing that it fails consistently every 4 sessions. It also fails silently, without reporting any problems to the app. We only notice that there are no frames being rendered or sent to the remote devices. Here's what shows-up in the console: <<<< FigCaptureSourceRemote >>>> Fig assert: "! storage->connectionDied" at bail (FigCaptureSourceRemote.m:235) - (err=0) <<<< FigCaptureSourceRemote >>>> Fig assert: "err == 0 " at bail (FigCaptureSourceRemote.m:253) - (err=-16453) Anyone seeing this? Any idea what could be the cause? Our sessions work perfectly on iOS16 and below. Thanks
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1.3k
2w
Question about PT Framework channel tone behaviour
I've been wondering if there is a way to modify or even disable tones for indicating channel states. The behaviour regarding tones seems like a black box with little documentation. During migration to Apple's PT Framework we've noticed that there are few scenarios where a tone is played which doesn't match certain certifications. For example; moving from a channel to another produces a tone which would fail a test case. I understand the reasoning fully, as it marks that the channel is ready to transmit or receive, but this doesn't mirror the behaviour of TETRA which would be wanted in this case. I'm also wondering if there would be any way to directly communicate feedback regarding PT Framework?
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3w
iOS26中ALAssetsLibrary 编译报错问题
mac os 系统版本:26.0 (25A354) Xcode版本:Version 26.0 (17A324) 项目编译报错 `SwiftExplicitDependencyCompileModuleFromInterface arm64 /Users/zhz/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/AssetsLibrary-HTIJ05N58KN3.swiftmodule /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:10:25: error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead 8 | public import _StringProcessing 9 | public import _SwiftConcurrencyShims 10 | extension AssetsLibrary.ALAssetsLibrary { | `- error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead 11 | #if compiler(>=5.3) && $NonescapableTypes 12 | @available(iOS, introduced: 9.0, deprecated: 9.0, obsoleted: 26.0) /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/System/Library/Frameworks/AssetsLibrary.framework/Headers/ALAssetsLibrary.h:80:12: note: 'ALAssetsLibrary' was obsoleted in iOS 26.0 78 | 79 | OS_EXPORT AL_DEPRECATED(4, "Use PHPhotoLibrary from the Photos framework instead") 80 | @interface ALAssetsLibrary : NSObject { | `- note: 'ALAssetsLibrary' was obsoleted in iOS 26.0 81 | @package 82 | id _internal; /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:1:1: error: failed to build module 'AssetsLibrary'; this SDK is not supported by the compiler (the SDK is built with 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.17.14 clang-1700.3.17.1)', while this compiler is 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.19.9 clang-1700.3.19.1)'). Please select a toolchain which matches the SDK.
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1w
Selecting an appropriate AVCaptureDeviceFormat
My app currently captures video using an AVCaptureSession set with the AVCaptureSessionPreset1920x1080 preset. However, I'd like to update this behavior, such that video can be recorded at a range of different resolutions. There isn't a preset aligning to each desired resolution, so I thought I'd instead directly set the AVCaptureDeviceFormat. For any desired resolution, I would find the format that is closest without going under the desired resolution, and then crop it down as a post-processing step. However, what I've observed is that there can be a range of available formats for a device at each resolution, with various differing settings. Presumably there is logic within AVCaptureSession that selects a reasonable default based on all these different settings, but since I am applying the format directly, I think I don't have a way to make use of that default logic? And it is undocumented? Does this mean that the only way to select a format is to implement a comparison function that considers all different values of all different properties on AVCaptureDeviceFormat, and then sort the formats according to this comparator? If so, what if some new property is added to AVCaptureDeviceFormat in the future? The sort would not take this new property into account, and the function might select a format with some new undesired property. Are there any guarantees about what types for formats will be supported on a device? For example, can I take for granted that a '420v' format will exist at each resolution? If so I could filter the formats down only to those with this setting without risking filtering out all of the supported formats. I suspect I may be missing something obvious. Any help would be greatly appreciated!
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731
Dec ’24
Cannot load iTunesLibrary on macOS Sequoia 15.1
I use the iTunes Library framework in one of my apps, starting with macOS Sequoia 15.1 i can't create the ITLibrary object anymore with the following error: Connection to amplibraryd was interrupted. clientName:iTunesLibrary(ITLibraryLoader) Error connecting to the server via proxy object Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.amp.library.framework" UserInfo={NSDebugDescription=connection to service named com.apple.amp.library.framework} configure failed: Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.apple.amp.library.framework" UserInfo={NSDebugDescription=connection to service named com.apple.amp.library.framework} I created a new sandboxed macOS app, added the music folder read permission and it reproduced the error: import SwiftUI import iTunesLibrary @main struct ITLibraryLoaderApp: App { var body: some Scene { WindowGroup { ContentView() } } } struct ContentView: View { var body: some View { Button("Load ITLibrary") { loadLibrary() } } func loadLibrary() { do { let _ = try ITLibrary(apiVersion: "1.0", options: .none) } catch { print(error) } } } I restarted my developer machine and the music app with no luck.
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937
Jan ’25
Handling AVAudioEngine Configuration Change
Hi all, I have been quite stumped on this behavior for a little bit now, so thought it best to share here and see if someone more experience with AVAudioEngine / AVAudioSession can weigh in. Right now I have a AVAudioEngine that I am using to perform some voice chat with and give buffers to play. This works perfectly until route changes start to occur, which causes the AVAudioEngine to reset itself, which then causes all players attached to this engine to be stopped. Once a AVPlayerNode gets stopped due to this (but also any other time), all samples that were scheduled to be played then get purged. Where this becomes confusing for me is the completion handler gets called every time regardless of the sound actually being played. Is there a reliable way to know if a sample needs to be rescheduled after a player has been reset? I am not quite sure in my case what my observer of AVAudioEngineConfigurationChange needs to be doing, as this engine only handles output. All input is through a separate engine for simplicity. Currently I am storing a queue of samples as they get sent to the AVPlayerNode for playback, and after that completion checking if the player isPlaying or not. If it's playing I assume that the sound actually was played- and if not then I leave it in the queue and assume that an observer on the route change or the configuration change will realize there are samples in the queue and reset them Thanks for any feedback!
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604
Oct ’25
Mac OS Tahoe 26.0 (25A354) Sound Glitches When opening the simulator app
Hey there, I just upgraded to Mac OS Tahoe ,son an apple MacBook Pro 2019 16inch. am using IntellijIDEA and Flutter to develop a mobile app which I test on the simulator app running iOS 18.4 . the issue: when I start the simulator app. ( while in the loading phase and in the operation phase as well ), the audio from an already open YouTube tab on safari (this happens on chrome browser as well). the sound glitches and becomes Noise. a fix I found online is to kill the audio deamon on Mac OS, This works using the command: "sudo killall coreaudiod" this kills the audio process, (while the emulator is operational), then the macOS restarts the audio deamon then the audio works fine alongside with the simulator being open. I just want to ask is there a permanent fix for this? is Apple working on a fix for this in the upcoming update?
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1.1k
Oct ’25
Capturing 48mp photos with .builtInTripleCamera
I am able to capture 48mp photos using .builtInWideAngleCamera, but it seems like .builtInTripleCamera is capped at 12mp? Is there a way to capture 48mp photos using .builtInTripleCamera? Because .builtInTripleCamera provides smooth transition between cameras during zooming, and I'd like to keep this behavior. New iPhone 17 Pro have all their cameras at 48mp. Is there a chance that their .builtInTripleCamera is capable of capturing 48mp? Or is this an API limitation?
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336
Sep ’25