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​​Can VideoToolbox properly decode HEVC bitstreams when a single frame is split into multiple slice NALUs?​
I am currently developing an HEVC player using VideoToolbox on an iOS device. I have successfully created an HEVC decoder that receives HEVC streams from our custom image capture and encoding device, and it can decode and display images properly. However, when my image capture and encoding device configures the encoder to output HEVC streams with ​​fragmented NALUs​​ (i.e., an I-frame or P-frame is split and stored across multiple slice NALUs), the iOS decoder can be initialized successfully but fails to decode and output images. ​​Can VideoToolbox properly decode HEVC bitstreams when a single frame is split into multiple slice NALUs?​​ Key Observations: ​​1. Single-NALU frames​​ work fine. ​​2. Multi-NALU frames​​ (sliced I/P-frames) cause decoding failure. 3. The decoder session is created successfully (VTDecompressionSessionCreate returns no error).
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197
May ’25
Indicate Packet Loss With AVAudioConverter for OPUS Decoding
I'm using an AVAudioConverter object to decode an OPUS stream for VoIP. The decoding itself works well, however, whenever the stream stalls (no more audio packet is available to decode because of network instability) this can be heard in crackling / abrupt stop in decoded audio. OPUS can mitigate this by indicating packet loss by passing a null pointer in the C-library to int opus_decode_float (OpusDecoder * st, const unsigned char * data, opus_int32 len, float * pcm, int frame_size, int decode_fec), see https://opus-codec.org/docs/opus_api-1.2/group__opus__decoder.html#ga9c554b8c0214e24733a299fe53bb3bd2. However, with AVAudioConverter using Swift I'm constructing an AVAudioCompressedBuffer like so:         let compressedBuffer = AVAudioCompressedBuffer(             format: VoiceEncoder.Constants.networkFormat,             packetCapacity: 1,             maximumPacketSize: data.count         )         compressedBuffer.byteLength = UInt32(data.count)         compressedBuffer.packetCount = 1   compressedBuffer.packetDescriptions! .pointee.mDataByteSize = UInt32(data.count)         data.copyBytes(             to: compressedBuffer.data .assumingMemoryBound(to: UInt8.self),             count: data.count         ) where data: Data contains the raw OPUS frame to be decoded. How can I specify data loss in this context and cause the AVAudioConverter to output PCM data whenever no more input data is available? More context: I'm specifying the audio format like this:         static let frameSize: UInt32 = 960         static let sampleRate: Float64 = 48000.0         static var networkFormatStreamDescription = AudioStreamBasicDescription(             mSampleRate: sampleRate,             mFormatID: kAudioFormatOpus,             mFormatFlags: 0,             mBytesPerPacket: 0,             mFramesPerPacket: frameSize,             mBytesPerFrame: 0,             mChannelsPerFrame: 1,             mBitsPerChannel: 0,             mReserved: 0         )         static let networkFormat = AVAudioFormat( streamDescription: &networkFormatStreamDescription )! I've tried 1) setting byteLength and packetCount to zero and 2) returning nil but setting .haveData in the AVAudioConverterInputBlock I'm using with no success.
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926
May ’25
401 Authorization error for Music Feed API
I've established proper authorization for general music api calls, but when I use that same authorization to retrieve metadata for the latest music feeds (see https://developer.apple.com/documentation/applemusicfeed/requesting-a-feed-export), I get a 401 Unauthorized error. As per the documentation, I'm simply issuing a GET against https://api.media.apple.com/v1/feed/album/latest. Are there different entitlements needed for the Music Feed API?
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109
May ’25
MusicKit playbackTime Accuracy
Hello, Has anyone else experienced variations in the accuracy of the playbackTime value? After a few seconds of playback, the reported time adjusts by a fraction of a second, making it difficult to calculate the actual playbackTime of the audio. This can be recreated by playing a song in MusicKit, recording the start time of the audio, playing for at least 10-20 seconds, and then comparing the playbackTime value to one calculated using the start time of the audio. In my experience this jump occurs after about 10 seconds of playback. Any help would be appreciated. Thanks!
