Summary Using AudioHardwareCreateProcessTap + AudioHardwareCreateAggregateDevice for system audio capture. During long sessions, the AudioDeviceIOProc callback continues firing normally but every PCM sample is exactly 0.0f — while the system is producing audible output. Environment Field Value macOS 26.5 Beta Hardware MacBook Air (M2) API AudioHardwareCreateProcessTap + AudioHardwareCreateAggregateDevice Tap CATapDescription, processes = [], .unmuted, private Format 48,000 Hz, Float32, interleaved stereo Aggregate anchor kAudioAggregateDeviceMainSubDeviceKey = current default output UID Observed behavior After running normally for several minutes, the stream transitions into an all-zero state: AudioDeviceIOProc continues to fire at expected cadence Frame count, timestamps (mHostTime, mSampleTime), and mDataByteSize all look normal AudioBufferList pointers are valid Every sample in every buffer is exactly 0.0f Other apps are still producing audible output through the same output device The condition may self-recover or persist until the session is stopped Confirmed via RMS logging both inside the IOProc and after the ring buffer consumer — data is zero on delivery, not introduced downstream. Example: 51-minute session on MacBook Air M2 Segment 1 (~7 min): Three all-zero periods: 60 s, 53 s, 141 s. Real PCM briefly returned between them. Segment 2 (~44 min): Two all-zero periods: 16 min 3 s, 3 min 8 s. IOProc cadence, timestamp deltas, default output UID, and kAudioDevicePropertyDeviceIsRunningSomewhere all remained normal throughout. What I have ruled out Actual silence: User was in an active video call and could hear participants through the output device. Default output device change: Monitored kAudioHardwarePropertyDefaultOutputDevice — no change during affected periods. IOProc stall: Heartbeat and kAudioDevicePropertyDeviceIsRunningSomewhere remained normal. Aggregate device destroyed: AudioObjectGetPropertyData on the aggregate UID continued returning the expected device. Tap descriptor misconfiguration: The same tap produces valid PCM earlier in the same session, so this is not a startup-time issue. Why detection is hard All-zero buffers from a broken tap are indistinguishable from legitimate silence (muted participant, waiting room, paused media). kAudioProcessPropertyIsRunningOutput reports whether a process has active output IO, not whether it is contributing non-zero samples — a muted Zoom call still reports true. Possible correlations Sample-rate renegotiation on the output device (44.1 kHz ↔ 48 kHz) when another app changes output Bluetooth device state changes (AirPods sleep/wake) where UID stays the same MacBook Air more frequently affected than MacBook Pro Always occurs after extended uptime — first few minutes are consistently clean Current workaround Full teardown and rebuild restores real PCM. Restarting the IOProc alone or recreating only the aggregate device is not reliable — both the Process Tap and Aggregate Device must be destroyed and recreated. 1. AudioDeviceStop 2. AudioDeviceDestroyIOProcID 3. AudioHardwareDestroyAggregateDevice 4. AudioHardwareDestroyProcessTap 5. AudioHardwareCreateProcessTap 6. AudioHardwareCreateAggregateDevice 7. Create + start new IOProc Applying this automatically is risky because it cannot be reliably distinguished from legitimate silence. Questions Expected failure mode? Can a Process Tap continue delivering zero-filled buffers while the system output is audible? Is this expected under certain device or routing conditions? Detection signal? Is there any HAL property, notification, or diagnostic counter that distinguishes "sources are genuinely silent" from "the tap data path has stopped receiving the real mix"? Targeted recovery? Is there a supported way to re-anchor or reset the tap data path without destroying and recreating both objects? Full rebuild as intended workaround? If so, it would help to confirm this so developers can converge on a consistent approach. Mixer activity signal? kAudioProcessPropertyIsRunningOutput reflects IO registration, not sample contribution. Is there any AudioProcess property that indicates a process is currently delivering non-zero audio to the system mixer?

