[camera] CameraPlatform.createCameraWithSettings

packages/camera/camera_platform_interface/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.6.0
+
+* Adds support to control video fps and bitrate. See `CameraPlatform.createCameraWithSettings`.
+
 ## 2.5.2
 
 * Adds pub topics to package metadata.

packages/camera/camera_platform_interface/lib/camera_platform_interface.dart

@@ -8,4 +8,5 @@ export 'package:cross_file/cross_file.dart';
 export 'src/events/camera_event.dart';
 export 'src/events/device_event.dart';
 export 'src/platform_interface/camera_platform.dart';
+export 'src/types/media_settings.dart';
 export 'src/types/types.dart';

packages/camera/camera_platform_interface/lib/src/method_channel/method_channel_camera.dart

@@ -88,15 +88,29 @@ class MethodChannelCamera extends CameraPlatform {
     CameraDescription cameraDescription,
     ResolutionPreset? resolutionPreset, {
     bool enableAudio = false,
-  }) async {
+  }) async =>
+      createCameraWithSettings(
+          cameraDescription,
+          MediaSettings(
+              resolutionPreset: resolutionPreset, enableAudio: enableAudio));
+
+  @override
+  Future<int> createCameraWithSettings(
+    CameraDescription cameraDescription,
+    MediaSettings mediaSettings,
+  ) async {
     try {
+      final ResolutionPreset? resolutionPreset = mediaSettings.resolutionPreset;
       final Map<String, dynamic>? reply = await _channel
           .invokeMapMethod<String, dynamic>('create', <String, dynamic>{
         'cameraName': cameraDescription.name,
         'resolutionPreset': resolutionPreset != null
-            ? _serializeResolutionPreset(resolutionPreset)
+            ? _serializeResolutionPreset(mediaSettings.resolutionPreset!)
             : null,
-        'enableAudio': enableAudio,
+        'fps': mediaSettings.fps,
+        'videoBitrate': mediaSettings.videoBitrate,
+        'audioBitrate': mediaSettings.audioBitrate,
+        'enableAudio': mediaSettings.enableAudio,
       });
 
       return reply!['cameraId']! as int;

packages/camera/camera_platform_interface/lib/src/platform_interface/camera_platform.dart

@@ -55,6 +55,16 @@ abstract class CameraPlatform extends PlatformInterface {
     throw UnimplementedError('createCamera() is not implemented.');
   }
 
+  /// Creates an uninitialized camera instance and returns the cameraId.
+  ///
+  /// Pass MediaSettings() for defaults
+  Future<int> createCameraWithSettings(
+    CameraDescription cameraDescription,
+    MediaSettings mediaSettings,
+  ) {
+    return createCamera(cameraDescription, mediaSettings.resolutionPreset);
+  }
+
   /// Initializes the camera on the device.
   ///
   /// [imageFormatGroup] is used to specify the image formatting used.

packages/camera/camera_platform_interface/lib/src/types/media_settings.dart

@@ -0,0 +1,77 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ignore_for_file: avoid_equals_and_hash_code_on_mutable_classes
+
+import 'resolution_preset.dart';
+
+/// Recording media settings.
+///
+/// Used in [CameraPlatform.createCameraWithSettings].
+/// Allows to tune recorded video parameters, such as resolution, frame rate, bitrate.
+/// If [fps], [videoBitrate] or [audioBitrate] are passed, they must be greater than zero.
+class MediaSettings {
+  /// Creates a [MediaSettings].
+  const MediaSettings({
+    this.resolutionPreset,
+    this.fps,
+    this.videoBitrate,
+    this.audioBitrate,
+    this.enableAudio = false,
+  })  : assert(fps == null || fps > 0, 'fps must be null or greater than zero'),
+        assert(videoBitrate == null || videoBitrate > 0,
+            'videoBitrate must be null or greater than zero'),
+        assert(audioBitrate == null || audioBitrate > 0,
+            'audioBitrate must be null or greater than zero');
+
+  /// [ResolutionPreset] affect the quality of video recording and image capture.
+  final ResolutionPreset? resolutionPreset;
+
+  /// Rate at which frames should be captured by the camera in frames per second.
+  final int? fps;
+
+  /// The video encoding bit rate for recording.
+  final int? videoBitrate;
+
+  /// The audio encoding bit rate for recording.
+  final int? audioBitrate;
+
+  /// Controls audio presence in recorded video.
+  final bool enableAudio;
+
+  @override
+  bool operator ==(Object other) {
+    if (identical(other, this)) {
+      return true;
+    }
+    if (other.runtimeType != runtimeType) {
+      return false;
+    }
+    return other is MediaSettings &&
+        resolutionPreset == other.resolutionPreset &&
+        fps == other.fps &&
+        videoBitrate == other.videoBitrate &&
+        audioBitrate == other.audioBitrate &&
+        enableAudio == other.enableAudio;
+  }
+
+  @override
+  int get hashCode => Object.hash(
+        resolutionPreset,
+        fps,
+        videoBitrate,
+        audioBitrate,
+        enableAudio,
+      );
+
+  @override
+  String toString() {
+    return 'MediaSettings{'
+        'resolutionPreset: $resolutionPreset, '
+        'fps: $fps, '
+        'videoBitrate: $videoBitrate, '
+        'audioBitrate: $audioBitrate, '
+        'enableAudio: $enableAudio}';
+  }
+}

packages/camera/camera_platform_interface/lib/src/types/types.dart

@@ -9,5 +9,6 @@ export 'exposure_mode.dart';
 export 'flash_mode.dart';
 export 'focus_mode.dart';
 export 'image_format_group.dart';
+export 'media_settings.dart';
 export 'resolution_preset.dart';
 export 'video_capture_options.dart';

packages/camera/camera_platform_interface/pubspec.yaml

@@ -4,7 +4,7 @@ repository: https://github.com/flutter/packages/tree/main/packages/camera/camera
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
 # NOTE: We strongly prefer non-breaking changes, even at the expense of a
 # less-clean API. See https://flutter.dev/go/platform-interface-breaking-changes
-version: 2.5.2
+version: 2.6.0
 
 environment:
   sdk: ">=2.19.0 <4.0.0"

packages/camera/camera_platform_interface/test/camera_platform_interface_test.dart