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131
May ’25
H.265 Decoding with VideoToolBox
I am creating an app that decodes H.265 elementary streams on iOS. I use VideoToolBox to decode from H.265 to NV12. The decoded data is enqueued in the CMSampleBufferDisplayLayer as a CMSampleBuffer. However, nothing is displayed in the VideoPlayerView. It remains black. The decoding in VideoToolBox is successful. I confirmed this by saving the NV12 data in the CMSampleBuffer to a file and displaying it using a tool. Why is nothing displayed in the VideoPlayerView? I can provide other source code as well. // // ContentView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI struct ContentView: View { var body: some View { VStack { Text("H.265 Player (temp.h265)") .font(.headline) VideoPlayerView() .frame(width: 360, height: 640) // Adjust or make it responsive for iOS } .padding() } } #Preview { ContentView() } // // VideoPlayerView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI import AVFoundation struct VideoPlayerView: UIViewRepresentable { // Return an H265Player as the coordinator, and start playback there. func makeCoordinator() -> H265Player { H265Player() } func makeUIView(context: Context) -> UIView { let uiView = UIView(frame: .zero) // Base layer for attaching sublayers uiView.backgroundColor = .black // Screen background color (for iOS) // Create the display layer and add it to uiView.layer let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.bounds displayLayer.backgroundColor = UIColor.clear.cgColor uiView.layer.addSublayer(displayLayer) // Start playback context.coordinator.startPlayback() return uiView } func updateUIView(_ uiView: UIView, context: Context) { // Reset the frame of the AVSampleBufferDisplayLayer when the view's size changes. let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.layer.bounds // Optionally update the layer's background color, etc. uiView.backgroundColor = .black displayLayer.backgroundColor = UIColor.clear.cgColor // Flush transactions if necessary CATransaction.flush() } } // // H265Player.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import Foundation import AVFoundation import CoreMedia class H265Player: NSObject, VideoDecoderDelegate { let displayLayer = AVSampleBufferDisplayLayer() private var decoder: H265Decoder? override init() { super.init() // Initial configuration for the display layer displayLayer.videoGravity = .resizeAspect // Initialize the decoder (delegate = self) decoder = H265Decoder(delegate: self) // For simple playback, set isBaseline to true decoder?.isBaseline = true } func startPlayback() { // Load the file "cars_320x240.h265" guard let url = Bundle.main.url(forResource: "temp2", withExtension: "h265") else { print("File not found") return } do { let data = try Data(contentsOf: url) // Set FPS and video size as needed let packet = VideoPacket(data: data, type: .h265, fps: 30, videoSize: CGSize(width: 1080, height: 1920)) // Decode as a single packet decoder?.decodeOnePacket(packet) } catch { print("Failed to load file: \(error)") } } // MARK: - VideoDecoderDelegate func decodeOutput(video: CMSampleBuffer) { // When decoding is complete, send the output to AVSampleBufferDisplayLayer displayLayer.enqueue(video) } func decodeOutput(error: DecodeError) { print("Decoding error: \(error)") } }
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728
May ’25
iOS AUv3 extension: no Icon shown in host
Hi, I'm working on an AUv3 project. The app itself displays my icon. However the Auv3 extension does not display any icon in any host app (AUM, Drambo, etc.0). I thought that the extension would inherit the host app icon but that it does not appear to be the case. I tried to add the icon as a 1024x1024 file to the extension target and the update my extension plist file withe a CFBundleIconFile key but no luck either. It must surely be really easy. What am I missing? Thanks in advance for your help!
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152
May ’25
how to enumerate build-in media devices?