Hello, I am developing Uniq Intercom, a voice-only group communication app for motorcyclists (always-on intercom over WebRTC, used continuously for multi-hour rides). I am seeking guidance on an iOS audio session and CarPlay HID interaction I have not been able to resolve through documented APIs. Problem: As soon as my app activates the microphone (yellow recording indicator visible), iOS appears to classify the app as a real-time communication participant and CarPlay re-routes the steering-wheel / handlebar HID transport buttons (left / right / ok) from the media-control role to the call-control role (answer/decline). Because I do not register a CallKit / LiveCommunicationKit call (the session is a continuous group voice channel, not a discrete telephony call), there is no call object for those buttons to act upon — they effectively become inert. Why this matters: Motorcyclists rely on the intercom for 4–6 hour rides. CarPlay is now built into a growing number of modern motorcycles and with aftermarket display units virtually any bike, and any rider who uses any voice communication platform alongside it — Uniq Intercom, WhatsApp Call currently runs into this same handlebar button remap. With the buttons inert, the rider's only remaining option is to reach for the motorcycle's touchscreen to skip a track or change navigation — this is unsafe. The exact same remap behavior occurs during a real WhatsApp or Phone call — but for those the remap is correct (answer/decline maps to a real call). For continuous voice apps without a CallKit-style discrete call, no equivalent path exists today. As both an iOS developer and a motorcyclist, I would very much like to see this resolved — solving it would meaningfully improve safety for every rider using an iPhone with CarPlay. Configurations I have tested (all reproduce the symptom on iOS 18+ / 26 with wireless CarPlay): AVAudioSession.Category.playAndRecord + .voiceChat mode + various option combinations (duckOthers, mixWithOthers, allowBluetoothHFP, allowBluetoothA2DP, defaultToSpeaker) Same category with .videoChat mode (which @livekit/react-native defaults to) Same category with .default mode (re-applied after setAudioModeAsync to defeat any framework override) — confirmed Mode = Default for ~2 s window in audiomxd log before WebRTC's setActive cycle returned mode to .voiceChat. Buttons remained remapped during the .default window. Disabling MPRemoteCommandCenter and clearing MPNowPlayingInfoCenter.default().nowPlayingInfo JS-side override of WebRTC's global RTCAudioSessionConfiguration via @livekit/react-native's AudioSession.setAppleAudioConfiguration({audioMode: 'default'}) bridge, applied both before connect and after setAudioModeAsync to defeat library overrides In every case the audiomxd system log confirms our session goes active (Mode = VoiceChat or Default, Recording = YES), and CarPlay HID buttons are immediately remapped to call-control. The middle "OK" button remains functional because it is not part of the call-control mapping — confirming the buttons are not blocked, only re-purposed. The remap occurs the instant the iOS recording indicator appears, regardless of audio session mode. This led me to conclude the trigger is not audio session mode but the combination of microphone permission + active session + (likely) the AUVoiceIO unit instantiated by WebRTC. I cannot find a public API path to suppress this classification while maintaining the always-on continuous voice channel. My questions: Is there an entitlement or API that allows an app with active microphone capture to declare itself as a non-call media participant, keeping CarPlay HID transport buttons in the media role? Is AVAudioSession.setPrefersEchoCancelledInput(_:) (iOS 18+) the intended path for retaining platform AEC under .default mode without the focus-engine "communication priority" marking? Documentation is sparse on its CarPlay arbitration implications. Does the PushToTalk framework affect HID arbitration differently from playAndRecord + voiceChat? Our continuous-channel UX does not fit the PTT transmit-on-press model, but understanding the contrast would help. If no current API exists, is this something the iOS Audio team would consider for future SDKs? Solving this would meaningfully improve safety for motorcycle and adventure-sport users on iOS. Thank you for your time and any guidance you can offer. — Emre Erkaya / Uniq Intercom

Hi, I understand that AVPlayer/AVFoundation doesn’t natively play MPEG-DASH manifests (.mpd) today, while HLS is supported and widely documented by Apple. I’m not asking for roadmap commitments, but I’d like to understand whether there is any publicly documented rationale for not supporting DASH/MPD in AVFoundation (e.g., technical constraints, platform integration, DRM ecosystem, power/performance considerations, etc.). Questions: Is there any Apple statement / documentation explaining why DASH (MPD) isn’t supported in AVFoundation? Is Apple’s recommended approach still “provide HLS for Apple clients” (potentially sharing CMAF segments and generating separate manifests)? If there’s no public rationale, is filing Feedback Assistant the best channel for requesting MPD playback support? Thanks!

Hi everyone, I am working on an app that supports offline playback with FairPlay Streaming (FPS). I have successfully implemented the logic to download and persist the content keys (TLLV), and offline playback is working correctly using the stored persistent keys. However, I am now trying to implement a manual renewal process for these licenses, and I’ve run into an issue where the delegate methods are not being fired as expected. The Issue: I am calling contentKeySession.addContentKeyRecipient(asset) to force a renewal or re-fetch of the content key for a specific asset. Even though the asset is correctly initialized and the session is active, the AVContentKeySessionDelegate methods (specifically contentKeySession(_:didProvide:)) are not being triggered at all. My Questions: Why is the delegate not firing when adding the recipient? Is there a specific state or property the AVURLAsset needs to have (or a specific way it should be initialized) to trigger a new key request via addContentKeyRecipient? Is it possible to perform a manual license renewal triggered by a UI action (e.g., a button tap) without actually initiating playback of the asset? The goal is to allow users to refresh their licenses manually while online, ensuring the content remains playable offline before the previous license expires, all without forcing the user to start the video. Any insights or best practices for this manual renewal flow would be greatly appreciated.

