Please include the line below in follow-up emails for this request.
Case-ID: 11089799
When using AVSpeechUtterance and setting it to play in Mandarin, if Siri is set to Cantonese on iOS 18, it will be played in Cantonese. There is no such issue on iOS 17 and 16.
1.let utterance = AVSpeechUtterance(string: textView.text)
let voice = AVSpeechSynthesisVoice(language: "zh-CN")
utterance.voice = voice
2.In the phone settings, Siri is set to Cantonese
Explore the integration of media technologies within your app. Discuss working with audio, video, camera, and other media functionalities.
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Context:
I am currently developing an app using the Push-to-Talk (PTT) framework. I have reviewed both the PTT framework documentation and the CallKit demo project to better understand how to properly manage audio session activation and AVAudioEngine setup.
I am not activating the audio session manually. The audio session configuration is handled in the incomingPushResult or didBeginTransmitting callbacks from the PTChannelManagerDelegate.
I am using a single AVAudioEngine instance for both input and playback. The engine is started in the didActivate callback from the PTChannelManagerDelegate. When I receive a push in full duplex mode, I set the active participant to the user who is speaking.
Issue
When I attempt to talk while the other participant is already speaking, my input tap on the input node takes a few seconds to return valid PCM audio data. Initially, it returns an empty PCM audio block.
Details:
The audio session is already active and configured with .playAndRecord.
The input tap is already installed when the engine is started.
When I talk from a neutral state (no one is speaking), the system plays the standard "microphone activation" tone, which covers this initial delay. However, this does not happen when I am already receiving audio.
Assumptions / Current Setup
Because the audio session is active in play and record, I assumed that microphone input would be available immediately, even while receiving audio.
However, there seems to be a delay before valid input is delivered to the tap, only occurring when switching from a receive state to simultaneously talking.
Questions
Is this expected behavior when using the PTT framework in full duplex mode with a shared AVAudioEngine?
Should I be restarting or reconfiguring the engine or audio session when beginning to talk while receiving audio?
Is there a recommended pattern for managing microphone readiness in this scenario to avoid the initial empty PCM buffer?
Would using separate engines for input and output improve responsiveness?
I would like to confirm the correct approach to handling simultaneous talk and receive in full duplex mode using PTT framework and AVAudioEngine. Specifically, I need guidance on ensuring the microphone is ready to capture audio immediately without the delay seen in my current implementation.
Relevant Code Snippets
Engine Setup
func setup() {
let input = audioEngine.inputNode
do {
try input.setVoiceProcessingEnabled(true)
} catch {
print("Could not enable voice processing \(error)")
return
}
input.isVoiceProcessingAGCEnabled = false
let output = audioEngine.outputNode
let mainMixer = audioEngine.mainMixerNode
audioEngine.connect(pttPlayerNode, to: mainMixer, format: outputFormat)
audioEngine.connect(beepNode, to: mainMixer, format: outputFormat)
audioEngine.connect(mainMixer, to: output, format: outputFormat)
// Initialize converters
converter = AVAudioConverter(from: inputFormat, to: outputFormat)!
f32ToInt16Converter = AVAudioConverter(from: outputFormat, to: inputFormat)!
audioEngine.prepare()
}
Input Tap Installation
func installTap() {
guard AudioHandler.shared.checkMicrophonePermission() else {
print("Microphone not granted for recording")
return
}
guard !isInputTapped else {
print("[AudioEngine] Input is already tapped!")
return
}
let input = audioEngine.inputNode
let microphoneFormat = input.inputFormat(forBus: 0)
let microphoneDownsampler = AVAudioConverter(from: microphoneFormat, to: outputFormat)!
