[camera] Implement interface methods to allow concurrent stream and record

packages/camera/camera/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.10.1
+
+* Implements option to also stream when recording a video.
+
 ## 0.10.0+4
 
 * Removes usage of `_ambiguate` method in example.

packages/camera/camera/lib/src/camera_controller.dart

@@ -459,12 +459,6 @@ class CameraController extends ValueNotifier<CameraValue> {
     assert(defaultTargetPlatform == TargetPlatform.android ||
         defaultTargetPlatform == TargetPlatform.iOS);
     _throwIfNotInitialized('stopImageStream');
-    if (value.isRecordingVideo) {
-      throw CameraException(
-        'A video recording is already started.',
-        'stopImageStream was called while a video is being recorded.',
-      );
-    }
     if (!value.isStreamingImages) {
       throw CameraException(
         'No camera is streaming images',
@@ -483,28 +477,35 @@ class CameraController extends ValueNotifier<CameraValue> {
 
   /// Start a video recording.
   ///
+  /// You may optionally pass an [onAvailable] callback to also have the
+  /// video frames streamed to this callback.
+  ///
   /// The video is returned as a [XFile] after calling [stopVideoRecording].
   /// Throws a [CameraException] if the capture fails.
-  Future<void> startVideoRecording() async {
+  Future<void> startVideoRecording(
+      {onLatestImageAvailable? onAvailable}) async {
     _throwIfNotInitialized('startVideoRecording');
     if (value.isRecordingVideo) {
       throw CameraException(
         'A video recording is already started.',
         'startVideoRecording was called when a recording is already started.',
       );
     }
-    if (value.isStreamingImages) {
-      throw CameraException(
-        'A camera has started streaming images.',
-        'startVideoRecording was called while a camera was streaming images.',
-      );
+
+    Function(CameraImageData image)? streamCallback;
+    if (onAvailable != null) {
+      streamCallback = (CameraImageData imageData) {
+        onAvailable(CameraImage.fromPlatformInterface(imageData));
+      };
     }
 
     try {
-      await CameraPlatform.instance.startVideoRecording(_cameraId);
+      await CameraPlatform.instance.startVideoCapturing(
+          VideoCaptureOptions(_cameraId, streamCallback: streamCallback));
       value = value.copyWith(
           isRecordingVideo: true,
           isRecordingPaused: false,
+          isStreamingImages: onAvailable != null,
           recordingOrientation: Optional<DeviceOrientation>.of(
               value.lockedCaptureOrientation ?? value.deviceOrientation));
     } on PlatformException catch (e) {
@@ -523,6 +524,11 @@ class CameraController extends ValueNotifier<CameraValue> {
         'stopVideoRecording was called when no video is recording.',
       );
     }
+
+    if (value.isStreamingImages) {
+      stopImageStream();
+    }
+
     try {
       final XFile file =
           await CameraPlatform.instance.stopVideoRecording(_cameraId);

packages/camera/camera/pubspec.yaml

@@ -4,7 +4,7 @@ description: A Flutter plugin for controlling the camera. Supports previewing
   Dart.
 repository: https://github.com/flutter/plugins/tree/main/packages/camera/camera
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
-version: 0.10.0+4
+version: 0.10.1
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
@@ -21,10 +21,10 @@ flutter:
         default_package: camera_web
 
 dependencies:
-  camera_android: ^0.10.0
-  camera_avfoundation: ^0.9.7+1
-  camera_platform_interface: ^2.2.0
-  camera_web: ^0.3.0
+  camera_android: ^0.10.1
+  camera_avfoundation: ^0.10.0
+  camera_platform_interface: ^2.3.1
+  camera_web: ^0.3.1
   flutter:
     sdk: flutter
   flutter_plugin_android_lifecycle: ^2.0.2

packages/camera/camera/test/camera_image_stream_test.dart

@@ -130,7 +130,7 @@ void main() {
     );
   });
 
-  test('stopImageStream() throws $CameraException when recording videos',
+  test('stopImageStream() throws $CameraException when not streaming images',
       () async {
     final CameraController cameraController = CameraController(
         const CameraDescription(
@@ -140,50 +140,61 @@ void main() {
         ResolutionPreset.max);
     await cameraController.initialize();
 
-    await cameraController.startImageStream((CameraImage image) => null);
-    cameraController.value =
-        cameraController.value.copyWith(isRecordingVideo: true);
     expect(
         cameraController.stopImageStream,
         throwsA(isA<CameraException>().having(
           (CameraException error) => error.description,
-          'A video recording is already started.',
-          'stopImageStream was called while a video is being recorded.',
+          'No camera is streaming images',
+          'stopImageStream was called when no camera is streaming images.',
         )));
   });
 
