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Deep dive into the technical specifications that influence seamless playback for streaming services, including bitrates, codecs, and caching mechanisms.

Streaming Documentation

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HLS CMAF playlist with multiple DRM changes
Hi Is it possible to have a playlist where I have a indication of a stream in clear, but then, someone started a DRM encrypted period and then someone turns it off. Can I just do the following (I've removed the video segments part, I'm just interested in the parts where I want notify the new drm region )? #EXT-X-MAP:URI="video_2_10000000_t17586401730000000_init.mp4" #EXT-X-KEY:METHOD=NONE ... #EXT-X-MAP:URI="video_2_10000000_t17587374640000000_init.mp4" #EXT-X-KEY:METHOD=SAMPLE-AES,URI="skd://5df0b36ac4bb4d0ff954a73b502ac332",KEYFORMAT="com.apple.streamingkeydelivery",KEYFORMATVERSIONS="1" ... #EXT-X-MAP:URI="video_2_10000000_t17587376740000000_init.mp4?" #EXT-X-KEY:METHOD=NONE Should I insert discontinuity tags or something else? Right now what I can observe is that I got some audio drops when I try to do this.
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635
Dec ’25
Query regarding migrating from Fairplay Streaming SDK version 4.5.4 to version 26
Our license service is based on version 4.5.4 and we make use of sample .c/.h files for building license service. We are told that version 4.5.4 is going to be deprecated in 2026 and we should migrate to latest SDK version 26. When explored the SDK, we noticed that only python and Swift based SDk is provided. Does Apple also provide C/C++ based SDK as it is going to easier for us to integrate. If yes, please share the SDK package and sample license service solution.
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305
Dec ’25
FairPlay Client Question
The ASk is used by the KSM to derive the dASk, which is then used to decrypt the SK...R1. If the only thing we give the client is the certificate, how does it encrypt the SK...R1 so the server is able to process it. Would be nice to know it it works generally, because I've been getting questions about it and can't provide a helpful answer. Thanks in advance.
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311
Jan ’26
What does CoreMediaErrorDomain code -15418 indicate during LL-HLS live playback?
Hello, I am currently developing a video player using Custom AVPlayer SDK and testing LL-HLS live streaming. I encountered a specific error, CoreMediaErrorDomain -15418, during playback. I have searched through the official documentation and the forums, but I could not find any information regarding this error code. I would like to inquire about the following: Description & Cause: What does the error code -15418 specifically represent in the context of CoreMedia and LL-HLS? Severity: Is this a critical error that halts playback, or is it merely a warning? Environment Details: iOS Version: iOS 26.2 Device: iPhone 15 Pro Max Stream Type: LL-HLS (Low-Latency HLS) Impact: Quality drops Any insights or references to documentation would be greatly appreciated. Thank you.
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448
Jan ’26
Crash when trying to get originatingRecipient
According to the documentation (https://developer.apple.com/documentation/avfoundation/avcontentkeyrequest/originatingrecipient?changes=_3&language=objc), starting with ios 18.4, I can get AVContentKeyRecipient from AVContentKeyRequest. But when I try to get it, I get a crash. What could be the issue? I want to note that I add the asset to the AVContentKeySession using the addContentKeyRecipient method (https://developer.apple.com/documentation/avfoundation/avcontentkeysession/addcontentkeyrecipient(_:)?changes=_3&language=objc).
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477
Feb ’26
Inquiry regarding CoreMediaErrorDomain Code=-12880 in LL-HLS playback
Hello, I am developing a custom player SDK based on AVPlayer. While testing LL-HLS streams, I intermittently encounter the following error: Error Domain=CoreMediaErrorDomain Code=-12880 Since I cannot find documentation for this specific code, could you please clarify its meaning? Specifically, I would like to know if this is a critical error that disrupts playback, or if it is just a warning that can be safely ignored. Any insights would be appreciated. Thank you.
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300
Feb ’26
Clarification on SPC Version 3 Availability and Requirements (SDK 26 Certificate Bundle)
Hello, I’m using a valid certificate bundle generated with SDK 26 (combined RSA‑1024 + RSA‑2048). However, all my devices currently still generate SPC v2 during playback, including my iPhone 16 under iOS 26.2. Apple staff mentioned that future iOS versions will send SPC v3 when using an SDK 26 certificate bundle. Could you please clarify: Which iOS/macOS versions will first support SPC v3? Are there any additional client‑side requirements (Safari version, playback APIs, headers, etc.) to trigger SPC v3? Is there any way to test SPC v3 today, e.g., using beta builds? Thank you!
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697
Feb ’26
The audio of FairPlay protected content can be captured - Safari on iOS
Hi, Has anyone been able to protect the audio part of FairPlay protected content from being captured as part of screen recording on Safari/iOS (PWA and/or online web app)? We have tried many things but could not prevent the audio from being recorded. Same app and content on Safari/Mac does not allow audio to be recorded. Any tips?