let desiredFormat = outputFormat
let inputFramesNeeded = AVAudioFrameCount((Double(OpusCodec.DECODED_PACKET_NUM_SAMPLES) * microphoneFormat.sampleRate) / desiredFormat.sampleRate)
input.installTap(onBus: 0, bufferSize: inputFramesNeeded, format: input.inputFormat(forBus: 0)) { [weak self] buffer, when in
guard let self = self else { return }
// Output buffer: 1920 frames at 16kHz
guard let outputBuffer = AVAudioPCMBuffer(pcmFormat: desiredFormat, frameCapacity: AVAudioFrameCount(OpusCodec.DECODED_PACKET_NUM_SAMPLES)) else { return }
outputBuffer.frameLength = outputBuffer.frameCapacity
let inputBlock: AVAudioConverterInputBlock = { inNumPackets, outStatus in
outStatus.pointee = .haveData
return buffer
}
var error: NSError?
let converterResult = microphoneDownsampler.convert(to: outputBuffer, error: &error, withInputFrom: inputBlock)
if converterResult != .haveData {
DebugLogger.shared.print("Downsample error \(converterResult)")
} else {
self.handleDownsampledBuffer(outputBuffer)
}
}
isInputTapped = true
}
Our streaming app uses FairPlay-protected video streams, which previously worked fine when using AVAssetResourceLoaderDelegate to provide CKCs.
Recently, we migrated to AVContentKeySession, and while everything works as expected during regular playback, we encountered an issue with AirPlay.
Our CKC has a 120-second expiry, so we renew it by calling renewExpiringResponseData..
This trigger the didProvideRenewingContentKeyRequest delegate and we respond with updated CKC.
However, when streaming via AirPlay, both video and audio freeze exactly after 120 seconds.
To validate the issue, I tested with AVAssetResourceLoaderDelegate and found that I can reproduce the same freeze if I do not renew the key. This suggests that AirPlay is not accepting the renewed CKC when using AVContentKeySession.
Additional Details:
This issue occurs across different iOS versions and various AirPlay devices.
The same content plays without issues when played directly on the device.
The renewal process is successful, and segments continue to load, but playback remains frozen.
Tried renewing the CKC bit early (100s).
I also tried setting player.usesExternalPlaybackWhileExternalScreenIsActive = true, but the issue persists.
We don't use persistentKey.
Is there anything else that needs to be considered for proper key renewal when AirPlaying?
Any help on how to fix this or confirmation if this is a known issue would be greatly appreciated.
Hello,
I have been running into issues with setting nowPlayingInfo information, specifically updating information for CarPlay and the CPNowPlayingTemplate.
When I start playback for an item, I see lock screen information update as expected, along with the CarPlay now playing information.
However, the playing items are books with collections of tracks. When I select a new track(chapter) within the book, I set the MPMediaItemPropertyTitle to the new chapter name. This change is reflected correctly on the lock screen, but almost never appears correctly on the CarPlay CPNowPlayingTemplate. The previous chapter title remains set and never updates.
I see "Application exceeded audio metadata throttle limit." in the debug console fairly frequently.
From that a I figured that I need to minimize updates to the nowPlayingInfo dictionary. What I did:
I store the metadata dictionary in a local dictionary and only set values in the main nowPlayingInfo dictionary when they are different from the current value.
I kick off the nowPlayingInfo update via a task that initially sleeps for around 2 seconds (not a final value, just for my current testing). If a previous Task is active, it gets cancelled, so that only one update can happen within that time window.
Neither of these things have been sufficient. I can switch between different titles entirely and the information updates (including cover art).
But when I switch chapters within a title, the MPMediaItemPropertyTitle continues to get dropped. I know the value is getting set, because it updates on the lock screen correctly.
In total, I have 12 keys I update for info, though with the above changes, usually 2-4 of them actually get updated with high frequency.
I am running out of ideas to satisfy the throttling thresholds to accurately display metadata. I could use some advice.
Thanks.
I occasionally receive reports from users that photo import from the Photos library gets stuck and the progress appears to stop indefinitely.
I’m using the following APIs:
func fetchAsset(_ asset: PHAsset) {
let options = PHImageRequestOptions()
options.deliveryMode = .highQualityFormat
options.resizeMode = .exact
options.isSynchronous = false
options.isNetworkAccessAllowed = true
options.progressHandler = { (progress, error, stop, info) in
// 🚨 never called
}
let requestId = PHImageManager.default().requestImageDataAndOrientation(
for: asset,
options: options
) { data, _, _, info in
// 🚨 never called
}
}
Due to repeated reports, I added detailed logs inside the callback closures. Based on the logs, it looks like the request keeps waiting without any callbacks being invoked — neither the progressHandler nor the completion block of requestImageDataAndOrientation is called.