Hello, I need to enumerate built-in media devices (cameras, microphones, etc.). For this purpose, I am using the CoreAudio and CoreMediaIO frameworks. According to the table 'Daemon-Safe Frameworks' in Apple’s TN2083, CoreAudio is daemon-safe. However, the documentation does not mention CoreMediaIO. Can CoreMediaIO be used in a daemon? If not, are there any documented alternatives to detect built-in cameras in a daemon (e.g., via device classes in IOKit)? Thank you in advance, Pavel
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171
May ’25
SystemAudio Capture API Fails with OSStatus error 1852797029 (kAudioCodecIllegalOperationError)
Issue Description I'm implementing a system audio capture feature using AudioHardwareCreateProcessTap and AudioHardwareCreateAggregateDevice. The app successfully creates the tap and aggregate device, but when starting the IO procedure with AudioDeviceStart, it sometimes fails with OSStatus error 1852797029. (The operation couldn’t be completed. (OSStatus error 1852797029.)) The error occurs inconsistently, which makes it particularly difficult to debug and reproduce. Questions Has anyone encountered this intermittent "nope" error code (0x6e6f7065) when working with system audio capture? Are there specific conditions or system states that might trigger this error sporadically? Are there any known workarounds for handling this intermittent failure case? Any insights or guidance would be greatly appreciated. I'm wondering if anyone else has encountered this specific "nope" error code (0x6e6f7065) when working with system audio capture.
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189
May ’25
Album parquet files don't include song names
The documentation of the Apple Music Feed API states that the Album object would include songs — a list of songs in the album. As per the doc, this would be an array of object Album.RelatedSong, which would include both an id and nameDefault. Unfortunately, the album parquet files only include the song id and not the name of the song itself. Please advise - is the documentation incorrect or are the recently posted parquet files in error?
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88
May ’25
Invalid album IDs in parquet files
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.
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131
May ’25
How to Get Device Orientation in Background (PiP) Mode?
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!
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May ’25
videoCaptureQueue would make the app crashed when I using IOS 18.4.1
Hi All I have some problem when I using the IOS 18.4.1 I have iphone16 pro and ipad Air, both are updated to IOS 18.4.1 I tried to following sample code. However, when I run the app around 30 seconds to 1 minutes, the application would be crashed When I using another Ipad with IOS 17, it would not have the same problem. https://developer.apple.com/documentation/createml/creating-an-action-classifier-model https://developer.apple.com/documentation/createml/detecting_human_actions_in_a_live_video_feed#overview%29,
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May ’25
I’m using ScreenCaptureKit on macOS to grab frames and measure end-to-end latency (capture → my delegate callback). For each CMSampleBuffer I read:
I’m using ScreenCaptureKit on macOS to grab frames and measure end-to-end latency (capture → my delegate callback). For each CMSampleBuffer I read: let pts = CMSampleBufferGetPresentationTimeStamp(sampleBuffer).seconds to get the “capture” timestamp, and I also extract the mach-absolute display time: let attachments = CMSampleBufferGetSampleAttachmentsArray(sampleBuffer, createIfNecessary: false) as? [[SCStreamFrameInfo: Any]] let displayMach = attachments?.first?[.displayTime] as? UInt64 // convert mach ticks to seconds... Then I compare both against the current time: let now = CACurrentMediaTime() let latencyFromPTS = now - pts let latencyFromDisplay = now - displayTimeSeconds But I consistently see negative values for both calculations—i.e. the PTS or displayTime often end up numerically larger than now. This suggests that the “presentation timestamp” and the mach-absolute display time are coming from a different epoch or clock domain than CACurrentMediaTime(). Questions: Which clocks/epochs does ScreenCaptureKit use for PTS and for .displayTime? How can I align these timestamps with CACurrentMediaTime() so that now - pts and now - displayTime reliably yield non-negative real-world latencies? Any pointers on the correct clock conversions or APIs to use would be greatly appreciated.