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618
Mar ’26
Inquiry regarding CoreMediaErrorDomain Code=-15517 during LL-HLS Live Playback
Hello, I am currently developing a live streaming application using AVPlayer to play LL-HLS (Low-Latency HLS) content. During our testing phase, we consistently encountered the following error in the logs: CoreMediaErrorDomain Code=-15517 The challenge we are facing is that the error description is quite vague. It only provides cryptic messages such as "Key not found" or "No value information," which makes it extremely difficult to identify the root cause or perform a deep-dive analysis. I have searched through the official Apple Developer documentation and technical notes, but I couldn’t find any specific reference to what Code -15517 signifies in the context of LL-HLS or CoreMedia. Regarding this issue, I have the following questions: What is the specific meaning of this error code (-15517)? Does it relate to missing tags in the HLS manifest, or is it an internal state issue within the AVPlayer stack? Specifically, I would like to know if this is a critical error that disrupts playback, or if it is just a warning that can be safely ignored. Is there any additional logging or debugging tool you would recommend to further investigate "Key not found" issues in LL-HLS? Any insights or guidance from the community or Apple engineers would be greatly appreciated. Thank you in advance for your help.
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394
Feb ’26
Swift Array Out of Bounds Crash in VTFrameProcessor when using VTLowLatencyFrameInterpolationParameters
Hi everyone, Our team is encountering a reproducible crash when using VTLowLatencyFrameInterpolation on iOS 26.3 while processing a live LL-HLS input stream. 🤖 Environment Device: iPhone 16 OS: iOS 26.3 Xcode: Xcode 26.3 Framework: VideoToolbox 💥 Crash Details The application crashes with the following fatal error: Fatal error: Swift/ContiguousArrayBuffer.swift:184: Array index out of range The stack trace highlights the following: VTLowLatencyFrameInterpolationImplementation processWithParameters:frameOutputHandler: Called from VTFrameProcessor.process(parameters:) Here is the simplified implementation block where the crash occurs. (Note: PrismSampleBuffer and PrismLLFIError are our internal custom wrapper types). // Create `VTFrameProcessorFrame` for the source (previous) frame. let sourcePTS = sourceSampleBuffer.presentationTimeStamp var sourceFrame: VTFrameProcessorFrame? if let pixelBuffer = sourceSampleBuffer.imageBuffer { sourceFrame = VTFrameProcessorFrame(buffer: pixelBuffer, presentationTimeStamp: sourcePTS) } // Validate the source VTFrameProcessorFrame. guard let sourceFrame else { throw PrismLLFIError.missingImageBuffer } // Create `VTFrameProcessorFrame` for the next frame. let nextPTS = nextSampleBuffer.presentationTimeStamp var nextFrame: VTFrameProcessorFrame? if let pixelBuffer = nextSampleBuffer.imageBuffer { nextFrame = VTFrameProcessorFrame(buffer: pixelBuffer, presentationTimeStamp: nextPTS) } // Validate the next VTFrameProcessorFrame. guard let nextFrame else { throw PrismLLFIError.missingImageBuffer } // Calculate interpolation intervals and allocate destination frame buffers. let intervals = interpolationIntervals() let destinationFrames = try framesBetween(firstPTS: sourcePTS, lastPTS: nextPTS, interpolationIntervals: intervals) let interpolationPhase: [Float] = intervals.map { Float($0) } // Create VTLowLatencyFrameInterpolationParameters. // This sets up the configuration required for temporal frame interpolation between the previous and current source frames. guard let parameters = VTLowLatencyFrameInterpolationParameters( sourceFrame: nextFrame, previousFrame: sourceFrame, interpolationPhase: interpolationPhase, destinationFrames: destinationFrames ) else { throw PrismLLFIError.failedToCreateParameters } try await send(sourceSampleBuffer) // Process the frames. // Using progressive callback here to get the next processed frame as soon as it's ready, // preventing the system from waiting for the entire batch to finish. for try await readOnlyFrame in self.frameProcessor.process(parameters: parameters) { // Create an interpolated sample buffer based on the output frame. let newSampleBuffer: PrismSampleBuffer = try readOnlyFrame.frame.withUnsafeBuffer { pixelBuffer in try PrismLowLatencyFrameInterpolation.createSampleBuffer(from: pixelBuffer, readOnlyFrame.timeStamp) } // Pass the newly generated frame to the output stream. try await send(newSampleBuffer) } 🙋 Questions Are there any known limitations or bugs regarding VTLowLatencyFrameInterpolation when handling live 60fps streams? Are there any undocumented constraints we should be aware of regarding source/previous frame timing, pixel buffer attributes, or how destinationFrames and interpolationPhase arrays must be allocated? Is a "warm-up" sequence recommended after startSession() before making the first process(parameters:) call?
