[camera] Add setJpegImageQuality for JPEG compression control

Adds setJpegImageQuality(int quality) across all camera platform
implementations (Android, Android CameraX, iOS AVFoundation) and
the app-facing camera package. This allows controlling the JPEG
compression quality (1-100) for still image capture.

Platform interface changes were landed separately in #11454.

Author: Bolling88

packages/camera/camera/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.12.1
+
+* Adds `setJpegImageQuality` for controlling JPEG compression quality.
+
 ## 0.12.0+1
 
 * Makes `Optional.of` constructor `const`.

packages/camera/camera/example/pubspec.yaml

@@ -31,3 +31,8 @@ dev_dependencies:
 
 flutter:
   uses-material-design: true
+# FOR TESTING AND INITIAL REVIEW ONLY. DO NOT MERGE.
+# See https://github.com/flutter/flutter/blob/master/docs/ecosystem/contributing/README.md#changing-federated-plugins
+dependency_overrides:
+  camera_android_camerax: {path: ../../../../packages/camera/camera_android_camerax}
+  camera_avfoundation: {path: ../../../../packages/camera/camera_avfoundation}

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

@@ -994,6 +994,24 @@ class CameraController extends ValueNotifier<CameraValue> {
     }
   }
 
+  /// Sets the JPEG compression quality for still image capture.
+  ///
+  /// The [quality] must be between 1 (lowest) and 100 (highest).
+  Future<void> setJpegImageQuality(int quality) async {
+    if (quality < 1 || quality > 100) {
+      throw ArgumentError.value(
+        quality,
+        'quality',
+        'Must be between 1 and 100.',
+      );
+    }
+    try {
+      await CameraPlatform.instance.setJpegImageQuality(_cameraId, quality);
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
+  }
+
   /// Check whether the camera platform supports image streaming.
   bool supportsImageStreaming() =>
       CameraPlatform.instance.supportsImageStreaming();

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/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
-version: 0.12.0+1
+version: 0.12.1
 
 environment:
   sdk: ^3.9.0
@@ -21,9 +21,9 @@ flutter:
         default_package: camera_web
 
 dependencies:
-  camera_android_camerax: ^0.7.0
-  camera_avfoundation: ^0.10.0
-  camera_platform_interface: ^2.12.0
+  camera_android_camerax: ^0.7.1
+  camera_avfoundation: ^0.10.1
+  camera_platform_interface: ^2.13.0
   camera_web: ^0.3.3
   flutter:
     sdk: flutter
@@ -38,3 +38,8 @@ dev_dependencies:
 
 topics:
   - camera
+# FOR TESTING AND INITIAL REVIEW ONLY. DO NOT MERGE.
+# See https://github.com/flutter/flutter/blob/master/docs/ecosystem/contributing/README.md#changing-federated-plugins
+dependency_overrides:
+  camera_android_camerax: {path: ../../../packages/camera/camera_android_camerax}
+  camera_avfoundation: {path: ../../../packages/camera/camera_avfoundation}

packages/camera/camera/test/camera_preview_test.dart

@@ -149,6 +149,9 @@ class FakeController extends ValueNotifier<CameraValue>
   Future<Iterable<VideoStabilizationMode>>
   getSupportedVideoStabilizationModes() async => <VideoStabilizationMode>[];
 
+  @override
+  Future<void> setJpegImageQuality(int quality) async {}
+
   @override
   bool supportsImageStreaming() => true;
 }

packages/camera/camera/test/camera_test.dart

@@ -885,6 +885,83 @@ void main() {
       },
     );
 
