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wusongqingwusongqingUpdate docs against 108550+104311+107753+106698+107964
6abcb38e创建于 2025年10月10日历史提交

Video Recording Practices (C/C++)

Before developing a camera application, you must request required permissions.

This topic provides sample code that covers the complete video recording process and the API calling sequence. For details about a single process (such as device input, session management, and video recording), see the corresponding C/C++ development guide links provided in Requesting Camera Development Permissions.

Development Process

After obtaining the output stream capabilities supported by the camera, create a video stream. The development process is as follows:

Recording Development Process

Complete Sample Code

  1. Link the dynamic library in the CMake script.

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

  2. Create the header file 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. Import the NDK APIs on the C++ side, and perform video recording based on the surface ID passed in.

    #include "hilog/log.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_INFO(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_INFO(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_INFO(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;
    // Create a CameraManager object.
    Camera_ErrorCode ret = OH_Camera_GetCameraManager(&cameraManager);
    if (cameraManager == nullptr || ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_Camera_GetCameraManager failed.");
        return;
    }
    // Listen for camera status changes.
    ret = OH_CameraManager_RegisterCallback(cameraManager, GetCameraManagerListener());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_RegisterCallback failed.");
        return;
    }

    // Obtain the camera list.
    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_ERROR(LOG_APP, "cameraId  =  %{public}s ", cameras[index].cameraId);              // Obtain the camera ID.
        OH_LOG_ERROR(LOG_APP, "cameraPosition  =  %{public}d ", cameras[index].cameraPosition);  // Obtain the camera position.
        OH_LOG_ERROR(LOG_APP, "cameraType  =  %{public}d ", cameras[index].cameraType);          // Obtain the camera type.
        OH_LOG_ERROR(LOG_APP, "connectionType  =  %{public}d ", cameras[index].connectionType);  // Obtain the camera connection type.
    }

    if (size < cameraDeviceIndex + 1) {
        OH_LOG_ERROR(LOG_APP, "cameraDeviceIndex is invalid.");
        return;
    }

    // Obtain the output stream capability supported by the camera.
    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;
    }
    // Ensure that the aspect ratio of the preview stream is the same as that of the video stream. To record HDR videos, choose Camera_VideoProfile that supports HDR.
    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);
        // The profile of CAMERA_FORMAT_YUV_420_SP is used by default.
        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;
    }
    // Create a VideoOutput instance.
    ret = OH_CameraManager_CreateVideoOutput(cameraManager, videoProfile, videoSurfaceId, &videoOutput);
    if (videoOutput == nullptr || ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateVideoOutput failed.");
        return;
    }

    // Listen for video output errors.
    ret = OH_VideoOutput_RegisterCallback(videoOutput, GetVideoOutputListener());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_RegisterCallback failed.");
    }

    // Create a session.
    ret = OH_CameraManager_CreateCaptureSession(cameraManager, &captureSession);
    if (captureSession == nullptr || ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateCaptureSession failed.");
        return;
    }
    // Listen for session errors.
    ret = OH_CaptureSession_RegisterCallback(captureSession, GetCaptureSessionRegister());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_RegisterCallback failed.");
    }

    // Start configuration for the session.
    ret = OH_CaptureSession_BeginConfig(captureSession);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_BeginConfig failed.");
        return;
    }

    // Create a camera input stream.
    ret = OH_CameraManager_CreateCameraInput(cameraManager, &cameras[cameraDeviceIndex], &cameraInput);
    if (cameraInput == nullptr || ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreateCameraInput failed.");
        return;
    }

    // Listen for camera input errors.
    ret = OH_CameraInput_RegisterCallback(cameraInput, GetCameraInputListener());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraInput_RegisterCallback failed.");
    }

    // Open the camera.
    ret = OH_CameraInput_Open(cameraInput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraInput_Open failed.");
        return;
    }

    // Add the camera input stream to the session.
    ret = OH_CaptureSession_AddInput(captureSession, cameraInput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddInput failed.");
        return;
    }

    // Create a preview output stream. For details about the surfaceId parameter, see the XComponent. The preview stream is the surface provided by the XComponent.
    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;
    }

    // Add the preview output stream to the session.
    ret = OH_CaptureSession_AddPreviewOutput(captureSession, previewOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddPreviewOutput failed.");
        return;
    }

    // Add the video output stream to the session.
    ret = OH_CaptureSession_AddVideoOutput(captureSession, videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_AddVideoOutput failed.");
        return;
    }

    // Commit the session configuration.
    ret = OH_CaptureSession_CommitConfig(captureSession);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_CommitConfig failed.");
        return;
    }

    // Start the session.
    ret = OH_CaptureSession_Start(captureSession);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CaptureSession_Start failed.");
        return;
    }

    // Start the video output stream.
    ret = OH_VideoOutput_Start(videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_Start failed.");
        return;
    }

    // Call avRecorder.start() on the TS side to start video recording.

    // Stop the video output stream.
    ret = OH_VideoOutput_Stop(videoOutput);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_VideoOutput_Stop failed.");
    }

    // Call avRecorder.stop() on the TS side to stop video recording.

    // Stop the session.
    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);
    }

    // Release the camera input stream.
    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);
    }

    // Release the preview output stream.
    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);
    }

    // Release the video output stream.
    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);
    }

    // Release the session.
    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);
    }

    // Release the resources.
    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 success");
    }
    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 success");
    }
}