Migrate DefaultCamera initialization to Swift

Author: RobertOdrowaz

packages/camera/camera_avfoundation/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.9.21+2
+
+* Migrates `DefaultCamera` initialization to Swift.
+* Removes unused `textureId` field of `FLTCam` class.
+
 ## 0.9.21+1
 
 * Migrates `startImageStream` and `setUpCaptureSessionForAudioIfNeeded` methods to Swift.

packages/camera/camera_avfoundation/example/ios/RunnerTests/CameraTestUtils.swift

@@ -82,7 +82,7 @@ enum CameraTestUtils {
   }
 
   static func createTestCamera(_ configuration: FLTCamConfiguration) -> DefaultCamera {
-    return DefaultCamera(configuration: configuration, error: nil)
+    return (try? DefaultCamera(configuration: configuration))!
   }
 
   static func createTestCamera() -> DefaultCamera {

packages/camera/camera_avfoundation/example/ios/RunnerTests/PhotoCaptureTests.swift

@@ -32,8 +32,7 @@ final class PhotoCaptureTests: XCTestCase {
     let mockOutput = MockCapturePhotoOutput()
     mockOutput.capturePhotoWithSettingsStub = { settings, photoDelegate in
       let delegate =
-        cam.inProgressSavePhotoDelegates.object(forKey: settings.uniqueID)
-        as? FLTSavePhotoDelegate
+        cam.inProgressSavePhotoDelegates[settings.uniqueID]
       // Completion runs on IO queue.
       let ioQueue = DispatchQueue(label: "io_queue")
       ioQueue.async {
@@ -66,8 +65,7 @@ final class PhotoCaptureTests: XCTestCase {
     let mockOutput = MockCapturePhotoOutput()
     mockOutput.capturePhotoWithSettingsStub = { settings, photoDelegate in
       let delegate =
-        cam.inProgressSavePhotoDelegates.object(forKey: settings.uniqueID)
-        as? FLTSavePhotoDelegate
+        cam.inProgressSavePhotoDelegates[settings.uniqueID]
       // Completion runs on IO queue.
       let ioQueue = DispatchQueue(label: "io_queue")
       ioQueue.async {
@@ -101,8 +99,7 @@ final class PhotoCaptureTests: XCTestCase {
     mockOutput.availablePhotoCodecTypes = [AVVideoCodecType.hevc]
     mockOutput.capturePhotoWithSettingsStub = { settings, photoDelegate in
       let delegate =
-        cam.inProgressSavePhotoDelegates.object(forKey: settings.uniqueID)
-        as? FLTSavePhotoDelegate
+        cam.inProgressSavePhotoDelegates[settings.uniqueID]
       // Completion runs on IO queue.
       let ioQueue = DispatchQueue(label: "io_queue")
       ioQueue.async {
@@ -136,8 +133,7 @@ final class PhotoCaptureTests: XCTestCase {
     let mockOutput = MockCapturePhotoOutput()
     mockOutput.capturePhotoWithSettingsStub = { settings, photoDelegate in
       let delegate =
-        cam.inProgressSavePhotoDelegates.object(forKey: settings.uniqueID)
-        as? FLTSavePhotoDelegate
+        cam.inProgressSavePhotoDelegates[settings.uniqueID]
       // Completion runs on IO queue.
       let ioQueue = DispatchQueue(label: "io_queue")
       ioQueue.async {
@@ -185,8 +181,7 @@ final class PhotoCaptureTests: XCTestCase {
     let mockOutput = MockCapturePhotoOutput()
     mockOutput.capturePhotoWithSettingsStub = { settings, photoDelegate in
       let delegate =
-        cam.inProgressSavePhotoDelegates.object(forKey: settings.uniqueID)
-        as? FLTSavePhotoDelegate
+        cam.inProgressSavePhotoDelegates[settings.uniqueID]
       // Completion runs on IO queue.
       let ioQueue = DispatchQueue(label: "io_queue")
       ioQueue.async {

packages/camera/camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/CameraPlugin.swift

@@ -248,19 +248,18 @@ extension CameraPlugin: FCPCameraApi {
       initialCameraName: name
     )
 
-    var error: NSError?
-    let newCamera = DefaultCamera(configuration: camConfiguration, error: &error)
+    do {
+      let newCamera = try DefaultCamera(configuration: camConfiguration)
 
-    if let error = error {
-      completion(nil, CameraPlugin.flutterErrorFromNSError(error))
-    } else {
       camera?.close()
       camera = newCamera
 
       FLTEnsureToRunOnMainQueue { [weak self] in
         guard let strongSelf = self else { return }
         completion(NSNumber(value: strongSelf.registry.register(newCamera)), nil)
       }
+    } catch let error as NSError {
+      completion(nil, CameraPlugin.flutterErrorFromNSError(error))
     }
   }
 

packages/camera/camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift

@@ -13,7 +13,7 @@ final class DefaultCamera: FLTCam, Camera {
   var dartAPI: FCPCameraEventApi?
   var onFrameAvailable: (() -> Void)?
 
