拍照实践(C/C++)

在开发相机应用时，需要先参考开发准备申请相关权限。

当前示例提供完整的拍照流程及其接口调用顺序的介绍。对于单个流程（如设备输入、会话管理、拍照）的介绍请参考相机开发指导(Native)的具体章节。

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。

完整示例

1. 在CMake脚本中链接相关动态库。 txt target_link_libraries(entry PUBLIC libace_napi.z.so libhilog_ndk.z.so libnative_buffer.so libohcamera.so libohimage.so libohfileuri.so )
2. 创建头文件ndk_camera.h。 “`c++ #include “ohcamera/camera.h” #include “ohcamera/camera_input.h” #include “ohcamera/capture_session.h” #include “ohcamera/photo_output.h” #include “ohcamera/preview_output.h” #include “ohcamera/video_output.h” #include “ohcamera/camera_manager.h”

class NDKCamera { public: ~NDKCamera(); NDKCamera(char* previewId); Camera_ErrorCode RegisterBufferCb(void* cb); }; “`

1. cpp侧导入NDK接口，并根据传入的SurfaceId进行拍照。

   #include "hilog/log.h"
   #include "ndk_camera.h"
   
   
   void CaptureSessionOnFocusStateChange(Camera_CaptureSession* session, Camera_FocusState focusState)
   {
       OH_LOG_INFO(LOG_APP, "CaptureSessionOnFocusStateChange");
   }
   
   
   void CaptureSessionOnError(Camera_CaptureSession* session, Camera_ErrorCode errorCode)
   {
       OH_LOG_INFO(LOG_APP, "CaptureSessionOnError = %{public}d", errorCode);
   }
   
   
   CaptureSession_Callbacks* GetCaptureSessionRegister(void)
   {
       static CaptureSession_Callbacks captureSessionCallbacks = {
           .onFocusStateChange = CaptureSessionOnFocusStateChange,
           .onError = CaptureSessionOnError
       };
       return &captureSessionCallbacks;
   }
   
   
   void PreviewOutputOnFrameStart(Camera_PreviewOutput* previewOutput)
   {
       OH_LOG_INFO(LOG_APP, "PreviewOutputOnFrameStart");
   }
   
   
   void PreviewOutputOnFrameEnd(Camera_PreviewOutput* previewOutput, int32_t frameCount)
   {
       OH_LOG_INFO(LOG_APP, "PreviewOutputOnFrameEnd = %{public}d", frameCount);
   }
   
   
   void PreviewOutputOnError(Camera_PreviewOutput* previewOutput, Camera_ErrorCode errorCode)
   {
       OH_LOG_INFO(LOG_APP, "PreviewOutputOnError = %{public}d", errorCode);
   }
   
   
   PreviewOutput_Callbacks* GetPreviewOutputListener(void)
   {
       static PreviewOutput_Callbacks previewOutputListener = {
           .onFrameStart = PreviewOutputOnFrameStart,
           .onFrameEnd = PreviewOutputOnFrameEnd,
           .onError = PreviewOutputOnError
       };
       return &previewOutputListener;
   }
   
   
   void OnCameraInputError(const Camera_Input* cameraInput, Camera_ErrorCode errorCode)
   {
       OH_LOG_INFO(LOG_APP, "OnCameraInput errorCode = %{public}d", errorCode);
   }
   
   
   CameraInput_Callbacks* GetCameraInputListener(void)
   {
       static CameraInput_Callbacks cameraInputCallbacks = {
           .onError = OnCameraInputError
       };
       return &cameraInputCallbacks;
   }
   
   
   void CameraManagerStatusCallback(Camera_Manager* cameraManager, Camera_StatusInfo* status)
   {
       OH_LOG_INFO(LOG_APP, "CameraManagerStatusCallback is called");
   }
   