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May ’25
AVAudioPlayer/SKAudioNode audio no longer plays after interruption
Hi 👋! We have a SpriteKit-based app where we play AVAudio sounds in three different ways: Effects (incl. UI sounds) with AVAudioPlayer. Long looping tracks with AVAudioPlayer. Short animation effects on the timeline of SpriteKit's SKScene files (effectively SKAudioNode nodes). We've found that when you exit the app or otherwise interrupt audio plays, future audio plays often fail. For example, there's a WebKit-based video trailer inside the app, and if you play it, our looping background music track (2.) will stop playing, and won't resume as you close the trailer (return from WebKit). This is probably due to us not manually restarting the track (so may well be easily fixed). Periodically played AVAudioPlayer audio (1.) are not affected. However, the more concerning thing is that the audio tracks on SKScene file timelines (3.) will no longer play. My hypothesis is that AVAudioEngine gets interrupted, and needs to be restarted for those AVAudioNode elements to regain functionality. Thing is, we don't deal with AVAudioEngine at all currently in the app, meaning it is never initiated to begin with. Obviously things return to normal when you remove the app from short-term memory and restart it. However, it seems many of our users aren't doing this, and often report audio failing presumably due to some interruption in the past without the app ever being cleared from memory. Any idea why timeline-run SKAudioNodes would fail like this? Should the app react to app backgrounding/foregrounding regarding audio? Any help would be very much appreciated ✌️!
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204
May ’25
Mic audio before and after a call is answered
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?
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May ’25
MPNowPlayingInfoCenter nowPlayingInfo throttled
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.
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May ’25
Apple Music web player will not work on wkwebview web browser or electron chromium browser.
Hello, I'm trying to create a webbrowser but currently when signed into apple music webplayer I get the following message when I attempt to play on any versions of my webbrowser: Not available on the web You can listen to this in the Apple Music app. Is there a way to setup DRM (assuming this is the issue) with apple to allow my webbrowser to play this content? I believe Apple TV is also affected. Thank you ahead of time.
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May ’25
​​Can VideoToolbox properly decode HEVC bitstreams when a single frame is split into multiple slice NALUs?​
I am currently developing an HEVC player using VideoToolbox on an iOS device. I have successfully created an HEVC decoder that receives HEVC streams from our custom image capture and encoding device, and it can decode and display images properly. However, when my image capture and encoding device configures the encoder to output HEVC streams with ​​fragmented NALUs​​ (i.e., an I-frame or P-frame is split and stored across multiple slice NALUs), the iOS decoder can be initialized successfully but fails to decode and output images. ​​Can VideoToolbox properly decode HEVC bitstreams when a single frame is split into multiple slice NALUs?​​ Key Observations: ​​1. Single-NALU frames​​ work fine. ​​2. Multi-NALU frames​​ (sliced I/P-frames) cause decoding failure. 3. The decoder session is created successfully (VTDecompressionSessionCreate returns no error).
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197
Activity
May ’25
Indicate Packet Loss With AVAudioConverter for OPUS Decoding
I'm using an AVAudioConverter object to decode an OPUS stream for VoIP. The decoding itself works well, however, whenever the stream stalls (no more audio packet is available to decode because of network instability) this can be heard in crackling / abrupt stop in decoded audio. OPUS can mitigate this by indicating packet loss by passing a null pointer in the C-library to int opus_decode_float (OpusDecoder * st, const unsigned char * data, opus_int32 len, float * pcm, int frame_size, int decode_fec), see https://opus-codec.org/docs/opus_api-1.2/group__opus__decoder.html#ga9c554b8c0214e24733a299fe53bb3bd2. However, with AVAudioConverter using Swift I'm constructing an AVAudioCompressedBuffer like so:         let compressedBuffer = AVAudioCompressedBuffer(             format: VoiceEncoder.Constants.networkFormat,             packetCapacity: 1,             maximumPacketSize: data.count         )         compressedBuffer.byteLength = UInt32(data.count)         compressedBuffer.packetCount = 1   compressedBuffer.packetDescriptions! .pointee.mDataByteSize = UInt32(data.count)         data.copyBytes(             to: compressedBuffer.data .assumingMemoryBound(to: UInt8.self),             count: data.count         ) where data: Data contains the raw OPUS frame to be decoded. How can I specify data loss in this context and cause the AVAudioConverter to output PCM data whenever no more input data is available? More context: I'm specifying the audio format like this:         static let frameSize: UInt32 = 960         static let sampleRate: Float64 = 48000.0         static var networkFormatStreamDescription = AudioStreamBasicDescription(             mSampleRate: sampleRate,             mFormatID: kAudioFormatOpus,             mFormatFlags: 0,             mBytesPerPacket: 0,             mFramesPerPacket: frameSize,             mBytesPerFrame: 0,             mChannelsPerFrame: 1,             mBitsPerChannel: 0,             mReserved: 0         )         static let networkFormat = AVAudioFormat( streamDescription: &networkFormatStreamDescription )! I've tried 1) setting byteLength and packetCount to zero and 2) returning nil but setting .haveData in the AVAudioConverterInputBlock I'm using with no success.
