openharmony 鸿蒙 native-camera-yuv-shooting

2026-08-25 浏览 (1)

YUV拍照(C/C++)

从API version 23开始，相机框架提供YUV格式图片拍照能力。与普通拍照相比，YUV拍照获取到的是未经过编码的图像数据，完整保留了传感器捕获的原始亮度和色度信息，适用于视频编码或专业处理。同时，拍摄过程会产生更高的能耗开销，保存会占用更多的存储空间。

开发步骤

详细的相机功能API说明请参考Camera模块描述OH_Camera。

  1. 导入NDK接口，接口中提供了相机相关的属性和方法，导入方法如下。

    // 导入NDK接口头文件。
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <string.h>
#include <new>
#include "hilog/log.h"
#include "multimedia/image_framework/image/image_source_native.h"
#include "multimedia/image_framework/image/image_packer_native.h"
#include "multimedia/media_library/media_access_helper_capi.h"
#include "multimedia/media_library/media_asset_base_capi.h"
#include "multimedia/media_library/media_asset_capi.h"
#include "multimedia/media_library/media_asset_change_request_capi.h"
#include "multimedia/media_library/media_asset_manager_capi.h"
#include "ohcamera/camera.h"
#include "ohcamera/camera_input.h"
#include "ohcamera/camera_manager.h"
#include "ohcamera/capture_session.h"
#include "ohcamera/photo_native.h"
#include "ohcamera/photo_output.h"
#include "ohcamera/preview_output.h"
#include "ohcamera/video_output.h"

  2. 在CMake脚本中链接相关动态库。

    target_link_libraries(entry PUBLIC
    libace_napi.z.so
    libhilog_ndk.z.so
    libnative_buffer.so
    libohcamera.so
    libohimage.so
    libohfileuri.so
    libmedia_asset_manager.so
    libimage_source.so
    libpixelmap.so
    libimage_packer.so
    libpicture.so
)

  3. 创建并打开相机设备，参考设备输入(C/C++)中的步骤3-4。

  4. 获取相机设备完整输出能力。

    通过OH_CameraManager_GetSupportedFullCameraOutputCapabilityWithSceneMode()方法，获取当前设备支持的所有输出流的能力，包含预览流、拍照流、录像流等。输出流在CameraOutputCapability中的各个profile字段中，其中拍照流支持YUV格式。根据相机设备指定模式Camera_SceneMode的不同，需要添加不同类型的输出流。

    Camera_OutputCapability* GetSupportedFullCameraOutputCapability(Camera_Manager* cameraManager, Camera_Device &camera)
{
     Camera_OutputCapability* cameraOutputCapability = nullptr;
     // 获取相机设备支持的输出流能力。
     const Camera_Profile* previewProfile = nullptr;
     const Camera_Profile* photoProfile = nullptr;
     Camera_ErrorCode ret = OH_CameraManager_GetSupportedFullCameraOutputCapabilityWithSceneMode(cameraManager, &camera,
         Camera_SceneMode::NORMAL_PHOTO, &cameraOutputCapability);
     if (cameraOutputCapability == nullptr||ret != CAMERA_OK) {
         OH_LOG_ERROR(LOG_APP, "OH_CameraManager_GetSupportedCameraOutputCapability failed.");
         return nullptr;
     }
     return cameraOutputCapability;
}

  5. 选择设备支持的输出流能力，创建拍照输出流。

    通过OH_CameraManager_CreatePhotoOutputWithoutSurface()方法创建拍照输出流。

    可以通过OH_CameraManager_GetSupportedFullCameraOutputCapabilityWithSceneMode()获取相机在指定模式下支持的完整输出能力cameraOutputCapability，参考步骤2。在cameraOutputCapability的photoProfiles中选择支持YUV格式的profile，作为创建拍照输出流的参数photoProfile。

