I'm able to get text to speech to audio file using the following code for iOS 12 iPhone 8 to create a car file:
audioFile = try AVAudioFile(
forWriting: saveToURL,
settings: pcmBuffer.format.settings,
commonFormat: .pcmFormatInt16,
interleaved: false)
where pcmBuffer.format.settings is:
[AVAudioFileTypeKey: kAudioFileMP3Type,
AVSampleRateKey: 48000,
AVEncoderBitRateKey: 128000,
AVNumberOfChannelsKey: 2,
AVFormatIDKey: kAudioFormatLinearPCM]
However, this code does not work when I run the app in iOS 18 on iPhone 13 Pro Max. The audio file is created, but it doesn't sound right. It has a lot of static and it seems the speech is very low pitch.
Can anyone give me a hint or an answer?
Explore the integration of media technologies within your app. Discuss working with audio, video, camera, and other media functionalities.
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I am using an AVAudioPlayer to play a "tick" sound once per second in a SwiftUI app.
When running the app on an iPhone 16 (18.2.1) the tick sounds increase in volume after a few seconds. This does not happen in the simulator nor on an iPhone SE 2020 (18.1.1).
Topic:
Media Technologies
SubTopic:
Audio
I'm developing a photo backup app.
To detect newly added or edited photos since the app launched, I keep a local dictionary in the format [localIdentifier: modification_date].
However, PHAsset.modificationDate is not reliable.
It often changes unexpectedly, possibly due to system operations like iCloud metadata updates.
Is there a more reliable way to detect whether a photo has been modified by user since the last app launch?
I'm thinking about using content hash instead, but I'm not sure how heavy this operation is in terms of performance.
Issue:
Under certain conditions, using CallKit does not automatically enable the microphone.
Steps to Reproduce:
1.Start an outgoing call, then the user manually mutes the audio.
2.Receive a native incoming call, end the current call, then answer the new incoming call.(This order is important.)
3.End the incoming call.
4.Start another outgoing call and observe the microphone; do not manually mute or unmute.
Actual Behavior:
The audio icon indicates that the audio is unmuted, but the microphone remains off, and the small yellow dot in the top status bar (which represents the microphone) does not appear.
Expected Behavior:
The microphone should be on, consistent with the audio icon display, and the small yellow dot should appear in the top status bar.
Device:
iPhone 16 pro & iPhone 15 pro, iOS 18.0+
Can it be reproduced using speakerbox(CallKit Demo)?
YES
Hello Apple Developer Community,
I am seeking clarification on the intended display behavior of HLS audio tracks within the iOS 26 (or current beta) native player, specifically concerning the NAME and LANGUAGE attributes of the EXT-X-MEDIA tag.
In our HLS manifests, we define alternative audio tracks using EXT-X-MEDIA tags, like so:
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio",LANGUAGE="ja",NAME="AUDIO-1",DEFAULT=YES,AUTOSELECT=YES,URI="audio_ja.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio",LANGUAGE="ja",NAME="AUDIO-2",URI="audio_en.m3u8"
Our observation is that when an audio track is selected and its name is displayed in the native iOS media controls (e.g., Control Center or within a full-screen video player's UI), the value specified in the NAME attribute ("AUDIO-1", "AUDIO-2") does not seem to be used. Instead, the display appears to derive from the LANGUAGE attribute ("ja", "en"), often showing the system's localized string for that language (e.g., "Japanese", "English").
We would like to understand the official or intended behavior regarding this.
Is it the expected behavior for the iOS native player to prioritize the LANGUAGE attribute (or its localized equivalent) over the NAME attribute for displaying the selected audio track's label?
If this is the intended design, what is the recommended best practice for developers who wish to present a custom, human-readable name for audio tracks (beyond the standard language name) in the native iOS UI?
Are there any specific AVPlayer properties or AVMediaSelectionOption considerations that would allow more granular control over this display, or is this entirely managed by the system based on the LANGUAGE attribute?
Any insights or official guidance on this behavior in iOS 26 (and potentially previous versions) would be greatly appreciated.
Thank you for your time and assistance.
When using AVSampleBufferDisplayLayer to play uncompressed H.264 and H.265 video with B-frames more than 7, frame drops occur. The more B-frames there are, the more noticeable the frame drops become, for example 15 bframes.