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934
Mar ’26
On iOS 26, HLS alternate audio track selection behaves inconsistently
Summary On iOS 26, HLS alternate audio track selection behaves inconsistently on both VOD and live streams: the French track falls back to the DEFAULT=YES (English) track after manual selection, and in some cases switching to a non-default track appears to work but it is then impossible to switch back to English. Environment iOS version: 26 Players affected: native Safari on iOS 26 and THEOplayer (issue also reproducible on THEOplayer's own demo page) Stream type: HLS/CMAF with demuxed alternate audio renditions (CMFC container) Affected stream types: both VOD and live streaming Issue NOT present on iOS 17/18 Manifest #EXTM3U #EXT-X-VERSION:4 #EXT-X-INDEPENDENT-SEGMENTS #EXT-X-STREAM-INF:BANDWIDTH=8987973,AVERAGE-BANDWIDTH=8987973,VIDEO-RANGE=SDR,CODECS="avc1.640028",RESOLUTION=1920x1080,FRAME-RATE=29.970,AUDIO="program_audio" video_1080p.m3u8 #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="en",ASSOC-LANGUAGE="en",NAME="English",AUTOSELECT=YES,DEFAULT=YES,CHANNELS="2",URI="audio_ENG.m3u8" #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="de",ASSOC-LANGUAGE="de",NAME="Deutsch",AUTOSELECT=YES,DEFAULT=NO,CHANNELS="2",URI="audio_DEU.m3u8" #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="fr",ASSOC-LANGUAGE="fr",NAME="Francais",AUTOSELECT=YES,DEFAULT=NO,CHANNELS="2",URI="audio_FRA.m3u8" Steps to Reproduce Load the HLS manifest (VOD or live) in Safari on iOS 26, or in any AVFoundation-backed player Start playback — English plays correctly as DEFAULT Manually select "Francais" from the audio track selector Observe that English audio continues playing (French does not play) In a separate scenario: manually select "Deutsch" — German plays correctly Attempt to switch back to English — English does not resume; audio remains on the previously selected track Expected behavior Selecting any track should immediately switch to that language Switching back to English (DEFAULT=YES) should work at any time Behavior should be consistent across VOD and live streams Actual behavior Two distinct anomalies observed, reproducible on both VOD and live streams, in both native Safari and THEOplayer: French-specific fallback: selecting the French track causes playback to fall back to English. This does not happen with German. Cannot return to English: in cases where a non-default track plays correctly, attempting to switch back to the DEFAULT=YES track (English) fails — the previous non-default track continues playing. The fact that the issue reproduces in native Safari confirms this is an AVFoundation/WebKit-level regression, not a third-party player bug. What we have already verified and ruled out LANGUAGE codes are BCP-47 compliant (en, fr, de) ✓ EXT-X-VERSION:4 is present ✓ Audio codec removed from STREAM-INF CODECS (video-only) ✓ ASSOC-LANGUAGE attribute added matching LANGUAGE value ✓ Container metadata verified via ffprobe: mdhd box correctly contains language tags (e.g. "fra") ✓ Audio segment content verified via ffplay: correct audio in each language file ✓ French audio source file contains correct French audio content ✓ Issue reproduces in native Safari on iOS 26, confirming it is not a THEOplayer-specific bug Issue does NOT reproduce on iOS 17/18 with the same manifest and segments Additional notes The VOD stream is packaged with AWS MediaConvert, CMAF output group, SEGMENTED_FILES, AAC-LC codec (mp4a.40.2), 128kbps, 48kHz stereo. English uses AudioTrackType ALTERNATE_AUDIO_AUTO_SELECT_DEFAULT; French and German use ALTERNATE_AUDIO_AUTO_SELECT. The live stream uses AWS MediaPackage with a similar CMAF/HLS output configuration. Please advise whether this is a known regression in AVFoundation on iOS 26 and whether a fix is planned.
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566
Mar ’26
Generating a new FPS certificate (SDK 26) alongside an existing SDK 4 certificate
Hi, Our client currently has an FPS deployment certificate generated with SDK version 4 that is still actively used in production. They would like to generate an additional certificate using SDK version 26. Before doing so, they just want to confirm: Will the existing SDK 4 certificate remain unaffected and still visible in the Apple Developer portal? Any considerations they should keep in mind? Thanks! :)
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556
Mar ’26
AVContentKeySession: Cannot re-fetch content key once obtained — expected behavior?
We are developing a video streaming app that uses AVContentKeySession with FairPlay Streaming. Our implementation supports both online playback (non-persistable keys) and offline playback (persistable keys). We have observed the following behavior: Once a content key has been obtained for a given Content Key ID, AVContentKeySession does not trigger contentKeySession(_:didProvide:) again for that same Key ID We also attempted to explicitly call processContentKeyRequest(withIdentifier:initializationData:options:) on the session to force a new key request for the same identifier, but this did not result in the delegate callback being fired again. The session appears to consider the key already resolved and silently ignores the request. This means that if a user first plays content online (receiving a non-persistable key), and later wants to download the same content for offline use (requiring a persistable key), the delegate callback is not fired again, and we have no opportunity to request a persistable key. Questions Is this the expected behavior? Specifically, is it by design that AVContentKeySession caches the key for a given Key ID and does not re-request it — even when processContentKeyRequest(withIdentifier:) is explicitly called? Should we use distinct Content Key IDs for persistable vs. non-persistable keys? For example, if the same piece of content can be played both online and offline, is the recommended approach to have the server provide different EXT-X-KEY URIs (and thus different key identifiers) for the streaming and download variants? Is there a supported way to force a fresh key request for a Key ID that has already been resolved — for example, to upgrade from a non-persistable to a persistable key? Environment iOS 18+ AVContentKeySession(keySystem: .fairPlayStreaming) Any guidance on the recommended approach for supporting both streaming and offline playback for the same content would be greatly appreciated.
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584
Apr ’26
FairPlay SPC with an invalid device type
Hi, I received an SPC without a device Identity TLLV and with an invalid (i.e a value that is not specified in the FairPlay programming guide) value of device type in the Device info TLLV. The info I got is the following - Apple Device Type: Type:0x555ea482e2ef0a7c, OS version:189.121.178 Does anyone know what device type it is, and why it does not conform to the Apple spec? Also, should I accept such an SPC or is it not valid? Thanks.
