目录

录像实践(C/C++)

在开发相机应用时，需要先申请相关权限。

当前示例提供完整的录像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、录像）的介绍请参考具体章节。

开发流程

在获取到相机支持的输出流能力后，开始创建录像流，开发流程如下。

完整示例

  1. 在CMake脚本中链接相关动态库。

    target_link_libraries(entry PUBLIC
    libace_napi.z.so
    libohcamera.so
    libhilog_ndk.z.so
)

  2. 创建头文件ndk_camera.h。

    #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, char* videoId);
};

  3. cpp侧导入NDK接口，并根据传入的SurfaceId进行录像。

    #include "hilog/log.h"
#include "ndk_camera.h"
#include <cmath>

bool IsAspectRatioEqual(float videoAspectRatio, float previewAspectRatio)
{
    float epsilon = 1e-6f;
    return fabsf(videoAspectRatio - previewAspectRatio) <= epsilon;
}

void OnCameraInputError(const Camera_Input* cameraInput, Camera_ErrorCode errorCode)
{
    OH_LOG_ERROR(LOG_APP, "OnCameraInput errorCode = %{public}d", errorCode);
}

CameraInput_Callbacks* GetCameraInputListener(void)
{
    static CameraInput_Callbacks cameraInputCallbacks = {
        .onError = OnCameraInputError
    };
    return &cameraInputCallbacks;
}

void CaptureSessionOnFocusStateChange(Camera_CaptureSession* session, Camera_FocusState focusState)
{
    OH_LOG_INFO(LOG_APP, "CaptureSessionOnFocusStateChange");
}

void CaptureSessionOnError(Camera_CaptureSession* session, Camera_ErrorCode errorCode)
{
    OH_LOG_ERROR(LOG_APP, "CaptureSessionOnError = %{public}d", errorCode);
}

CaptureSession_Callbacks* GetCaptureSessionRegister(void)
{
    static CaptureSession_Callbacks captureSessionCallbacks = {
        .onFocusStateChange = CaptureSessionOnFocusStateChange,
        .onError = CaptureSessionOnError
    };
    return &captureSessionCallbacks;
}

void VideoOutputOnFrameStart(Camera_VideoOutput* videoOutput)
{
    OH_LOG_INFO(LOG_APP, "VideoOutputOnFrameStart");
}

void VideoOutputOnFrameEnd(Camera_VideoOutput* videoOutput, int32_t frameCount)
{
    OH_LOG_INFO(LOG_APP, "VideoOutput frameCount = %{public}d", frameCount);
}

void VideoOutputOnError(Camera_VideoOutput* videoOutput, Camera_ErrorCode errorCode)
{
    OH_LOG_ERROR(LOG_APP, "VideoOutput errorCode = %{public}d", errorCode);
}

VideoOutput_Callbacks* GetVideoOutputListener(void)
{
    static VideoOutput_Callbacks videoOutputListener = {
        .onFrameStart = VideoOutputOnFrameStart,
        .onFrameEnd = VideoOutputOnFrameEnd,
        .onError = VideoOutputOnError
    };
    return &videoOutputListener;
}

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;
}

NDKCamera::NDKCamera(char* previewId, char* videoId)
{
    Camera_Manager* cameraManager = nullptr;
    Camera_Device* cameras = nullptr;
    Camera_CaptureSession* captureSession = nullptr;
    Camera_OutputCapability* cameraOutputCapability = nullptr;
    Camera_VideoOutput* videoOutput = nullptr;
    const Camera_Profile* previewProfile = nullptr;
    const Camera_Profile* photoProfile = nullptr;
    const Camera_VideoProfile* videoProfile = nullptr;
    Camera_PreviewOutput* previewOutput = nullptr;
    Camera_PhotoOutput* photoOutput = nullptr;
    Camera_Input* cameraInput = nullptr;
    uint32_t size = 0;
    uint32_t cameraDeviceIndex = 0;
    char* videoSurfaceId = videoId;
    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_GetCameraManager 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.");
        return;
    }