+    test('setJpegImageQuality() calls CameraPlatform', () async {
+      final cameraController = CameraController(
+        const CameraDescription(
+          name: 'cam',
+          lensDirection: CameraLensDirection.back,
+          sensorOrientation: 90,
+        ),
+        ResolutionPreset.max,
+      );
+      await cameraController.initialize();
+
+      await cameraController.setJpegImageQuality(50);
+
+      verify(
+        CameraPlatform.instance.setJpegImageQuality(cameraController.cameraId, 50),
+      ).called(1);
+    });
+
+    test(
+      'setJpegImageQuality() throws CameraException on PlatformException',
+      () async {
+        final cameraController = CameraController(
+          const CameraDescription(
+            name: 'cam',
+            lensDirection: CameraLensDirection.back,
+            sensorOrientation: 90,
+          ),
+          ResolutionPreset.max,
+        );
+        await cameraController.initialize();
+
+        when(
+          CameraPlatform.instance.setJpegImageQuality(
+            cameraController.cameraId,
+            50,
+          ),
+        ).thenThrow(
+          PlatformException(
+            code: 'TEST_ERROR',
+            message: 'This is a test error message',
+          ),
+        );
+
+        expect(
+          cameraController.setJpegImageQuality(50),
+          throwsA(
+            isA<CameraException>().having(
+              (CameraException error) => error.description,
+              'TEST_ERROR',
+              'This is a test error message',
+            ),
+          ),
+        );
+      },
+    );
+
+    test('setJpegImageQuality() throws ArgumentError for invalid values', () async {
+      final cameraController = CameraController(
+        const CameraDescription(
+          name: 'cam',
+          lensDirection: CameraLensDirection.back,
+          sensorOrientation: 90,
+        ),
+        ResolutionPreset.max,
+      );
+      await cameraController.initialize();
+
+      expect(
+        () => cameraController.setJpegImageQuality(0),
+        throwsA(isA<ArgumentError>()),
+      );
+      expect(
+        () => cameraController.setJpegImageQuality(101),
+        throwsA(isA<ArgumentError>()),
+      );
+    });
+
     test('setExposureMode() calls $CameraPlatform', () async {
       final cameraController = CameraController(
         const CameraDescription(
@@ -4152,6 +4229,12 @@ class MockCameraPlatform extends Mock
   ) async => super.noSuchMethod(
     Invocation.method(#setVideoStabilizationMode, <Object?>[cameraId, mode]),
   );
+
+  @override
+  Future<void> setJpegImageQuality(int? cameraId, int? quality) async =>
+      super.noSuchMethod(
+        Invocation.method(#setJpegImageQuality, <Object?>[cameraId, quality]),
+      );
 }
 
 class MockCameraDescription extends CameraDescription {

packages/camera/camera_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.10.11
+
+* Adds `setJpegImageQuality` for controlling JPEG compression quality.
+
 ## 0.10.10+16
 
 * Updates build files from Groovy to Kotlin.

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

@@ -53,6 +53,7 @@
 import io.flutter.plugins.camera.features.flash.FlashMode;
 import io.flutter.plugins.camera.features.focuspoint.FocusPointFeature;
 import io.flutter.plugins.camera.features.fpsrange.FpsRangeFeature;
+import io.flutter.plugins.camera.features.jpegquality.JpegQualityFeature;
 import io.flutter.plugins.camera.features.resolution.ResolutionFeature;
 import io.flutter.plugins.camera.features.resolution.ResolutionPreset;
 import io.flutter.plugins.camera.features.sensororientation.DeviceOrientationManager;
@@ -1416,6 +1417,20 @@ public void setDescriptionWhileRecording(CameraProperties properties) {
     }
   }
 
+  /**
+   * Sets the JPEG compression quality for still image capture.
+   *
+   * @param quality JPEG quality value between 1 and 100.
+   */
+  public void setJpegImageQuality(@NonNull Long quality) {
+    JpegQualityFeature jpegQualityFeature = cameraFeatures.getJpegQuality();
+    if (jpegQualityFeature == null) {
+      jpegQualityFeature = cameraFeatureFactory.createJpegQualityFeature(cameraProperties);
+      cameraFeatures.setJpegQuality(jpegQualityFeature);
+    }
+    jpegQualityFeature.setValue(quality.intValue());
+  }
+
   public void dispose() {
     Log.i(TAG, "dispose");
 

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

@@ -343,6 +343,11 @@ public void setDescriptionWhileRecording(@NonNull String cameraName) {
     }
   }
 
+  @Override
+  public void setJpegImageQuality(@NonNull Long quality) {
+    camera.setJpegImageQuality(quality);
+  }
+
   @Override
   public void dispose() {
     if (camera != null) {

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

@@ -1079,6 +1079,9 @@ void create(
      */
     void setDescriptionWhileRecording(@NonNull String description);
 
+    /** Sets the JPEG compression quality for still image capture. */
+    void setJpegImageQuality(@NonNull Long quality);
+
     /** The codec used by CameraApi. */
     static @NonNull MessageCodec<Object> getCodec() {
       return PigeonCodec.INSTANCE;
@@ -1809,6 +1812,31 @@ public void error(Throwable error) {
           channel.setMessageHandler(null);
         }
       }
+      {
+        BasicMessageChannel<Object> channel =
+            new BasicMessageChannel<>(
+                binaryMessenger,
+                "dev.flutter.pigeon.camera_android.CameraApi.setJpegImageQuality"
+                    + messageChannelSuffix,
+                getCodec());
+        if (api != null) {
+          channel.setMessageHandler(
+              (message, reply) -> {
+                ArrayList<Object> wrapped = new ArrayList<>();
+                ArrayList<Object> args = (ArrayList<Object>) message;
+                Long qualityArg = (Long) args.get(0);
+                try {
+                  api.setJpegImageQuality(qualityArg);
+                  wrapped.add(0, null);
+                } catch (Throwable exception) {
+                  wrapped = wrapError(exception);
+                }
+                reply.reply(wrapped);
+              });
+        } else {
+          channel.setMessageHandler(null);
+        }
+      }
     }
   }