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1
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926
Activity
May ’25
401 Authorization error for Music Feed API
I've established proper authorization for general music api calls, but when I use that same authorization to retrieve metadata for the latest music feeds (see https://developer.apple.com/documentation/applemusicfeed/requesting-a-feed-export), I get a 401 Unauthorized error. As per the documentation, I'm simply issuing a GET against https://api.media.apple.com/v1/feed/album/latest. Are there different entitlements needed for the Music Feed API?
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2
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0
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109
Activity
May ’25
MusicKit playbackTime Accuracy
Hello, Has anyone else experienced variations in the accuracy of the playbackTime value? After a few seconds of playback, the reported time adjusts by a fraction of a second, making it difficult to calculate the actual playbackTime of the audio. This can be recreated by playing a song in MusicKit, recording the start time of the audio, playing for at least 10-20 seconds, and then comparing the playbackTime value to one calculated using the start time of the audio. In my experience this jump occurs after about 10 seconds of playback. Any help would be appreciated. Thanks!
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1
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0
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131
Activity
May ’25
H.265 Decoding with VideoToolBox
I am creating an app that decodes H.265 elementary streams on iOS. I use VideoToolBox to decode from H.265 to NV12. The decoded data is enqueued in the CMSampleBufferDisplayLayer as a CMSampleBuffer. However, nothing is displayed in the VideoPlayerView. It remains black. The decoding in VideoToolBox is successful. I confirmed this by saving the NV12 data in the CMSampleBuffer to a file and displaying it using a tool. Why is nothing displayed in the VideoPlayerView? I can provide other source code as well. // // ContentView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI struct ContentView: View { var body: some View { VStack { Text("H.265 Player (temp.h265)") .font(.headline) VideoPlayerView() .frame(width: 360, height: 640) // Adjust or make it responsive for iOS } .padding() } } #Preview { ContentView() } // // VideoPlayerView.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import SwiftUI import AVFoundation struct VideoPlayerView: UIViewRepresentable { // Return an H265Player as the coordinator, and start playback there. func makeCoordinator() -> H265Player { H265Player() } func makeUIView(context: Context) -> UIView { let uiView = UIView(frame: .zero) // Base layer for attaching sublayers uiView.backgroundColor = .black // Screen background color (for iOS) // Create the display layer and add it to uiView.layer let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.bounds displayLayer.backgroundColor = UIColor.clear.cgColor uiView.layer.addSublayer(displayLayer) // Start playback context.coordinator.startPlayback() return uiView } func updateUIView(_ uiView: UIView, context: Context) { // Reset the frame of the AVSampleBufferDisplayLayer when the view's size changes. let displayLayer = context.coordinator.displayLayer displayLayer.frame = uiView.layer.bounds // Optionally update the layer's background color, etc. uiView.backgroundColor = .black displayLayer.backgroundColor = UIColor.clear.cgColor // Flush transactions if necessary CATransaction.flush() } } // // H265Player.swift // H265Decoder // // Created by Kohshin Tokunaga on 2025/02/15. // import Foundation import AVFoundation import CoreMedia class H265Player: NSObject, VideoDecoderDelegate { let displayLayer = AVSampleBufferDisplayLayer() private var decoder: H265Decoder? override init() { super.init() // Initial configuration for the display layer displayLayer.videoGravity = .resizeAspect // Initialize the decoder (delegate = self) decoder = H265Decoder(delegate: self) // For simple playback, set isBaseline to true decoder?.isBaseline = true } func startPlayback() { // Load the file "cars_320x240.h265" guard let url = Bundle.main.url(forResource: "temp2", withExtension: "h265") else { print("File not found") return } do { let data = try Data(contentsOf: url) // Set FPS and video size as needed let packet = VideoPacket(data: data, type: .h265, fps: 30, videoSize: CGSize(width: 1080, height: 1920)) // Decode as a single packet decoder?.decodeOnePacket(packet) } catch { print("Failed to load file: \(error)") } } // MARK: - VideoDecoderDelegate func decodeOutput(video: CMSampleBuffer) { // When decoding is complete, send the output to AVSampleBufferDisplayLayer displayLayer.enqueue(video) } func decodeOutput(error: DecodeError) { print("Decoding error: \(error)") } }
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2
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728
Activity
May ’25
iOS AUv3 extension: no Icon shown in host
Hi, I'm working on an AUv3 project. The app itself displays my icon. However the Auv3 extension does not display any icon in any host app (AUM, Drambo, etc.0). I thought that the extension would inherit the host app icon but that it does not appear to be the case. I tried to add the icon as a 1024x1024 file to the extension target and the update my extension plist file withe a CFBundleIconFile key but no luck either. It must surely be really easy. What am I missing? Thanks in advance for your help!
