Meeting detection

MeetingDetector watches which call apps are using the microphone. That is the most reliable sign that a call is running: it works for native apps and for calls in a browser, and it needs no permission, since it reads Core Audio's per-process "running input" flag and never touches audio.

let detector = MeetingDetector()
detector.onChange = { started, ended in
    for meeting in started { print("\(meeting.appName) call started") }
    for meeting in ended { print("\(meeting.appName) call ended") }
}
detector.start()

start and stop run on the main actor, and onChange is called on the main queue.

TimingCopy Anchor Link

Polling is used on purpose: Core Audio's process-list notifications do not fire when an existing process starts using the microphone.

detector.active lists the calls in progress, and currentMeetings() returns the apps using the microphone right now, without any delay.

Which appsCopy Anchor Link

MeetingDetector.knownApps maps bundle IDs to names:

Zoom, Microsoft Teams (both versions), Slack, Discord, FaceTime, WhatsApp, Webex, Signal, Telegram, and the browsers Chrome, Brave, Edge, Arc, Safari, Firefox, Vivaldi and Opera.

A browser only counts while it uses the microphone, which covers Google Meet, Teams on the web and similar. Pass your own list to watch other apps:

var apps = MeetingDetector.knownApps
apps["com.example.CallApp"] = "Example"
let detector = MeetingDetector(watchedApps: apps, startDelay: 2, endDelay: 10)

Recording only the callCopy Anchor Link

DetectedMeeting.bundleID plugs straight into a source:

detector.onChange = { started, _ in
    guard let meeting = started.first else { return }
    Task {
        try await recorder.start(.init(systemAudio: .apps([meeting.bundleID])), in: folder)
    }
}

For browsers, .everything is often the better choice: the call may play from a different tab or helper than the one holding the microphone.