Stereo recording feature for Example iOS ver 2025

[shogo4405]

Description & motivation

• The stereo streaming example was not working, so I rewrote it as the 2025 edition.
• The key points to make it work are as follows:

1. Configure AVAudioSession as shown below.
   

   HaishinKit.swift/Examples/iOS/AudioSourceService.swift

   Lines 57 to 61 in 5a48dbd

   	// If you set the "mode" parameter, stereo capture is not possible, so it is left unspecified.
   	try session.setCategory(.playAndRecord, mode: .videoRecording, options: [.defaultToSpeaker, .allowBluetooth])
   	// It looks like this setting is required on iOS 18.5.
   	try session.setPreferredInputNumberOfChannels(2)
   	try session.setActive(true)

2. Set the following values in MediaMixer.
   

   HaishinKit.swift/Examples/iOS/IngestViewModel.swift

   Lines 113 to 116 in 5a48dbd

   	await mixer.configuration { session in
   	// It is required for the stereo setting.
   	session.automaticallyConfiguresApplicationAudioSession = false
   	}

3. Refer to the code in the PR below for the stereo source.
   

   HaishinKit.swift/Examples/iOS/AudioSourceService.swift

   Lines 74 to 93 in 5a48dbd

   	func selectAudioSource(_ audioSource: AudioSource) throws {
   	setPreferredInputBuiltInMic(true)
   	guard let preferredInput = AVAudioSession.sharedInstance().preferredInput,
   	let dataSources = preferredInput.dataSources,
   	let newDataSource = dataSources.first(where: { $0.dataSourceName == audioSource.dataSourceName }),
   	let supportedPolarPatterns = newDataSource.supportedPolarPatterns else {
   	throw Error.missingDataSource(audioSource)
   	}
   	do {
   	let isStereoSupported = supportedPolarPatterns.contains(.stereo)
   	if isStereoSupported {
   	try newDataSource.setPreferredPolarPattern(.stereo)
   	}
   	try preferredInput.setPreferredDataSource(newDataSource)
   	} catch {
   	logger.warn(error)
   	}
   	}
   	private func makeAudioSources() -> [AudioSource] {

Type of change

• New feature (non-breaking change which adds functionality)

Screenshots: