I am using MusicKit ApplicationMusicPlayer to play music in my app. Everything works fine as long as I'm not playing large playlists that contain hundreds of songs. When I to play collection of songs that is larger than around 300 I'm always getting the error message saying:
"Prepare to play failed" UserInfo={NSDebugDescription=Prepare to play failed, NSUnderlyingError=0x121d42dc0 {Error Domain=MPMusicPlayerControllerErrorDomain Code=9 "Remote call timed out" UserInfo={NSDebugDescription=Remote call timed out}}}))
It doesn't matter if songs are downloaded to the device or not.
I am aware that there is another initializer for player's queue that accepts Playlist instances but in my app users can choose to sort playlist tracks in different order than the default and that makes using that initializer not feasible for me.
I tried everything I could think of, I tried to fall back on MPMusicPlayerController and pass array of MPMusicPlayerPlayParameters to it but the result was the same.
typealias QueueEntry = ApplicationMusicPlayer.Queue.Entry
let player = ApplicationMusicPlayer.shared
let entries: [QueueEntry] = tracks
.compactMap {
guard let song = $0 as? Song else { return nil }
return QueueEntry(song)
}
Task(priority: .high) { [player] in
do {
player.queue = .init(entries, startingAt: nil)
try await player.play() // prepareToPlay failed
} catch {
print(error)
}
}
Explore the integration of media technologies within your app. Discuss working with audio, video, camera, and other media functionalities.
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I'm building a camera app that does some post processing after the photo has been taken. With 12MP the processing is pretty good, but larger images 24MP is very slow.
I created a very simple example to demonstrate the issue, which is loading an image and the rendering it to data.
let context = CIContext()
let imageUrl = Bundle.main.url(forResource: "12mp", withExtension: "jpg")!
let data = try! Data(contentsOf: imageUrl)
let ciImage = CIImage(data: data)!
let start = CFAbsoluteTimeGetCurrent()
let data = context.jpegRepresentation(of: ciImage, colorSpace: context.workingColorSpace!)
print(data?.count)
print("Resize Completed: " + String(CFAbsoluteTimeGetCurrent() - start))
Running this code on an iPhone 16 Pro with different images produces these benchmarks:
12MP => 0.03s
24MP => 1.22s
48MP => 2.98s
I understand that processing time will increase with resolution but it doesn't seem linear. I have tried setting different CiContext options such as .useSoftwareRenderer: false but it has made no difference.
From profiling the process it looks like the JPEG decoding is the bottle neck. This is for a 48MP Image:
Is there any way this can be improved?
am new to using Swift for a Mac Application. I am trying to control an external UVC-compliant camera focus and other capabilities. However, I'm having trouble with this and don't know where to start. I have downloaded an application from the App Store and it can control the focus and other capabilities.
I've tried IOKit but this seems to be complicated and this does not return any capabilities or control the camera.
I also tried AVfoundation and was able to open the camera, but using the following code did not work for me. as a device.isFocusPointOfInterestSupported returns false and without checking the app crashes.
@IBAction func focusChanged(_ sender: NSSlider) {
do {
guard let device = videoDevice else { return }
try device.lockForConfiguration()
// Check if focus mode and point of interest are supported
if device.isFocusModeSupported(.locked) {
device.focusMode = .locked
}
if device.isFocusPointOfInterestSupported {
// Map the slider value (0.0 to 1.0) to the focus point's X coordinate
let focusX = CGFloat(sender.doubleValue)
let focusPoint = CGPoint(x: focusX, y: 0.5) // Y coordinate is typically 0.5 (centered vertically)
device.focusPointOfInterest = focusPoint
} else {
print("Focus point of interest is not supported on this device.")
}
device.unlockForConfiguration()
// Log focus settings
print("Focus point: \(device.focusPointOfInterest)")
print("Focus mode: \(device.focusMode.rawValue)")
} catch {
print("Error adjusting focus: \(error)")
}
Any help or advice is much appreciated.
I’m spot-checking some of the data I’m extracting from the Apple Music Feed parquet files and finding numerous issues of invalid album IDs.