Recently I received multiple user email supports because the app cannot save video to photos, they are all on iOS 26.x The code in my app around recording video and saving to Photos hasn't changed in years. I'm not able to reproduce it locally, I tried on all my available devices. In recently published build I added additional logs and it appears that all of cases that fail with 3302 have the photos access set to "Limited Access". It never happens to users with "Full Access". In that build I also added a fallback, when saving to photos fails, the app saves to Documents and it seems it works (two of my users affected users confirmed it), but it's very unfortunate. I think it kind of proves that videos aren't broken given that users are able to play them just fine. On of users says that for him saving to Photos works for 2-3 times after he reinstalls the app and then it stops working. Did anything recently changed in how we should save videos to photos? I'm using the following code. I can see in git blame that I haven't changed in since 2020 and never encountered those errors in development or heard about those issues until around 1 month ago. Thank you. PHPhotoLibrary.shared().performChanges { PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: fileURL) } completionHandler: { success, error in

Area: visionOS 26.4 · AVFoundation · AVCapture · External/UVC video Classification: Suggestion / API Enhancement Request (also: Incorrect/Missing Documentation) Device / OS: Apple Vision Pro, visionOS 26.x. Xcode 26.4.1, XROS26.4.sdk. Summary On visionOS, a third-party app cannot display two UVC USB cameras (connected through a powered USB-C hub) at the same time. Every AVFoundation path that would enable this on iPadOS is either unavailable or fails at runtime on visionOS, and there is no public non-AVFoundation fallback (no IOUSBHost, no DriverKit, no usable CoreMediaIO, no MFi path for generic UVC devices). This is a real capability gap relative to iPadOS and macOS, and Camo Studio on iPadOS (App Store ID 6450313385) demonstrates the two-camera USB-hub use case is legitimate and valuable for spatial-video/hybrid-capture workflows on Vision Pro. Steps to reproduce Connect a powered USB-C hub to Apple Vision Pro with two UVC webcams attached. Build a visionOS app that uses AVCaptureDevice.DiscoverySession(deviceTypes: [.external], …). Observe: both cameras are discovered and enumerate as distinct AVCaptureDevices. Attempt A — two independent sessions: Create two independent AVCaptureSessions, each with one AVCaptureDeviceInput and one AVCaptureVideoDataOutput, start both. Result: only one session delivers sample buffers. The other stalls silently with no error and no interruption notification. Attempt B — AVCaptureMultiCamSession with manual connections (the pattern that works on iPadOS 18+): Result: code does not compile. In XROS26.4.sdk: AVCaptureInputPort is API_UNAVAILABLE(visionos) (AVCaptureInput.h) AVCaptureInput.ports is API_UNAVAILABLE(visionos) AVCaptureDeviceInput.portsWithMediaType:sourceDeviceType:sourceDevicePosition: is API_UNAVAILABLE(macos, visionos) Therefore AVCaptureConnection(inputPorts:output:) cannot be constructed. AVCaptureMultiCamSession itself is declared API_AVAILABLE(… visionos(2.1)), which is misleading because without input-port access the manual-connection path the class requires is unreachable. Expected behavior Either of the following would resolve this, in order of preference: Expose the missing API surface on visionOS. Make AVCaptureInputPort, AVCaptureInput.ports, and AVCaptureDeviceInput.portsWithMediaType:sourceDeviceType:sourceDevicePosition: available on visionOS so the documented iPadOS multi-cam pattern compiles and runs. AVCaptureMultiCamSession is already declared available — the supporting API surface should match. Allow two concurrent plain AVCaptureSessions to each own a distinct external AVCaptureDevice. Each session binds a different hardware device, and the current serialization appears to be a software policy rather than a hardware constraint (a powered hub has bandwidth for both). Document the limit explicitly and surface a clear error or interruption reason on the stalled session so apps can fail loudly instead of appearing to work. Actual behavior AVCaptureMultiCamSession advertises visionos(2.1) availability but the APIs required to wire its connections are marked unavailable on visionOS. Two concurrent AVCaptureSessions silently deliver frames to only one session; no error is reported on the other. There is no public alternative framework on visionOS for raw UVC access to work around this: IOUSBHost.framework — not present in XROS26.4.sdk DriverKit — not present in XROS26.4.sdk IOKit — ships a stub (IOKit.tbd); no public USB device interfaces CoreMediaIO — headers are an apinotes stub on visionOS ExternalAccessory — MFi-only; generic UVC devices don't enumerate This means there is no public path, AVFoundation or otherwise, for a third-party visionOS app to display two UVC cameras at once. Impact / use cases Apple Vision Pro is uniquely suited to multi-camera monitoring and capture workflows — spatial creators, broadcast/AV producers, multi-angle reference during immersive authoring, clinical and field-recording use cases, and apps that combine a primary UVC cinema camera with a secondary UVC reference/overview angle. iPadOS already supports this via AVCaptureMultiCamSession (demonstrated shipping by Camo Studio). The current visionOS limitation pushes these workflows back to iPad or macOS and undermines Vision Pro's positioning as a pro capture/monitor environment. References iPadOS reference implementation: Apple sample Displaying Video From Connected Devices + AVCaptureMultiCamSession with manual AVCaptureConnection wiring — works on iPadOS 18+ with two UVC cameras via a powered hub. Shipping precedent: Camo Studio — two simultaneous UVC cameras via USB hub on iPad — https://apps.apple.com/us/app/camo-studio-stream-record/id6450313385 visionOS 26.4 SDK headers cited above (AVCaptureInput.h, AVCaptureSession.h).