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319
Apr ’26
FairPlay SPC v3 documentation mismatch: payload length field size vs sample code
Hi, I’ve identified a discrepancy between the FairPlay Streaming SPC v3 documentation and the provided Swift reference implementation regarding the SPC payload length field. Documentation states: The SPC V3 structure defines: SPC payload length: 4 bytes However, in Apple’s Swift sample implementation: // Move local offset by 12 to adjust for padding localOffset += 12 spcContainer.spcDataSize = Int(try readBigEndianU32(spc, localOffset)) This indicates: A 16-byte field (12 bytes padding + 4-byte length) This behavior also matches the SPC sample provided in the FairPlay Streaming SDK (sample_spc_v3.b64 ). 00000003 // spc version 00000000 // reserved .... 00000000000000000000000000000f40 // spc payload length (16 bytes) Could you please confirm the correct implementation? Thanks
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231
Apr ’26
HLS Tools - hlsreport critical error cause
Hi, I'm currently experiencing issues with HLS streams created by FFmpeg running on Safari. When I pass the stream to the mediastreamvalidator tool and then run hlsreport on the output, I get a critical error reported: Media Entry discontinuity value does not match previous playlist for MEDIA-SEQUENCE 1 If I let the stream finish (it's a live stream from an IoT device) and then perform the stream validation again I no longer receive the critical error. My assumption is that this critical error is contributing to the HLS stall on iOS. I have also noticed that if I let the stream continue and then re-load the video control in Safari the stream starts Is there a resource with explanations or remediation paths relevant to the possible output of the hlsreport? My m3u8 output looks like this (I have redacted the server host) #EXTM3U #EXT-X-VERSION:6 #EXT-X-TARGETDURATION:2 #EXT-X-MEDIA-SEQUENCE:1 #EXT-X-PLAYLIST-TYPE:EVENT #EXT-X-INDEPENDENT-SEGMENTS #EXT-X-DISCONTINUITY #EXTINF:2.000000, https://redacted.com/segment-00001.ts #EXTINF:2.000011, https://redacted.com/segment-00002.ts #EXTINF:2.000011, https://redacted.com/segment-00003.ts #EXTINF:2.000011, https://redacted.com/segment-00004.ts #EXTINF:2.000011, #EXT-X-ENDLIST Thanks for any advice or guidance possible - if I can provide isolated code snippets I will do. Andy
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829
May ’26
FairPlay multi key encryption in Safari on macOS
Is FairPlay multi key encryption supposed to work in Safari 26 on macOS? It stopped working for us some time last year. The very same content works on iOS in AVPlayer and single key encryption works fine. On macOS, the multi key content sometimes plays, sometimes not. It is as if there was some race condition on how fast the KSM responds with content keys. Very often, I can see just one KSM request in network console (instead of multiple for each video profile and audio) and the playback fails with Video error: code=3 msg=Media failed to decode. We've filed a Code Level Support ticket (19025185) and a bug report (FB22353469), but haven't really heard back. Just that engineering is actively investigating this issue, and was able to reproduce it.
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1d
Updating downloaded manifest
Following up on: https://feedbackassistant.apple.com/feedback/22501602 We have a downloaded .movpkg (via AVAggregateAssetDownloadTask) where we need to update #EXT-X-DATERANGE tag URLs in the manifest Apple Developer Technical Support (FB15965814) confirmed "it is perfectly fine to update the m3u8 playlist inside the movpkg if that works well for you." Can you confirm this is safe to rely on long-term and won't break in future OS updates? Is there anything we should watch out for (e.g., movpkg integrity checks, asset download storage manager interactions)?
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1d
How to detect if a HDR10+ variant is currently playing
Hi, We currently deliver HDR10+ content within a composite HLS stream where Dolby Vision is signaled as a supplemental codec alongside HDR10+. Our testing on Apple TV 4K (3rd generation) indicates that playback succeeds, but we have not found a reliable way to determine whether playback is occurring in Dolby Vision or HDR10+ mode when connected to a display that supports both formats. We have also verified that the same stream plays correctly on displays that support HDR10+ but do not support Dolby Vision. However, on displays that support both HDR10+ and Dolby Vision, we are unable to determine which dynamic range format AVPlayer ultimately selects. Is there a recommended Apple API or mechanism to determine whether AVPlayer is rendering content as HDR10+, Dolby Vision, or another HDR format at runtime? For reference, below is an example variant from our master playlist: #EXT-X-STREAM-INF:BANDWIDTH=2851276,AVERAGE-BANDWIDTH=2030750,CODECS="hvc1.2.4.L90.90,mp4a.40.2",SUPPLEMENTAL-CODECS="dvh1.08.01/dv1p,hvc1.2.4.L90.90/cdm4",RESOLUTION=854x480,FRAME-RATE=24,VIDEO-RANGE=PQ,HDCP-LEVEL=TYPE-1,CHARACTERISTICS="com.dss.cbcs.hdr.hd",AUDIO="aac-128k",SUBTITLES="sub-main" Specifically, we would like to understand: How AVPlayer chooses between Dolby Vision and HDR10+ when both are available in the same variant. Whether there is a supported way to determine the selected HDR format during playback. Whether any other APIs expose this information. Any guidance would be greatly appreciated. Thank you.
