Adds support for video stabilization to camera_platform_interface

- Adds getSupportedVideoStabilizationModes() and
  setVideoStabilizationMode() methods to CameraPlatform.

- Adds VideoStabilizationMode enum to represent an abstraction of the
  available video stabilization modes, meant for Android and iOS,
  mapped as follows:

  /// Video stabilization is disabled.
  off,

  /// Least stabilized video stabilization mode with the least latency.
  level1,

  /// More stabilized video with more latency.
  level2,

  /// Most stabilized video with the most latency.
  level3;

Author: ruicraveiro

packages/camera/camera_platform_interface/AUTHORS

@@ -65,3 +65,4 @@ Anton Borries <mail@antonborri.es>
 Alex Li <google@alexv525.com>
 Rahul Raj <64.rahulraj@gmail.com>
 Mairramer <mairramer.dasilva28@hotmail.com>
+Rui Craveiro <ruicraveiro@squarealfa.com>

packages/camera/camera_platform_interface/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.12.0
+
+* Adds support for video stabilization.
+
 ## 2.11.0
 
 * Adds a flag to configure a recording to be persistent across camera changes. See
@@ -20,6 +24,7 @@
   most platforms, and there is no plan to implement it in the future.
 * Updates minimum supported SDK version to Flutter 3.16/Dart 3.2.
 
+
 ## 2.7.4
 
 * Updates minimum supported SDK version to Flutter 3.13/Dart 3.1.

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

@@ -281,6 +281,34 @@ abstract class CameraPlatform extends PlatformInterface {
     throw UnimplementedError('setZoomLevel() is not implemented.');
   }
 
+  /// Gets a list of video stabilization modes that are supported for the selected camera.
+  Future<Iterable<VideoStabilizationMode>> getSupportedVideoStabilizationModes(
+    int cameraId,
+  ) async => <VideoStabilizationMode>[];
+
+  /// Sets the video stabilization mode for the selected camera.
+  Future<void> setVideoStabilizationMode(
+    int cameraId,
+    VideoStabilizationMode mode,
+  ) async {
+    throw UnimplementedError('setVideoStabilizationMode() is not implemented.');
+  }
+
+  /// Gets the fallback mode of video stabilization [mode].
+  ///
+  /// This method returns the video stabilization mode that [setVideoStabilizationMode]
+  /// should set when the device does not support the given [mode].
+  static VideoStabilizationMode? getFallbackVideoStabilizationMode(
+    VideoStabilizationMode mode,
+  ) {
+    return switch (mode) {
+      VideoStabilizationMode.off => null,
+      VideoStabilizationMode.level1 => VideoStabilizationMode.off,
+      VideoStabilizationMode.level2 => VideoStabilizationMode.level1,
+      VideoStabilizationMode.level3 => VideoStabilizationMode.level2,
+    };
+  }
+
   /// Pause the active preview on the current frame for the selected camera.
   Future<void> pausePreview(int cameraId) {
     throw UnimplementedError('pausePreview() is not implemented.');

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

@@ -13,3 +13,4 @@ export 'image_format_group.dart';
 export 'media_settings.dart';
 export 'resolution_preset.dart';
 export 'video_capture_options.dart';
+export 'video_stabilization_mode.dart';

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

@@ -0,0 +1,18 @@
+// 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.
+
+/// The possible video stabilization modes that can be capturing video.
+enum VideoStabilizationMode {
+  /// Video stabilization is disabled.
+  off,
+
+  /// Least stabilized video stabilization mode with the least latency.
+  level1,
+
+  /// More stabilized video with more latency.
+  level2,
+
+  /// Most stabilized video with the most latency.
+  level3,
+}

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: 2.11.0
+version: 2.12.0
 
 environment:
   sdk: ^3.7.0

packages/camera/camera_platform_interface/test/camera_platform_interface_test.dart

@@ -531,6 +531,42 @@ void main() {
         expect(cameraPlatform.supportsImageStreaming(), false);
       },
     );
+
+    test('getFallbackViewStabilizationMode returns level2 for mode level3', () {
+      final VideoStabilizationMode? fallbackMode =
+          CameraPlatform.getFallbackVideoStabilizationMode(
+            VideoStabilizationMode.level3,
+          );
+
+      expect(fallbackMode, VideoStabilizationMode.level2);
+    });
+
+    test('getFallbackViewStabilizationMode returns level1 for mode level2', () {
+      final VideoStabilizationMode? fallbackMode =
+          CameraPlatform.getFallbackVideoStabilizationMode(
+            VideoStabilizationMode.level2,
+          );
+
+      expect(fallbackMode, VideoStabilizationMode.level1);
+    });
+
+    test('getFallbackViewStabilizationMode returns off for mode level1', () {
+      final VideoStabilizationMode? fallbackMode =
+          CameraPlatform.getFallbackVideoStabilizationMode(
+            VideoStabilizationMode.level1,
+          );
+
+      expect(fallbackMode, VideoStabilizationMode.off);
+    });
+
+    test('getFallbackViewStabilizationMode returns null for mode off', () {
+      final VideoStabilizationMode? fallbackMode =
+          CameraPlatform.getFallbackVideoStabilizationMode(
+            VideoStabilizationMode.off,
+          );
+
+      expect(fallbackMode, null);
+    });
   });
 
   group('exports', () {

packages/camera/camera_platform_interface/test/types/video_stabilization_mode_test.dart

@@ -0,0 +1,23 @@
+// 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.
+
+import 'package:camera_platform_interface/src/types/video_stabilization_mode.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('VideoStabilizationMode should contain 4 options', () {
+    const List<VideoStabilizationMode> values = VideoStabilizationMode.values;
+
+    expect(values.length, 4);
+  });
+
+  test('VideoStabilizationMode enum should have items in correct index', () {
+    const List<VideoStabilizationMode> values = VideoStabilizationMode.values;
+
+    expect(values[0], VideoStabilizationMode.off);
+    expect(values[1], VideoStabilizationMode.level1);
+    expect(values[2], VideoStabilizationMode.level2);
+    expect(values[3], VideoStabilizationMode.level3);
+  });
+}