For example, just looking at any album with a primary artist id of 163043, I see a few albums that are not available at music.apple.com/us/album/NNN. These include:
981094158 - Time and the River
1803443737 - Celebration (Live New York ’80)
1525426873 - Anything You Want: The Warner-Reprise-Elektra Years
I notice that neither of these album ids are returned using the general Music API, so I’m a bit confused why they would exist in the parquet files at all.
Thanks.
Topic:
Media Technologies
SubTopic:
General
Dear Apple Developer Forum,
I have a question regarding the AVCaptureDevice on iOS. We're trying to capture photos in the best quality possible along with depth data with the highest accuracy possible. We were delighted when we saw AVCaptureDevice could be initialized with the AVMediaType=.depthData which works as expected (depthData is a part of the AVCapturePhoto). When setting to AVMediaType=.video, we still receive depth data (of same quality according to our own internal tests). That confused us.
Mind you, we set the device format and depth format as well:
private func getDeviceFormat() throws -> AVCaptureDevice.Format {
// Ensures high video format and an appropriate color profile.
let format = camera?.formats.first(where: {
$0.isHighPhotoQualitySupported &&
$0.supportedDepthDataFormats.count > 0 &&
$0.formatDescription.mediaSubType.rawValue == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange
})
// Check and see if it's available.
guard format != nil else {
throw CaptureDeviceError.necessaryFormatNotAvailable
}
return format!
}
private func getDepthDataFormat(for format: AVCaptureDevice.Format) throws -> AVCaptureDevice.Format {
// Access the depth format.
let depthDataFormat = format.supportedDepthDataFormats.first(where: {
$0.formatDescription.mediaSubType.rawValue == kCVPixelFormatType_DepthFloat32
})
// Check if it exists
guard depthDataFormat != nil else {
throw CaptureDeviceError.necessaryFormatNotAvailable
}
// Returns it.
return depthDataFormat!
}
We're wondering, what steps we can take to ensure the best quality photo, along with the most accurate depth data? What properties are the most important, which have an effect, which don't? Are there any ways we can optimize our current configuration? We find it difficult as there's very limited guides and explanations on the media subtypes, for example kCVPixelFormatType_420YpCbCr8BiPlanarFullRange. Is it the best? Is it the best for our use case of high quality photo + most accurate depth data?
Important comment: Our App only runs on iPhone 14 Pro, iPhone 15 Pro, iPhone 16 Pro on the latest iOS versions.
We hope someone with greater knowledge at Apple can help us and guide us on how we can have the photos of best quality and depth data with most accuracy.
Thank you very much!
Kind regards.
I want to create a Live Photo. The project includes a .jpg image and a .mov video (2 seconds).
Two permissions in xcode have been added:
Privacy - Photo Library Usage Description
Privacy - Photo Library Additions Usage Description
Simulate: iphone 16, ios 18.3
The codes in ContentView.swift :
private func saveLivePhoto(imageURL: URL, videoURL: URL, completion: @escaping (Bool, Error?) -> Void) {
PHPhotoLibrary.shared().performChanges {
let creationRequest = PHAssetCreationRequest.forAsset()
let options = PHAssetResourceCreationOptions()
options.shouldMoveFile = false
creationRequest.addResource(with: .photo, fileURL: imageURL, options: options)
creationRequest.addResource(with: .pairedVideo, fileURL: videoURL, options: options)
} completionHandler: { success, error in
DispatchQueue.main.async {
print(error)
completion(success, error)
}
}
}
guard let imageURL = Bundle.main.url(forResource: "livephoto", withExtension: "jpeg"),
let videoURL = Bundle.main.url(forResource: "livephoto", withExtension: "mov") else {
showAlertMessage(title: "error", message: "cant find Live Photo ")
return
}
print("imageURL: \(imageURL)")
print("videoURL: \(videoURL)")
saveLivePhoto(imageURL: imageURL, videoURL: videoURL) { success, error in
if success {
xxxxx
} else {
xxxxx
}
}
Really need help, thanks
Hi, I have a problem when I want to attach my grayscale depth map image into the real image. The produced depth map doesn't have the cameraCalibration value which should responsible to align the depth data to the image. How do I align the depth map? I saw an article about it but it is not really detailed so I might be missing some process.