Use FFmpeg to transcode a video file with visible timestamps and frame numbers (x264 or x265 ):
ffmpeg -i test.mp4 -vf "drawtext=fontsize=45:text=%{pts} %{n}:y=400" -c:v libx264 -x264-params "bframes=15:b-adapt=0" -crf 30 -y x264_bf15.mp4
ffmpeg -i test.mp4 -vf "drawtext=fontsize=45:text=%{pts} %{n}:y=400" -c:v libx265 -x265-params "bframes=15:b-adapt=0" -crf 30 -y x265_bf15.mp4
Use the demo player from this repository to reproduce the issue: https://github.com/msfrms/CustomPlayer
frame drops can be observed. And following log can be found in devices console.
mediaserverd <<<< IQ-CA >>>> piqca_gmstats_dump: FIQCA(0x1266f4000) recent frames: enqueued: 184, displayed: 138, dropped: 42, flushed: 0, evicted: 3, >16ms late: 2
PS. I was using iphone11 iOS14.6, to replay this issue.
May I ask why frame drops occur in this case?
Is there any configuration or API usage change that could help fix the frame drop issue?
Many thanks!
On an iPhone running iOS 26 beta 5, url(for: FilePath("subdir/asset.mov")) most always throws this error:
The URL for “subdir/asset.mov” couldn’t be retrieved: “asset.mov” couldn’t be copied to “subdir” because an item with the same name already exists.
Yet, contents(at: FilePath("subdir/asset.mov")) always returns Data for a playable AVMovie.
How can I avoid this url(for:) error?
The asset pack in question is downloaded. The error persists even after pack deletion, redownload, relaunch, and combinations of that.
// Assets repo root
subdir.aar
subdir/asset.mov
subdir/asset_thumb.heic
subdir/Manifest.json
// Manifest.json
{
"assetPackID": "subdir",
"downloadPolicy": {
"onDemand": {}
},
"fileSelectors": [
{
"directory": "subdir",
},
],
"platforms": [
"iOS",
"visionOS"
]
}
xcrun ba-package subdir/Manifest.json -o subdir.aar
xcrun ba-serve --host 192.168.0.10 -p 443 subdir.aar
Hello, I am trying to get the new iPhone 16 pro to achieve 4k 120fps encoding when we are getting the video feed from the default, wide angle camera on the back. We are using the apple API to capture the individual frames from the camera as they are processed and we get them in this callback:
// this is the main callback function to handle video frames captured
func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
We are then taking these frames as they come in and encoding them using VideoToolBox. After they are encoded, they are added to a ring buffer so we can access them after they have been encoded.
The problem is that when we are encoding these frames on an iPhone 16 Pro, we are only reaching 80-90fps instead of 120fps. We have removed as much processing as we can. We get some small attributes about the frame when it comes in, encode the frame, and then add it to our ring buffer.
I have attached a sample project that is broken down as much as possible to the basic task of encoding 4k 120fps footage. Inside the sample app, there is an fps and pps display showing how many frames we are encoding per second. FPS represents how many frames we are coming in per second from the camera, and PPS represents how many frames we are processing (encoding) per second.
Link to sample project: https://github.com/jake-fishtech/EncoderPerformance
Thanks you for any help or suggestions.
I’m currently developing an iOS metronome app using DispatchSourceTimer as the timer. The interval is set very small, around 50 milliseconds, and I’m using CFAbsoluteTimeGetCurrent to calculate the elapsed time to ensure the beat is played within a ±0.003-second margin.
The problem is that once the app goes to the background, the timing becomes unstable—it slows down noticeably, then recovers after 1–2 seconds.
When coming back to the foreground, it suddenly speeds up, and again, it takes 1–2 seconds to return to normal. It feels like the app is randomly “powering off” and then “overclocking.” It’s super frustrating.
I’ve noticed that some metronome apps in the App Store have similar issues, but there’s one called “Professional Metronome” that’s rock solid with no such problems. What kind of magic are they using? Any experts out there who can help? Thanks in advance!
P.S. I’ve already enabled background audio permissions.
The professional metronome that has no issues: https://link.zhihu.com/?target=https%3A//apps.apple.com/cn/app/pro-metronome-%25E4%25B8%2593%25E4%25B8%259A%25E8%258A%2582%25E6%258B%258D%25E5%2599%25A8/id477960671
Bug Report: ScreenCaptureKit System Audio Capture Crashes with EXC_BAD_ACCESS
Summary
When using ScreenCaptureKit to capture system audio for extended periods, the application crashes with EXC_BAD_ACCESS in Swift's error handling runtime. The crash occurs in swift_getErrorValue when trying to process an error from the SCStream delegate method didStopWithError. This appears to be a framework-level issue in ScreenCaptureKit or its underlying ReplayKit implementation.