    Camera_PhotoOutput* CreatePhotoOutput(Camera_Manager* cameraManager, const Camera_Profile* photoProfile)
{
    Camera_PhotoOutput* photoOutput = nullptr;
    // 无需传入surfaceId，直接创建拍照流。
    Camera_ErrorCode ret = OH_CameraManager_CreatePhotoOutputWithoutSurface(cameraManager, photoProfile, &photoOutput);
    if (photoOutput == nullptr||ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_CameraManager_CreatePhotoOutputWithoutSurface failed.");
    }
    return photoOutput;
}

  6. 注册单段式(PhotoAvailable)或分段式(PhotoAssetAvailable)拍照回调，若应用希望快速得到回图，推荐使用分段式拍照(PhotoAssetAvailable)回调。

    注意：

    如果已经注册了PhotoAssetAvailable回调，并且在Session开始之后又注册了PhotoAvailable回调，PhotoAssetAvailable和PhotoAvailable同时注册会导致流被重启，仅PhotoAssetAvailable生效。

    • 单段式拍照（PhotoAvailable）开发流程：

      • 在会话OH_CaptureSession_CommitConfig前注册单段式拍照回调。
      • 在单段式拍照回调函数中获取图片信息，解析出pixelMap数据，做自定义业务处理。
      • 将处理完的pixelMap通过回调传给ArkTS侧，做图片显示或通过安全控件写文件保存图片。
      • 使用完后解注册单段式拍照回调函数。
      // 单段式拍照回调函数。
void OnPhotoAvailable(Camera_PhotoOutput* photoOutput, OH_PhotoNative* photo)
{
    OH_LOG_INFO(LOG_APP, "OnPhotoAvailable start!");
    OH_PictureNative* picture;
    Camera_ErrorCode errCode = OH_PhotoNative_GetUncompressedImage(photo, &picture);
    if (errCode != CAMERA_OK||picture == nullptr) {
        OH_LOG_ERROR(LOG_APP, "OH_PhotoNative_GetUncompressedImage call failed, errorCode: %{public}d", errCode);
        return;
    }
    OH_LOG_INFO(LOG_APP, "OnPhotoAvailable errCode:%{public}d picture:%{public}p", errCode, picture);
    // 读取OH_PictureNative中的主图mainPixelMap。
    OH_PixelmapNative* mainPixelmap;
    Image_ErrorCode imageErr = OH_PictureNative_GetMainPixelmap(picture, &mainPixelmap);
    if (imageErr != IMAGE_SUCCESS||mainPixelmap == nullptr) {
        OH_LOG_ERROR(LOG_APP, "OH_ImageNative_GetImageSize call failed, errorCode: %{public}d", imageErr);
        return;
    }
    OH_LOG_INFO(LOG_APP, "OH_PictureNative_GetMainPixelmap success");
    // 获取主图Pixelmap中所有像素所占用的总字节数。
    uint32_t byteCount = 0;
    imageErr = OH_PixelmapNative_GetByteCount(mainPixelmap, &byteCount);
    OH_LOG_INFO(LOG_APP, "OH_PixelmapNative_GetByteCount count:%{public}u", byteCount);
    // 获取主图的图像像素信息。
    OH_Pixelmap_ImageInfo* imageInfo;
    imageErr = OH_PixelmapNative_GetImageInfo(mainPixelmap, imageInfo);
    OH_LOG_INFO(LOG_APP, "OH_PixelmapNative_GetImageInfo errorCode:%{public}d", imageErr);