   
   CameraManager_Callbacks* GetCameraManagerListener()
   {
       static CameraManager_Callbacks cameraManagerListener = {
           .onCameraStatus = CameraManagerStatusCallback
       };
       return &cameraManagerListener;
   }
   
   
   static void* bufferCb = nullptr;
   Camera_ErrorCode NDKCamera::RegisterBufferCb(void* cb) {
       OH_LOG_INFO(LOG_APP, " RegisterBufferCb start");
       if (cb == nullptr) {
           OH_LOG_INFO(LOG_APP, " RegisterBufferCb invalid error");
           return CAMERA_INVALID_ARGUMENT;
       }
       bufferCb = cb;
   
   
       return CAMERA_OK;
   }
   void OnPhotoAvailable(Camera_PhotoOutput* photoOutput, OH_PhotoNative* photo) {
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable start!");
       OH_ImageNative* imageNative;
       Camera_ErrorCode errCode = OH_PhotoNative_GetMainImage(photo, &imageNative);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable errCode:%{public}d imageNative:%{public}p", errCode, imageNative);
       // 读取 OH_ImageNative 的 size 属性。
       Image_Size size;
       Image_ErrorCode imageErr = OH_ImageNative_GetImageSize(imageNative, &size);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable imageErr:%{public}d width:%{public}d height:%{public}d", imageErr,
           size.width, size.height);
       // 读取 OH_ImageNative 的组件列表的元素个数。
       size_t componentTypeSize = 0;
       imageErr = OH_ImageNative_GetComponentTypes(imageNative, nullptr, &componentTypeSize);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable imageErr:%{public}d componentTypeSize:%{public}zu", imageErr,
           componentTypeSize);
       // 读取 OH_ImageNative 的组件列表。
       uint32_t* components = new uint32_t[componentTypeSize];
       imageErr = OH_ImageNative_GetComponentTypes(imageNative, &components, &componentTypeSize);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable OH_ImageNative_GetComponentTypes imageErr:%{public}d", imageErr);
       // 读取 OH_ImageNative 的第一个组件所对应的缓冲区对象。
       OH_NativeBuffer* nativeBuffer = nullptr;
       imageErr = OH_ImageNative_GetByteBuffer(imageNative, components[0], &nativeBuffer);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable OH_ImageNative_GetByteBuffer imageErr:%{public}d", imageErr);
       // 读取 OH_ImageNative 的第一个组件所对应的缓冲区大小。
       size_t nativeBufferSize = 0;
       imageErr = OH_ImageNative_GetBufferSize(imageNative, components[0], &nativeBufferSize);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable imageErr:%{public}d nativeBufferSize:%{public}zu", imageErr,
            nativeBufferSize);
       // 读取 OH_ImageNative 的第一个组件所对应的像素行宽。
       int32_t rowStride = 0;
       imageErr = OH_ImageNative_GetRowStride(imageNative, components[0], &rowStride);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable imageErr:%{public}d rowStride:%{public}d", imageErr, rowStride);
       // 读取 OH_ImageNative 的第一个组件所对应的像素大小。
       int32_t pixelStride = 0;
       imageErr = OH_ImageNative_GetPixelStride(imageNative, components[0], &pixelStride);
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable imageErr:%{public}d pixelStride:%{public}d", imageErr, pixelStride);
       // 将ION内存映射到进程空间。
       void* virAddr = nullptr; // 指向映射内存的虚拟地址，解除映射后这个指针将不再有效。
       int32_t ret = OH_NativeBuffer_Map(nativeBuffer, &virAddr); // 映射后通过第二个参数virAddr返回内存的首地址。
       OH_LOG_INFO(LOG_APP, "OnPhotoAvailable OH_NativeBuffer_Map err:%{public}d", ret);
       // 通过回调函数，将处理完的buffer传给ArkTS侧做显示或通过安全控件写文件保存，参考拍照(C/C++)开发指导。
       auto cb = (void (*)(void *, size_t))(bufferCb);
       cb(virAddr, nativeBufferSize);
       // 在处理完之后，解除映射并释放缓冲区。
       ret = OH_NativeBuffer_Unmap(nativeBuffer);
       if (ret != 0) {
           OH_LOG_ERROR(LOG_APP, "OnPhotoAvailable OH_NativeBuffer_Unmap error:%{public}d", ret);
       }
   }
   