Environment
macOS Sonoma 14.6.1
Swift 5.8
ScreenCaptureKit framework
Detailed Description
Our application captures system audio using ScreenCaptureKit's audio capture capabilities. After successfully capturing for several minutes (typically after 3-4 segments of 60-second recordings), the application crashes with an EXC_BAD_ACCESS error. The crash happens when the Swift runtime attempts to process an error in the SCStreamDelegate.stream(_:didStopWithError:) method.
The crash consistently occurs in swift_getErrorValue when attempting to access the class of what appears to be a null object. This suggests that the error being passed from the system framework to our delegate method is malformed or contains invalid memory.
Steps to Reproduce
Create an SCStream with audio capture enabled
Add audio output to the stream
Start capture and write audio data to disk
Allow the capture to run for several minutes (3-5 minutes typically triggers the issue)
The app will crash with EXC_BAD_ACCESS in swift_getErrorValue
Code Sample
func stream(_ stream: SCStream, didStopWithError error: Error) {
print("Stream stopped with error: \(error)") // Crash occurs before this line executes
}
func stream(_ stream: SCStream, didOutputSampleBuffer sampleBuffer: CMSampleBuffer, of type: SCStreamOutputType) {
guard type == .audio, sampleBuffer.isValid else { return }
// Process audio data...
}
Expected Behavior
The error should be properly propagated to the delegate method, allowing for graceful error handling and recovery.
Actual Behavior
The application crashes with EXC_BAD_ACCESS when the Swift runtime attempts to process the error in swift_getErrorValue.
Crash Log Details
Thread #35, queue = 'com.apple.NSXPCConnection.m-user.com.apple.replayd', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
frame #0: 0x0000000194c3088c libswiftCore.dylib`swift::_swift_getClass(void const*) + 8
frame #1: 0x0000000194c30104 libswiftCore.dylib`swift_getErrorValue + 40
frame #2: 0x00000001057fba30 shadow`NewScreenCaptureService.stream(stream=0x0000600002de6700, error=Swift.Error @ 0x000000016b7b5e30) at NEW+ScreenCaptureService.swift:365:15
frame #3: 0x00000001057fc050 shadow`@objc NewScreenCaptureService.stream(_:didStopWithError:) at <compiler-generated>:0
frame #4: 0x0000000219ec5ca0 ScreenCaptureKit`-[SCStreamManager stream:didStopWithError:] + 456
frame #5: 0x00000001ca68a5cc ReplayKit`-[RPScreenRecorder stream:didStopWithError:] + 84
frame #6: 0x00000001ca696ff8 ReplayKit`-[RPDaemonProxy stream:didStopWithError:] + 224
Printing description of stream._streamQueue:
error: ObjectiveC.id:4294967281:18: note: 'id' has been explicitly marked unavailable here
public typealias id = AnyObject
^
error: /var/folders/v4/3xg1hmp93gjd8_xlzmryf_wm0000gn/T/expr23-dfa421..cpp:1:65: 'id' is unavailable in Swift: 'id' is not available in Swift; use 'Any'
Swift._DebuggerSupport.stringForPrintObject(Swift.UnsafePointer<id>(bitPattern: 0x104ae08c0)!.pointee)
^~
ObjectiveC.id:2:18: note: 'id' has been explicitly marked unavailable here
public typealias id = AnyObject
^
warning: /var/folders/v4/3xg1hmp93gjd8_xlzmryf_wm0000gn/T/expr23-dfa421..cpp:5:7: initialization of variable '$__lldb_error_result' was never used; consider replacing with assignment to '_' or removing it
var $__lldb_error_result = __lldb_tmp_error
~~~~^~~~~~~~~~~~~~~~~~~~
_
Before the crash, we observed this error message in the console:
[ERROR] *****SCStream*****RemoteAudioQueueOperationHandlerWithError:1015 Error received from the remote queue -16665
Additional Context
The issue occurs consistently after approximately 3-4 successful audio segment recordings of 60 seconds each
Commenting out custom segment rotation logic does not prevent the crash
The crash involves XPC communication with Apple's ReplayKit daemon
The error appears to be corrupted or malformed when crossing the XPC boundary
Workarounds Attempted
Added proper thread safety for all published properties using DispatchQueue.main.async
Implemented more robust error handling in the delegate methods
None of these approaches prevented the crash since it occurs at the Swift runtime level before our code executes.
