| /* |
| * Copyright 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package androidx.camera.core; |
| |
| import androidx.annotation.NonNull; |
| import androidx.annotation.RequiresApi; |
| import androidx.annotation.RestrictTo; |
| import androidx.camera.core.impl.CameraConfig; |
| import androidx.camera.core.impl.ExtendedCameraConfigProviderStore; |
| import androidx.camera.core.impl.Identifier; |
| |
| import java.util.List; |
| |
| /** |
| * An interface for filtering cameras. |
| */ |
| @RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java |
| public interface CameraFilter { |
| /** |
| * Default identifier of camera filter. |
| * |
| */ |
| @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) |
| Identifier DEFAULT_ID = Identifier.create(new Object()); |
| |
| /** |
| * Filters a list of {@link CameraInfo}s and returns those matching the requirements. |
| * |
| * <p>If the output list contains CameraInfos not in the input list, when used by a |
| * {@link androidx.camera.core.CameraSelector} then it will result in an |
| * IllegalArgumentException thrown when calling bindToLifecycle. |
| * |
| * <p>The CameraInfo that has lower index in the list has higher priority. When used by |
| * {@link androidx.camera.core.CameraSelector.Builder#addCameraFilter(CameraFilter)}, the |
| * available cameras will be filtered by all {@link CameraFilter}s by the order they were |
| * added. The first camera in the result will be selected if there are multiple cameras left. |
| * |
| * @param cameraInfos An unmodifiable list of {@link CameraInfo}s being filtered. |
| * @return The output list of {@link CameraInfo}s that match the requirements. Users are |
| * expected to create a new list to return with. |
| * |
| * @throws IllegalArgumentException If the device cannot return a valid lens facing value, |
| * it will throw this exception. |
| */ |
| @NonNull |
| List<CameraInfo> filter(@NonNull List<CameraInfo> cameraInfos); |
| |
| /** |
| * Returns the id of this camera filter. |
| * |
| * <p>A camera filter can be associated with a set of camera configuration options. This |
| * means a camera filter's {@link Identifier} can be mapped to a unique {@link CameraConfig}. |
| * An example of this is extension modes, where a camera filter can represent an extension |
| * mode, and each extension mode adds a set of camera configurations to the camera that |
| * supports it. {@link ExtendedCameraConfigProviderStore#getConfigProvider(Object)} allows |
| * retrieving the {@link CameraConfig} of an extension mode given the {@link Identifier} of |
| * its camera filter. |
| * |
| */ |
| @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) |
| @NonNull |
| default Identifier getIdentifier() { |
| return DEFAULT_ID; |
| } |
| } |