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5
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0
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152
Activity
May ’25
how to enumerate build-in media devices?
Hello, I need to enumerate built-in media devices (cameras, microphones, etc.). For this purpose, I am using the CoreAudio and CoreMediaIO frameworks. According to the table 'Daemon-Safe Frameworks' in Apple’s TN2083, CoreAudio is daemon-safe. However, the documentation does not mention CoreMediaIO. Can CoreMediaIO be used in a daemon? If not, are there any documented alternatives to detect built-in cameras in a daemon (e.g., via device classes in IOKit)? Thank you in advance, Pavel
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0
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171
Activity
May ’25
SystemAudio Capture API Fails with OSStatus error 1852797029 (kAudioCodecIllegalOperationError)
Issue Description I'm implementing a system audio capture feature using AudioHardwareCreateProcessTap and AudioHardwareCreateAggregateDevice. The app successfully creates the tap and aggregate device, but when starting the IO procedure with AudioDeviceStart, it sometimes fails with OSStatus error 1852797029. (The operation couldn’t be completed. (OSStatus error 1852797029.)) The error occurs inconsistently, which makes it particularly difficult to debug and reproduce. Questions Has anyone encountered this intermittent "nope" error code (0x6e6f7065) when working with system audio capture? Are there specific conditions or system states that might trigger this error sporadically? Are there any known workarounds for handling this intermittent failure case? Any insights or guidance would be greatly appreciated. I'm wondering if anyone else has encountered this specific "nope" error code (0x6e6f7065) when working with system audio capture.
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0
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189
Activity
May ’25
Album parquet files don't include song names
The documentation of the Apple Music Feed API states that the Album object would include songs — a list of songs in the album. As per the doc, this would be an array of object Album.RelatedSong, which would include both an id and nameDefault. Unfortunately, the album parquet files only include the song id and not the name of the song itself. Please advise - is the documentation incorrect or are the recently posted parquet files in error?
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0
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88
Activity
May ’25
Invalid album IDs in parquet files
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.
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1
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131
Activity
May ’25
How to Get Device Orientation in Background (PiP) Mode?
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!
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76
Activity
May ’25
(iOS 18) SFSpeechRecognitionResult providing new text after a gap in speaking
Here is the demo from Apple's site This issues is specific to iOS 18. When running this demo, we are getting new text when we have a gap in speaking, the recognitionTask(with:resultHandler:) provides new text which is only spoken after the gap and not the concatenation of old text and the new spoken text.
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1.2k
Activity
May ’25
videoCaptureQueue would make the app crashed when I using IOS 18.4.1
Hi All I have some problem when I using the IOS 18.4.1 I have iphone16 pro and ipad Air, both are updated to IOS 18.4.1 I tried to following sample code. However, when I run the app around 30 seconds to 1 minutes, the application would be crashed When I using another Ipad with IOS 17, it would not have the same problem. https://developer.apple.com/documentation/createml/creating-an-action-classifier-model https://developer.apple.com/documentation/createml/detecting_human_actions_in_a_live_video_feed#overview%29,
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6
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242
Activity
May ’25
I’m using ScreenCaptureKit on macOS to grab frames and measure end-to-end latency (capture → my delegate callback). For each CMSampleBuffer I read:
I’m using ScreenCaptureKit on macOS to grab frames and measure end-to-end latency (capture → my delegate callback). For each CMSampleBuffer I read: let pts = CMSampleBufferGetPresentationTimeStamp(sampleBuffer).seconds to get the “capture” timestamp, and I also extract the mach-absolute display time: let attachments = CMSampleBufferGetSampleAttachmentsArray(sampleBuffer, createIfNecessary: false) as? [[SCStreamFrameInfo: Any]] let displayMach = attachments?.first?[.displayTime] as? UInt64 // convert mach ticks to seconds... Then I compare both against the current time: let now = CACurrentMediaTime() let latencyFromPTS = now - pts let latencyFromDisplay = now - displayTimeSeconds But I consistently see negative values for both calculations—i.e. the PTS or displayTime often end up numerically larger than now. This suggests that the “presentation timestamp” and the mach-absolute display time are coming from a different epoch or clock domain than CACurrentMediaTime(). Questions: Which clocks/epochs does ScreenCaptureKit use for PTS and for .displayTime? How can I align these timestamps with CACurrentMediaTime() so that now - pts and now - displayTime reliably yield non-negative real-world latencies? Any pointers on the correct clock conversions or APIs to use would be greatly appreciated.
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1
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204
Activity
May ’25
Tvos 18 (Show When Muted and Show on Skip Back)
Is there any way we can detect the status of the Show When Muted and Show on Skip Back device settings in code ?
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0
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1
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229
Activity
May ’25
AVAudioPlayer/SKAudioNode audio no longer plays after interruption
Hi 👋! We have a SpriteKit-based app where we play AVAudio sounds in three different ways: Effects (incl. UI sounds) with AVAudioPlayer. Long looping tracks with AVAudioPlayer. Short animation effects on the timeline of SpriteKit's SKScene files (effectively SKAudioNode nodes). We've found that when you exit the app or otherwise interrupt audio plays, future audio plays often fail. For example, there's a WebKit-based video trailer inside the app, and if you play it, our looping background music track (2.) will stop playing, and won't resume as you close the trailer (return from WebKit). This is probably due to us not manually restarting the track (so may well be easily fixed). Periodically played AVAudioPlayer audio (1.) are not affected. However, the more concerning thing is that the audio tracks on SKScene file timelines (3.) will no longer play. My hypothesis is that AVAudioEngine gets interrupted, and needs to be restarted for those AVAudioNode elements to regain functionality. Thing is, we don't deal with AVAudioEngine at all currently in the app, meaning it is never initiated to begin with. Obviously things return to normal when you remove the app from short-term memory and restart it. However, it seems many of our users aren't doing this, and often report audio failing presumably due to some interruption in the past without the app ever being cleared from memory. Any idea why timeline-run SKAudioNodes would fail like this? Should the app react to app backgrounding/foregrounding regarding audio? Any help would be very much appreciated ✌️!
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0
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204
Activity
May ’25
Mic audio before and after a call is answered
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?
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1
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75
Activity
May ’25
MPNowPlayingInfoCenter nowPlayingInfo throttled
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.
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4
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224
Activity
May ’25
Apple Music web player will not work on wkwebview web browser or electron chromium browser.
Hello, I'm trying to create a webbrowser but currently when signed into apple music webplayer I get the following message when I attempt to play on any versions of my webbrowser: Not available on the web You can listen to this in the Apple Music app. Is there a way to setup DRM (assuming this is the issue) with apple to allow my webbrowser to play this content? I believe Apple TV is also affected. Thank you ahead of time.
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0
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168
Activity
May ’25
Background audio player issue
I am work an app development on an app which request an audio function in background as an alert sound. during debug testing , the function work fine, but once I testing standalone without debugging , The function not work , it will play out the sound when I back to app. does any way to trace the issues ?
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0
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162
Activity
May ’25