Impact
This issue prevents reliable long-duration audio capture using ScreenCaptureKit.
This bug significantly limits the usefulness of ScreenCaptureKit for any application requiring continuous system audio capture for more than a few minutes.
Perhaps this issue might be related to a macOS bug where the system dialog indicates that the screen is being shared, even though nothing is actually being shared. Moreover, when attempting to stop sharing, nothing happens.
The documentation for the Apple Music API indicates that the genreNames field for a given artist (see https://developer.apple.com/documentation/applemusicapi/artists/attributes-data.dictionary) is an array of strings. However, it only appears as though you return ONE SINGLE GENRE per Artist, regardless of how many genres might be attached to that artist's albums.
Am I missing something? Is there an artist where multiple genres may be returned, or is this a bug in the documentation?
Hello,
I have an existing AUv3 instrument plugin. In the plug in, users can access files (audio files, song projects) via a UIDocumentPickerViewController
In Logic Pro, (and some other hosts, but not all), the document picker is unable to receive touches, while a keyboard case is attached to the iPad.
Removing the case (this is an Apple brand iPad case) allows the interactions to resume and allows me to pick files in the usual way.
One of my users reports this non-responsive behavior occurs even after disconnecting their keyboard.
I have fiddled with entitlements all day, and have determined that is not the issue, since the keyboard disconnection appears to fix it every time for me.
Here is my, very boilerplate, presentation code :
guard let type = UTType("com.my.type") else {
return
}
let fileBrowser = UIDocumentPickerViewController(forOpeningContentTypes: [type])
fileBrowser.overrideUserInterfaceStyle = .dark
fileBrowser.delegate = self
fileBrowser.directoryURL = myFileFolderURL()
self.present(fileBrowser, animated: true) {
AVCaptureVideoDataOutput.preparesCellularRadioForNetworkConnection requires com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning. But I cannot acquire its entitlement. I can't find its entitlement on 'Certificates, Identifiers & Profiles'. Any solutions?
Provisioning profile "iOS Team Provisioning Profile: ......" doesn't include the com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning entitlement.
We are having issues with ScreenCaptureKit. Our use case is the following:
We have multiple applications that each starts a stream capture, using ScreenCaptureKit. It works fine when just one application is streaming, but when starting multiple streams continuesly, all streams stops or crashes, without ScreenCaptureKit reporting an error back.
Restarting replayd for the user will allow us to start streaming again, if the streaming applications are restartet too.
We have build a small test program that we have tested on different Macs, running different versions of macOS, with identical results. The test program just calls the 'getShareableContentExcludingDesktopWindows' function multiple times, since this was the simplest way to show the problem.
Our test setup is the following:
Mac Mini M2 macOS 13.6
MacBook Pro M3 macOS 14.4
MacBook Pro M3 macOS 15.1
Code main.m
#import <Foundation/Foundation.h>
#import <ScreenCaptureKit/ScreenCaptureKit.h>
@interface Runner : NSObject
@property(atomic, assign) BOOL keepRunning;
@property(atomic, retain) SCShareableContent* availableWindows;
-(void) updateAvailableWindows;
-(void) notif:(NSNotification*) aNotif;
@end
int main(int argc, const char * argv[]) {
@autoreleasepool {
NSRunLoop* loo = [NSRunLoop mainRunLoop];
Runner* r = [[Runner alloc] init];
[r updateAvailableWindows];
while (r.keepRunning)
[loo runUntilDate:[NSDate distantFuture]];
NSLog(@"Program exit");
}
return 0;
}
@implementation Runner
-(instancetype) init
{
self = [super init];
if(self){
_keepRunning = YES;
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notif:) name:@"windowWasNotFound" object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notif:) name:@"windowWasFound" object:nil];
}
return self;
}
-(void) updateAvailableWindows
{
@autoreleasepool {
NSLog(@"begin");
[SCShareableContent getShareableContentExcludingDesktopWindows:NO onScreenWindowsOnly:YES completionHandler:^(SCShareableContent* content, NSError* error){
NSLog(@"running");
if(!error){
self.availableWindows = content;
for (__unused SCWindow* aWin in self.availableWindows.windows) {
[NSThread sleepForTimeInterval:0.01];
}
[[NSNotificationCenter defaultCenter] postNotificationName:@"windowWasFound" object:self.availableWindows];
}
else{
[[NSNotificationCenter defaultCenter] postNotificationName:@"windowWasNotFound" object:nil];
}
}];
}
}
-(void) notif:(NSNotification*) aNotif
{
if(aNotif.object)
[self performSelectorOnMainThread:@selector(updateAvailableWindows) withObject:nil waitUntilDone:NO];
else{
NSLog(@"Not Found");
self.keepRunning = NO;
}
}
@end
How to replicate:
Compile and run the program from multiple terminal windows (terminal must be granted screen recording permission) and notice that the output stops, when the replayd stops responding (our assumption). Restarting the application does nothing, before the replayd also is restarted.
