Is it possible to perform speech-to-text using AVAudioEngine to capture microphone input while being on a FaceTime call at the same time?
I tried implementing this, but whenever I attempt to start the AVAudioEngine while a FaceTime call is active, I get the following error:
“The operation couldn’t be completed. (OSStatus error 2003329396)”
I assume this might be due to microphone resource restrictions during FaceTime, but I’d like to confirm whether this limitation is at the system level or if there’s any possible workaround or entitlement that allows concurrent microphone access.
Has anyone encountered this issue or found a solution?
Speech
RSS for tagRecognize spoken words in recorded or live audio using Speech.
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I'm using the new SpeechAnalyzer framework to detect certain commands and want to improve accuracy by giving context. Seems like AnalysisContext is the solution for this, but couldn't find any usage example. So I want to make sure that I'm doing it right or not.
let context = AnalysisContext()
context.contextualStrings = [
AnalysisContext.ContextualStringsTag("commands"): [
"set speed level",
"set jump level",
"increase speed",
"decrease speed",
...
],
AnalysisContext.ContextualStringsTag("vocabulary"): [
"speed", "jump", ...
]
]
try await analyzer.setContext(context)
With this implementation, it still gives outputs like "Set some speed level", "It's speed level", etc.
Also, is it possible to make it expect number after those commands, in order to eliminate results like "set some speed level to" (instead of two).
Hello,
I want to use the Speech framework in my app. However, I found that if I want it to work offline, it must be downloaded separately on the device. Do I understand correctly that it is not allowed to use it in a Swift Student Challenge submission if English (as the speech language) must be downloaded by the tester on their device using the internet beforehand?
Hello! I would like to use Speech Framework on my App Playground for this year challenge. But I still can't understand if I am allowed to use it to respect the rule of "not rely on a network connection". That's why:
Speech framework can use on-device Speech recognition –
No internet connection needed ✅.
But it can ask to download an Apple's native language package to use it for this on-device recognition – To get this, you need to be connected to the Internet ❌.
When I try to add a Speech Recognition Capabilities on my App Playground, its' description says: "Required to perform speech recognition using Apple's servers." (screenshot is attached). Does it mean that I won't be able to use on-device recognition on my App Playground? – And therefore, only online-version of this framework is available and I can't use it to participate on the challenge successfully❓.
If it's possible, could you please make it clearer? This framework is crucial for my App Playground and I really need this to make it work.
Thanks for your help in advance! And a have a good day!
I am a graduate student conducting research in speech/audio signal processing and multimodal interaction.
Apple Vision Pro is widely recognized as a multimodal interactive system supporting voice, eye, and gesture inputs. However, I could not find detailed specifications or documentation about the audio input sampling rate used by the device’s built-in microphone array when capturing user audio.
Specifically, I would like to understand:
What is the default audio input sampling rate (e.g., 16 kHz, 44.1 kHz, 48 kHz, etc.) for the Vision Pro’s microphones?
When developing with visionOS / AVAudioSession / AVAudioEngine, is there a documented or recommended sampling rate for audio capture?
Are there any best practices or settings for enabling high-quality voice capture on Vision Pro (especially for voice research tasks)?
For context, my work involves voice processing, analysis, and possibly on-device real-time speech recognition. Any pointers to relevant APIs, documentation or examples (especially regarding audio capture buffer size or available formats on visionOS) would be very helpful.
Thank you in advance!
Best regards.
Apple provides a function to create TTS voice as a file in TTS.
(AVSpeechUtterance/AVSpeechSynthesizer)
Or, if the user records the video of TTS playback and uses that video
I wonder what the scope of use is if I use this TTS voice to make YouTube, TikTok, or commercial videos.
Is it impossible to use it commercially at all?
Can I use it commercially with the source indicated?
Can I use it commercially without a separate source indication?
Is there a difference in commercial use license between Siri voices and regular TTS voices?
Hello,
I am building an iOS-only, commercial app that uses AVSpeechSynthesizer with system voices, strictly using the APIs provided by Apple. Before distributing the app, I want to ensure that my current implementation does not conflict with the iOS Software License Agreement (SLA) and is aligned with Apple’s intended usage.
For a better playback experience (more accurate estimation of utterance duration and smoother skip forward/backward during playback), I currently synthesize speech using:
AVSpeechSynthesizer.write(_:toBufferCallback:)
Converting the received AVAudioPCMBuffer buffers into audio data
Storing the audio inside the app sandbox
Playing it back using AVAudioPlayer / AVAudioEngine
The cached audio is:
Generated fully on-device using system voices
Stored only inside the app’s private container
Used only for internal playback controls (timeline, seek, skip ±5 seconds)
Never shared, exported, uploaded, or exposed outside the app
The alternative approaches would be:
Keeping the generated audio entirely in memory (RAM) for playback purposes, without writing it to the file system at any point
Or using AVSpeechSynthesizer.speak(_:) and playing speech strictly in real time which has a poorer user experience compared to my approach
I have reviewed the current iOS Software License Agreement:
https://www.apple.com/legal/sla/docs/iOS18_iPadOS18.pdf
In particular, section (f) mentions restrictions around System Characters, Live Captions, and Personal Voice, including the following excerpt:
“…use … only for your personal, non-commercial use…
No other creation or use of the System Characters, Live Captions, or Personal Voice is permitted by this License, including but not limited to the use, reproduction, display, performance, recording, publishing or redistribution in a … commercial context.”