-  override var videoFormat: FourCharCode {
+  var videoFormat: FourCharCode = kCVPixelFormatType_32BGRA {
     didSet {
       captureVideoOutput.videoSettings = [
         kCVPixelBufferPixelFormatTypeKey as String: videoFormat
@@ -47,11 +47,33 @@ final class DefaultCamera: FLTCam, Camera {
   /// Videos are written to disk by `videoAdaptor` on an internal queue managed by AVFoundation.
   private let photoIOQueue = DispatchQueue(label: "io.flutter.camera.photoIOQueue")
 
+  /// All DefaultCamera's state access and capture session related operations should be run on this queue.
+  private let captureSessionQueue: DispatchQueue
+
+  private let mediaSettings: FCPPlatformMediaSettings
+  private let mediaSettingsAVWrapper: FLTCamMediaSettingsAVWrapper
+
+  /// A wrapper for AVCaptureDevice creation to allow for dependency injection in tests.
+  private let captureDeviceFactory: CaptureDeviceFactory
+  private let audioCaptureDeviceFactory: AudioCaptureDeviceFactory
+  private let captureDeviceInputFactory: FLTCaptureDeviceInputFactory
+  private let assetWriterFactory: AssetWriterFactory
+  private let inputPixelBufferAdaptorFactory: InputPixelBufferAdaptorFactory
+
+  private let deviceOrientationProvider: FLTDeviceOrientationProviding
+
   private var videoWriter: FLTAssetWriter?
   private var videoWriterInput: FLTAssetWriterInput?
   private var audioWriterInput: FLTAssetWriterInput?
   private var videoAdaptor: FLTAssetWriterInputPixelBufferAdaptor?
 
+  /// A dictionary to retain all in-progress FLTSavePhotoDelegates. The key of the dictionary is the
+  /// AVCapturePhotoSettings's uniqueID for each photo capture operation, and the value is the
+  /// FLTSavePhotoDelegate that handles the result of each photo capture operation. Note that photo
+  /// capture operations may overlap, so FLTCam has to keep track of multiple delegates in progress,
+  /// instead of just a single delegate reference.
+  private(set) var inProgressSavePhotoDelegates = [Int64: FLTSavePhotoDelegate]()
+
   private var imageStreamHandler: FLTImageStreamHandler?
 
   /// Tracks the latest pixel buffer sent from AVFoundation's sample buffer delegate callback.
@@ -69,6 +91,9 @@ final class DefaultCamera: FLTCam, Camera {
   private var videoTimeOffset = CMTime.zero
   private var audioTimeOffset = CMTime.zero
 
+  /// True when images from the camera are being streamed.
+  private(set) var isStreamingImages = false
+
   /// Number of frames currently pending processing.
   private var streamingPendingFramesCount = 0
 
@@ -80,6 +105,7 @@ final class DefaultCamera: FLTCam, Camera {
 
   private var exposureMode = FCPPlatformExposureMode.auto
   private var focusMode = FCPPlatformFocusMode.auto
+  private var flashMode: FCPPlatformFlashMode
 
   private static func flutterErrorFromNSError(_ error: NSError) -> FlutterError {
     return FlutterError(
@@ -116,6 +142,95 @@ final class DefaultCamera: FLTCam, Camera {
     return (captureVideoInput, captureVideoOutput, connection)
   }
 
