Carescribe fork notes

This is a fork of the original project because

At time of publishing, the develop branch of this library do not support use cases in CLI applications. A PR was merged that fixed this this but various code changes from 9th April on the develop branch broke other parts of the library. The main branch in this fork removes those changes and keeps only the fixes to PR 51.[]

🔊 SimplyCoreAudio

SimplyCoreAudio (formerly known as AMCoreAudio) is a Swift framework that aims to make Core Audio use less tedious in macOS.

Features

• Enumerating audio devices (see SimplyCoreAudio)
• Getting/setting default input, output and system device (see SimplyCoreAudio)
• Creating and destroying aggregate devices (see SimplyCoreAudio)
• Querying audio device properties such as: name, manufacturer, UID, volume, mute, sample rate, clock source, etc. (see AudioDevice)
• Managing (physical and virtual) audio streams associated to an audio device (see AudioStream)
• Subscribing to audio hardware, audio device, and audio stream notifications (see Notification Extensions)

Resources

• API Reference
• Core Audio
• HALLab (distributed as part of the Additional Tools for Xcode package)

Requirements

• Xcode 12+
• Swift 4.0+
• macOS 10.12+

Installation

To install the Swift Package, please follow the steps below:

• Add https://github.com/rnine/SimplyCoreAudio.git as a Swift Package Manager dependency to your project.
• When asked to Choose Package Options, use the default settings provided by Xcode.
• When asked to Add Package, add SimplyCoreAudio to your desired target(s).

Usage

1. Import SimplyCoreAudio

   import SimplyCoreAudio

2. Instantiate SimplyCoreAudio

   let simplyCA = SimplyCoreAudio()

3. Interact with SimplyCoreAudio

   // Get the default output device
   let device = simplyCA.defaultOutputDevice
   
   // Get preferred output channels
   if let stereoPair = device.preferredChannelsForStereo(scope: .output) {
       let leftChannel = stereoPair.left
       let rightChannel = stereoPair.right
       // Use channels...
   }
   
   // Get device samplerate
   if let sampleRate = device.nominalSampleRate {
       // Use samplerate...
   }
   
   // Get device virtual master volume
   if let outVolume = device.virtualMasterVolume(scope: .output) {
       // Use output volume...
   }

4. Subscribe to hardware-related notifications

   // e.g., subscribing to `deviceListChanged` notification.
   var observer = NotificationCenter.default.addObserver(forName: .deviceListChanged,
                                                          object: nil,
                                                           queue: .main) { (notification) in
       // Get added devices.
       guard let addedDevices = notification.userInfo?["addedDevices"] as? [AudioDevice] else { return }
   
       // Get removed devices.
       guard let removedDevices = notification.userInfo?["removedDevices"] as? [AudioDevice] else { return }
   }
   
   // Once done observing, remove observer and nil it.
   NotificationCenter.default.removeObserver(observer)
   observer = nil

5. Subscribe to notifications from a specific audio device

   // Get the default output device
   let device = simplyCA.defaultOutputDevice
   
   // e.g., subscribing to `deviceNominalSampleRateDidChange` notification.
   var observer = NotificationCenter.default.addObserver(forName: .deviceNominalSampleRateDidChange,
                                                          object: device,
                                                           queue: .main) { (notification) in
       // Handle notification.
   }
   
   // Once done observing, remove observer and nil it.
   NotificationCenter.default.removeObserver(observer)
   observer = nil

6. Subscribe to notifications from a specific audio stream

   // Get the default output device
   let device = simplyCA.defaultOutputDevice
   
   // Get the first output stream
   guard let streams = device.streams(scope: .output) else { return }
   guard let stream0 = streams.first else { return }
   
   // e.g., subscribing to `streamPhysicalFormatDidChange` notification.
   var observer = NotificationCenter.default.addObserver(forName: .streamPhysicalFormatDidChange,
                                                          object: stream0,
                                                           queue: .main) { (notification) in
       // Handle notification.
   }
   
   // Once done observing, remove observer and nil it.
   NotificationCenter.default.removeObserver(observer)
   observer = nil

Supported Notifications

Audio Hardware Notifications

Name	Purpose	User Info
defaultInputDeviceChanged	Called whenever the default input device changes.	N/A
defaultOutputDeviceChanged	Called whenever the default output device changes.	N/A
defaultSystemOutputDeviceChanged	Called whenever the default system output device changes.	N/A
deviceListChanged	Called whenever the list of hardware devices and device subdevices changes.	addedDevices: [AudioDevice], removedDevices: [AudioDevice]

Audio Device Notifications

Name	Purpose	User Info
deviceNominalSampleRateDidChange	Called whenever the audio device's sample rate changes.	N/A
deviceAvailableNominalSampleRatesDidChange	Called whenever the audio device's list of nominal sample rates changes.	N/A
deviceClockSourceDidChange	Called whenever the audio device's clock source changes.	N/A
deviceNameDidChange	Called whenever the audio device's name changes.
deviceOwnedObjectsDidChange	Called whenever the list of owned audio devices on this audio device changes.	N/A
deviceVolumeDidChange	Called whenever the audio device's volume for a given channel and scope changes.	channel: UInt32, scope: Scope
deviceMuteDidChange	Called whenever the audio device's mute state for a given channel and scope changes.	channel: UInt32, scope: Scope
deviceIsAliveDidChange	Called whenever the audio device's list of nominal sample rates changes.	N/A
deviceIsRunningDidChange	Called whenever the audio device's is running property changes.	N/A
deviceIsRunningSomewhereDidChange	Called whenever the audio device's is running somewhere property changes.	N/A
deviceIsJackConnectedDidChange	Called whenever the audio device's is jack connected property changes.	N/A
devicePreferredChannelsForStereoDidChange	Called whenever the audio device's preferred channels for stereo property changes.	N/A
deviceHogModeDidChange	Called whenever the audio device's hog mode property changes.	N/A

Audio Stream Notifications

Name	Purpose	User Info
streamIsActiveDidChange	Called whenever the audio stream isActive flag changes state.	N/A
streamPhysicalFormatDidChange	Called whenever the audio stream physical format changes.	N/A

Further Development & Patches

Do you want to contribute to the project? Please fork, patch, and then submit a pull request!

Running Tests

Please make sure to install NullAudio.driver before attempting to run tests:

Installing NullAudio.driver

1. Unzip NullAudio.driver.zip and install driver into the system HAL Plug-Ins folder

   sudo unzip Tests/Extras/NullAudio.driver.zip -d /Library/Audio/Plug-Ins/HAL

2. Reload coreaudiod

   sudo launchctl kill KILL system/com.apple.audio.coreaudiod

Demo Project

• SimplyCoreAudioDemo — a basic SwiftUI-based demo showcasing device enumeration and notifications.

License

SimplyCoreAudio was written by Ruben Nine (@rnine) in 2013-2014 (open-sourced in March 2014) and is licensed under the MIT license. See LICENSE.md.