I do not see a specific reference in the SLA to system text-to-speech voices used via AVSpeechSynthesizer, and I want to be certain that temporarily caching synthesized speech for internal, non-exported playback is acceptable in a commercial app.
My question is:
Is caching AVSpeechSynthesizer system-voice output inside the app sandbox for internal playback acceptable, or is Apple’s recommended approach to rely only on real-time playback (speak(_:)) or strictly in-memory buffering without file storage?
If this question falls outside DTS technical scope and is instead a policy or licensing matter, I would appreciate guidance on the authoritative Apple documentation or the correct Apple team/contact.
Thank you.
I am trying to use the new SpeechAnalyzer framework in my Mac app, and am running into an issue for some languages.
When I call AssetInstallationRequest.downloadAndInstall() for some languages, it throws an error:
Error Domain=SFSpeechErrorDomain Code=1 "transcription.ar asset not found after attempted download."
The ".ar" appears to be the language code, which in this case was Arabic.
When I call AssetInventory.status(forModules:) before attempting the download, it is giving me a status of "downloading" (perhaps from an earlier attempt?). If this language was completely unsupported, I would expect it to return a status of "unsupported", so I'm not sure what's going on here.
For other languages (Polish, for example) SpeechTranscriber.supportedLocale(equivalentTo:) is returning nil, so that seems like a clearly unsupported language. But I can't tell if the languages I'm trying, like Arabic, are supported and something is going wrong, or if this error represents something I can work around.
Here's the relevant section of code. The error is thrown from downloadAndInstall(), so I never even get as far as setting up the SpeechAnalyzer itself.
private func setUpAnalyzer() async throws {
guard let sourceLanguage else {
throw Error.languageNotSpecified
}
guard let locale = await SpeechTranscriber.supportedLocale(equivalentTo: Locale(identifier: sourceLanguage.rawValue)) else {
throw Error.unsupportedLanguage
}
let transcriber = SpeechTranscriber(locale: locale, preset: .progressiveTranscription)
self.transcriber = transcriber
let reservedLocales = await AssetInventory.reservedLocales
if !reservedLocales.contains(locale) && reservedLocales.count == AssetInventory.maximumReservedLocales {
if let oldest = reservedLocales.last {
await AssetInventory.release(reservedLocale: oldest)
}
}
do {
let status = await AssetInventory.status(forModules: [transcriber])
print("status: \(status)")
if let installationRequest = try await AssetInventory.assetInstallationRequest(supporting: [transcriber]) {
try await installationRequest.downloadAndInstall()
}
}
...
Hello All,
I want to implement Text-to-Speech (TTS) and vibration functionality when a push notification arrives. In my app, I am already using Critical Alerts, and the critical alert sound plays correctly in all app states.
However, I need to confirm whether it is possible to trigger Text-to-Speech and custom vibration in all app states:
Foreground
Background
Terminated (killed) state
My Questions:
Is it technically possible for iOS to run Text-to-Speech (using AVSpeechSynthesizer) when a critical alert notification arrives in background or terminated state?
Is it possible to trigger custom vibration patterns from a critical alert when the app is not running?
If yes, can someone please provide guidance or sample code on how to implement this?
If no, can Apple explain the limitation or provide documentation confirming that TTS and vibration cannot be triggered in background/kill states?
What works currently:
TTS and vibration only work in foreground when the app is active.
Critical alert sound works correctly in all states.
I want confirmation on whether iOS supports background/terminated TTS and vibration, or if this is a platform restriction even when using Critical Alerts.
Thank you!
Hello,
I am wondering if it is possible to have audio from my AirPods be sent to my speech to text service and at the same time have the built in mic audio input be sent to recording a video?
I ask because I want my users to be able to say "CAPTURE" and I start recording a video (with audio from the built in mic) and then when the user says "STOP" I stop the recording.
So experimenting with the new SpeechTranscriber, if I do:
let transcriber = SpeechTranscriber(
locale: locale,
transcriptionOptions: [],
reportingOptions: [.volatileResults],
attributeOptions: [.audioTimeRange]
)
only the final result has audio time ranges, not the volatile results.
Is this a performance consideration? If there is no performance problem, it would be nice to have the option to also get speech time ranges for volatile responses.