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4d
HLS CMAF playlist with multiple DRM changes
Hi Is it possible to have a playlist where I have a indication of a stream in clear, but then, someone started a DRM encrypted period and then someone turns it off. Can I just do the following (I've removed the video segments part, I'm just interested in the parts where I want notify the new drm region )? #EXT-X-MAP:URI="video_2_10000000_t17586401730000000_init.mp4" #EXT-X-KEY:METHOD=NONE ... #EXT-X-MAP:URI="video_2_10000000_t17587374640000000_init.mp4" #EXT-X-KEY:METHOD=SAMPLE-AES,URI="skd://5df0b36ac4bb4d0ff954a73b502ac332",KEYFORMAT="com.apple.streamingkeydelivery",KEYFORMATVERSIONS="1" ... #EXT-X-MAP:URI="video_2_10000000_t17587376740000000_init.mp4?" #EXT-X-KEY:METHOD=NONE Should I insert discontinuity tags or something else? Right now what I can observe is that I got some audio drops when I try to do this.
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1
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635
Activity
Dec ’25
Query regarding migrating from Fairplay Streaming SDK version 4.5.4 to version 26
Our license service is based on version 4.5.4 and we make use of sample .c/.h files for building license service. We are told that version 4.5.4 is going to be deprecated in 2026 and we should migrate to latest SDK version 26. When explored the SDK, we noticed that only python and Swift based SDk is provided. Does Apple also provide C/C++ based SDK as it is going to easier for us to integrate. If yes, please share the SDK package and sample license service solution.
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1
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0
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305
Activity
Dec ’25
Apple Vision Pro streaming spatial video transmission
I want develop an app for real-time streaming spatial video transmission from an Apple Vision Pro to another Apple Vision Pro and play, like MV-HEVC, does it's possible? If it's possible how to make it?
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1
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0
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335
Activity
May ’26
FairPlay Client Question
The ASk is used by the KSM to derive the dASk, which is then used to decrypt the SK...R1. If the only thing we give the client is the certificate, how does it encrypt the SK...R1 so the server is able to process it. Would be nice to know it it works generally, because I've been getting questions about it and can't provide a helpful answer. Thanks in advance.
Replies
1
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0
Views
311
Activity
Jan ’26
What does CoreMediaErrorDomain code -15418 indicate during LL-HLS live playback?
Hello, I am currently developing a video player using Custom AVPlayer SDK and testing LL-HLS live streaming. I encountered a specific error, CoreMediaErrorDomain -15418, during playback. I have searched through the official documentation and the forums, but I could not find any information regarding this error code. I would like to inquire about the following: Description & Cause: What does the error code -15418 specifically represent in the context of CoreMedia and LL-HLS? Severity: Is this a critical error that halts playback, or is it merely a warning? Environment Details: iOS Version: iOS 26.2 Device: iPhone 15 Pro Max Stream Type: LL-HLS (Low-Latency HLS) Impact: Quality drops Any insights or references to documentation would be greatly appreciated. Thank you.
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1
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0
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448
Activity
Jan ’26
Crash when trying to get originatingRecipient
According to the documentation (https://developer.apple.com/documentation/avfoundation/avcontentkeyrequest/originatingrecipient?changes=_3&language=objc), starting with ios 18.4, I can get AVContentKeyRecipient from AVContentKeyRequest. But when I try to get it, I get a crash. What could be the issue? I want to note that I add the asset to the AVContentKeySession using the addContentKeyRecipient method (https://developer.apple.com/documentation/avfoundation/avcontentkeysession/addcontentkeyrecipient(_:)?changes=_3&language=objc).
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1
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0
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477
Activity
Feb ’26
Inquiry regarding CoreMediaErrorDomain Code=-12880 in LL-HLS playback
Hello, I am developing a custom player SDK based on AVPlayer. While testing LL-HLS streams, I intermittently encounter the following error: Error Domain=CoreMediaErrorDomain Code=-12880 Since I cannot find documentation for this specific code, could you please clarify its meaning? Specifically, I would like to know if this is a critical error that disrupts playback, or if it is just a warning that can be safely ignored. Any insights would be appreciated. Thank you.
Replies
1
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0
Views
300
Activity
Feb ’26
Clarification on SPC Version 3 Availability and Requirements (SDK 26 Certificate Bundle)
Hello, I’m using a valid certificate bundle generated with SDK 26 (combined RSA‑1024 + RSA‑2048). However, all my devices currently still generate SPC v2 during playback, including my iPhone 16 under iOS 26.2. Apple staff mentioned that future iOS versions will send SPC v3 when using an SDK 26 certificate bundle. Could you please clarify: Which iOS/macOS versions will first support SPC v3? Are there any additional client‑side requirements (Safari version, playback APIs, headers, etc.) to trigger SPC v3? Is there any way to test SPC v3 today, e.g., using beta builds? Thank you!
Replies
1
Boosts
1
Views
697
Activity
Feb ’26
The audio of FairPlay protected content can be captured - Safari on iOS
Hi, Has anyone been able to protect the audio part of FairPlay protected content from being captured as part of screen recording on Safari/iOS (PWA and/or online web app)? We have tried many things but could not prevent the audio from being recorded. Same app and content on Safari/Mac does not allow audio to be recorded. Any tips?
Replies
1
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0
Views
618
Activity
Mar ’26
Inquiry regarding CoreMediaErrorDomain Code=-15517 during LL-HLS Live Playback
Hello, I am currently developing a live streaming application using AVPlayer to play LL-HLS (Low-Latency HLS) content. During our testing phase, we consistently encountered the following error in the logs: CoreMediaErrorDomain Code=-15517 The challenge we are facing is that the error description is quite vague. It only provides cryptic messages such as "Key not found" or "No value information," which makes it extremely difficult to identify the root cause or perform a deep-dive analysis. I have searched through the official Apple Developer documentation and technical notes, but I couldn’t find any specific reference to what Code -15517 signifies in the context of LL-HLS or CoreMedia. Regarding this issue, I have the following questions: What is the specific meaning of this error code (-15517)? Does it relate to missing tags in the HLS manifest, or is it an internal state issue within the AVPlayer stack? Specifically, I would like to know if this is a critical error that disrupts playback, or if it is just a warning that can be safely ignored. Is there any additional logging or debugging tool you would recommend to further investigate "Key not found" issues in LL-HLS? Any insights or guidance from the community or Apple engineers would be greatly appreciated. Thank you in advance for your help.
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1
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0
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394
Activity
Feb ’26
Swift Array Out of Bounds Crash in VTFrameProcessor when using VTLowLatencyFrameInterpolationParameters
Hi everyone, Our team is encountering a reproducible crash when using VTLowLatencyFrameInterpolation on iOS 26.3 while processing a live LL-HLS input stream. 🤖 Environment Device: iPhone 16 OS: iOS 26.3 Xcode: Xcode 26.3 Framework: VideoToolbox 💥 Crash Details The application crashes with the following fatal error: Fatal error: Swift/ContiguousArrayBuffer.swift:184: Array index out of range The stack trace highlights the following: VTLowLatencyFrameInterpolationImplementation processWithParameters:frameOutputHandler: Called from VTFrameProcessor.process(parameters:) Here is the simplified implementation block where the crash occurs. (Note: PrismSampleBuffer and PrismLLFIError are our internal custom wrapper types). // Create `VTFrameProcessorFrame` for the source (previous) frame. let sourcePTS = sourceSampleBuffer.presentationTimeStamp var sourceFrame: VTFrameProcessorFrame? if let pixelBuffer = sourceSampleBuffer.imageBuffer { sourceFrame = VTFrameProcessorFrame(buffer: pixelBuffer, presentationTimeStamp: sourcePTS) } // Validate the source VTFrameProcessorFrame. guard let sourceFrame else { throw PrismLLFIError.missingImageBuffer } // Create `VTFrameProcessorFrame` for the next frame. let nextPTS = nextSampleBuffer.presentationTimeStamp var nextFrame: VTFrameProcessorFrame? if let pixelBuffer = nextSampleBuffer.imageBuffer { nextFrame = VTFrameProcessorFrame(buffer: pixelBuffer, presentationTimeStamp: nextPTS) } // Validate the next VTFrameProcessorFrame. guard let nextFrame else { throw PrismLLFIError.missingImageBuffer } // Calculate interpolation intervals and allocate destination frame buffers. let intervals = interpolationIntervals() let destinationFrames = try framesBetween(firstPTS: sourcePTS, lastPTS: nextPTS, interpolationIntervals: intervals) let interpolationPhase: [Float] = intervals.map { Float($0) } // Create VTLowLatencyFrameInterpolationParameters. // This sets up the configuration required for temporal frame interpolation between the previous and current source frames. guard let parameters = VTLowLatencyFrameInterpolationParameters( sourceFrame: nextFrame, previousFrame: sourceFrame, interpolationPhase: interpolationPhase, destinationFrames: destinationFrames ) else { throw PrismLLFIError.failedToCreateParameters } try await send(sourceSampleBuffer) // Process the frames. // Using progressive callback here to get the next processed frame as soon as it's ready, // preventing the system from waiting for the entire batch to finish. for try await readOnlyFrame in self.frameProcessor.process(parameters: parameters) { // Create an interpolated sample buffer based on the output frame. let newSampleBuffer: PrismSampleBuffer = try readOnlyFrame.frame.withUnsafeBuffer { pixelBuffer in try PrismLowLatencyFrameInterpolation.createSampleBuffer(from: pixelBuffer, readOnlyFrame.timeStamp) } // Pass the newly generated frame to the output stream. try await send(newSampleBuffer) } 🙋 Questions Are there any known limitations or bugs regarding VTLowLatencyFrameInterpolation when handling live 60fps streams? Are there any undocumented constraints we should be aware of regarding source/previous frame timing, pixel buffer attributes, or how destinationFrames and interpolationPhase arrays must be allocated? Is a "warm-up" sequence recommended after startSession() before making the first process(parameters:) call?