Hello everyone, I have a question regarding the Ultra-Low Latency Frame Interpolation and Super Resolution features introduced in WWDC 2025 Session 300 (https://developer.apple.com/videos/play/wwdc2025/300/). In the video, it was mentioned that these features run on any device as long as it has iOS 26.0 or later and an Apple Silicon chipset. Based on the official support guide (https://support.apple.com/ko-kr/guide/iphone/iphe3fa5df43/ios), the iPhone 11 and iPhone SE (2nd generation) are listed as supported devices. I just want to double-check and confirm: since they meet the criteria mentioned in the video, do these features actually run without any performance issues or limitations on the iPhone 11 and iPhone SE (2nd gen)? I want to make sure I understand the exact hardware capabilities before proceeding with development. Thanks for your help!

We are developing a video streaming app that uses AVContentKeySession with FairPlay Streaming. Our implementation supports both online playback (non-persistable keys) and offline playback (persistable keys). We have observed the following behavior: Once a content key has been obtained for a given Content Key ID, AVContentKeySession does not trigger contentKeySession(_:didProvide:) again for that same Key ID We also attempted to explicitly call processContentKeyRequest(withIdentifier:initializationData:options:) on the session to force a new key request for the same identifier, but this did not result in the delegate callback being fired again. The session appears to consider the key already resolved and silently ignores the request. This means that if a user first plays content online (receiving a non-persistable key), and later wants to download the same content for offline use (requiring a persistable key), the delegate callback is not fired again, and we have no opportunity to request a persistable key. Questions Is this the expected behavior? Specifically, is it by design that AVContentKeySession caches the key for a given Key ID and does not re-request it — even when processContentKeyRequest(withIdentifier:) is explicitly called? Should we use distinct Content Key IDs for persistable vs. non-persistable keys? For example, if the same piece of content can be played both online and offline, is the recommended approach to have the server provide different EXT-X-KEY URIs (and thus different key identifiers) for the streaming and download variants? Is there a supported way to force a fresh key request for a Key ID that has already been resolved — for example, to upgrade from a non-persistable to a persistable key? Environment iOS 18+ AVContentKeySession(keySystem: .fairPlayStreaming) Any guidance on the recommended approach for supporting both streaming and offline playback for the same content would be greatly appreciated.

I am using iPad Pro M4 device to apply exposure point to the camera. While converting layerPointConverted from 0 -1 range to device size point it is giving wrong value. But if same code is used for other iPad like Gen2, it gives proper value. In both cases video gravity used is resizeAspectFill. I tried using true depth camera for M4 device but it does not work.

Hello, I used AVPlayer in my project to play network movie. Most movie could play normally, but I found the sound will disappear sometimes if I play specified 4K video network stream. The video will continue playing but audio stops after video is played for a while. If I pause player and then resume, the sound will be back but disappeared again after several seconds Check AVPlayerItem status: isPlaybackLikelyToKeepUp` == true isPlaybackBufferEmpty` = false player.volume > 0 According the value above, it seems not cause by empty playback buffer or volume issue. I am so confused for this situation. Movie information Video Format : AVC Format/Info : Advanced Video Codec Format profile : High L5.1 Codec ID : avc1 Codec ID/Info : Advanced Video Coding Bit rate mode : Variable Bit rate : 100.0 Mb/s Width : 3 840 pixels Height : 2 160 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 29.970 (30000/1001) FPS Audio Format : AAC LC Format/Info : Advanced Audio Codec Low Complexity Codec ID : mp4a-40-2 Duration : 5 min 19 s Bit rate mode : Constant Bit rate : 192 kb/s Nominal bit rate : 48.0 kb/s Channel(s) : 2 channels Channel layout : L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 SPF) Does anyone know if AVPlayer has this limitations when playing high-bitrate movie streams, and are there any solutions?

