# 高性能拍照实现方案(仅对系统应用开放)(ArkTS) 在开发相机应用时,需要先参考开发准备[申请相关权限](camera-preparation.md)。 当前示例提供完整的高性能拍照流程介绍,方便开发者了解完整的接口调用顺序。 在参考以下示例前,建议开发者查看[高性能拍照(仅对系统应用开放)(ArkTS)](camera-deferred-photo.md)的具体章节,了解[设备输入](camera-device-input.md)、[会话管理](camera-session-management.md)、[拍照](camera-shooting.md)等单个流程。 ## 开发流程 在获取到相机支持的输出流能力后,开始创建拍照流,开发流程如下。 ![deferred-photo-development-process](figures/deferred-photo-development-process.png) ## 完整示例 Context获取方式请参考:[获取UIAbility的上下文信息](../../application-models/uiability-usage.md#获取uiability的上下文信息)。 ```ts import { camera } from '@kit.CameraKit'; import { image } from '@kit.ImageKit'; import { BusinessError } from '@kit.BasicServicesKit'; import { common } from '@kit.AbilityKit'; import { fileIo as fs } from '@kit.CoreFileKit'; import { photoAccessHelper } from '@kit.MediaLibraryKit'; let context = getContext(this); // 写文件方式落盘真图 async function savePicture(photoObj: camera.Photo): Promise { let accessHelper = photoAccessHelper.getPhotoAccessHelper(context); let testFileName = 'testFile' + Date.now() + '.jpg'; //createAsset的调用需要ohos.permission.READ_IMAGEVIDEO和ohos.permission.WRITE_IMAGEVIDEO的权限 let photoAsset = await accessHelper.createAsset(testFileName); const fd = await photoAsset.open('rw'); let buffer: ArrayBuffer | undefined = undefined; photoObj.main.getComponent(image.ComponentType.JPEG, (errCode: BusinessError, component: image.Component): void => { if (errCode || component === undefined) { console.error('getComponent failed'); return; } if (component.byteBuffer) { buffer = component.byteBuffer; } else { console.error('byteBuffer is null'); return; } }); if (buffer) { await fs.write(fd, buffer); } await photoAsset.close(fd); await photoObj.release(); } // 调用媒体库方式落盘缩略图 async function saveDeferredPhoto(proxyObj: camera.DeferredPhotoProxy): Promise { try { // 创建 photoAsset let accessHelper = photoAccessHelper.getPhotoAccessHelper(context); let testFileName = 'testFile' + Date.now() + '.jpg'; let photoAsset = await accessHelper.createAsset(testFileName); // 将缩略图代理类传递给媒体库 let mediaRequest: photoAccessHelper.MediaAssetChangeRequest = new photoAccessHelper.MediaAssetChangeRequest(photoAsset); mediaRequest.addResource(photoAccessHelper.ResourceType.PHOTO_PROXY, proxyObj); let res = await accessHelper.applyChanges(mediaRequest); console.info('saveDeferredPhoto success.'); } catch (err) { console.error(`Failed to saveDeferredPhoto. error: ${JSON.stringify(err)}`); } } async function deferredPhotoCase(baseContext: common.BaseContext, surfaceId: string): Promise { // 创建CameraManager对象 let cameraManager: camera.CameraManager = camera.getCameraManager(baseContext); if (!cameraManager) { console.error("camera.getCameraManager error"); return; } // 监听相机状态变化 cameraManager.on('cameraStatus', (err: BusinessError, cameraStatusInfo: camera.CameraStatusInfo) => { if (err !== undefined && err.code !== 0) { console.error(`cameraStatus with errorCode: ${err.code}`); return; } console.info(`camera : ${cameraStatusInfo.camera.cameraId}`); console.info(`status: ${cameraStatusInfo.status}`); }); // 获取相机列表 let cameraArray: Array = cameraManager.getSupportedCameras(); if (cameraArray.length <= 0) { console.error("cameraManager.getSupportedCameras error"); return; } for (let index = 0; index < cameraArray.length; index++) { console.info('cameraId : ' + cameraArray[index].cameraId); // 获取相机ID console.info('cameraPosition : ' + cameraArray[index].cameraPosition); // 获取相机位置 console.info('cameraType : ' + cameraArray[index].cameraType); // 获取相机类型 console.info('connectionType : ' + cameraArray[index].connectionType); // 获取相机连接类型 } // 创建相机输入流 let cameraInput: camera.CameraInput | undefined = undefined; try { cameraInput = cameraManager.createCameraInput(cameraArray[0]); } catch (error) { let