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Mar ’26
On iOS 26, HLS alternate audio track selection behaves inconsistently
Summary On iOS 26, HLS alternate audio track selection behaves inconsistently on both VOD and live streams: the French track falls back to the DEFAULT=YES (English) track after manual selection, and in some cases switching to a non-default track appears to work but it is then impossible to switch back to English. Environment iOS version: 26 Players affected: native Safari on iOS 26 and THEOplayer (issue also reproducible on THEOplayer's own demo page) Stream type: HLS/CMAF with demuxed alternate audio renditions (CMFC container) Affected stream types: both VOD and live streaming Issue NOT present on iOS 17/18 Manifest #EXTM3U #EXT-X-VERSION:4 #EXT-X-INDEPENDENT-SEGMENTS #EXT-X-STREAM-INF:BANDWIDTH=8987973,AVERAGE-BANDWIDTH=8987973,VIDEO-RANGE=SDR,CODECS="avc1.640028",RESOLUTION=1920x1080,FRAME-RATE=29.970,AUDIO="program_audio" video_1080p.m3u8 #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="en",ASSOC-LANGUAGE="en",NAME="English",AUTOSELECT=YES,DEFAULT=YES,CHANNELS="2",URI="audio_ENG.m3u8" #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="de",ASSOC-LANGUAGE="de",NAME="Deutsch",AUTOSELECT=YES,DEFAULT=NO,CHANNELS="2",URI="audio_DEU.m3u8" #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="program_audio",LANGUAGE="fr",ASSOC-LANGUAGE="fr",NAME="Francais",AUTOSELECT=YES,DEFAULT=NO,CHANNELS="2",URI="audio_FRA.m3u8" Steps to Reproduce Load the HLS manifest (VOD or live) in Safari on iOS 26, or in any AVFoundation-backed player Start playback — English plays correctly as DEFAULT Manually select "Francais" from the audio track selector Observe that English audio continues playing (French does not play) In a separate scenario: manually select "Deutsch" — German plays correctly Attempt to switch back to English — English does not resume; audio remains on the previously selected track Expected behavior Selecting any track should immediately switch to that language Switching back to English (DEFAULT=YES) should work at any time Behavior should be consistent across VOD and live streams Actual behavior Two distinct anomalies observed, reproducible on both VOD and live streams, in both native Safari and THEOplayer: French-specific fallback: selecting the French track causes playback to fall back to English. This does not happen with German. Cannot return to English: in cases where a non-default track plays correctly, attempting to switch back to the DEFAULT=YES track (English) fails — the previous non-default track continues playing. The fact that the issue reproduces in native Safari confirms this is an AVFoundation/WebKit-level regression, not a third-party player bug. What we have already verified and ruled out LANGUAGE codes are BCP-47 compliant (en, fr, de) ✓ EXT-X-VERSION:4 is present ✓ Audio codec removed from STREAM-INF CODECS (video-only) ✓ ASSOC-LANGUAGE attribute added matching LANGUAGE value ✓ Container metadata verified via ffprobe: mdhd box correctly contains language tags (e.g. "fra") ✓ Audio segment content verified via ffplay: correct audio in each language file ✓ French audio source file contains correct French audio content ✓ Issue reproduces in native Safari on iOS 26, confirming it is not a THEOplayer-specific bug Issue does NOT reproduce on iOS 17/18 with the same manifest and segments Additional notes The VOD stream is packaged with AWS MediaConvert, CMAF output group, SEGMENTED_FILES, AAC-LC codec (mp4a.40.2), 128kbps, 48kHz stereo. English uses AudioTrackType ALTERNATE_AUDIO_AUTO_SELECT_DEFAULT; French and German use ALTERNATE_AUDIO_AUTO_SELECT. The live stream uses AWS MediaPackage with a similar CMAF/HLS output configuration. Please advise whether this is a known regression in AVFoundation on iOS 26 and whether a fix is planned.
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Mar ’26
Generating a new FPS certificate (SDK 26) alongside an existing SDK 4 certificate
Hi, Our client currently has an FPS deployment certificate generated with SDK version 4 that is still actively used in production. They would like to generate an additional certificate using SDK version 26. Before doing so, they just want to confirm: Will the existing SDK 4 certificate remain unaffected and still visible in the Apple Developer portal? Any considerations they should keep in mind? Thanks! :)
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556
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Mar ’26
AVContentKeySession: Cannot re-fetch content key once obtained — expected behavior?
We are developing a video streaming app that uses AVContentKeySession with FairPlay Streaming. Our implementation supports both online playback (non-persistable keys) and offline playback (persistable keys). We have observed the following behavior: Once a content key has been obtained for a given Content Key ID, AVContentKeySession does not trigger contentKeySession(_:didProvide:) again for that same Key ID We also attempted to explicitly call processContentKeyRequest(withIdentifier:initializationData:options:) on the session to force a new key request for the same identifier, but this did not result in the delegate callback being fired again. The session appears to consider the key already resolved and silently ignores the request. This means that if a user first plays content online (receiving a non-persistable key), and later wants to download the same content for offline use (requiring a persistable key), the delegate callback is not fired again, and we have no opportunity to request a persistable key. Questions Is this the expected behavior? Specifically, is it by design that AVContentKeySession caches the key for a given Key ID and does not re-request it — even when processContentKeyRequest(withIdentifier:) is explicitly called? Should we use distinct Content Key IDs for persistable vs. non-persistable keys? For example, if the same piece of content can be played both online and offline, is the recommended approach to have the server provide different EXT-X-KEY URIs (and thus different key identifiers) for the streaming and download variants? Is there a supported way to force a fresh key request for a Key ID that has already been resolved — for example, to upgrade from a non-persistable to a persistable key? Environment iOS 18+ AVContentKeySession(keySystem: .fairPlayStreaming) Any guidance on the recommended approach for supporting both streaming and offline playback for the same content would be greatly appreciated.
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584
Activity
Apr ’26
FairPlay SPC with an invalid device type
Hi, I received an SPC without a device Identity TLLV and with an invalid (i.e a value that is not specified in the FairPlay programming guide) value of device type in the Device info TLLV. The info I got is the following - Apple Device Type: Type:0x555ea482e2ef0a7c, OS version:189.121.178 Does anyone know what device type it is, and why it does not conform to the Apple spec? Also, should I accept such an SPC or is it not valid? Thanks.
