[camera] Limit video length with maxVideoDuration on startVideoRecording

packages/camera/camera/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.6.7
+
+* Added maxVideoDuration to startVideoRecording to limit the length of a recording. 
+
 ## 0.6.6
 
 * Adds auto focus support for Android and iOS implementations.

packages/camera/camera/README.md

@@ -47,7 +47,7 @@ It's important to note that the `MediaRecorder` class is not working properly on
 
 ### Handling Lifecycle states
 
-As of version [0.5.0](https://github.com/flutter/plugins/blob/master/packages/camera/CHANGELOG.md#050) of the camera plugin, lifecycle changes are no longer handled by the plugin. This means developers are now responsible to control camera resources when the lifecycle state is updated. Failure to do so might lead to unexpected behavior (for example as described in issue [#39109](https://github.com/flutter/flutter/issues/39109)). Handling lifecycle changes can be done by overriding the `didChangeAppLifecycleState` method like so:
+As of version [0.5.0](https://github.com/flutter/plugins/blob/master/packages/camera/camera/CHANGELOG.md#050) of the camera plugin, lifecycle changes are no longer handled by the plugin. This means developers are now responsible to control camera resources when the lifecycle state is updated. Failure to do so might lead to unexpected behavior (for example as described in issue [#39109](https://github.com/flutter/flutter/issues/39109)). Handling lifecycle changes can be done by overriding the `didChangeAppLifecycleState` method like so:
 
 ```dart
   @override
@@ -66,6 +66,33 @@ As of version [0.5.0](https://github.com/flutter/plugins/blob/master/packages/ca
   }
 ```
 
+As of version [0.6.5](https://github.com/flutter/plugins/blob/master/packages/camera/camera/CHANGELOG.md#065) the startVideoRecording method can be used with the maxVideoDuration. To do this the result of the recording needs to be retrieved by calling controller.onCameraTimeLimitReachedEvent which accepts a callback to retrieve the XFile result. Like so:
+
+```dart
+    Future<void> startVideoRecording() async {
+      if (!controller.value.isInitialized) {
+        showInSnackBar('Error: select a camera first.');
+        return;
+      }
+
+      if (controller.value.isRecordingVideo) {
+        // A recording is already started, do nothing.
+        return;
+      }
+
+      try {
+        await controller.startVideoRecording(
+            maxVideoDuration: const Duration(milliseconds: 5000),
+        );
+        controller.onCameraTimeLimitReachedEvent(onCameraTimeLimitReached: (XFile file) {
+          //Handle the XFile
+        });
+      } on CameraException catch (e) {
+        _showCameraException(e);
+        return;
+      }
+    }
+```
 ### Example
 