I'm developing an audio player app that uses AVAudio​File to read PCM data from various formats. I'm experiencing severe performance issues when seeking in FLAC, while other compressed formats (M4A/AAC) work correctly. I don't intend to use them in my app, but I also tested mp3 files just by curiosity and they also have this issue. Environment: macOS 26 (Tahoe) Xcode 26.3 Apple Silicon (M1) The issue: After setting AVAudio​File​.frame​Position to a position mid-file, the subsequent call to AVAudio​File​.read(into​:frame​Count:) blocks for an unreasonable amount of time for FLAC and MP3 files. The delay scales linearly with the seek target, seeking near the beginning is fast, seeking toward the end is proportionally slower, which suggests the decoder is decoding linearly from the beginning of the file rather than using any seek index. (My app deals with “images” of Audio CDs ripped as a single long audio file.) The issue is particularly severe when reading files from an SMB network share (server on Ethernet, client on Wi-Fi with the access point ~2 meters away in line of sight). Quick Benchmark results: I tested with the same 75-minute audio content (16-bit/44.1 kHz stereo, 200,502,708 frames) encoded in five formats, seeking to the midpoint. Over SMB (Local Network, Server on Ethernet, Client on WiFi): Format | Seek + Read Time ----------|------------------ WAV | 0.007 s AIFF | 0.009 s Apple | 0.015 s Lossless | MP3 | 9.2 s FLAC | 30.2 s Locally (MacBook Air M1 SSD) : Format | Seek + Read Time ----------|------------------ WAV | 0.0005 s AIFF | 0.0004 s Apple | 0.0011 s Lossless | MP3 | 0.1958 s FLAC | 0.7528 s WAV, AIFF, and M4A all seek virtually instantly (< 15 ms). MP3 and FLAC exhibit linear-time behavior, with FLAC being the worst affected. Note that M4A (AAC) is also a compressed format that requires decoding after seeking, yet it completes in 15 ms. This rules out any inherent limitation of compressed formats, the MP4 container's packet index (stts/stco) is clearly being used for fast random access. Both MP3 (Xing/LAME TOC) and FLAC (SEEKTABLE metadata block) have their own seek mechanisms that should provide similar performance. Minimal CLI tool to reproduce: import Foundation guard CommandLine.arguments.count > 1 else { print("Usage: FLACSpeed <audio-file-path>") exit(1) } let path = CommandLine.arguments[1] let fileURL = URL(fileURLWithPath: path) do { let file = try AVAudioFile(forReading: fileURL) let format = file.processingFormat let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: 8192)! let totalFrames = file.length let seekTarget = totalFrames / 2 print("File: \(fileURL.lastPathComponent)") print("Format: \(format)") print("Total frames: \(totalFrames)") print("Seeking to frame: \(seekTarget)") file.framePosition = seekTarget let start = CFAbsoluteTimeGetCurrent() try file.read(into: buffer, frameCount: 8192) let elapsed = CFAbsoluteTimeGetCurrent() - start print("Read after seek took \(elapsed) seconds") } catch { print("Error: \(error.localizedDescription)") exit(1) } Expected behavior: AVAudio​File​.read(into​:frame​Count:) after setting frame​Position should use the available seek mechanisms in FLAC and MP3 files for fast random access, as it already does for M4A (AAC). Even accounting for the fact that seek tables provide approximate (not sample-precise) positioning, the "jump to nearest index point + decode forward" approach should complete in milliseconds, not seconds. Workaround: For FLAC, I've worked around this by using libFLAC directly, which provides instant seeking via FLAC__stream​_decoder​_seek​_absolute(). libFLAC Performance: For comparison, libFLAC's FLAC__stream​_decoder​_seek​_absolute() performs the same seek + read on the same FLAC file in around 0.015, using the FLAC seek table to jump to the nearest preceding seek point, then decoding forward a small number of frames to the exact target sample.