   
   NDKCamera::NDKCamera(char* previewId)
   {
       Camera_Manager* cameraManager = nullptr;
       Camera_Device* cameras = nullptr;
       Camera_CaptureSession* captureSession = nullptr;
       Camera_OutputCapability* cameraOutputCapability = nullptr;
       const Camera_Profile* previewProfile = nullptr;
       const Camera_Profile* photoProfile = nullptr;
       Camera_PreviewOutput* previewOutput = nullptr;
       Camera_PhotoOutput* photoOutput = nullptr;
       Camera_Input* cameraInput = nullptr;
       uint32_t size = 0;
       uint32_t cameraDeviceIndex = 0;
       char* previewSurfaceId = previewId;
       // 创建CameraManager对象。
       Camera_ErrorCode ret = OH_Camera_GetCameraManager(&cameraManager);
       if (cameraManager == nullptr||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_Camera_GetCameraMananger failed.");
           return;
       }
       // 监听相机状态变化。
       ret = OH_CameraManager_RegisterCallback(cameraManager, GetCameraManagerListener());
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_RegisterCallback failed.");
       }
   
   
       // 获取相机列表。
       ret = OH_CameraManager_GetSupportedCameras(cameraManager, &cameras, &size);
       if (cameras == nullptr||size < 0||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_GetSupportedCameras failed.");
           return;
       }
   
   
       // 创建相机输入流。
       ret = OH_CameraManager_CreateCameraInput(cameraManager, &cameras[cameraDeviceIndex], &cameraInput);
       if (cameraInput == nullptr||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateCameraInput failed.");
           return;
       }
   
   
       // 监听cameraInput错误信息。
       ret = OH_CameraInput_RegisterCallback(cameraInput, GetCameraInputListener());
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraInput_RegisterCallback failed.");
           return;
       }
   
   
       // 打开相机。
       ret = OH_CameraInput_Open(cameraInput);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraInput_Open failed.");
           return;
       }
   
   
       // 获取相机设备支持的输出流能力。
       ret = OH_CameraManager_GetSupportedCameraOutputCapability(cameraManager, &cameras[cameraDeviceIndex],
                                                                 &cameraOutputCapability);
       if (cameraOutputCapability == nullptr||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_GetSupportedCameraOutputCapability failed.");
           return;
       }
   
   
       if (cameraOutputCapability->previewProfiles == nullptr) {
           OH_LOG_ERROR(LOG_APP, "previewProfiles == null");
           return;
       }
       // 根据所需从cameraOutputCapability->previewProfiles中选择合适的预览分辨率
       previewProfile = cameraOutputCapability->previewProfiles[0];
   
   
       if (cameraOutputCapability->photoProfiles == nullptr) {
           OH_LOG_ERROR(LOG_APP, "photoProfiles == null");
           return;
       }
       // 根据所需从cameraOutputCapability->photoProfiles中选择合适的拍照分辨率
       photoProfile = cameraOutputCapability->photoProfiles[0];
   
   
       // 创建预览输出流,其中参数 previewSurfaceId 参考上文 XComponent 组件，预览流为XComponent组件提供的surface。
       ret = OH_CameraManager_CreatePreviewOutput(cameraManager, previewProfile, previewSurfaceId, &previewOutput);
       if (previewProfile == nullptr||previewOutput == nullptr||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreatePreviewOutput failed.");
           return;
       }
   
   
       // 监听预览输出错误信息。
       ret = OH_PreviewOutput_RegisterCallback(previewOutput, GetPreviewOutputListener());
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_PreviewOutput_RegisterCallback failed.");
       }
   
   
       // 创建拍照输出流。
       ret = OH_CameraManager_CreatePhotoOutputWithoutSurface(cameraManager, photoProfile, &photoOutput);
   
   
       // 监听单端式拍照回调。
       ret = OH_PhotoOutput_RegisterPhotoAvailableCallback(photoOutput, OnPhotoAvailable);
   
