Hi everyone! I’ve been working with AVFoundation and trying to use the AVMetricEventStreamPublisher to discover media performance metrics, as described in the Apple documentation. https://developer.apple.com/cn/videos/play/wwdc2024/10113/?time=508 However, when following the example code, I’m not getting the expected results. The performance metrics for both audio and video don’t seem to be captured properly. Has anyone successfully used this example code? If so, could you share your experience or any solutions you’ve found? Any tips or insights would be greatly appreciated. Thanks in advance! Ps. the example code: AVPlayerItem *item = ... AVMetricEventStream *eventStream = [AVMetricEventStream eventStream]; id subscriber = [[MyMetricSubscriber alloc] init]; [eventStream setSubscriber:subscriber queue:mySerialQueue] [eventStream subscribeToMetricEvent:[AVMetricPlayerItemLikelyToKeepUpEvent class]]; [eventStream subscribeToMetricEvent:[AVMetricPlayerItemPlaybackSummaryEvent class]]; [eventStream addPublisher:item];

the problem is when using HLS live stream with AVPlayer on iOS/ tvOS the player chooses first highest bandwidth then slowly steps down to lowest (within 1-3min) and eventually steps up again then repeats to step down. the AVPlayer error log sends events: errorStatusCode: -12888, errorDomain: Optional("CoreMediaErrorDomain"), errorComment: Optional("The operation couldn't be completed. (CoreMediaErrorDomain error -12888 - Playlist File unchanged for longer than 1.5 * target duration we use standard segments in CMAF format, 2sec duration #EXTM3U #EXT-X-VERSION:6 #EXT-X-TARGETDURATION:2 #EXT-X-MEDIA-SEQUENCE:147065903 #EXT-X-MAP:URI="video_1_4660000_init.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2" #EXT-X-PROGRAM-DATE-TIME:2025-04-30T12:51:07 #EXTINF:2.000, video_1_4660000_t17460174670001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2 #EXTINF:2.000, video_1_4660000_t17460174690001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2 #EXTINF:2.000, video_1_4660000_t17460174710001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2 when using 6sec segments the player stays stable at highest bandwidth. is there a way to avoid this error? in AVPlayer or HLS configuration?

TL;DR How to solve possible racing issue of EXT-X-SESSION-KEY request and encrypted media segment request? I'm having trouble using custom AVAssetResourceLoaderDelegate with video manifest containing VideoProtectionKey(VPK). My master manifest contains rendition manifest url and VPK url. When not using custom resource delegate, everything works fine. My custom resource delegate is implemented in way where it first append prefix to scheme of the master manifest url before creating the asset. And during handling master manifest, it puts back original scheme, make the request, modify the scheme for rendition manifest url in the response content by appending the same prefix again, so that rendition manifest request also goes into custom resource loader delegate. Same goes for VPK request. The AES-128 key is stored in memory within custom resource loader delegate object. So far so good. The VPK is requested before segment request. But the problem comes where the media segment requests happen. The media segment request url from rendition manifest goes into custom resource loader as well and those are encrypted. I can see segment request finish first then the related VPK requests kick in after a few seconds. The previous VPK value is cached in memory so it is not network causing the delay but some mechanism that I'm not aware of causing this. So could anyone tell me what would be the proper way of handling this situation? The native library is handling it well so I just want to know how. Thanks in advance!

Hi everyone, We’re currently developing a music-based app using MusicKit, and we recently noticed that iOS 26 beta introduces a new “Automix” feature in the Apple Music app. This enables seamless DJ-style transitions between songs—beyond the standard crossfade functionality. We’re trying to understand: Will this Automix feature be accessible to third-party apps that use MusicKit? If not available in the initial iOS 26 release, is there a plan to expose it through public APIs in a future update? Is there any technical documentation, WWDC session, or roadmap info regarding Automix support via MusicKit? This functionality would be a significant enhancement for our app, especially for intelligent audio transitions and curated playlists. Thanks.

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?

Hi everyone, I noticed that Apple recently added a few new beta sample codes related to video encoding: Encoding video for low-latency conferencing Encoding video for live streaming While experimenting with H.264 encoding, I came across some questions regarding certain configurations: When I enable kVTVideoEncoderSpecification_EnableLowLatencyRateControl, is it still possible to use kVTCompressionPropertyKey_VariableBitRate? In my tests, I get an error. It also seems that kVTVideoEncoderSpecification_EnableLowLatencyRateControl cannot be used together with kVTCompressionPropertyKey_ConstantBitRate when encoding H264. Is that expected? When using kVTCompressionPropertyKey_ConstantBitRate with kVTCompressionPropertyKey_MaxKeyFrameInterval set to 2, the encoder outputs only keyframes, and the frame size keeps increasing, which doesn’t seem like the intended behavior. Regarding the following code from the sample: let byteLimit = (Double(bitrate) / 8) * 1.5 as CFNumber let secLimit = Double(1.0) as CFNumber let limitsArray = [ byteLimit, secLimit ] as CFArray // Each 1 second limit byte as bitrate err = VTSessionSetProperty(session, key: kVTCompressionPropertyKey_DataRateLimits, value: limitsArray) This DataRateLimits setting doesn’t seem to have any effect in my tests. Whether I set it or not, the values remain unchanged. Since the documentation on developer.apple.com/documentation doesn’t clearly explain these cases, I’d like to ask if anyone has insights or recommendations about the proper usage of these settings. Thanks in advance!