+  init(configuration: FLTCamConfiguration) throws {
+    captureSessionQueue = configuration.captureSessionQueue
+    mediaSettings = configuration.mediaSettings
+    mediaSettingsAVWrapper = configuration.mediaSettingsWrapper
+    captureDeviceFactory = configuration.captureDeviceFactory
+    audioCaptureDeviceFactory = configuration.audioCaptureDeviceFactory
+    captureDeviceInputFactory = configuration.captureDeviceInputFactory
+    assetWriterFactory = configuration.assetWriterFactory
+    inputPixelBufferAdaptorFactory = configuration.inputPixelBufferAdaptorFactory
+    deviceOrientationProvider = configuration.deviceOrientationProvider
+
+    let captureDevice = captureDeviceFactory(configuration.initialCameraName)
+    flashMode = captureDevice.hasFlash ? .auto : .off
+
+    super.init()
+
+    videoCaptureSession = configuration.videoCaptureSession
+    audioCaptureSession = configuration.audioCaptureSession
+    videoDimensionsForFormat = configuration.videoDimensionsForFormat
+
+    self.captureDevice = captureDevice
+
+    capturePhotoOutput = FLTDefaultCapturePhotoOutput(photoOutput: AVCapturePhotoOutput())
+    capturePhotoOutput.highResolutionCaptureEnabled = true
+
+    videoCaptureSession.automaticallyConfiguresApplicationAudioSession = false
+    audioCaptureSession.automaticallyConfiguresApplicationAudioSession = false
+
+    deviceOrientation = configuration.orientation
+
+    let connection: AVCaptureConnection
+    (captureVideoInput, captureVideoOutput, connection) = try DefaultCamera.createConnection(
+      captureDevice: captureDevice,
+      videoFormat: videoFormat,
+      captureDeviceInputFactory: configuration.captureDeviceInputFactory)
+
+    captureVideoOutput.setSampleBufferDelegate(self, queue: captureSessionQueue)
+
+    videoCaptureSession.addInputWithNoConnections(captureVideoInput)
+    videoCaptureSession.addOutputWithNoConnections(captureVideoOutput.avOutput)
+    videoCaptureSession.addConnection(connection)
+
+    videoCaptureSession.addOutput(capturePhotoOutput.avOutput)
+
+    motionManager.startAccelerometerUpdates()
+
+    if mediaSettings.framesPerSecond != nil {
+      // The frame rate can be changed only on a locked for configuration device.
+      try mediaSettingsAVWrapper.lockDevice(captureDevice)
+      mediaSettingsAVWrapper.beginConfiguration(for: videoCaptureSession)
+
+      // Possible values for presets are hard-coded in FLT interface having
+      // corresponding AVCaptureSessionPreset counterparts.
+      // If _resolutionPreset is not supported by camera there is
+      // fallback to lower resolution presets.
+      // If none can be selected there is error condition.
+      do {
+        try setCaptureSessionPreset(mediaSettings.resolutionPreset)
+      } catch {
+        videoCaptureSession.commitConfiguration()
+        captureDevice.unlockForConfiguration()
+        throw error
+      }
+
+      FLTSelectBestFormatForRequestedFrameRate(
+        captureDevice,
+        mediaSettings,
+        videoDimensionsForFormat)
+
+      if let framesPerSecond = mediaSettings.framesPerSecond {
+        // Set frame rate with 1/10 precision allowing non-integral values.
+        let fpsNominator = floor(framesPerSecond.doubleValue * 10.0)
+        let duration = CMTimeMake(value: 10, timescale: Int32(fpsNominator))
+
+        mediaSettingsAVWrapper.setMinFrameDuration(duration, on: captureDevice)
+        mediaSettingsAVWrapper.setMaxFrameDuration(duration, on: captureDevice)
+      }
+
+      mediaSettingsAVWrapper.commitConfiguration(for: videoCaptureSession)
+      mediaSettingsAVWrapper.unlockDevice(captureDevice)
+    } else {
+      // If the frame rate is not important fall to a less restrictive
+      // behavior (no configuration locking).
+      try setCaptureSessionPreset(mediaSettings.resolutionPreset)
+    }
+
+    updateOrientation()
+  }
+
   func setUpCaptureSessionForAudioIfNeeded() {
     // Don't setup audio twice or we will lose the audio.
     guard !mediaSettings.enableAudio || !isAudioSetup else { return }
@@ -467,8 +582,9 @@ final class DefaultCamera: FLTCam, Camera {
         guard let strongSelf = self else { return }
 
         strongSelf.captureSessionQueue.async { [weak self] in
-          self?.inProgressSavePhotoDelegates.removeObject(
-            forKey: settings.uniqueID)
+          self?.inProgressSavePhotoDelegates.removeValue(
+            forKey:
+              settings.uniqueID)
         }
 
         if let error = error {