This happens not only with the PHImageManager approach, but also when using PHAsset with PHContentEditingInputRequestOptions — the completion callback is not invoked as well.
func fetchAssetByContentEditingInput(_ asset: PHAsset) {
let options = PHContentEditingInputRequestOptions()
options.isNetworkAccessAllowed = true
asset.requestContentEditingInput(with: nil) { contentEditingInput, info in
// 🚨 never called
}
}
I suspect this is related to iCloud Photos.
Here is what I confirmed from affected users:
Using the native picker (My app also provides the native picker as an alternative option for attaching photos), iCloud download proceeds normally and the photo can be attached. However, using the PHImageManager-based approach in my app, the same photo cannot be attached.
Even after verifying that the photo has been fully downloaded from iCloud (e.g., by trying “Export Unmodified Originals” in the Photos app as described here: https://support.apple.com/en-us/111762, and confirming the iCloud download progress completed), the callback is still not invoked for that asset.
Detailed flow for (1):
I asked the user to attach the problematic photo (the one where callbacks never fire) using the native photo picker (UIImagePickerController).
The UI showed “Downloading from iCloud” progress.
The progress advanced and the photo was attached successfully.
Then I asked the user to attach the same photo again using my custom photo picker (which uses the PHImageManager APIs mentioned above).
The progress did not advance (No callbacks were invoked).
The operation waited indefinitely and never completed.
Workaround / current behavior:
If I ask users to reboot the device and try again, about 6 out of 10 users can attach successfully afterward.
The remaining ~4 out of 10 users still cannot attach even after rebooting.
For users who are not fixed immediately after reboot, it seems to resolve naturally after some time.
I’ve seen similar reports elsewhere, so I’m wondering if Apple is already aware of an internal issue related to this. If there is any known information, guidance, or recommended workaround, I would appreciate it.
I also logged the properties of affected PHAssets (metadata) when the issue occurs, and I can share them below if that helps troubleshooting:
[size=3.91MB] [PHAssetMediaSubtype(rawValue: 528)+DepthEffect | userLibrary | (4284x5712) | adjusted=true]
[size=3.91MB] [PHAssetMediaSubtype(rawValue: 528)+DepthEffect | userLibrary | (4284x5712) | adjusted=true]
[size=2.72MB] [PHAssetMediaSubtype(rawValue: 16)+DepthEffect | userLibrary | (3024x4032) | adjusted=true]
[size=2.72MB] [PHAssetMediaSubtype(rawValue: 16)+DepthEffect | userLibrary | (3024x4032) | adjusted=true]
[size=2.49MB] [PHAssetMediaSubtype(rawValue: 16)+DepthEffect | userLibrary | (3024x4032) | adjusted=true]
[size=2.49MB] [PHAssetMediaSubtype(rawValue: 16)+DepthEffect | userLibrary | (3024x4032) | adjusted=true]
Hello Apple team and developer community,
I am preparing a visionOS app for a fair environment, where we want to automatically stream the current experience to a nearby monitor via AirPlay, without requiring guests or staff to manually interact with the Control Center or AirPlay pickers all the time.
The goal is to provide a smooth, frictionless setup so attendees can focus on the demo, not the configuration.
Feature Request:
A supported API or method to programmatically start/stop AirPlay video streaming (mirroring or external playback) from within a visionOS app, allowing the current experience to be instantly displayed on an external monitor or Apple TV for the audience.
Context & Rationale:
In a trade fair or exhibition setting, rapid guest turnaround and minimal staff intervention are crucial. Having to manually guide each visitor through AirPlay setup is impractical.
As I understood, AVRoutePickerView can be used for this on iOS/macOS, but this is not available in visionOS. Enabling similar automated streaming on visionOS would make the device far more suitable for live demos and public showcases.
Questions:
Are there any supported workarounds or best practices for enabling automated screen streaming or AirPlay initiation on visionOS in public demo environments that I missed?