AVPictureInPictureController with AVSampleBufferDisplayLayer: Video not scaled in PiP window on macOS Platform: macOS 26.4 (Tahoe) Framework: AVKit / AVFoundation Xcode: 26.4 Summary When using AVPictureInPictureController with ContentSource(sampleBufferDisplayLayer:playbackDelegate:) on macOS, the video content in the PiP window is not scaled to fit — it renders at 1:1 pixel resolution, showing only the bottom-left portion of the video (zoomed/cropped). The same code works correctly on iOS. Setup let displayLayer = AVSampleBufferDisplayLayer() displayLayer.videoGravity = .resizeAspect // Host displayLayer as a sublayer of an NSView, enqueue CMSampleBuffers let source = AVPictureInPictureController.ContentSource( sampleBufferDisplayLayer: displayLayer, playbackDelegate: self ) let pip = AVPictureInPictureController(contentSource: source) pip.delegate = self The source display layer is 1280×720, matching the video stream resolution. PiP starts successfully — isPictureInPicturePossible is true, the PiP button works, and the PIPPanel window appears. However, the video in the PiP window (~480×270) shows only the bottom-left 480×270 pixels of the 1280×720 content, rather than scaling the full frame to fit. Investigation Inspecting the PiP window hierarchy reveals: PIPPanel (480×270) └─ AVPictureInPictureSampleBufferDisplayLayerView └─ AVPictureInPictureSampleBufferDisplayLayerHostView (layer = CALayerHost) └─ AVPictureInPictureCALayerHostView The CALayerHost mirrors the source AVSampleBufferDisplayLayer at 1:1 pixel resolution. Unlike AVPlayerLayer-based PiP (which works correctly on macOS), the sample buffer display layer path does not apply any scaling transform to the mirrored content. On iOS, PiP with AVSampleBufferDisplayLayer works correctly because the system reparents the layer into the PiP window, so standard layer scaling applies. On macOS, the system uses CALayerHost mirroring instead, and the scaling step is missing. What I tried (none fix the issue) Setting autoresizingMask on all PiP internal subviews — views resize correctly, but CALayerHost content remains at 1:1 pixel scale Applying CATransform3DMakeScale on the CALayerHost layer — creates a black rectangle artifact; the mirrored content does not transform Setting CALayerHost.bounds to the source layer size — no effect on rendering Reparenting the internal AVPictureInPictureCALayerHostView out of the host view — video disappears entirely Hiding the CALayerHost — PiP window goes white (confirming it is the sole video renderer) Resizing the source AVSampleBufferDisplayLayer to match the PiP window size — partially works (1:1 mirror of a smaller source fits), but causes visible lag during resize, affects the main window's "This video is playing in Picture in Picture" placeholder, and didTransitionToRenderSize stops being called after the initial resize Expected behavior The video content should be scaled to fit the PiP window, respecting the display layer's videoGravity setting (.resizeAspect), consistent with: iOS PiP with AVSampleBufferDisplayLayer (works correctly) macOS PiP with AVPlayerLayer (works correctly) Environment macOS 26.4 (Tahoe) Xcode 26.4 Apple Silicon (M-series) Retina display (contentsScale = 2.0) Video: H.264 1280×720, hardware decoded via VTDecompressionSession, enqueued as CMSampleBuffer

Hi, I'm investigating whether 18MP photo capture from the front camera on iPhone 17 Pro is available to third-party apps using AVFoundation. I first inspected all available AVCaptureDevice formats, but I could not find any format corresponding to ~18MP resolution (e.g., around 4896×3672). for format in device.formats { let desc = format.formatDescription let dims = CMVideoFormatDescriptionGetDimensions(desc) print("Format: (dims.width) x (dims.height)") } All reported formats appear to be limited to resolutions such as 4032×3024 (12MP) or below. Question: Is 18MP front camera capture actually available to third-party apps via AVFoundation on iPhone 17?

Hello, I've been very familiar with the UVC Support in iPadOS ever since it launched in iOS 17. There are a number of people that use the software I've developed built around UVC and there are often queries about 8-Bit vs. 10-Bit. My understanding is that the newest UVC Spec is 1.5 which was standardised in 2012 and almost every UVC Capture Card runs at 8-Bit. The only 10-Bit Capture Card that is on my radar is the AJA U-Tap SDI, however it looks like this is 10-Bit up until the UVC Part where the 10-Bit Input is downsampled to 8-Bit. Though I have read in certain places that it works as a 10-Bit Capture Card on macOS but not on iPadOS. I was just wondering if 10-Bit via UVC is even possible on iPadOS? If there was indeed a true 10-Bit Source being passed into an iPad, would iPadOS allow it or would it be downsampled by AVFoundation so it can show up as a valid external video input? All USB Capture Cards that I have encountered use one of the following formats: kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange kCVPixelFormatType_420YpCbCr8BiPlanarFullRange kCVPixelFormatType_32BGRA So if a UVC Device delivered a 10-Bit Format, would that be accessible by iPadOS or would it fallback to these 8-Bit Formats by default? Thanks!

Hi everyone, I've encountered a rare and strange crash in my app that I can't consistently reproduce. The crash seems to occur deep within Apple's internal frameworks, and I can't pinpoint which line of my own code is causing it. Here's the crash stack trace: #44 AXSpeech SIGSEGV SEGV_ACCERR 0 CoreFoundation ___CFCheckCFInfoPACSignature + 4 1 CoreFoundation _CFRunLoopSourceSignal + 28 2 Foundation _performQueueDequeue + 492 3 Foundation ___NSThreadPerformPerform + 88 4 CoreFoundation ___CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28 5 CoreFoundation ___CFRunLoopDoSource0 + 176 6 CoreFoundation ___CFRunLoopDoSources0 + 340 7 CoreFoundation ___CFRunLoopRun + 828 8 CoreFoundation _CFRunLoopRunSpecific + 608 9 Foundation -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 212 10 TextToSpeech _TTSCFAttributedStringCreateStringByBracketingAttributeWithString + 776 11 Foundation ___NSThread__start__ + 732 12 libsystem_pthread.dylib __pthread_start + 136 Sometimes, instead of line 10 referencing _TTSCFAttributedStringCreateStringByBracketingAttributeWithString, it shows: 10 TextToSpeech LogWarning(char const*, ...) + 7288 Has anyone experienced a similar issue or know what might be triggering this crash? Any guidance on how to investigate or resolve this would be greatly appreciated. Thank you!