The operation couldn’t be completed. (CoreMediaErrorDomain error -19156 - The operation couldn’t be completed. (CoreMediaErrorDomain error -19156.

Hello, We have Video Stream app. It has HLS VOD Content. We supply 1080p, 4K Contents to users. Users were watching 1080p content before tvOS 26. Users can not watch 1080p content anymore when they update to tvOS 26. We have not changed anything at HLS playlist side and application version. This problem only occurs on Apple TV 4th Gen (A1625) tvOS 26 version. There is no problem with newer Apple TV devices. Would you help to resolve problem? Thanks in advance

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

quotes are displayed incorrectly in subtitles of AVPlayerViewController when streaming VOD content using HLS. single quote ' (escaped ') is displayed as apos; double quotes " (escaped ") is displayed as quot; following the vtt specification. The same stream works fine in VLC player, showing quotes correctly in subtitles. subtitle vtt files use Content-Type: text/vtt WEBVTT X-TIMESTAMP-MAP=LOCAL:490014:06:04.000,MPEGTS:158764568760056 example line: 490014:05:46.000 --> 490014:05:50.440 align:start line:83% position:14% and the playlist has: #EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subs",LANGUAGE="da",NAME="Dansk",AUTOSELECT=YES,CHARACTERISTICS="public.accessibility.transcribes-spoken-dialog,public.accessibility.describes-music-and-sound",URI="subs/dan_5/playlist.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=780000,CODECS="mp4a.40.5,avc1.42c01e",RESOLUTION=256x144,AUDIO="audio-aac",SUBTITLES="subs" lære dig endnu bedre at kende." adding 'wvtt' to CODECS list in playlist does not make a difference. Is this a known bug? Is there a workaround? I guess the AVResourceLoaderDelegate can be used to intercept and parse the subtitle files, but it seems like quite a hack and not really intended to be used for this.

I'm developing a tutorial style tvOS app with multiple videos. The examples I've seen so far deal with only one video. Defining the player and source(url) before body view let avPlayer = AVPlayer(url: URL(string: "https://domain.com/.../.../video.mp4")!)) and then in the body view the video is displayed VideoPlayer(player: avPlayer) This allows options such as stop/start etc. When I try something similar with a video title passed into this view I can't define the player with this title variable. var vTitle: String var avPlayer = AVPlayer(url: URL(string: "https://domain.com/.../.../" + vTitle + ".mp4"")!)) var body: some View { I het an error that vTitle can't be used in the url above the body view. Any thoughts or suggestions? Thanks

I'm developing an iOS radio app that plays various HLS streams. The challenge is that some stations broadcast HLS streams containing both audio and video (example: https://svs.itworkscdn.net/smcwatarlive/smcwatar/chunks.m3u8), but I want to: Extract and play only the audio track Support AirPlay for audio-only streaming Minimize data usage by not downloading video content Technical Details: iOS 17+ Swift 5.9 Using AVFoundation for playback Current implementation uses AVPlayer with AVPlayerItem Current Code Structure: class StreamPlayer: ObservableObject { @Published var isPlaying = false private var player: AVPlayer? private var playerItem: AVPlayerItem? func playStream(url: URL) { let asset = AVURLAsset(url: url) playerItem = AVPlayerItem(asset: asset) player = AVPlayer(playerItem: playerItem) player?.play() } Stream Analysis: When analyzing the video stream using FFmpeg: CopyInput #0, hls, from 'https://svs.itworkscdn.net/smcwatarlive/smcwatar/chunks.m3u8': Stream #0:0: Video: h264, yuv420p(tv, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps Stream #0:1: Audio: aac, 44100 Hz, stereo, fltp Attempted Solutions: Using MobileFFmpeg: let command = [ "-i", streamUrl, "-vn", "-acodec", "aac", "-ac", "2", "-ar", "44100", "-b:a", "128k", "-f", "mpegts", "udp://127.0.0.1:12345" ].joined(separator: " ") ffmpegProcess = MobileFFmpeg.execute(command) Issue: While FFmpeg successfully extracts audio, playback through AVPlayer doesn't work reliably. Tried using HLS output: let command = [ "-i", streamUrl, "-vn", "-acodec", "aac", "-ac", "2", "-ar", "44100", "-b:a", "128k", "-f", "hls", "-hls_time", "2", "-hls_list_size", "3", outputUrl.path ] Issue: Creates temporary files but faces synchronization issues with live streams. Requirements: Real-time audio extraction from HLS stream Maintain live streaming capabilities Full AirPlay support Minimal data usage (avoid downloading video content) Handle network interruptions gracefully Questions: What's the most efficient way to extract only audio from an HLS stream in real-time? Is there a way to tell AVPlayer to ignore video tracks completely? Are there better alternatives to FFmpeg for this specific use case? What's the recommended approach for handling AirPlay with modified streams? Any guidance or alternative approaches would be greatly appreciated. Thank you!