   
       //创建会话。
       ret = OH_CameraManager_CreateCaptureSession(cameraManager, &captureSession);
       if (captureSession == nullptr||ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateCaptureSession failed.");
           return;
       }
   
   
       // 监听session错误信息。
       ret = OH_CaptureSession_RegisterCallback(captureSession, GetCaptureSessionRegister());
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_RegisterCallback failed.");
       }
   
   
       // 开始配置会话。
       ret = OH_CaptureSession_BeginConfig(captureSession);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_BeginConfig failed.");
           return;
       }
   
   
       // 向会话中添加相机输入流。
       ret = OH_CaptureSession_AddInput(captureSession, cameraInput);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddInput failed.");
           return;
       }
   
   
       // 向会话中添加预览输出流。
       ret = OH_CaptureSession_AddPreviewOutput(captureSession, previewOutput);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddPreviewOutput failed.");
           return;
       }
   
   
       // 向会话中添加拍照输出流。
       ret = OH_CaptureSession_AddPhotoOutput(captureSession, photoOutput);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddPhotoOutput failed.");
           return;
       }
   
   
       // 提交会话配置。
       ret = OH_CaptureSession_CommitConfig(captureSession);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_CommitConfig failed.");
           return;
       }
   
   
       // 启动会话。
       ret = OH_CaptureSession_Start(captureSession);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_Start failed.");
           return;
       }
   
   
       // 判断设备是否支持闪光灯。
       Camera_FlashMode flashMode = FLASH_MODE_AUTO;
       bool hasFlash = false;
       ret = OH_CaptureSession_HasFlash(captureSession, &hasFlash);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_HasFlash failed.");
       }
       if (hasFlash) {
           OH_LOG_INFO(LOG_APP, "hasFlash success");
       } else {
           OH_LOG_ERROR(LOG_APP, "hasFlash fail");
       }
   
   
       // 检测闪光灯模式是否支持。
       bool isSupported = false;
       ret = OH_CaptureSession_IsFlashModeSupported(captureSession, flashMode, &isSupported);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_IsFlashModeSupported failed.");
       }
       if (isSupported) {
           OH_LOG_INFO(LOG_APP, "isFlashModeSupported success");
   
   
           // 设置闪光灯模式。
           ret = OH_CaptureSession_SetFlashMode(captureSession, flashMode);
           if (ret == CAMERA_OK) {
               OH_LOG_INFO(LOG_APP, "OH_CaptureSession_SetFlashMode success.");
           } else {
               OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_SetFlashMode failed. %{public}d ", ret);
           }
   
   
           // 获取当前设备的闪光灯模式。
           ret = OH_CaptureSession_GetFlashMode(captureSession, &flashMode);
           if (ret == CAMERA_OK) {
               OH_LOG_INFO(LOG_APP, "OH_CaptureSession_GetFlashMode success. flashMode：%{public}d ", flashMode);
           } else {
               OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_GetFlashMode failed. %d ", ret);
           }
       } else {
           OH_LOG_ERROR(LOG_APP, "isFlashModeSupported fail");
       }
   
   
       // 判断是否支持连续自动变焦模式。
       Camera_FocusMode focusMode = FOCUS_MODE_CONTINUOUS_AUTO;
       bool isFocusModeSupported = false;
       ret = OH_CaptureSession_IsFocusModeSupported(captureSession, focusMode, &isFocusModeSupported);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_IsFocusModeSupported failed.");
       }
       if (isFocusModeSupported) {
           OH_LOG_INFO(LOG_APP, "isFocusModeSupported success");
           ret = OH_CaptureSession_SetFocusMode(captureSession, focusMode);
           if (ret != CAMERA_OK) {
               OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_SetFocusMode failed. %{public}d ", ret);
           }
           ret = OH_CaptureSession_GetFocusMode(captureSession, &focusMode);
           if (ret == CAMERA_OK) {
               OH_LOG_INFO(LOG_APP, "OH_CaptureSession_GetFocusMode success. focusMode%{public}d ", focusMode);
           } else {
               OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_GetFocusMode failed. %d ", ret);
           }
       } else {
           OH_LOG_ERROR(LOG_APP, "isFocusModeSupported fail");
       }
   