    // 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;
    }

    for (int index = 0; index < size; index++) {
        OH_LOG_INFO(LOG_APP, "cameraId  =  %{public}s ", cameras[index].cameraId);              // 获取相机ID。
        OH_LOG_INFO(LOG_APP, "cameraPosition  =  %{public}d ", cameras[index].cameraPosition);  // 获取相机位置。
        OH_LOG_INFO(LOG_APP, "cameraType  =  %{public}d ", cameras[index].cameraType);          // 获取相机类型。
        OH_LOG_INFO(LOG_APP, "connectionType  =  %{public}d ", cameras[index].connectionType);  // 获取相机连接类型。
    }

    if (size < cameraDeviceIndex + 1) {
        OH_LOG_ERROR(LOG_APP, "cameraDeviceIndex is invalid.");
        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;
    }
    previewProfile = cameraOutputCapability->previewProfiles[0];
    OH_LOG_INFO(LOG_APP, "previewProfile width: %{public}d, height: %{public}d.", previewProfile->size.width,
        previewProfile->size.height);
    if (cameraOutputCapability->photoProfiles == nullptr) {
        OH_LOG_ERROR(LOG_APP, "photoProfiles == null");
        return;
    }
    photoProfile = cameraOutputCapability->photoProfiles[0];

    if (cameraOutputCapability->videoProfiles == nullptr) {
        OH_LOG_ERROR(LOG_APP, "videoProfiles == null");
        return;
    }
    // 预览流宽高比要与录像流的宽高比一致，如果录制的是hdr视频，请筛选支持hdr的Camera_VideoProfile。
    Camera_VideoProfile** videoProfiles = cameraOutputCapability->videoProfiles;
    for (int index = 0; index < cameraOutputCapability->videoProfilesSize; index++) {
        bool isEqual = IsAspectRatioEqual((float)videoProfiles[index]->size.width / videoProfiles[index]->size.height,
            (float)previewProfile->size.width / previewProfile->size.height);
        // 默认筛选CAMERA_FORMAT_YUV_420_SP的profile。
        if (isEqual && videoProfiles[index]->format == Camera_Format::CAMERA_FORMAT_YUV_420_SP) {
            videoProfile = videoProfiles[index];
            OH_LOG_INFO(LOG_APP, "videoProfile width: %{public}d, height: %{public}d.", videoProfile->size.width,
                videoProfile->size.height);
            break;
        }
    }
    if (videoProfile == nullptr) {
        OH_LOG_ERROR(LOG_APP, "Get videoProfile failed.");
        return;
    }
    // 创建VideoOutput对象。
    ret = OH_CameraManager_CreateVideoOutput(cameraManager, videoProfile, videoSurfaceId, &videoOutput);
    if (videoOutput == nullptr || ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateVideoOutput failed.");
        return;
    }

    // 监听视频输出错误信息。
    ret = OH_VideoOutput_RegisterCallback(videoOutput, GetVideoOutputListener());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_RegisterCallback failed.");
    }

    // 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;
    }

    // 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.");
    }

    // 打开相机。
    ret = OH_CameraInput_Open(cameraInput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraInput_Open 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;
    }

    // 创建预览输出流，其中参数 surfaceId 参考下面 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;
    }

    // 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;
    }

    // 向会话中添加录像输出流。
    ret = OH_CaptureSession_AddVideoOutput(captureSession, videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddVideoOutput 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;
    }

    // 启动录像输出流。
    ret = OH_VideoOutput_Start(videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_Start failed.");
        return;
    }

    // 开始录像 ts侧调用avRecorder.start()。

    // 停止录像输出流。
    ret = OH_VideoOutput_Stop(videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_Stop failed.");
    }

    // 停止录像 ts侧调用avRecorder.stop()。

    // 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);
    }

    // 释放录像输出流。
    ret = OH_VideoOutput_Release(videoOutput);
    if (ret == CAMERA_OK) {
        OH_LOG_INFO(LOG_APP, "OH_VideoOutput_Release success ");
    } else {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_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_INFO(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_INFO(LOG_APP, "OH_CameraManager_DeleteSupportedCameraOutputCapability success");
    }
    ret = OH_Camera_DeleteCameraManager(cameraManager);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "Delete Cameras failed.");
    } else {
        OH_LOG_INFO(LOG_APP, "OH_Camera_DeleteCameraManager success");
    }
}

示例代码