@@ -163,7 +163,33 @@ void main() {
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 0,
           ),
-          ResolutionPreset.high,
+          ResolutionPreset.low,
+        ),
+        throwsUnimplementedError,
+      );
+    });
+
+    test(
+        'Default implementation of createCameraWithSettings() should throw unimplemented error',
+        () {
+      // Arrange
+      final ExtendsCameraPlatform cameraPlatform = ExtendsCameraPlatform();
+
+      // Act & Assert
+      expect(
+        () => cameraPlatform.createCameraWithSettings(
+          const CameraDescription(
+            name: 'back',
+            lensDirection: CameraLensDirection.back,
+            sensorOrientation: 0,
+          ),
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+            enableAudio: true,
+          ),
         ),
         throwsUnimplementedError,
       );

packages/camera/camera_platform_interface/test/method_channel/method_channel_camera_test.dart

@@ -33,12 +33,17 @@ void main() {
         final MethodChannelCamera camera = MethodChannelCamera();
 
         // Act
-        final int cameraId = await camera.createCamera(
+        final int cameraId = await camera.createCameraWithSettings(
           const CameraDescription(
               name: 'Test',
               lensDirection: CameraLensDirection.back,
               sensorOrientation: 0),
-          ResolutionPreset.high,
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+          ),
         );
 
         // Assert
@@ -47,7 +52,10 @@ void main() {
             'create',
             arguments: <String, Object?>{
               'cameraName': 'Test',
-              'resolutionPreset': 'high',
+              'resolutionPreset': 'low',
+              'fps': 15,
+              'videoBitrate': 200000,
+              'audioBitrate': 32000,
               'enableAudio': false
             },
           ),
@@ -71,13 +79,19 @@ void main() {
 
         // Act
         expect(
-          () => camera.createCamera(
+          () => camera.createCameraWithSettings(
             const CameraDescription(
               name: 'Test',
               lensDirection: CameraLensDirection.back,
               sensorOrientation: 0,
             ),
-            ResolutionPreset.high,
+            const MediaSettings(
+              resolutionPreset: ResolutionPreset.low,
+              fps: 15,
+              videoBitrate: 200000,
+              audioBitrate: 32000,
+              enableAudio: true,
+            ),
           ),
           throwsA(
             isA<CameraException>()
@@ -105,13 +119,19 @@ void main() {
 
         // Act
         expect(
-          () => camera.createCamera(
+          () => camera.createCameraWithSettings(
             const CameraDescription(
               name: 'Test',
               lensDirection: CameraLensDirection.back,
               sensorOrientation: 0,
             ),
-            ResolutionPreset.high,
+            const MediaSettings(
+              resolutionPreset: ResolutionPreset.low,
+              fps: 15,
+              videoBitrate: 200000,
+              audioBitrate: 32000,
+              enableAudio: true,
+            ),
           ),
           throwsA(
             isA<CameraException>()
@@ -167,13 +187,19 @@ void main() {
               'initialize': null
             });
         final MethodChannelCamera camera = MethodChannelCamera();
-        final int cameraId = await camera.createCamera(
+        final int cameraId = await camera.createCameraWithSettings(
           const CameraDescription(
             name: 'Test',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 0,
           ),
-          ResolutionPreset.high,
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+            enableAudio: true,
+          ),
         );
 
         // Act
@@ -214,13 +240,19 @@ void main() {
             });
 
         final MethodChannelCamera camera = MethodChannelCamera();
-        final int cameraId = await camera.createCamera(
+        final int cameraId = await camera.createCameraWithSettings(
           const CameraDescription(
             name: 'Test',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 0,
           ),
-          ResolutionPreset.high,
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+            enableAudio: true,
+          ),
         );
         final Future<void> initializeFuture = camera.initializeCamera(cameraId);
         camera.cameraEventStreamController.add(CameraInitializedEvent(
@@ -262,13 +294,19 @@ void main() {
           },
         );
         camera = MethodChannelCamera();
-        cameraId = await camera.createCamera(
+        cameraId = await camera.createCameraWithSettings(
           const CameraDescription(
             name: 'Test',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 0,
           ),
-          ResolutionPreset.high,
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+            enableAudio: true,
+          ),
         );
         final Future<void> initializeFuture = camera.initializeCamera(cameraId);
         camera.cameraEventStreamController.add(CameraInitializedEvent(
@@ -432,13 +470,19 @@ void main() {
           },
         );
         camera = MethodChannelCamera();
-        cameraId = await camera.createCamera(
+        cameraId = await camera.createCameraWithSettings(
           const CameraDescription(
             name: 'Test',
             lensDirection: CameraLensDirection.back,
             sensorOrientation: 0,
           ),
-          ResolutionPreset.high,
+          const MediaSettings(
+            resolutionPreset: ResolutionPreset.low,
+            fps: 15,
+            videoBitrate: 200000,
+            audioBitrate: 32000,
+            enableAudio: true,
+          ),
         );
         final Future<void> initializeFuture = camera.initializeCamera(cameraId);
         camera.cameraEventStreamController.add(