[iOS] AVFoundationを使用して、「ビデオ録画」や「連写カメラ」や「QRコードリーダー」や「バーコードリーダー」を作ってみた　

for device in AVCaptureDevice.devices() as! [AVCaptureDevice]{
    print("localizedName=\(device.localizedName!) modelID=\(device.modelID!)")
}

localizedName=Back Camera modelID=com.apple.avfoundation.avcapturedevice.built-in_video:0
localizedName=Front Camera modelID=com.apple.avfoundation.avcapturedevice.built-in_video:1
localizedName=iPhone マイク modelID=com.apple.avfoundation.avcapturedevice.built-in_audio:0

let videoDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
let audioDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeAudio)

var videoDevice: AVCaptureDevice
for device in AVCaptureDevice.devices() {
    if (device as AnyObject).position == AVCaptureDevicePosition.front {
        videoDevice = device as! AVCaptureDevice
    }
}

// 露出モード
var exposureMode: AVCaptureExposureMode { get set }

// フォーカスモード
var focusMode: AVCaptureFocusMode { get set }

// フラッシュ
var flashMode: AVCaptureFlashMode { get set }

// フォーカス位置
var focusPointOfInterest: CGPoint { get set }

// ホワイトバランスモード
var whiteBalanceMode: AVCaptureWhiteBalanceMode { get set }

let cameraDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
do {
    try cameraDevice.lockForConfiguration() // ロック開始
    if cameraDevice.isFlashModeSupported(AVCaptureFlashMode.on) { // プロパティの有効性を確認
        cameraDevice.flashMode = AVCaptureFlashMode.on // プロパティの設定
    }
} catch {
    // error
}
cameraDevice.unlockForConfiguration() // ロック解除

// セッションのインスタンス化
let captureSession = AVCaptureSession()

// デバイスの初期化
let videoDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo) // カメラ
let audioDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeAudio) // マイク

// デバイスの接続
let videoInput = try! AVCaptureDeviceInput.init(device: videoDevice)
captureSession.addInput(videoInput)
let audioInput = try! AVCaptureDeviceInput.init(device: audioDevice)
captureSession.addInput(audioInput);

// 出力の初期化
let fileOutput = AVCaptureMovieFileOutput() // 映像ファイル

// 出力の接続
captureSession.addOutput(fileOutput)

for device in captureSession.inputs {
    print(device)
}
// <AVCaptureDeviceInput: 0x136d3bd50 [Back Camera]>
// <AVCaptureDeviceInput: 0x136d4bb40 [iPhone マイク]>

for output in captureSession.outputs {
    print(output)
}
// <AVCaptureMovieFileOutput: 0x136d32ee0>

for connection in fileOutput.connections as! [AVCaptureConnection] {
    print(connection)
    for port in connection.inputPorts as! [AVCaptureInputPort] {
        if port.mediaType == AVMediaTypeVideo {
            print("Video")
        }
    }
}
// <AVCaptureConnection: 0x127d3bc40 [type:vide][enabled:1][active:1]>
// Video
// <AVCaptureConnection: 0x127d3dd90 [type:soun][enabled:1][active:1]>

DispatchQueue.global(qos: .userInitiated).async {
    self.captureSession.startRunning()
}

captureSession.beginConfiguration()
if captureSession.canSetSessionPreset(AVCaptureSessionPresetHigh) {
    captureSession.sessionPreset = AVCaptureSessionPresetHigh
}
captureSession.commitConfiguration()

static let AVCaptureSessionDidStartRunning: NSNotification.Name
static let AVCaptureSessionDidStopRunning: NSNotification.Name
static let AVCaptureSessionWasInterrupted: NSNotification.Name
static let AVCaptureSessionInterruptionEnded: NSNotification.Name

if let videoLayer = AVCaptureVideoPreviewLayer.init(session: captureSession) {
    videoLayer.frame = monitorView.bounds
    videoLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
    monitorView.layer.addSublayer(videoLayer)
}

privacy-sensitive data without a usage description.  The app's Info.plist must contain an NSCameraUsageDescription key with a string value explaining to the user how the app uses this data.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>NSCameraUsageDescription</key>
    <string>ビデオ撮影のためにカメラを使用します。</string>
    <key>NSMicrophoneUsageDescription</key>
    <string>ビデオ撮影のためにマイクを使用します。</string>

・・・省略・・・