Can some one please answer me How Can I update the cookies of the previously set m3u8 video in AVPlayer without creating the new AVURLAsset and replacing the AVPlayer current Item with it

ApplicationMusicPlayer with queue created from playlist crashes with random occurrence shortly after skipping back or forth using controls embedded in the notification, with the error on console log: applicationController: xpc service connection interrupted. I've noticed that the issue occurs more frequently the shorter is time between skipping entries. Since ApplicationMusicPlayer is run on a remote process, the main app does not crash, but the music stops playing without any exception, and the playback control turns uninitiated. Here is how I'm initiating the queue: let entries = playlist .with(.entries).entries! .map { ApplicationMusicPlayer.Queue.Entry($0) } ApplicationMusicPlayer.shared.queue = .init( entries, startingAt: entries.last ) Please give me some tips on how to solve this. EDIT: The issue does not occur when navigating quickly through the station.

In our Apple TV application, we are using the native AVPlayer for live playback functionality. During live restart playback, we intermittently encounter an error when the playback timeline approaches the actual live event end time. Error: The operation couldn’t be completed. (CoreMediaErrorDomain error -16839 - Unable to get playlist before long download timer) / Failure reason: Scenario: The live event is scheduled from 7:00 AM to 8:00 AM. Restart playback begins at 7:20 AM, allowing the user to watch the event from the start while the live stream continues in real-time. As the restart playback timeline approaches the actual event end time (8:00 AM), AVPlayer displays an error, and playback continues in the background.

Hi folks, When doing HLS v6 live streaming with fmp4 chunks we noticed that when the encoder timestamps slightly drift and a #EXT-X-DISCONTINUITY tag is created in either the audio or video playlist (in an ABR setup), the tag is not correctly handled by the player leading to a broken playback containing black screen or no audio (depending on which playlist the tag is printed in). We noticed that this is often true when the number of tags is odd between the playlists (eg. the audio playlist contains 1 tag and the video contains 2 tags will result in a black screen with audio). By using the same "broken" source but using Shaka player instead won't break the playback at all. Are there any possible fix (or upcoming) for AV Player?

I can't play video content with HEVC and DRM. Tested HEVC only: OK. Tested DRM+AVC: Ok. Tested 2 players (Clappr/Stevie and BitMovin) Master, variants and EXT-X-MAPs are downloaded Ok, DRM keys Ok and then, for instance with BitMovin Player: [BMP] [Player] [Error] Event: SourceError, Data: {"code":2001,"data":{"message":"The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.)","code":-12927},"message":"Source Error. The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.)","timestamp":1740320663.4505711,"type":"onSourceError"} code: 2001 [Data code: -12927, message: The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.), underlying error: Error Domain=CoreMediaErrorDomain Code=-12927 "(null)"] 4k-master.m3u8.txt 4k.m3u8.txt 4k-audio.m3u8.txt

Hello All, I am looking for assistance with our FairPlay Streaming (FPS) certificates. We are in the process of migrating to a new video streaming vendor and need to create a new FPS certificate using SDK 4. However, we have reached the limit of allowed FPS certificates in our account and cannot create a new one. Issue Details: • We currently have two FPS certificates active in our developer account. • One of these was created using SDK 5, but our new vendor (Mux) requires an FPS certificate based on SDK 4. • Since Apple does not allow deleting FPS certificates from the developer portal, we are unable to create a new SDK 4 certificate. • We kindly request Apple to revoke one of our existing FPS certificates to allow us to generate a new SDK 4 certificate. Request: We would greatly appreciate it if you could assist us on how to delete one of our existing FPS certificates so that we can proceed with creating a new SDK 4 certificate for our vendor integration. Thank you for your support.

Hello, I am developing a video streaming service that uses FairPlay. Since around February 20th, we have started receiving reports of CoreMediaErrorDomain -42709 errors. Unfortunately, there is no documentation from Apple that explains what this error means, so we are not sure how to address or fix the issue. Most of the users who reported this error are using iOS 18.2.1 and iOS 18.3.1. Could you please advise on what we should check or how we might resolve this error?

A few months ago, I had the opportunity to receive a 2018 iMac, and I’ve been using it to create content for my social media. I was truly impressed by the power of its processors. Even with this older model, I’ve been able to grow my presence online—something I couldn’t achieve with newer computers from other brands that I previously purchased. I would love to become a promoter of your brand in the gaming world. All I ask for is technological support with more recent equipment and a minimal payment for collaborating with you. I am genuinely interested in being part of your company and leveraging the potential and reputation of Apple to reach even greater heights.