Is Apple considering adding programmatic AirPlay control or accessibility features to support such use cases in future visionOS releases?
Thank you for considering this request! If there are recommended patterns, entitlements, or accessibility solutions we could explore for trade fair scenarios, your guidance would be greatly appreciated.
Best regards,
Julian Zürn - IPI, HS Kempten
Hello,
Does anyone have a recipe on how to raycast VNFaceLandmarkRegion2D points obtained from a frame's capturedImage?
More specifically, how to construct the "from" parameter of the frame's raycastQuery from a VNFaceLandmarkRegion2D point?
Do the points need to be flipped vertically? Is there any other transformation that needs to be performed on the points prior to passing them to raycastQuery?
When building an application that can be built on iOS using macCatalyst, a link error like the one below will occur.
Undefined symbol: OBJC_CLASS$_AVPlayerViewController
The AVPlayerViewController documentation seems to support macCatalyst, but what is the reality?
[AVPlayerViewController](https://developer.apple.com/documentation/avkit/avplayerviewcontroller? language=objc)
Each version of the environment is as follows.
Xcode 16.2
macOS deployment target: macOS 10.15
iOS deployment target: iOS 13.0
Thank you for your support.
Topic:
Media Technologies
SubTopic:
General
I'm using an AVCaptureSession to send video and audio samples to an AVAssetWriter. When I play back the resultant video, sometimes there is a significant lag between the audio compared with the video, so they're just not in sync. But sometimes they are, with the same code.
If I look at the very first presentation time stamps of the buffers being sent to the delegate, via
func captureOutput(_: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection)
I see something like this:
Adding audio samples for pts time 227711.0855328798,
Adding video samples for pts time 227710.778785374
That is, the clock for audio vs video is behind: the first audio sample I receive is at 11.08 something, while the video video sample is earlier in time, at 10.778 something. The times are the presentation time stamps of the buffer, and the outputPresentationTimeStamp is the exact same number.
It feels like "video" vs the "audio" clock are just mismatched.
This doesn't always happen: sometimes they're synced. Sometimes they're not.
Any ideas? The device I'm recording is a webcam, on iPadOS, connected via the usb-c port.
If the app is launched from LockedCameraCapture and if the settings button is tapped, I need to launch the main app.
CameraViewController:
func settingsButtonTapped() {
#if isLockedCameraCaptureExtension
//App is launched from Lock Screen
//Launch main app here...
#else
//App is launched from Home Screen
self.showSettings(animated: true)
#endif
}
In this document:
https://developer.apple.com/documentation/lockedcameracapture/creating-a-camera-experience-for-the-lock-screen
Apple asks you to use:
func launchApp(with session: LockedCameraCaptureSession, info: String) {
Task {
do {
let activity = NSUserActivityTypeLockedCameraCapture
activity.userInfo = [UserInfoKey: info]
try await session.openApplication(for: activity)
} catch {
StatusManager.displayError("Unable to open app - \(error.localizedDescription)")
}
}
}
However, the documentation states that this should be placed within the extension code - LockedCameraCapture. If I do that, how can I call that all the way down from the main app's CameraViewController?
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:
Topic:
Media Technologies
SubTopic:
Video
Hi,
I’m building a PPG-based heart rate feature where the user places their finger over the rear telephoto camera. On iPhone 16 Pro Max, I'm explicitly selecting the telephoto lens like this:
videoDevice = AVCaptureDevice.default(.builtInTelephotoCamera, for: .video, position: .back)
And trying to lock it:
if #available(iOS 15.0, *),
device.activePrimaryConstituentDeviceSwitchingBehavior != .unsupported {
try? device.lockForConfiguration()
device.setPrimaryConstituentDeviceSwitchingBehavior(.locked, restrictedSwitchingBehaviorConditions: [])
device.unlockForConfiguration()
}
I also lock everything else to prevent dynamic changes:
try device.lockForConfiguration()
device.focusMode = .locked
device.exposureMode = .locked
device.whiteBalanceMode = .locked
device.videoZoomFactor = 1.0
device.automaticallyEnablesLowLightBoostWhenAvailable = false
device.automaticallyAdjustsVideoHDREnabled = false
device.unlockForConfiguration()
Despite this, the camera still switches to another lens, especially under different lighting, even though the user’s finger fully covers the lens.