 Here is a small example flutter app displaying a full screen camera preview.
@@ -122,7 +149,7 @@ class _CameraAppState extends State<CameraApp> {
 }
 ```
 
-For a more elaborate usage example see [here](https://github.com/flutter/plugins/tree/master/packages/camera/example).
+For a more elaborate usage example see [here](https://github.com/flutter/plugins/tree/master/packages/camera/camera/example).
 
 *Note*: This plugin is still under development, and some APIs might not be available yet.
 [Feedback welcome](https://github.com/flutter/flutter/issues) and

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

@@ -4,6 +4,7 @@
 
 package io.flutter.plugins.camera;
 
+import static android.media.MediaRecorder.MEDIA_RECORDER_INFO_MAX_DURATION_REACHED;
 import static android.view.OrientationEventListener.ORIENTATION_UNKNOWN;
 import static io.flutter.plugins.camera.CameraUtils.computeBestPreviewSize;
 
@@ -106,6 +107,7 @@ public class Camera {
   private int exposureOffset;
   private boolean useAutoFocus = true;
   private Range<Integer> fpsRange;
+  private Integer maxDurationLimit;
 
   private static final HashMap<String, Integer> supportedImageFormats;
   // Current supported outputs
@@ -187,16 +189,21 @@ private void initFps(CameraCharacteristics cameraCharacteristics) {
     Log.i("Camera", "[FPS Range] is:" + fpsRange);
   }
 
-  private void prepareMediaRecorder(String outputFilePath) throws IOException {
+  private void prepareMediaRecorder(String outputFilePath, Integer maxVideoDuration)
+      throws IOException {
     if (mediaRecorder != null) {
       mediaRecorder.release();
     }
 
-    mediaRecorder =
+    MediaRecorderBuilder mediaRecorderBuilder =
         new MediaRecorderBuilder(recordingProfile, outputFilePath)
             .setEnableAudio(enableAudio)
-            .setMediaOrientation(getMediaOrientation())
-            .build();
+            .setMediaOrientation(getMediaOrientation());
+
+    if (maxVideoDuration != null) {
+      mediaRecorderBuilder.setMaxVideoDuration(maxVideoDuration);
+    }
+    mediaRecorder = mediaRecorderBuilder.build();
   }
 
   @SuppressLint("MissingPermission")
@@ -603,8 +610,9 @@ private void unlockAutoFocus() {
         (errorCode, errorMessage) -> pictureCaptureRequest.error(errorCode, errorMessage, null));
   }
 
-  public void startVideoRecording(Result result) {
+  public void startVideoRecording(Result result, Integer maxVideoDuration) {
     final File outputDir = applicationContext.getCacheDir();
+    maxDurationLimit = maxVideoDuration;
     try {
       videoRecordingFile = File.createTempFile("REC", ".mp4", outputDir);
     } catch (IOException | SecurityException e) {
@@ -613,10 +621,27 @@ public void startVideoRecording(Result result) {
     }
 
     try {
-      prepareMediaRecorder(videoRecordingFile.getAbsolutePath());
+      prepareMediaRecorder(videoRecordingFile.getAbsolutePath(), maxVideoDuration);
       recordingVideo = true;
       createCaptureSession(
           CameraDevice.TEMPLATE_RECORD, () -> mediaRecorder.start(), mediaRecorder.getSurface());
+      if (maxVideoDuration != null) {
+        mediaRecorder.setOnInfoListener(
+            (mr, what, extra) -> {
+              if (what == MEDIA_RECORDER_INFO_MAX_DURATION_REACHED) {
+                try {
+                  dartMessenger.sendVideoRecordedEvent(
+                      videoRecordingFile.getAbsolutePath(), maxVideoDuration);
+                  recordingVideo = false;
+                  videoRecordingFile = null;
+                  maxDurationLimit = null;
+                  resetCaptureSession();
+                } catch (CameraAccessException e) {
+                  result.error("videoRecordingFailed", e.getMessage(), null);
+                }
+              }
+            });
+      }
       result.success(null);
     } catch (CameraAccessException | IOException e) {
       recordingVideo = false;
@@ -625,6 +650,18 @@ public void startVideoRecording(Result result) {
     }
   }
 
+  public void resetCaptureSession() throws CameraAccessException {
+    try {
+      cameraCaptureSession.abortCaptures();
+      mediaRecorder.stop();
+    } catch (IllegalStateException e) {
+      // Ignore exceptions and try to continue (chances are camera session already aborted capture)
+    }
+
