拍照开发指导

    表 1 API列表

    无。

    1. 实现设备状态回调的派生类，用户在设备状态发生变更（如新插入相机设备/相机掉线）时，自定义操作。

    2. 实现帧事件回调的派生类，这里在拿到帧数据以后将其转存为文件。

      2. {
      3.     cout << "Start saving picture" << endl;
      4.     struct timeval tv;
      5.     gettimeofday(&tv, NULL);
      6.     struct tm *ltm = localtime(&tv.tv_sec);
      7.     if (ltm != nullptr) {
      8.         ostringstream ss("Capture_");
      9.         ss << "Capture" << ltm->tm_hour << "-" << ltm->tm_min << "-" << ltm->tm_sec << ".jpg";
      11.         ofstream pic("/sdcard/" + ss.str(), ofstream::out | ofstream::trunc);
      12.         cout << "write " << size << " bytes" << endl;
      13.         pic.write(p, size);
      14.         cout << "Saving picture end" << endl;
      15.     }
      16. }
      18. class TestFrameStateCallback : public FrameStateCallback {
      19.     void OnFrameFinished(Camera &camera, FrameConfig &fc, FrameResult &result) override
      20.     {
      21.         cout << "Receive frame complete inform." << endl;
      22.         if (fc.GetFrameConfigType() == FRAME_CONFIG_CAPTURE) {
      23.             list<Surface *> surfaceList = fc.GetSurfaces();
      24.             for (Surface *surface : surfaceList) {
      26.                 if (buffer != nullptr) {
      27.                     char *virtAddr = static_cast<char *>(buffer->GetVirAddr());
      28.                     if (virtAddr != nullptr) {
      29.                         SampleSaveCapture(virtAddr, buffer->GetSize());
      30.                     }
      31.                     surface->ReleaseBuffer(buffer);
      32.                 }
      33.                 delete surface;
      34.             }
      35.             delete &fc;
      36.         }
      37.     }
      38. };

    3. 实现相机状态回调的派生类，当相机状态发生变化（配置成功/失败，创建成功/失败)时，自定义操作。

    4. 创建CameraKit，用于创建和获取camera信息。

      1. CameraKit *camKit = CameraKit::GetInstance();
      2. list<string> camList = camKit->GetCameraIds();
      3. string camId;
      4. for (auto &cam : camList) {
      5.     cout << "camera name:" << cam << endl;
      6.     const CameraAbility *ability = camKit->GetCameraAbility(cam);
      7.     /* find camera which fits user's ability */
      8.     list<CameraPicSize> sizeList = ability->GetSupportedSizes(0);
      9.     if (find(sizeList.begin(), sizeList.end(), CAM_PIC_1080P) != sizeList.end()) {
      10.         camId = cam;
      12. }

    5. 创建Camera实例。

      1. void OnCreated(Camera &c) override
      2. {
      3.     cout << "Sample recv OnCreate camera." << endl;
      4.     auto config = CameraConfig::CreateCameraConfig();
      5.     config->SetFrameStateCallback(&fsCb_, &eventHdlr_);
      6.     c.Configure(*config);
      7.     cam_ = &c;
      8. }
      10. void Capture()
      11. {
      12.     if (cam_ == nullptr) {
      13.         cout << "Camera is not ready." << endl;
      14.         return;
      15.     }
      16.     FrameConfig *fc = new FrameConfig(FRAME_CONFIG_CAPTURE);
      17.     Surface *surface = Surface::CreateSurface();
      18.     if (surface == nullptr) {
      19.         delete fc;
      20.     }
      21.     surface->SetWidthAndHeight(1920, 1080); /* 1920:width,1080:height */
      22.     fc->AddSurface(*surface);
      23.     cam_->TriggerSingleCapture(*fc);