    uint32_t width = 0;
    uint32_t height = 0;
    uint32_t rowStride = 0;
    int32_t pixelFormat = PIXEL_FORMAT::PIXEL_FORMAT_UNKNOWN;
    int32_t alphaMode = PIXELMAP_ALPHA_TYPE::PIXELMAP_ALPHA_TYPE_UNKNOWN;
    int32_t alphaType = PIXELMAP_ALPHA_TYPE::PIXELMAP_ALPHA_TYPE_UNKNOWN;
    // 获取主图图像像素信息中的宽度。
    OH_PixelmapImageInfo_GetWidth(imageInfo, &width);
    // 获取主图图像像素信息中的高度。
    OH_PixelmapImageInfo_GetHeight(imageInfo, &height);
    // 获取主图图像像素信息中的行跨距。
    OH_PixelmapImageInfo_GetRowStride(imageInfo, &rowStride);
    // 获取主图图像像素信息中的像素格式。
    OH_PixelmapImageInfo_GetPixelFormat(imageInfo, &pixelFormat);
    // 获取主图图像像素信息中的透明通道类型。
    OH_PixelmapImageInfo_GetAlphaMode(imageInfo, &alphaMode);
    // 获取主图图像像素信息中的默认的透明通道类型。
    OH_PixelmapImageInfo_GetAlphaType(imageInfo, &alphaType);
    OH_LOG_INFO(LOG_APP, "OH_PixelmapNative_GetImageInfo width:%{public}u height:%{public}u rowStride:%{public}u pixelFormat:%{public}d alphaMode:%{public}d alphaType:%{public}d", width, height, rowStride, pixelFormat, alphaMode, alphaType);
   // 释放资源。
    OH_PixelmapNative_Release(mainPixelmap);
    OH_PictureNative_Release(picture);
}

// 注册单段式拍照回调。
Camera_ErrorCode PhotoOutputRegisterPhotoAvailableCallback(Camera_PhotoOutput* photoOutput)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutputRegisterPhotoAvailableCallback start!");
    Camera_ErrorCode ret = OH_PhotoOutput_RegisterPhotoAvailableCallback(photoOutput, OnPhotoAvailable);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "PhotoOutputRegisterPhotoAvailableCallback failed.");
    }
    OH_LOG_INFO(LOG_APP, "PhotoOutputRegisterPhotoAvailableCallback return with ret code: %{public}d!", ret);
    return ret;
}

// 解注册单段式拍照回调。
Camera_ErrorCode PhotoOutputUnRegisterPhotoAvailableCallback(Camera_PhotoOutput* photoOutput)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutputUnRegisterPhotoAvailableCallback start!");
    Camera_ErrorCode ret = OH_PhotoOutput_UnregisterPhotoAvailableCallback(photoOutput, OnPhotoAvailable);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "PhotoOutputUnRegisterPhotoAvailableCallback failed.");
    }
    OH_LOG_INFO(LOG_APP, "PhotoOutputUnRegisterPhotoAvailableCallback return with ret code: %{public}d!", ret);
    return ret;
}

    • 分段式拍照（PhotoAvailable）开发流程：

      // 声明快速返图回调。
void OnRequestQuickImageDataPreparedWithDetails(MediaLibrary_ErrorCode result, MediaLibrary_RequestId requestId, MediaLibrary_MediaQuality mediaQuality, MediaLibrary_MediaContentType type, OH_ImageSourceNative* imageSourceNative, OH_PictureNative* pictureNative)
{
    OH_LOG_INFO(LOG_APP, "OnRequestQuickImageDataPreparedWithDetails start!");
    if (!pictureNative && !imageSourceNative) {
        OH_LOG_ERROR(LOG_APP, "OnRequestQuickImageDataPreparedWithDetails, pictureNative and imageSourceNative are null.");
        return;
    } else if (!pictureNative && imageSourceNative) {
        OH_LOG_ERROR(LOG_APP, "OnRequestQuickImageDataPreparedWithDetails, pictureNative is null.");
    } else if (pictureNative && !imageSourceNative) {
        OH_LOG_ERROR(LOG_APP, "OnRequestQuickImageDataPreparedWithDetails, imageSourceNative is null.");
    } else {
        OH_LOG_INFO(LOG_APP, "OnRequestQuickImageDataPreparedWithDetails, pictureNative and imageSourceNative are not null.");
    }
}