I tried to:
convert my depth map into pixel buffer
create image destination ref and add the image there.
add the auxData (depth map dict)
This is the output:
There is some black space there and my RGB image colour changes
We are currently working on a CarPlay navigation app and so far everything is working well except for speaking turn notifications.
Our TTS implementation works fine on the phone and works fine on CarPlay if the voice is spoken over the speaker in the car. If users connect a BT headset to the car and listen through that headset, then the voice commands are chopped up / stutter.
Why would users use BT headset? Well, we are working on a motorcycle app, and there are no speakers usually on a motorcycle.
It sounds like the BT channel is opened and closed repeatedly for every character / word spoken. This happens on different CarPlay devices and different Bluetooth headsets, we have reports from multiple users that they find this behavior annoying and that other apps work fine.
Is this a known issue? Are there possible workaround?
I set the device format and colorspace to Apple Log and turn off the HDR, why the movie output is still in HDR format rather than ProRes Log?
Full runnable demo here:
https://github.com/SpaceGrey/ColorSpaceDemo
session.sessionPreset = .inputPriority
// get the back camera
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: .video, position: .back)
backCamera = deviceDiscoverySession.devices.first!
try! backCamera.lockForConfiguration()
backCamera.automaticallyAdjustsVideoHDREnabled = false
backCamera.isVideoHDREnabled = false
let formats = backCamera.formats
let appleLogFormat = formats.first { format in
format.supportedColorSpaces.contains(.appleLog)
}
print(appleLogFormat!.supportedColorSpaces.contains(.appleLog))
backCamera.activeFormat = appleLogFormat!
backCamera.activeColorSpace = .appleLog
print("colorspace is Apple Log \(backCamera.activeColorSpace == .appleLog)")
backCamera.unlockForConfiguration()
do {
let input = try AVCaptureDeviceInput(device: backCamera)
session.addInput(input)
} catch {
print(error.localizedDescription)
}
// add output
output = AVCaptureMovieFileOutput()
session.addOutput(output)
let connection = output.connection(with: .video)!
print(
output.outputSettings(for: connection)
)
/*
["AVVideoWidthKey": 1920, "AVVideoHeightKey": 1080, "AVVideoCodecKey": apch,<----- prores has enabled.
"AVVideoCompressionPropertiesKey": {
AverageBitRate = 220029696;
ExpectedFrameRate = 30;
PrepareEncodedSampleBuffersForPaddedWrites = 1;
PrioritizeEncodingSpeedOverQuality = 0;
RealTime = 1;
}]
*/
previewSource = DefaultPreviewSource(session: session)
queue.async {
self.session.startRunning()
}
}
Hi I'm working on a project that require video frame PTS to be consistent between original video and a transcoded one. It's working fairly well on regular mp4, however if I set preferredOutputSegmentInterval to have generate a fMP4 output, even I specified the initialSegmentStartTime as 0, it always add one frame pts offset to all frames.
For example: if I use the code sample provided by Apple: https://developer.apple.com/videos/play/wwdc2020/10011/?time=406, useffprobe -select_streams v:0 -show_entries packet=pts_time -of csv ~/Downloads/fmp4/prog_index.m3u8 to display the pts of the output, it doesn't start from 0, but has some one frame pts offset. I also tried open with MP4Box, it also shows the first frames dts and cts are not start from 0.
However, if I use AVAssetReader to read the same output video, and get the PTS from 1st frame, it's returning 0. So I can't use it to calculate the pts difference between 2 videos neither.
Can I get some help to understand why there is difference between AVAssetWriter/Reader fMP4's pts and others like ffprobe?
I am following the Apple sample code and trying to add a manual focus lens position slider:
@available(iOS 18.0, *)
private func addCameraControls() {
if !self.session.controls.isEmpty {
for control in self.session.controls {
self.session.removeControl(control)
}
}
self.cameraControlFocusSlider = nil
//Focus Slider
if self.videoDevice!.isLockingFocusWithCustomLensPositionSupported {
self.cameraControlFocusSlider = AVCaptureSlider("Focus", symbolName: "dot.square", in: 0.0...1.0)
self.cameraControlFocusSlider!.setActionQueue(self.sessionQueue) { focusValue in
//Do manual focus
}
if self.session.canAddControl(self.cameraControlFocusSlider!) {
self.session.addControl(self.cameraControlFocusSlider!)