Hello there, Our application has HLS VOD download option. Users can download VOD which has DRM protection and watch content when device is offline. We use aggregateAssetDownloadTask to download HLS VOD. We want to resume download after Wifi/LTE change but it does not resume. Download is starting from beginning. We use some token algorithms to start download. That's why, our playlist url and chunks urls may change. But playlist and chunk urls' content is unique. If user start to download via Wifi and changed to LTE. Download request responds 403 Forbidden because of some token algorithms after some time func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) AVAssetDownloadDelegate function triggered by system. If we resume it does not resume at this point. It is starting from beginning if we start new download process for same content. Is there any way to resume unfinished HLS Download processes? Thanks

I'm getting Crashlytics crashes from some my users, deep in the Apple code: Crashed: AXSpeech EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x00000007ec54b360 0 libobjc.A.dylib 0x3c9c objc_retain_x8 + 16 1 AudioToolboxCore 0x99580 auoop::RenderPipeUser::~RenderPipeUser() + 112 2 AudioToolboxCore 0xe6090 -[AUAudioUnit_XPC internalDeallocateRenderResources] + 92 3 AVFAudio 0x90a0 AUInterfaceBaseV3::Uninitialize() + 60 4 AVFAudio 0x4cbe0 AVAudioEngineGraph::PerformCommand(AUGraphNodeBaseV3&, AVAudioEngineGraph::ENodeCommand, void*, unsigned int) const + 768 5 AVFAudio 0x56b0c AVAudioEngineGraph::_Uninitialize(NSError**) + 132 6 AVFAudio 0x7834 AVAudioEngineImpl::Stop(NSError**) + 388 7 AVFAudio 0x636c -[AVAudioEngine dealloc] + 52 8 TextToSpeech 0x30674 _TTSNameForVoiceInformation + 20864 9 libobjc.A.dylib 0x20a4 object_cxxDestructFromClass(objc_object*, objc_class*) + 116 10 libobjc.A.dylib 0x6e00 objc_destructInstance + 80 11 libobjc.A.dylib 0x104fc _objc_rootDealloc + 80 12 TextToSpeech 0x2d2f4 _TTSNameForVoiceInformation + 7680 13 TextToSpeech 0x496c TTSVocalizerCopyURLForFallbackResource + 8540 14 TextToSpeech 0x26094 TTSSpeechUnitTestingMode + 5548 15 libAXSpeechManager.dylib 0x108b0 -[AXSpeechManager .cxx_destruct] + 192 16 libobjc.A.dylib 0x20a4 object_cxxDestructFromClass(objc_object*, objc_class*) + 116 17 libobjc.A.dylib 0x6e00 objc_destructInstance + 80 18 libobjc.A.dylib 0x104fc _objc_rootDealloc + 80 19 libAXSpeechManager.dylib 0x5298 -[AXSpeechManager dealloc] + 268 20 Foundation 0x3b8a4 __NSThreadPerformPerform + 272 21 CoreFoundation 0xd3208 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28 22 CoreFoundation 0xdf864 __CFRunLoopDoSource0 + 176 23 CoreFoundation 0x646c8 __CFRunLoopDoSources0 + 244 24 CoreFoundation 0x7a1c4 __CFRunLoopRun + 828 25 CoreFoundation 0x7f4dc CFRunLoopRunSpecific + 612 26 Foundation 0x420c4 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 212 27 libAXSpeechManager.dylib 0x13390 -[AXSpeechThread main] + 552 28 Foundation 0x5b634 __NSThread__start__ + 716 29 libsystem_pthread.dylib 0x16b8 _pthread_start + 148 30 libsystem_pthread.dylib 0xb88 thread_start + 8 It's most likely related to my use of AVSpeechSynthesizer. I do change some of the utterance fields, including the voice that's being used (which is set to a value from speechVoices()). UtilAudioIos_tts = AVSpeechSynthesizer() let utterance = AVSpeechUtterance utterance.voice = AVSpeechSynthesisVoice(identifier: voice.voiceCode) utterance.volume = volume utterance.pitchMultiplier = pitch utterance.rate = rate UtilAudioIos_tts!.speak(utterance) By coincidence or not, the following sometimes appears in the device log: 2023-05-30 20:35:29.948078+0100 <appname>[466:12882] [catalog] Unable to list voice folder and also, sometimes: 2023-05-30 20:37:35.345933+0100 <appname>[466:13298] [catalog] Query for com.apple.MobileAsset.VoiceServices.VoiceResources failed: 2 2023-05-30 20:37:35.360854+0100 rehearserfree[466:13433] [AXTTSCommon] MauiVocalizer: 11006 (Can't compile rule): regularExpression=\Oviedo(?=, (\x1b\\pause=\d+\\)?Florida)\b, message=unrecognized character follows \, characterPosition=1 2023-05-30 20:37:35.363163+0100 <appname>[466:13433] [AXTTSCommon] MauiVocalizer: 16038 (Resource load failed): component=ttt/re, uri=, contentType=application/x-vocalizer-rettt+text, lhError=88602000 2023-05-30 20:37:35.363182+0100 <appname>[466:13433] [AXTTSCommon] Error loading rules: 2147483648 All of these crashes have been on the various versions of iOS 16. Edit: I can't reproduce the crash myself - it's just some (not all) app users. The log entries above appear locally on my device (with no crash) but I can't see the logs of the users who have the crashes. Any idea what this might be caused by, or how to go about tracking the problem down?

