相机应用可通过创建相机输入流调用并控制相机设备，创建不同类型的输出流，进而实现预览、拍照、录像等基础功能。
开发步骤
在创建相机设备输入之前需要先完成相机设备管理，详细开发步骤可参考上一篇文章。
创建相机输入流
通过cameraManager类的createCameraInput方法创建相机输入流，监听相机输入流错误事件并打开相机
import { camera } from '@kit.CameraKit';
import { BusinessError } from '@kit.BasicServicesKit';async function createInput(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager): Promise<camera.CameraInput | undefined> {// 创建相机输入流。let cameraInput: camera.CameraInput | undefined = undefined;try {cameraInput = cameraManager.createCameraInput(cameraDevice);} catch (error) {let err = error as BusinessError;console.error(`The createCameraInput call failed. error code: ${err.code}`);}if (cameraInput === undefined) {return undefined;}// 监听cameraInput错误信息。cameraInput.on('error', cameraDevice, (error: BusinessError) => {console.error(`Camera input error code: ${error.code}`);});// 打开相机。await cameraInput.open();return cameraInput;
}
获取相机支持的模式列表
调用getSupportedSceneModes方法，获取当前相机设备支持的所有模式列表SceneMode数组
function getSupportedSceneMode(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager): Array<camera.SceneMode> {// 获取相机设备支持的模式列表let sceneModeArray: Array<camera.SceneMode> = cameraManager.getSupportedSceneModes(cameraDevice);if (sceneModeArray != undefined && sceneModeArray.length > 0) {for (let index = 0; index < sceneModeArray.length; index++) {console.info('Camera SceneMode : ' + sceneModeArray[index]); }return sceneModeArray;} else {console.error("cameraManager.getSupportedSceneModes error");return [];}
}
相机支持的模式包括NORMAL_PHOTO（普通拍照模式）、NORMAL_VIDEO（普通录像模式）和SECURE_PHOTO（安全相机模式）。
获取相机支持的输出流
获取当前相机设备支持的所有输出流：通过getSupportedOutputCapability方法，获取当前相机设备支持的所有输出流，如预览流、拍照流、录像流等。输入CameraDevice和SceneMode，获取CameraOutputCapability相机输出能力，不同输出流的能力保存在CameraOutputCapability中的各个profile字段中
async function getSupportedOutputCapability(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager, sceneMode: camera.SceneMode): Promise<camera.CameraOutputCapability | undefined> {// 获取相机设备支持的输出流能力。let cameraOutputCapability: camera.CameraOutputCapability = cameraManager.getSupportedOutputCapability(cameraDevice, sceneMode);if (!cameraOutputCapability) {console.error("cameraManager.getSupportedOutputCapability error");return undefined;}console.info("outputCapability: " + JSON.stringify(cameraOutputCapability));// previewProfiles属性为获取当前设备支持的预览输出流。let previewProfilesArray: Array<camera.Profile> = cameraOutputCapability.previewProfiles;if (!previewProfilesArray) {console.error("getSupportedOutputCapability previewProfilesArray == null || undefined");}//photoProfiles属性为获取当前设备支持的拍照输出流。let photoProfilesArray: Array<camera.Profile> = cameraOutputCapability.photoProfiles;if (!photoProfilesArray) {console.error("getSupportedOutputCapability photoProfilesArray == null || undefined");}//videoProfiles属性为获取当前设备支持的录像输出流。let videoProfilesArray: Array<camera.VideoProfile> = cameraOutputCapability.videoProfiles;if (!videoProfilesArray) {console.error("getSupportedOutputCapability videoProfilesArray == null || undefined");}//supportedMetadataObjectTypes属性为获取当前设备支持的metadata流类型信息集合，目前只定义了FACE_DETECTION用于人脸检测的metadata类型let metadataObjectTypesArray: Array<camera.MetadataObjectType> = cameraOutputCapability.supportedMetadataObjectTypes;if (!metadataObjectTypesArray) {console.error("getSupportedOutputCapability metadataObjectTypesArray== null || undefined");}return cameraOutputCapability;
}
创建相机输出流
根据用户需求创建不同类型的输出流
//创建预览流
function createPreviewOutput(cameraManager: camera.CameraManager, cameraOutputCapability: camera.CameraOutputCapability, surfaceId: string): camera.PreviewOutput | undefined {let previewProfilesArray: Array<camera.Profile> = cameraOutputCapability.previewProfiles;let previewOutput: camera.PreviewOutput | undefined = undefined;try {previewOutput = cameraManager.createPreviewOutput(previewProfilesArray[0], surfaceId);} catch (error) {let err = error as BusinessError;console.error(`The createPreviewOutput call failed. error code: ${err.code}`);}return previewOutput;
}// 创建拍照流
function createPhotoOutput(cameraManager: camera.CameraManager, cameraOutputCapability: camera.CameraOutputCapability): camera.PhotoOutput | undefined {let photoProfilesArray: Array<camera.Profile> = cameraOutputCapability.photoProfiles;let photoOutput: camera.PhotoOutput | undefined = undefined;try {photoOutput = cameraManager.createPhotoOutput(photoProfilesArray[0]);} catch (error) {let err = error as BusinessError;console.error(`The createPhotoOutput call failed. error code: ${err.code}`);}return photoOutput;
}//创建录像流
function createVideoOutput(cameraOutputCapability: camera.CameraOutputCapability, cameraManager: camera.CameraManager, surfaceId: string): camera.VideoOutput | undefined {let videoProfilesArray: Array<camera.VideoProfile> = cameraOutputCapability.videoProfiles;let videoOutput: camera.VideoOutput | undefined = undefined;try {videoOutput = cameraManager.createVideoOutput(videoProfilesArray[0], surfaceId);} catch (error) {let err = error as BusinessError;console.error(`The createVideoOutput call failed. error code: ${err.code}`);}return videoOutput;
}
API参考
createCameraInput
createCameraInput(camera: CameraDevice): CameraInput
使用CameraDevice对象创建CameraInput实例，同步返回结果。
参数CameraDevice对象，通过 CameraManager.getSupportedCameras 接口获取。
createCameraInput(position: CameraPosition, type: CameraType): CameraInput
根据相机位置和类型创建CameraInput实例，同步返回结果。
getSupportedSceneModes
getSupportedSceneModes(camera: CameraDevice): Array<SceneMode>enum SceneMode {NORMAL_PHOTO = 1, // 普通拍照模式NORMAL_VIDEO = 2, // 普通录像模式SECURE_PHOTO = 12, // 安全相机模式... // 其余模式为system api，如人像、夜景、专业拍照模式等
}
getSupportedOutputCapability
getSupportedOutputCapability(camera: CameraDevice, mode: SceneMode): CameraOutputCapabilityinterface CameraOutputCapability {readonly previewProfiles: Array<Profile>;readonly photoProfiles: Array<Profile>;readonly videoProfiles: Array<VideoProfile>;readonly depthProfiles: Array<DepthProfile>; //深度数据配置信息，systemapireadonly supportedMetadataObjectTypes: Array<MetadataObjectType>;}查询相机设备在某种模式下支持的输出能力，同步返回结果