I'm not presenting the volatile text at all in the UI, I was just trying to keep statistics about the non-speech and the speech noise level, this way I can determine when the noise level falls under the noisefloor for a while.
The goal here was to finalize the recording automatically, when the noise level indicate that the user has finished speaking.
I've tried SpeechTranscriber with a lot of my devices (from iPhone 12 series ~ iPhone 17 series) without issues. However, SpeechTranscriber.isAvailable value is false for my iPhone 11 Pro.
https://developer.apple.com/documentation/speech/speechtranscriber/isavailable
I'am curious why the iPhone 11 Pro device is not supported. Are all iPhone 11 series not supported intentionally? Or is there any problem with my specific device?
I've also checked the supportedLocales, and the value is an empty array.
https://developer.apple.com/documentation/speech/speechtranscriber/supportedlocales
I have the new iOS 26 SpeechTranscriber working in my application. The issue I am facing is how to determine if the device I am running on supports SpeechTranscriber. I was able to create code that tests if the device supports transcription but it takes a bit of time to run and thus the results are not available when the app launches. What I am looking for is a list of what iOS 26 devices it doesn't run on. I think its safe to assume any new devices will support it so if we can just have a list of what devices that can run iOS 26 and not able to do transcription it would be much faster for the app. I have determined it doesn't work on a SE 2nd Gen, it works on iPhone 12, SE 3rd Gen, iPhone 14 Pro, 15 Pro. As the SpeechTranscriber doesn't work in the simulator I can't determine that way. I have checked the docs and it doesn't list the devices it doesn't work on.
I am using the sample app from:
https://developer.apple.com/videos/play/wwdc2025/277/?time=763
I installed this on an Iphone 15 Pro with iOS 26 beta 1. I was able to get good transcription with it. The app did crash sometimes when transcribing and I was going to post here with the details. I then installed iOS beta 2 and uninstalled the sample app. Now every time I try to run the sample app on the 15 Pro I get this message:
SpeechAnalyzer: Input loop ending with error: Error Domain=SFSpeechErrorDomain Code=10 "Cannot use modules with unallocated locales [en_US (fixed en_US)]" UserInfo={NSLocalizedDescription=Cannot use modules with unallocated locales [en_US (fixed en_US)]}
I can't continue our our work towards using SpeechAnalyzer now with this error.
I have set breakpoints on all the catch handlers and it doesn't catch this error. My phone region is "United States"
For what iPhone and iPad models under iOS 26 SpeechTranscriber.isAvailable is true
Hello,
I am a developer planning to build an application using Apple's new SpeechTranscriber technology.
I am facing an issue where SpeechTranscriber is not available on my iPad Pro (11-inch, 2nd generation, model number: MXDC2J/A), even though I have updated it to iPadOS 26. I was under the impression that SpeechTranscriber would be available on any device running iPadOS 26. Could you please clarify if this is incorrect?
Furthermore, I am planning to purchase a new iPad with an A16 chip for the development and deployment of this application. Can you confirm if SpeechTranscriber will be fully functional on an iPad equipped with the A16 chip?
Thank you for your assistance.
I am trying to use SpeechTranscriber from Speech framework. Is it possible to use it on Simulator of iOS 26 (Mac OS Tahoe)? Function "supportedLocales" returns an empty array.
It looks like Apple has added some new API(s) to SFSpeechRecognition
My app, which is currently listed on App Store does feature speech recognition.
Yet, trying to use it under iOS 18.0 throws errors:
-[SFSpeechRecognitionTask localSpeechRecognitionClient:speechRecordingDidFail:]_block_invoke Ignoring subsequent local speech recording error: Error Domain=kAFAssistantErrorDomain Code=1101 "(null)"
What happens is that after several words are transcribed and displayed, the next sentence results in previous words disappearance.
That's probably what that portion of the error text - "Ignoring subsequent local speech recording error: Error Domain=kAFAssistantErrorDomain Code=1101 "(null)" means.
The problem occurs ONLY when the app is running under iOS 18.0
Even when it's compiled in Xcode 16.0 using iOS 17.5 everything works fine.
Any suggestions?
Hi everyone 👋
I’m building an iOS app in Swift where I want to do the following:
Record the user’s voice
Transcribe the spoken sentence (speech-to-text)
Auto-detect the spoken language
Translate it to another language selected by the user (e.g., English → Spanish or Hindi → English)
Speak back (text-to-speech) the translated text on the same device
Is this possible to record via phone mic and play the transcribe voice into headphone's audio?
I am developing an app with transcription and I am exploring ways to improve the transcription from the SpeechAnalyzer/Transcriber for technical terms. SFSpeech... recognition had the capability of being augmented by contextualStrings. Does something similar exist for SpeechAnalyzer/Transcriber? If so please point me towards the documentation and any sample code that may exist for this. If there are other options, please let me know.