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319
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Apr ’26
FairPlay SPC v3 documentation mismatch: payload length field size vs sample code
Hi, I’ve identified a discrepancy between the FairPlay Streaming SPC v3 documentation and the provided Swift reference implementation regarding the SPC payload length field. Documentation states: The SPC V3 structure defines: SPC payload length: 4 bytes However, in Apple’s Swift sample implementation: // Move local offset by 12 to adjust for padding localOffset += 12 spcContainer.spcDataSize = Int(try readBigEndianU32(spc, localOffset)) This indicates: A 16-byte field (12 bytes padding + 4-byte length) This behavior also matches the SPC sample provided in the FairPlay Streaming SDK (sample_spc_v3.b64 ). 00000003 // spc version 00000000 // reserved .... 00000000000000000000000000000f40 // spc payload length (16 bytes) Could you please confirm the correct implementation? Thanks
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231
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Apr ’26
HLS Tools - hlsreport critical error cause
Hi, I'm currently experiencing issues with HLS streams created by FFmpeg running on Safari. When I pass the stream to the mediastreamvalidator tool and then run hlsreport on the output, I get a critical error reported: Media Entry discontinuity value does not match previous playlist for MEDIA-SEQUENCE 1 If I let the stream finish (it's a live stream from an IoT device) and then perform the stream validation again I no longer receive the critical error. My assumption is that this critical error is contributing to the HLS stall on iOS. I have also noticed that if I let the stream continue and then re-load the video control in Safari the stream starts Is there a resource with explanations or remediation paths relevant to the possible output of the hlsreport? My m3u8 output looks like this (I have redacted the server host) #EXTM3U #EXT-X-VERSION:6 #EXT-X-TARGETDURATION:2 #EXT-X-MEDIA-SEQUENCE:1 #EXT-X-PLAYLIST-TYPE:EVENT #EXT-X-INDEPENDENT-SEGMENTS #EXT-X-DISCONTINUITY #EXTINF:2.000000, https://redacted.com/segment-00001.ts #EXTINF:2.000011, https://redacted.com/segment-00002.ts #EXTINF:2.000011, https://redacted.com/segment-00003.ts #EXTINF:2.000011, https://redacted.com/segment-00004.ts #EXTINF:2.000011, #EXT-X-ENDLIST Thanks for any advice or guidance possible - if I can provide isolated code snippets I will do. Andy
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May ’26
FairPlay multi key encryption in Safari on macOS
Is FairPlay multi key encryption supposed to work in Safari 26 on macOS? It stopped working for us some time last year. The very same content works on iOS in AVPlayer and single key encryption works fine. On macOS, the multi key content sometimes plays, sometimes not. It is as if there was some race condition on how fast the KSM responds with content keys. Very often, I can see just one KSM request in network console (instead of multiple for each video profile and audio) and the playback fails with Video error: code=3 msg=Media failed to decode. We've filed a Code Level Support ticket (19025185) and a bug report (FB22353469), but haven't really heard back. Just that engineering is actively investigating this issue, and was able to reproduce it.
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1d
Updating downloaded manifest
Following up on: https://feedbackassistant.apple.com/feedback/22501602 We have a downloaded .movpkg (via AVAggregateAssetDownloadTask) where we need to update #EXT-X-DATERANGE tag URLs in the manifest Apple Developer Technical Support (FB15965814) confirmed "it is perfectly fine to update the m3u8 playlist inside the movpkg if that works well for you." Can you confirm this is safe to rely on long-term and won't break in future OS updates? Is there anything we should watch out for (e.g., movpkg integrity checks, asset download storage manager interactions)?
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1d
How to detect if a HDR10+ variant is currently playing
Hi, We currently deliver HDR10+ content within a composite HLS stream where Dolby Vision is signaled as a supplemental codec alongside HDR10+. Our testing on Apple TV 4K (3rd generation) indicates that playback succeeds, but we have not found a reliable way to determine whether playback is occurring in Dolby Vision or HDR10+ mode when connected to a display that supports both formats. We have also verified that the same stream plays correctly on displays that support HDR10+ but do not support Dolby Vision. However, on displays that support both HDR10+ and Dolby Vision, we are unable to determine which dynamic range format AVPlayer ultimately selects. Is there a recommended Apple API or mechanism to determine whether AVPlayer is rendering content as HDR10+, Dolby Vision, or another HDR format at runtime? For reference, below is an example variant from our master playlist: #EXT-X-STREAM-INF:BANDWIDTH=2851276,AVERAGE-BANDWIDTH=2030750,CODECS="hvc1.2.4.L90.90,mp4a.40.2",SUPPLEMENTAL-CODECS="dvh1.08.01/dv1p,hvc1.2.4.L90.90/cdm4",RESOLUTION=854x480,FRAME-RATE=24,VIDEO-RANGE=PQ,HDCP-LEVEL=TYPE-1,CHARACTERISTICS="com.dss.cbcs.hdr.hd",AUDIO="aac-128k",SUBTITLES="sub-main" Specifically, we would like to understand: How AVPlayer chooses between Dolby Vision and HDR10+ when both are available in the same variant. Whether there is a supported way to determine the selected HDR format during playback. Whether any other APIs expose this information. Any guidance would be greatly appreciated. Thank you.
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4d