Questions:
How can I completely prevent lens switching in this scenario?
Would using videoZoomFactor = 3.0 or 5.0 better enforce use of the telephoto lens?
Thanks!
Gal
hello, I'm using VideoTololbox VTFrameRateConversionConfiguration to perform frame interpolation: https://developer.apple.com/documentation/videotoolbox/vtframerateconversionconfiguration?language=objc ,when using 640x480 vidoe input, I got error:
Error ! Invalid configuration
[VEEspressoModel] build failure : flow_adaptation_feature_extractor_rev2.espresso.net. Configuration: landscape640x480
[EpsressoModel] Cannot load Net file flow_adaptation_feature_extractor_rev2.espresso.net. Configuration: landscape640x480
Error: failed to create FRCFlowAdaptationFeatureExtractor for usage 8
Failed to switch (0x12c40e140) [usage:8, 1/4 flow:0, adaptation layer:1, twoStage:0, revision:2, flow size (320x240)].
Could not init FlowAdaptation
initFlowAdaptationWithError fail
tried 2048x1080 is ok.
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
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.
I'm capturing video stream from GoPro camera (I demux UDP MPEG-TS packets) and create CMSampleBuffers from them, this works fine when I display them using CMSampleBufferLayer.
However when I dump them to disk using AVAssetWriter and then playback it with AVPlayer, AVPlayer has problems with scrubbing, it also cannot render previous frames, it needs to go back to key frames. Also thumbnails generated with AVAssetImageGenerator are mostly distorted and green, even though I set the requestedTimeToleranceAfter longer than the key frames frequency.
When I re-encode saved video once again with AVAssetExportSession and play it back then I can scrub the video just fine.
Is it because re-transcoding adds additional metadata to enable generating frames when rewinding the video and scrubbing?
If so is there a way to achieve it with AVAssetWriter without much time penalty? I need the dump/save operation to be very fast.
I also considered the following: Instead of de-muxing video and creating CMSampleBuffers, maybe I could directly dump the stream to disk and somehow add moov atoms with timing information. Would this approach work? If so where I can find information how to do it?
Thank you!
Hey,
There seems to be an inconsistency when capturing a photo using
QualityPrioritization.Quality on the iPhone 17 Pro Main wide Lens. If you zoom above "2x" the output image always has "-2.0ev" bias in the meta data and looks underexposued. This does not happen at zoom levels above 2, or if you set the QualityPrioritization to .Balanced.
See below:
with .Quality
with .Balanced
This does not happen on the other lenses.
I'm using a simple set up and it is consistent across JPEG and ProRAW capture. I have a demo project if that is useful.
Thanks,
Alex
I am trying to use SpeechTranscriber from Speech framework. Is it possible to use it on Simulator of iOS 26 (Mac OS Tahoe)? Function "supportedLocales" returns an empty array.
Hi,
While I don't normally use FairPlay,
I got this email that is so strangely worded I am wondering if it makes sense to people who do know it or if it has some typo or what.
You can only generate certificates for SDK 4, also SDK 4 is no longer supported?
(Also "will not expire" is imprecise phrasing, certificates presumably will expire, I think it meant to say are still valid / are not invalidated.)
Dear Apple Developer Team,
On iOS 26, the contents of PDF pages appear to be swapped.
Could you please advise if there is a workaround or a planned fix for this issue?
Steps to Reproduce:
Download the attached PDF on iOS 26.
Open the PDF in the Files app.
Tap the PDF to view it in Quick Look.
Navigate to page 5.
Expected Result:
The page number displayed at the bottom should be 5.
Actual Result:
The page number displayed at the bottom is 4.
Issue:
This is not limited to page 5—multiple page contents appear to be swapped.
I have also submitted feedback via Feedback Assistant (FB20743531) on October 20.
Best regards,
Yoshihito Suezawa