   
       // 获取相机支持的可变焦距比范围。
       float minZoom;
       float maxZoom;
       ret = OH_CaptureSession_GetZoomRatioRange(captureSession, &minZoom, &maxZoom);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_GetZoomRatioRange failed.");
       } else {
           OH_LOG_INFO(LOG_APP, "OH_CaptureSession_GetZoomRatioRange success. minZoom: %{public}f, maxZoom:%{public}f",
               minZoom, maxZoom);
       }
   
   
       // 设置变焦。
       ret = OH_CaptureSession_SetZoomRatio(captureSession, maxZoom);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_CaptureSession_SetZoomRatio success.");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_SetZoomRatio failed. %{public}d ", ret);
       }
   
   
       // 获取当前设备的变焦值。
       ret = OH_CaptureSession_GetZoomRatio(captureSession, &maxZoom);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_CaptureSession_GetZoomRatio success. zoom：%{public}f ", maxZoom);
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_GetZoomRatio failed. %{public}d ", ret);
       }
   
   
       // 无拍照设置进行拍照。
       ret = OH_PhotoOutput_Capture(photoOutput);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_PhotoOutput_Capture success ");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_PhotoOutput_Capture failed. %d ", ret);
       }
   
   
       // 停止当前会话。
       ret = OH_CaptureSession_Stop(captureSession);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_CaptureSession_Stop success ");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_Stop failed. %d ", ret);
       }
   
   
       // 释放相机输入流。
       ret = OH_CameraInput_Close(cameraInput);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_CameraInput_Close success ");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CameraInput_Close failed. %d ", ret);
       }
   
   
       // 释放预览输出流。
       ret = OH_PreviewOutput_Release(previewOutput);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_PreviewOutput_Release success ");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_PreviewOutput_Release failed. %d ", ret);
       }
   
   
       // 释放拍照输出流。
       ret = OH_PhotoOutput_Release(photoOutput);
       if (ret == CAMERA_OK) {
         OH_LOG_INFO(LOG_APP, "OH_PhotoOutput_Release success ");
       } else {
         OH_LOG_ERROR(LOG_APP, "OH_PhotoOutput_Release failed. %d ", ret);
       }
   
   
       // 释放会话。
       ret = OH_CaptureSession_Release(captureSession);
       if (ret == CAMERA_OK) {
           OH_LOG_INFO(LOG_APP, "OH_CaptureSession_Release success ");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_Release failed. %d ", ret);
       }
   
   
       // 资源释放。
       ret = OH_CameraManager_DeleteSupportedCameras(cameraManager, cameras, size);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "Delete Cameras failed.");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_DeleteSupportedCameras. ok");
       }
       ret = OH_CameraManager_DeleteSupportedCameraOutputCapability(cameraManager, cameraOutputCapability);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "Delete Cameras failed.");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_CameraManager_DeleteSupportedCameraOutputCapability. ok");
       }
       ret = OH_Camera_DeleteCameraManager(cameraManager);
       if (ret != CAMERA_OK) {
           OH_LOG_ERROR(LOG_APP, "Delete Cameras failed.");
       } else {
           OH_LOG_ERROR(LOG_APP, "OH_Camera_DeleteCameraManager. ok");
       }
   }
   

你可能感兴趣的鸿蒙文章

harmony 鸿蒙Camera Kit（相机服务）

harmony 鸿蒙相机基础动效(ArkTS)

harmony 鸿蒙相机启动恢复实践(ArkTS)

harmony 鸿蒙分段式拍照实践(ArkTS)

harmony 鸿蒙分段式拍照(ArkTS)

harmony 鸿蒙高性能拍照实践(仅对系统应用开放)(ArkTS)

harmony 鸿蒙高性能拍照(仅对系统应用开放)(ArkTS)

harmony 鸿蒙深度信息(仅对系统应用开放)(ArkTS)

harmony 鸿蒙设备输入(ArkTS)

harmony 鸿蒙相机管理(ArkTS)