}
}
}
So there are these AVCaptureSessionControlsDelegate methods:
final func sessionControlsDidBecomeActive(_ session: AVCaptureSession) {
print ("sessionControlsDidBecomeActive")
}
final func sessionControlsWillEnterFullscreenAppearance(_ session: AVCaptureSession) {
print ("sessionControlsWillEnterFullscreenAppearance")
}
final func sessionControlsWillExitFullscreenAppearance(_ session: AVCaptureSession) {
print ("sessionControlsWillExitFullscreenAppearance")
}
final func sessionControlsDidBecomeInactive(_ session: AVCaptureSession) {
print ("sessionControlsDidBecomeInactive")
}
So when self.cameraControlFocusSlider is presented, I have to show the current value of the lense position. Lens position can change from auto focus and also from manual focus by the user using the app UI. Is there a way to see if self.cameraControlFocusSlider is active or being used?
Please note that I will have more than one AVCaptureSlider in the final code.
We are encountering an issue where AVPlayer throws the error:
Error Domain=AVFoundationErrorDomain Code=-11819 "Cannot Complete Action" > Underlying Error Domain[(null)]:Code[0]:Desc[(null)]
This error seems to occur intermittently during video playback, especially after extended usage or when switching between different streams. We observe Error 11819 (AVFoundationErrorDomain) in Conviva platform that some of our users experience it but we couldn't reproduce it so far and we’re need support to determine the root cause and/or best practices to prevent it.
Some questions we have:
What typically triggers this error?
Could it be related to memory/resource constraints, network instability, or backgrounding?
Are there any recommended ways to handle or recover from this error gracefully?
Any insights or guidance would be greatly appreciated. Thanks!
Topic:
Media Technologies
SubTopic:
Streaming
I have an app that records a health provider’s conversation with a patient. I am using Audio Queue Services for this. If a phone call comes in while recording, the doctor wants to be able to ignore the call and continue the conversation without touching the phone. If the doctor answers the call, that’s fine – I will stop the recording. I can detect when the call comes in and ends using CXCallObserver and AVAudioSession.interruptionNotification. Unfortunately, when a call comes in and before it is answered or dismissed, the audio is suppressed. After the call is dismissed, the audio continues to be suppressed. How can I continue to get audio from the mic as long as the user does not answer the phone call?
Topic:
Media Technologies
SubTopic:
Audio
My app is a camera app that supports Picture-in-Picture (PiP) mode.
Normally, when the device rotates, I get the device orientation from iOS and use it to rotate the camera feed so that the preview stays correctly aligned.
However, when the app enters PiP mode, it is considered to be in the background, and I can no longer receive orientation updates from the system.
As a result, I can’t apply rotation corrections to the camera video in PiP mode.
Is there any way to retrieve device orientation while the app is in the background (specifically during PiP mode)?
Any guidance would be greatly appreciated.
Thank you!
When I play an m3u8 video using AVPlayer, it can play smoothly at 2x speed. However, when I set it to 3x speed, the playback is not smooth and there is no sound.
Topic:
Media Technologies
SubTopic:
Video
Hi all,
i can successfully match music using shazamkit on Apple using SwiftUI, a simple app that let user to load an audio file and exctracts the relative match, while i am unable to match music using shamzamkit on Android. I am trying to make the same simple app but i cannot match music as i get MATCH_ATTEMPT_FAILED every time i try to. I don't know what i am doing wrong but the shazam part in the kotlin Android code is in this method :
suspend fun processAudioFileInBackground(
filePath: String,
developerTokenProvider: DeveloperTokenProvider
) = withContext(Dispatchers.IO) {
val bufferSize = 1024 * 1024
val audioFile = FileInputStream(filePath)
val byteBuffer = ByteBuffer.allocate(bufferSize)
byteBuffer.order(ByteOrder.LITTLE_ENDIAN)
var bytesRead: Int
while (audioFile.read(byteBuffer.array()).also { bytesRead = it } != -1) {
val signatureGenerator = (ShazamKit.createSignatureGenerator(AudioSampleRateInHz.SAMPLE_RATE_44100) as ShazamKitResult.Success).data
signatureGenerator.append(byteBuffer.array(), bytesRead, System.currentTimeMillis())
val signature = signatureGenerator.generateSignature()
println("Signature: ${signature.durationInMs}")
val catalog = ShazamKit.createShazamCatalog(developerTokenProvider, Locale.ENGLISH)
val session = (ShazamKit.createSession(catalog) as ShazamKitResult.Success).data
val matchResult = session.match(signature)
println("MatchResult : $matchResult")
setMatchResult(matchResult)
byteBuffer.clear()
}
audioFile.close()
}
I noticed that changing Locale in catalog creation results in different result as i get NoMatch without exception. Can you please help me with this?