// 分段式拍照回调函数。
void OnPhotoAssetAvailable(Camera_PhotoOutput* photoOutput, OH_MediaAsset* mediaAsset)
{
    OH_LOG_INFO(LOG_APP, "OnPhotoAssetAvailable start!");
    if (mediaAsset == nullptr) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable invalid error, mediaAsset is null.");
        return;
    }
    // 尝试获取mediaAsset中的uri信息。
    const char* uri = nullptr;
    MediaLibrary_ErrorCode result = OH_MediaAsset_GetUri(mediaAsset, &uri);
    if (uri == nullptr||result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get uri.");
    }
    // 尝试获取mediaAsset中的displayName信息。
    const char* displayName = nullptr;
    result = OH_MediaAsset_GetDisplayName(mediaAsset, &displayName);
    if (displayName == nullptr||result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get displayName.");
    }
    // 尝试获取mediaAsset中的size信息。
    uint32_t mediaAssetSize = 0;
    result = OH_MediaAsset_GetSize(mediaAsset, &mediaAssetSize);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get size.");
    }
    // 尝试获取mediaAsset中的修改时间信息。
    uint32_t modifiedMs = 0;
    result = OH_MediaAsset_GetDateModifiedMs(mediaAsset, &modifiedMs);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get modifiedMs.");
    }
    // 尝试获取mediaAsset中的图片宽度信息。
    uint32_t width = 0;
    result = OH_MediaAsset_GetWidth(mediaAsset, &width);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get width.");
    }
    // 尝试获取mediaAsset中的图片高度信息。
    uint32_t height = 0;
    result = OH_MediaAsset_GetHeight(mediaAsset, &height);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get height.");
    }
    // 尝试获取mediaAsset中的图片方向信息。
    uint32_t orientation = 0;
    result = OH_MediaAsset_GetOrientation(mediaAsset, &orientation);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to get orientation.");
    }
    // 创建媒体资产管理对象。
    OH_MediaAssetManager* mediaAssetManager = OH_MediaAssetManager_Create();
    if (mediaAssetManager == nullptr) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to create mediaAssetManager.");
        return;
    }

    // 创建媒体资产变更请求。
    OH_MediaAssetChangeRequest* changeRequest = OH_MediaAssetChangeRequest_Create(mediaAsset);
    if (changeRequest == nullptr) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to create changeRequest.");
    }
    // 注册媒体资产快速请求回调。
    MediaLibrary_RequestOptions requestOptions;
    requestOptions.deliveryMode = MEDIA_LIBRARY_BALANCED_MODE;
    MediaLibrary_RequestId requestId;
    result = OH_MediaAssetManager_QuickRequestImage(mediaAssetManager, mediaAsset, requestOptions, &requestId, OnRequestQuickImageDataPreparedWithDetails);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to quick image.");
    }
    // 创建媒体资产保存变更请求。
    result = OH_MediaAssetChangeRequest_SaveCameraPhoto(changeRequest, MediaLibrary_ImageFileType::MEDIA_LIBRARY_IMAGE_JPEG);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to save camera photo.");
    }
    result = OH_MediaAccessHelper_ApplyChanges(changeRequest);
    if (result != MEDIA_LIBRARY_OK) {
        OH_LOG_ERROR(LOG_APP, "OnPhotoAssetAvailable failed to apply changes.");
    }
}

// 注册分段式拍照回调函数。
Camera_ErrorCode RegisterPhotoAssetAvailable(Camera_PhotoOutput* photoOutput)
{
    Camera_ErrorCode ret = OH_PhotoOutput_RegisterPhotoAssetAvailableCallback(photoOutput, OnPhotoAssetAvailable);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "RegisterPhotoAssetAvailable failed. %d ", ret);
    }
    return ret;
}
// 解注册分段式拍照回调函数。
Camera_ErrorCode UnregisterPhotoAssetAvailable(Camera_PhotoOutput* photoOutput)
{
    Camera_ErrorCode ret = OH_PhotoOutput_UnregisterPhotoAssetAvailableCallback(photoOutput, OnPhotoAssetAvailable);
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "UnregisterPhotoAssetAvailable failed. %d ", ret);
    }
    return ret;
}