Hello, I’m experiencing a severe performance degradation when running CoreML models on a live AVFoundation video feed compared to offline or synthetic inference. This happens across multiple models I've converted (including SCI, RTMPose, and RTMW) and affects multiple devices. The Environment OS: macOS 26.3, iOS 26.3, iPadOS 26.3 Hardware: Mac14,6 (M2 Max), iPad Pro 11 M1, iPhone 13 mini Compute Units: cpuAndNeuralEngine The Numbers When testing my SCI_output_image_int8.mlpackage model, the inference timings are drastically different: Synthetic/Offline Inference: ~1.34 ms Live Camera Inference: ~15.96 ms Preprocessing is completely ruled out as the bottleneck. My profiling shows total preprocessing (nearest-neighbor resize + feature provider creation) takes only ~0.4 ms in camera mode. Furthermore, no frames are being dropped. What I've Tried I am building a latency-critical app and have implemented almost every recommended optimization to try and fix this, but the camera-feed penalty remains: Matched the AVFoundation camera output format exactly to the model input (640x480 at 30/60fps). Used IOSurface-backed pixel buffers for everything (camera output, synthetic buffer, and resize buffer). Enabled outputBackings. Loaded the model once and reused it for all predictions. Configured MLModelConfiguration with reshapeFrequency = .frequent and specializationStrategy = .fastPrediction. Wrapped inference in ProcessInfo.processInfo.beginActivity(options: .latencyCritical, reason: "CoreML_Inference"). Set DispatchQueue to qos: .userInteractive. Disabled the idle timer and enabled iOS Game Mode. Exported models using coremltools 9.0 (deployment target iOS 26) with ImageType inputs/outputs and INT8 quantization. Reproduction To completely rule out UI or rendering overhead, I wrote a standalone Swift CLI script that isolates the AVFoundation and CoreML pipeline. The script clearly demonstrates the ~15ms latency on live camera frames versus the ~1ms latency on synthetic buffers. (I have attached camera_coreml_benchmark.swift and coreml model (very light low light enghancement model) to this repo on github https://github.com/pzoltowski/apple-coreml-camera-latency-repro). My Question: Is this massive overhead expected behavior for AVFoundation + Core ML on live feeds, or is this a framework/runtime bug? If expected, what is the Apple-recommended pattern to bypass this camera-only inference slowdown? One think found interesting when running in debug model was faster (not as fast as in performance benchmark but faster than 16ms. Also somehow if I did some dummy calculation on on different DispatchQueue also seems like model got slightly faster. So maybe its related to ANE Power State issues (Jitter/SoC Wake) and going to fast to sleep and taking a long time to wakeup? Doing dummy calculation in background thought is probably not a solution. Thanks in advance for any insights!

Hello, I am wondering if it is possible to have audio from my AirPods be sent to my speech to text service and at the same time have the built in mic audio input be sent to recording a video? I ask because I want my users to be able to say "CAPTURE" and I start recording a video (with audio from the built in mic) and then when the user says "STOP" I stop the recording.

My app uses the AVFoundation to pronounce some words. Running the app from Xcode, either to a simulator or device, I frequently get this crash at start-up: AXSpeech (13): EXC_BAD_ACCESS (code=EXC_I386_GPFLT). It seems to occur randomly, maybe 20%-30% of the time I launch the app. When it does not crash, using audio works as expected. When launched from the device, it never crashes (so far, at least). Here's the code that outputs speech: Declared at the top level of the View struct: @State var synth = AVSpeechSynthesizer() In the View, as part of a Button's action closure: let utterance = AVSpeechUtterance(string: answer) utterance.voice = AVSpeechSynthesisVoice(language: "en_US") synth.speak(utterance) Any idea on how to stop this? It's annoying having to launch the app multiple times to test on a simulator or device.