-  test('stopImageStream() throws $CameraException when not streaming images',
-      () async {
+  test('stopImageStream() intended behaviour', () async {
     final CameraController cameraController = CameraController(
         const CameraDescription(
             name: 'cam',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 90),
         ResolutionPreset.max);
     await cameraController.initialize();
+    await cameraController.startImageStream((CameraImage image) => null);
+    await cameraController.stopImageStream();
 
-    expect(
-        cameraController.stopImageStream,
-        throwsA(isA<CameraException>().having(
-          (CameraException error) => error.description,
-          'No camera is streaming images',
-          'stopImageStream was called when no camera is streaming images.',
-        )));
+    expect(mockPlatform.streamCallLog,
+        <String>['onStreamedFrameAvailable', 'listen', 'cancel']);
   });
 
-  test('stopImageStream() intended behaviour', () async {
+  test('startVideoRecording() can stream images', () async {
+    final CameraController cameraController = CameraController(
+        const CameraDescription(
+            name: 'cam',
+            lensDirection: CameraLensDirection.back,
+            sensorOrientation: 90),
+        ResolutionPreset.max);
+
+    await cameraController.initialize();
+
+    cameraController.startVideoRecording(
+        onAvailable: (CameraImage image) => null);
+
+    expect(mockPlatform.streamCallLog,
+        <String>['startVideoRecording with stream']);
+  });
+
+  test('startVideoRecording() by default does not stream', () async {
     final CameraController cameraController = CameraController(
         const CameraDescription(
             name: 'cam',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 90),
         ResolutionPreset.max);
+
     await cameraController.initialize();
-    await cameraController.startImageStream((CameraImage image) => null);
-    await cameraController.stopImageStream();
+
+    cameraController.startVideoRecording();
 
     expect(mockPlatform.streamCallLog,
-        <String>['onStreamedFrameAvailable', 'listen', 'cancel']);
+        <String>['startVideoRecording without stream']);
   });
 }
 
@@ -203,6 +214,20 @@ class MockStreamingCameraPlatform extends MockCameraPlatform {
     return _streamController!.stream;
   }
 
+  @override
+  Future<XFile> startVideoRecording(int cameraId,
+      {Duration? maxVideoDuration}) {
+    streamCallLog.add('startVideoRecording');
+    return super
+        .startVideoRecording(cameraId, maxVideoDuration: maxVideoDuration);
+  }
+
+  @override
+  Future<void> startVideoCapturing(VideoCaptureOptions options) {
+    streamCallLog.add('startVideoCapturing');
+    return super.startVideoCapturing(options);
+  }
+
   void _onFrameStreamListen() {
     streamCallLog.add('listen');
   }

packages/camera/camera/test/camera_preview_test.dart

@@ -98,7 +98,8 @@ class FakeController extends ValueNotifier<CameraValue>
   Future<void> startImageStream(onLatestImageAvailable onAvailable) async {}
 
   @override
-  Future<void> startVideoRecording() async {}
+  Future<void> startVideoRecording(
+      {onLatestImageAvailable? onAvailable}) async {}
 
   @override
   Future<void> stopImageStream() async {}

packages/camera/camera/test/camera_test.dart

@@ -336,30 +336,6 @@ void main() {
           )));
     });
 
-    test(
-        'startVideoRecording() throws $CameraException when already streaming images',
-        () async {
-      final CameraController cameraController = CameraController(
-          const CameraDescription(
-              name: 'cam',
-              lensDirection: CameraLensDirection.back,
-              sensorOrientation: 90),
-          ResolutionPreset.max);
-
-      await cameraController.initialize();
-
-      cameraController.value =
-          cameraController.value.copyWith(isStreamingImages: true);
-
-      expect(
-          cameraController.startVideoRecording(),
-          throwsA(isA<CameraException>().having(
-            (CameraException error) => error.description,
-            'A camera has started streaming images.',
-            'startVideoRecording was called while a camera was streaming images.',
-          )));
-    });
-
     test('getMaxZoomLevel() throws $CameraException when uninitialized',
         () async {
       final CameraController cameraController = CameraController(
@@ -1459,6 +1435,12 @@ class MockCameraPlatform extends Mock
           {Duration? maxVideoDuration}) =>
       Future<XFile>.value(mockVideoRecordingXFile);
 
+  @override
+  Future<void> startVideoCapturing(VideoCaptureOptions options) {
+    return startVideoRecording(options.cameraId,
+        maxVideoDuration: options.maxDuration);
+  }
+
   @override
   Future<void> lockCaptureOrientation(
           int? cameraId, DeviceOrientation? orientation) async =>

packages/camera/camera_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.10.1
+
+* Implements option to also stream when recording a video.
+
 ## 0.10.0+4
 
 * Upgrades `androidx.annotation` version to 1.5.0.