Running th application in Xcode gives the following error:
[ERROR] -[RPDaemonProxy fetchShareableContentWithOption:windowID:currentProcess:withCompletionHandler:]_block_invoke:902 error: 4097
This error is not something we have been able to detect in our applications - and since the only workaround is restarting replayd and the applications, catching the error would help us.
Add RPSystemBroadcastPickerView to the app,
After clicking, no method of SampleHandler is triggered
Hi guys,
Can I use CMIO to achieve the following feature on macOS when a USB device (Camera/Mic/Speaker) is connected:
When a third-party video conferencing app is not in a meeting, ensure the app defaults to using the USB device (Camera/Mic/Speaker).
When a third-party conferencing app is in a meeting, ensure the app automatically switches to the USB device (Camera/Mic/Speaker).
In SwiftUI there is a built-in component for displaying album artworks called Artwork but there is no equivalent for UIKit.
My current approach is to use the .url() method to read image's URL and download the image or read it from the disk but the performance is much worse than it was previously with MPMediaItem's artworkImage method.
let artworkQueue = DispatchQueue(
label: "MusicKit-ArtworkQueue",
qos: .default,
attributes: .concurrent
)
let artworkSemaphore = DispatchSemaphore(value: 5)
extension Song {
func artworkImage(for size: CGSize, completion: @escaping (UIImage?) -> Void) {
artworkQueue.async {
artworkSemaphore.wait()
defer {
artworkSemaphore.signal()
}
let imageURL = artwork?.url(
width: Int(size.width),
height: Int(size.height)
)
// I hate doing this as it might very well break in the future
guard let imageURL, imageURL.scheme == "musicKit"
else {
return completion(nil)
}
guard let imageData = try? Data(contentsOf: imageURL),
let image = UIImage(data: imageData) else {
return completion(nil)
}
completion(image)
}
}
}
I really dislike this approach because it feels hacky but somewhat works. You might ask what's the semaphore for? Well, without it I could notice that MusicKit was choking and after reading too many artworks at once.
Can someone from Apple please provide us with an example on how to use MusicKit with UIKit properly?
Ideally (IMO) we would have a method defined on Song and other MusicKit structures that returns the image for us, just like MPMediaItem had the .artwork() method. It would make our lives so much easier.
Hi everyone,
I'm developing a visionOS app for Apple Vision Pro, and I've encountered an issue related to window resizing at runtime when using AVPlayer to play a live HLS stream.
✅ What I'm Trying to Do
Play a live HLS stream (from Wowza) inside my app using AVPlayer.
Support resizing the immersive window using Vision Pro’s built-in runtime scaling gesture.
Stream works fine at default window size when the app launches.
❌ Problem
If I resize the app’s window at runtime (using the Vision Pro pinch-drag gesture), then try to start the stream, it does not play.
Instead, it just shows the "Loading live stream..." state and never proceeds to playback.
This issue only occurs after resizing the window — if I don’t resize, the stream works perfectly every time.
🧪 What I’ve Tried
Verified the HLS URL — it’s working and plays fine in Safari and in the app before resizing.
Set .automaticallyWaitsToMinimizeStalling = false on AVPlayer.
Observed that .status on AVPlayerItem never reaches .readyToPlay after resizing.
Tried to force window size back using UIWindowScene.requestGeometryUpdate(...), but behavior persists.
I’ve never had a problem with any update before but as soon as I updated to 18.3 update my camera decided to start blurring when it’s in 1x & 2x, I use my camera daily for work and this is unacceptable. I’m wondering if anyone else is having this issue, it’s really frustrating..
I often find when doing basic actions in MusicKit it is incredibly slow compared to Apple's Music App. I've tried different versions, devices, networks, Apple's sample code, it all throughout the last several years, and it is all the same. Does anyone else have this issue?