  7. 创建拍照类型会话（参考会话管理(C/C++)），开启会话，准备拍照。

  8. 触发拍照。

    通过OH_PhotoOutput_Capture()方法，执行拍照任务。

    Camera_ErrorCode Capture(Camera_PhotoOutput* photoOutput)
{
    Camera_ErrorCode 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);
    }
    return ret;
}

状态监听

在相机应用开发过程中，可以随时监听拍照输出流状态，包括拍照流开始、拍照帧的开始与结束、拍摄下一张图片是否就绪、拍照输出流的错误。

  • 通过注册固定的onFrameStart回调函数获取监听拍照开始结果，当photoOutput创建成功时，即可监听。拍照第一次曝光时触发。

    void PhotoOutputOnFrameStart(Camera_PhotoOutput* photoOutput)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutputOnFrameStart");
}
void PhotoOutputOnFrameShutter(Camera_PhotoOutput* photoOutput, Camera_FrameShutterInfo* info)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutputOnFrameShutter");
}

  • 通过注册固定的onFrameEnd回调函数监听拍照结束结果，当photoOutput创建成功时，即可监听。

    void PhotoOutputOnFrameEnd(Camera_PhotoOutput* photoOutput, int32_t frameCount)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutput frameCount = %{public}d", frameCount);
}

  • 通过注册固定的captureReady回调函数监听能否继续拍摄下一张的结果，当photoOutput创建成功时，即可监听。当下一张可拍时触发，该事件返回结果为下一张可拍的相关信息。

    static bool g_captureReadyFlag = false;
void CaptureReadyCb(Camera_PhotoOutput* photoOutput) {
  g_captureReadyFlag = true;
  OH_LOG_INFO(LOG_APP, "PhotoOutputOnCaptureReady captureReadyFlag = %{public}d", g_captureReadyFlag);
}

void OnPhotoOutputOnCaptureReady(Camera_PhotoOutput* photoOutput)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutputOnCaptureReady");
    Camera_ErrorCode ret = OH_PhotoOutput_RegisterCaptureReadyCallback(photoOutput, CaptureReadyCb);
}

  • 通过注册固定的onError回调函数获取监听拍照输出流的错误结果。callback返回拍照输出接口使用错误时的对应错误码，错误码类型参见Camera_ErrorCode。

    void PhotoOutputOnError(Camera_PhotoOutput* photoOutput, Camera_ErrorCode errorCode)
{
    OH_LOG_INFO(LOG_APP, "PhotoOutput errorCode = %{public}d", errorCode);
}

    PhotoOutput_Callbacks* GetPhotoOutputListener()
{
    static PhotoOutput_Callbacks photoOutputListener = {
        .onFrameStart = PhotoOutputOnFrameStart,
        .onFrameShutter = PhotoOutputOnFrameShutter,
        .onFrameEnd = PhotoOutputOnFrameEnd,
        .onError = PhotoOutputOnError
    };
    return &photoOutputListener;
}
Camera_ErrorCode RegisterPhotoOutputCallback(Camera_PhotoOutput* photoOutput)
{
    Camera_ErrorCode ret = OH_PhotoOutput_RegisterCallback(photoOutput, GetPhotoOutputListener());
    if (ret != CAMERA_OK) {
        OH_LOG_ERROR(LOG_APP, "OH_PhotoOutput_RegisterCallback failed.");
    }
    return ret;
}

你可能感兴趣的鸿蒙文章

openharmony 鸿蒙 camera-whitebalance

openharmony 鸿蒙 native-camera-preview

openharmony 鸿蒙 camera-worker

openharmony 鸿蒙 camera-background-recovery

openharmony 鸿蒙 camera-preparation

openharmony 鸿蒙 camera-shooting

openharmony 鸿蒙 camera-moving-photo

openharmony 鸿蒙 camera-system-pressure

openharmony 鸿蒙 native-camera-preview-imageReceiver

openharmony 鸿蒙 native-camera-shooting

  • 所属分类： 后端技术
  • 本文标签： 鸿蒙 软件
  • 版权声明： 本文链接 https://seaxiang.com/blog/sHW06rLO