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/Camera.java

@@ -522,6 +522,21 @@ private void refreshPreviewCaptureSession(
     }
   }
 
+  private void startCapture(boolean record, boolean stream) throws CameraAccessException {
+    List<Surface> surfaces = new ArrayList<>();
+    Runnable successCallback = null;
+    if (record) {
+      surfaces.add(mediaRecorder.getSurface());
+      successCallback = () -> mediaRecorder.start();
+    }
+    if (stream) {
+      surfaces.add(imageStreamReader.getSurface());
+    }
+
+    createCaptureSession(
+        CameraDevice.TEMPLATE_RECORD, successCallback, surfaces.toArray(new Surface[0]));
+  }
+
   public void takePicture(@NonNull final Result result) {
     // Only take one picture at a time.
     if (cameraCaptureCallback.getCameraState() != CameraState.STATE_PREVIEW) {
@@ -731,29 +746,17 @@ private void unlockAutoFocus() {
             dartMessenger.error(flutterResult, errorCode, errorMessage, null));
   }
 
-  public void startVideoRecording(@NonNull Result result) {
-    final File outputDir = applicationContext.getCacheDir();
-    try {
-      captureFile = File.createTempFile("REC", ".mp4", outputDir);
-    } catch (IOException | SecurityException e) {
-      result.error("cannotCreateFile", e.getMessage(), null);
-      return;
-    }
-    try {
-      prepareMediaRecorder(captureFile.getAbsolutePath());
-    } catch (IOException e) {
-      recordingVideo = false;
-      captureFile = null;
-      result.error("videoRecordingFailed", e.getMessage(), null);
-      return;
+  public void startVideoRecording(
+      @NonNull Result result, @Nullable EventChannel imageStreamChannel) {
+    prepareRecording(result);
+
+    if (imageStreamChannel != null) {
+      setStreamHandler(imageStreamChannel);
     }
-    // Re-create autofocus feature so it's using video focus mode now.
-    cameraFeatures.setAutoFocus(
-        cameraFeatureFactory.createAutoFocusFeature(cameraProperties, true));
+
     recordingVideo = true;
     try {
-      createCaptureSession(
-          CameraDevice.TEMPLATE_RECORD, () -> mediaRecorder.start(), mediaRecorder.getSurface());
+      startCapture(true, imageStreamChannel != null);
       result.success(null);
     } catch (CameraAccessException e) {
       recordingVideo = false;
@@ -1073,21 +1076,10 @@ public void startPreview() throws CameraAccessException {
 
   public void startPreviewWithImageStream(EventChannel imageStreamChannel)
       throws CameraAccessException {
-    createCaptureSession(CameraDevice.TEMPLATE_RECORD, imageStreamReader.getSurface());
-    Log.i(TAG, "startPreviewWithImageStream");
-
-    imageStreamChannel.setStreamHandler(
-        new EventChannel.StreamHandler() {
-          @Override
-          public void onListen(Object o, EventChannel.EventSink imageStreamSink) {
-            setImageStreamImageAvailableListener(imageStreamSink);
-          }
+    setStreamHandler(imageStreamChannel);
 
-          @Override
-          public void onCancel(Object o) {
-            imageStreamReader.setOnImageAvailableListener(null, backgroundHandler);
-          }
-        });
+    startCapture(false, true);
+    Log.i(TAG, "startPreviewWithImageStream");
   }
 
   /**
@@ -1117,6 +1109,42 @@ public void onError(String errorCode, String errorMessage) {
     cameraCaptureCallback.setCameraState(CameraState.STATE_PREVIEW);
   }
 
+  private void prepareRecording(@NonNull Result result) {
+    final File outputDir = applicationContext.getCacheDir();
+    try {
+      captureFile = File.createTempFile("REC", ".mp4", outputDir);
+    } catch (IOException | SecurityException e) {
+      result.error("cannotCreateFile", e.getMessage(), null);
+      return;
+    }
+    try {
+      prepareMediaRecorder(captureFile.getAbsolutePath());
+    } catch (IOException e) {
+      recordingVideo = false;
+      captureFile = null;
+      result.error("videoRecordingFailed", e.getMessage(), null);
+      return;
+    }
+    // Re-create autofocus feature so it's using video focus mode now.
+    cameraFeatures.setAutoFocus(
+        cameraFeatureFactory.createAutoFocusFeature(cameraProperties, true));
+  }
+
+  private void setStreamHandler(EventChannel imageStreamChannel) {
+    imageStreamChannel.setStreamHandler(
+        new EventChannel.StreamHandler() {
+          @Override
+          public void onListen(Object o, EventChannel.EventSink imageStreamSink) {
+            setImageStreamImageAvailableListener(imageStreamSink);
+          }
+
+          @Override
+          public void onCancel(Object o) {
+            imageStreamReader.setOnImageAvailableListener(null, backgroundHandler);
+          }
+        });
+  }
+
   private void setImageStreamImageAvailableListener(final EventChannel.EventSink imageStreamSink) {
     imageStreamReader.setOnImageAvailableListener(
         reader -> {