+    mediaRecorder.reset();
+    startPreview();
+  }
+
   public void stopVideoRecording(@NonNull final Result result) {
     if (!recordingVideo) {
       result.success(null);
@@ -634,18 +671,11 @@ public void stopVideoRecording(@NonNull final Result result) {
     try {
       recordingVideo = false;
 
-      try {
-        cameraCaptureSession.abortCaptures();
-        mediaRecorder.stop();
-      } catch (CameraAccessException | IllegalStateException e) {
-        // Ignore exceptions and try to continue (changes are camera session already aborted capture)
-      }
-
-      mediaRecorder.reset();
-      startPreview();
-      result.success(videoRecordingFile.getAbsolutePath());
+      resetCaptureSession();
+      dartMessenger.sendVideoRecordedEvent(videoRecordingFile.getAbsolutePath(), maxDurationLimit);
+      maxDurationLimit = null;
       videoRecordingFile = null;
-    } catch (CameraAccessException | IllegalStateException e) {
+    } catch (CameraAccessException e) {
       result.error("videoRecordingFailed", e.getMessage(), null);
     }
   }

packages/camera/camera/android/src/main/java/io/flutter/plugins/camera/DartMessenger.java

@@ -20,6 +20,7 @@ enum EventType {
     ERROR,
     CAMERA_CLOSING,
     INITIALIZED,
+    VIDEO_RECORDED,
   }
 
   DartMessenger(BinaryMessenger messenger, long cameraId) {
@@ -53,6 +54,17 @@ void sendCameraInitializedEvent(
         });
   }
 
+  void sendVideoRecordedEvent(String path, Integer maxVideoDuration) {
+    this.send(
+        EventType.VIDEO_RECORDED,
+        new HashMap<String, Object>() {
+          {
+            if (path != null) put("path", path);
+            if (maxVideoDuration != null) put("maxVideoDuration", maxVideoDuration);
+          }
+        });
+  }
+
   void sendCameraClosingEvent() {
     send(EventType.CAMERA_CLOSING);
   }

packages/camera/camera/android/src/main/java/io/flutter/plugins/camera/MethodCallHandlerImpl.java

@@ -111,7 +111,7 @@ public void onMethodCall(@NonNull MethodCall call, @NonNull final Result result)
         }
       case "startVideoRecording":
         {
-          camera.startVideoRecording(result);
+          camera.startVideoRecording(result, call.argument("maxVideoDuration"));
           break;
         }
       case "stopVideoRecording":

packages/camera/camera/android/src/main/java/io/flutter/plugins/camera/media/MediaRecorderBuilder.java

@@ -22,6 +22,7 @@ MediaRecorder makeMediaRecorder() {
 
   private boolean enableAudio;
   private int mediaOrientation;
+  private int maxVideoDuration;
 
   public MediaRecorderBuilder(
       @NonNull CamcorderProfile recordingProfile, @NonNull String outputFilePath) {
@@ -47,6 +48,11 @@ public MediaRecorderBuilder setMediaOrientation(int orientation) {
     return this;
   }
 
+  public MediaRecorderBuilder setMaxVideoDuration(int maxVideoDuration) {
+    this.maxVideoDuration = maxVideoDuration;
+    return this;
+  }
+
   public MediaRecorder build() throws IOException {
     MediaRecorder mediaRecorder = recorderFactory.makeMediaRecorder();
 
@@ -67,6 +73,8 @@ public MediaRecorder build() throws IOException {
     mediaRecorder.setOutputFile(outputFilePath);
     mediaRecorder.setOrientationHint(this.mediaOrientation);
 
+    mediaRecorder.setMaxDuration(maxVideoDuration);
+
     mediaRecorder.prepare();
 
     return mediaRecorder;

packages/camera/camera/example/lib/main.dart

@@ -571,6 +571,10 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
 
     try {
       await controller.initialize();
+      controller.onVideoRecordedEvent().listen((VideoRecordedEvent event) {
+        // Handle VideoRecordedEvent
+        debugPrint('event is stream ${event.file.path}');
+      });
       _minAvailableExposureOffset = await controller.getMinExposureOffset();
       _maxAvailableExposureOffset = await controller.getMaxExposureOffset();
       _maxAvailableZoom = await controller.getMaxZoomLevel();
@@ -663,6 +667,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
 
   void onStopButtonPressed() {
     stopVideoRecording().then((file) {
+      debugPrint('file after future ${file.path}');
       if (mounted) setState(() {});
       if (file != null) {
         showInSnackBar('Video recorded to ${file.path}');
@@ -698,7 +703,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
     }
 
     try {