Topic:
Media Technologies
SubTopic:
Audio
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
Hello Apple Developers,
I’m reaching out to the community with a concept that I truly believe could be a natural fit for the Apple ecosystem:
A privacy-focused, iOS-exclusive dating app designed to enhance connections between Apple users while staying true to Apple’s commitment to security and user privacy.
The idea is to create an iOS-only dating platform that fosters relationships between users who are part of the Apple ecosystem. The app would integrate seamlessly with Apple’s services (iMessage, FaceTime, Siri, etc.) and provide a premium user experience, where privacy is a priority.
Apple users already prefer to communicate using Apple services (iMessage, FaceTime). A dating app designed specifically for iOS users would deepen this ecosystem lock-in, making it easier for Apple customers to connect within a trusted space.
Apple is already known for its privacy focus, and an iOS-exclusive dating app would build upon that reputation. It would ensure secure, private interactions, minimizing the risks associated with data sharing in most dating apps today.
The app could integrate directly with features like iCloud, Apple Pay (for date-night bookings), and Siri (for matchmaking suggestions), offering users a truly native iOS experience.
While the app would remain free to use, here are a few potential monetization methods:
Bundling with Apple One/iCloud+ for premium matchmaking features.
Apple Pay-based date-night deals with local partners.
I’d love to hear your thoughts on whether Apple might be open to this idea. Would there be any challenges from a technical or business perspective in creating a dating app exclusively for iOS users?
I’m looking forward to hearing from you all, and thank you for your time and insights.
Yours Truly,
CapNKirk
P.S. This is an idea. But I do not care who uses, implements, or executes this idea. I just want to see Apple take advantage of it.
I've got a web app built with MusicKit that displays a list of songs.
I have player controls for play, pause, skip next, skip, previous, toggle shuffle and set repeat mode.
All of these work by using music.
The play button, when nothing is playing and nothing is in the queue, will enqueue all the tracks and start playing with the below, for example:
await music.setQueue({ songs, startPlaying: true });
I've implemented a progress slider based on feedback from the "playbackProgressDidChange" listener.
Now, how in the world can I set the volume? This seems like it should be simple, but I am at a complete loss here.
The docs say:
"The volume of audio playback, which is set directly on the HTMLMediaElement as the HTMLMediaElement.volume property. This value ranges between 0, which would be muting the audio, and 1, which would be the loudest possible."
Given that all my controls work off the music instance, I don't understand how I can do that.
In this video from WWDC 2022, music web components are touched on briefly. These are also documented very sparsely. The volume docs are here.
For the life of me, I can't even get the volume web component to display in the UI.
It appears that MusicKit Web is hobbled compared to the native implementation, but surely adjusting volume shouldn't be that hard right?
I'd appreciate any insight on how to do this, including how to get web components to work (in a Next JS app).
Thanks.
For some users in production, there's a high probability that after launching the App, using AVPlayer to play any local audio resources results in the following error. Restarting the App doesn't help.
issue:
[error: Error Domain=AVFoundationErrorDomain Code=-11800 "这项操作无法完成" UserInfo={NSLocalizedFailureReason=发生未知错误(24), NSLocalizedDescription=这项操作无法完成, NSUnderlyingError=0x30311f270 {Error Domain=NSPOSIXErrorDomain Code=24 "Too many open files"}}
I've checked the code, and there aren't actually multiple AVPlayers playing simultaneously. What could be causing this?