err = error as BusinessError; console.error('Failed to createCameraInput errorCode = ' + err.code); } if (cameraInput === undefined) { return; } // 监听cameraInput错误信息 let cameraDevice: camera.CameraDevice = cameraArray[0]; cameraInput.on('error', cameraDevice, (error: BusinessError) => { console.error(`Camera input error code: ${error.code}`); }) // 打开相机 await cameraInput.open(); // 获取支持的模式类型 let sceneModes: Array = cameraManager.getSupportedSceneModes(cameraArray[0]); let isSupportPhotoMode: boolean = sceneModes.indexOf(camera.SceneMode.NORMAL_PHOTO) >= 0; if (!isSupportPhotoMode) { console.error('photo mode not support'); return; } // 获取相机设备支持的输出流能力 let cameraOutputCap: camera.CameraOutputCapability = cameraManager.getSupportedOutputCapability(cameraArray[0], camera.SceneMode.NORMAL_PHOTO); if (!cameraOutputCap) { console.error("cameraManager.getSupportedOutputCapability error"); return; } console.info("outputCapability: " + JSON.stringify(cameraOutputCap)); let previewProfilesArray: Array = cameraOutputCap.previewProfiles; if (!previewProfilesArray) { console.error("createOutput previewProfilesArray == null || undefined"); } let photoProfilesArray: Array = cameraOutputCap.photoProfiles; if (!photoProfilesArray) { console.error("createOutput photoProfilesArray == null || undefined"); } // 创建预览输出流,其中参数 surfaceId 参考上文 XComponent 组件,预览流为XComponent组件提供的surface let previewOutput: camera.PreviewOutput | undefined = undefined; try { previewOutput = cameraManager.createPreviewOutput(previewProfilesArray[0], surfaceId); } catch (error) { let err = error as BusinessError; console.error(`Failed to create the PreviewOutput instance. error code: ${err.code}`); } if (previewOutput === undefined) { return; } // 监听预览输出错误信息 previewOutput.on('error', (error: BusinessError) => { console.error(`Preview output error code: ${error.code}`); }); // 创建拍照输出流 let photoOutput: camera.PhotoOutput | undefined = undefined; try { photoOutput = cameraManager.createPhotoOutput(photoProfilesArray[0]); } catch (error) { let err = error as BusinessError; console.error('Failed to createPhotoOutput errorCode = ' + err.code); } if (photoOutput === undefined) { return; } //创建会话 let photoSession: camera.PhotoSession | undefined = undefined; try { photoSession = cameraManager.createSession(camera.SceneMode.NORMAL_PHOTO) as camera.PhotoSession; } catch (error) { let err = error as BusinessError; console.error('Failed to create the photoSession instance. errorCode = ' + err.code); } if (photoSession === undefined) { return; } // 监听session错误信息 photoSession.on('error', (error: BusinessError) => { console.error(`Capture session error code: ${error.code}`); }); // 开始配置会话 try { photoSession.beginConfig(); } catch (error) { let err = error as BusinessError; console.error('Failed to beginConfig. errorCode = ' + err.code); } // 向会话中添加相机输入流 try { photoSession.addInput(cameraInput); } catch (error) { let err = error as BusinessError; console.error('Failed to addInput. errorCode = ' + err.code); } // 向会话中添加预览输出流 try { photoSession.addOutput(previewOutput); } catch (error) { let err = error as BusinessError; console.error('Failed to addOutput(previewOutput). errorCode = ' + err.code); } // 向会话中添加拍照输出流 try { photoSession.addOutput(photoOutput); } catch (error) { let err = error as BusinessError; console.error('Failed to addOutput(photoOutput). errorCode = ' + err.code); } // 注册原图回调监听 photoOutput.on('photoAvailable', (err: BusinessError, photoObj: camera.Photo): void => { if (err) { console.info(`photoAvailable error: ${JSON.stringify(err)}.`); return; } savePicture(photoObj).then(() => { // 落盘完成后,释放photo对象。 photoObj.release(); }); }); // 注册分段式缩略图代理回调监听 photoOutput.on('deferredPhotoProxyAvailable', (err: BusinessError, proxyObj: camera.DeferredPhotoProxy): void => { if (err) { console.info(`deferredPhotoProxyAvailable error: ${JSON.stringify(err)}.