-      await controller.startVideoRecording();
+      await controller.startVideoRecording(maxVideoDuration: null);
     } on CameraException catch (e) {
       _showCameraException(e);
       return;

packages/camera/camera/ios/Classes/CameraPlugin.m

@@ -751,7 +751,8 @@ - (CVPixelBufferRef)copyPixelBuffer {
   return pixelBuffer;
 }
 
-- (void)startVideoRecordingWithResult:(FlutterResult)result {
+- (void)startVideoRecordingWithResult:(FlutterResult)result
+                     maxVideoDuration:(int64_t)maxVideoDuration {
   if (!_isRecording) {
     NSError *error;
     _videoRecordingPath = [self getTemporaryFilePathWithExtension:@"mp4"
@@ -766,6 +767,14 @@ - (void)startVideoRecordingWithResult:(FlutterResult)result {
       result([FlutterError errorWithCode:@"IOError" message:@"Setup Writer Failed" details:nil]);
       return;
     }
+    if (maxVideoDuration != 0) {
+      dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(maxVideoDuration * NSEC_PER_MSEC)),
+                     dispatch_get_main_queue(), ^{
+                       if (self->_isRecording) {
+                         [self stopVideoRecording:maxVideoDuration];
+                       }
+                     });
+    }
     _isRecording = YES;
     _isRecordingPaused = NO;
     _videoTimeOffset = CMTimeMake(0, 1);
@@ -778,27 +787,27 @@ - (void)startVideoRecordingWithResult:(FlutterResult)result {
   }
 }
 
-- (void)stopVideoRecordingWithResult:(FlutterResult)result {
+- (void)stopVideoRecording:(int64_t)maxVideoDuration {
   if (_isRecording) {
     _isRecording = NO;
     if (_videoWriter.status != AVAssetWriterStatusUnknown) {
       [_videoWriter finishWritingWithCompletionHandler:^{
         if (self->_videoWriter.status == AVAssetWriterStatusCompleted) {
-          result(self->_videoRecordingPath);
+          [self->_methodChannel invokeMethod:@"video_recorded"
+                                   arguments:@{
+                                     @"path" : self->_videoRecordingPath,
+                                     @"maxVideoDuration" : @(maxVideoDuration),
+                                   }];
+
           self->_videoRecordingPath = nil;
         } else {
-          result([FlutterError errorWithCode:@"IOError"
-                                     message:@"AVAssetWriter could not finish writing!"
-                                     details:nil]);
+          [self->_methodChannel invokeMethod:errorMethod
+                                   arguments:@"AVAssetWriter could not finish writing!"];
         }
       }];
     }
   } else {
-    NSError *error =
-        [NSError errorWithDomain:NSCocoaErrorDomain
-                            code:NSURLErrorResourceUnavailable
-                        userInfo:@{NSLocalizedDescriptionKey : @"Video is not recording!"}];
-    result(getFlutterError(error));
+    [self->_methodChannel invokeMethod:errorMethod arguments:@"Video is not recording!"];
   }
 }
 
@@ -1282,9 +1291,15 @@ - (void)handleMethodCallAsync:(FlutterMethodCall *)call result:(FlutterResult)re
       [_camera setUpCaptureSessionForAudio];
       result(nil);
     } else if ([@"startVideoRecording" isEqualToString:call.method]) {
-      [_camera startVideoRecordingWithResult:result];
+      if ([call.arguments[@"maxVideoDuration"] class] != [NSNull class]) {
+        [_camera startVideoRecordingWithResult:result
+                              maxVideoDuration:((NSNumber *)call.arguments[@"maxVideoDuration"])
+                                                   .intValue];
+      } else {
+        [_camera startVideoRecordingWithResult:result maxVideoDuration:0];
+      }
     } else if ([@"stopVideoRecording" isEqualToString:call.method]) {
-      [_camera stopVideoRecordingWithResult:result];
+      [_camera stopVideoRecording:0];
     } else if ([@"pauseVideoRecording" isEqualToString:call.method]) {
       [_camera pauseVideoRecordingWithResult:result];
     } else if ([@"resumeVideoRecording" isEqualToString:call.method]) {

packages/camera/camera/lib/camera.dart

@@ -11,6 +11,7 @@ export 'package:camera_platform_interface/camera_platform_interface.dart'
         CameraDescription,
         CameraException,
         CameraLensDirection,
+        VideoRecordedEvent,
         FlashMode,
         ExposureMode,
         FocusMode,