`); return; } console.info('photoOutPutCallBack deferredPhotoProxyAvailable'); // 获取缩略图 pixelMap proxyObj.getThumbnail().then((thumbnail: image.PixelMap) => { AppStorage.setOrCreate('proxyThumbnail', thumbnail); }); // 调用媒体库接口落盘缩略图 saveDeferredPhoto(proxyObj).then(() => { // 落盘完成后,释放代理类对象。 proxyObj.release(); }); }); // 判断是否支持分段式拍照能力 let isSupportDeferred: boolean = photoOutput.isDeferredImageDeliverySupported(camera.DeferredDeliveryImageType.PHOTO); console.info('isDeferredImageDeliverySupported res:' + isSupportDeferred); if (isSupportDeferred) { // 使能分段式拍照 photoOutput.deferImageDelivery(camera.DeferredDeliveryImageType.PHOTO); // 查询使能分段式结果 let isSupportEnabled: boolean = photoOutput.isDeferredImageDeliveryEnabled(camera.DeferredDeliveryImageType.PHOTO); console.info('isDeferredImageDeliveryEnabled res:' + isSupportEnabled); } // 提交会话配置 await photoSession.commitConfig(); // 启动会话 await photoSession.start().then(() => { console.info('Promise returned to indicate the session start success.'); }); // 判断设备是否支持闪光灯 let flashStatus: boolean = false; try { flashStatus = photoSession.hasFlash(); } catch (error) { let err = error as BusinessError; console.error('Failed to hasFlash. errorCode = ' + err.code); } console.info('Returned with the flash light support status:' + flashStatus); if (flashStatus) { // 判断是否支持自动闪光灯模式 let flashModeStatus: boolean = false; try { let status: boolean = photoSession.isFlashModeSupported(camera.FlashMode.FLASH_MODE_AUTO); flashModeStatus = status; } catch (error) { let err = error as BusinessError; console.error('Failed to check whether the flash mode is supported. errorCode = ' + err.code); } if(flashModeStatus) { // 设置自动闪光灯模式 try { photoSession.setFlashMode(camera.FlashMode.FLASH_MODE_AUTO); } catch (error) { let err = error as BusinessError; console.error('Failed to set the flash mode. errorCode = ' + err.code); } } } // 判断是否支持连续自动变焦模式 let focusModeStatus: boolean = false; try { let status: boolean = photoSession.isFocusModeSupported(camera.FocusMode.FOCUS_MODE_CONTINUOUS_AUTO); focusModeStatus = status; } catch (error) { let err = error as BusinessError; console.error('Failed to check whether the focus mode is supported. errorCode = ' + err.code); } if (focusModeStatus) { // 设置连续自动变焦模式 try { photoSession.setFocusMode(camera.FocusMode.FOCUS_MODE_CONTINUOUS_AUTO); } catch (error) { let err = error as BusinessError; console.error('Failed to set the focus mode. errorCode = ' + err.code); } } // 获取相机支持的可变焦距比范围 let zoomRatioRange: Array = []; try { zoomRatioRange = photoSession.getZoomRatioRange(); } catch (error) { let err = error as BusinessError; console.error('Failed to get the zoom ratio range. errorCode = ' + err.code); } if (zoomRatioRange.length <= 0) { return; } // 设置可变焦距比 try { photoSession.setZoomRatio(zoomRatioRange[0]); } catch (error) { let err = error as BusinessError; console.error('Failed to set the zoom ratio value. errorCode = ' + err.code); } let photoCaptureSetting: camera.PhotoCaptureSetting = { quality: camera.QualityLevel.QUALITY_LEVEL_HIGH, // 设置图片质量高 rotation: camera.ImageRotation.ROTATION_0 // 设置图片旋转角度0 } // 使用当前拍照设置进行拍照 photoOutput.capture(photoCaptureSetting, (err: BusinessError) => { if (err) { console.error(`Failed to capture the photo ${err.message}`); return; } console.info('Callback invoked to indicate the photo capture request success.'); }); // 需要在拍照结束之后调用以下关闭摄像头和释放会话流程,避免拍照未结束就将会话释放。 // 停止当前会话 await photoSession.stop(); // 释放相机输入流 await cameraInput.close(); // 释放预览输出流 await previewOutput.release(); // 释放拍照输出流 await photoOutput.release(); // 释放会话 await photoSession.release(); // 会话置空 photoSession = undefined; } ```