opencv 图像清晰度判断方法

if (matRaw.empty()) return;
  matRes = matRaw.clone();
  cv::Mat mgray;
  cv::cvtColor(matRes, mgray, cv::COLOR_BGR2GRAY);

  QDateTime dtcur = QDateTime::currentDateTime();

  cv::Mat mlap;
  cv::Laplacian(mgray, mlap, CV_16U);  // Laplacian梯度方法
  //  cv::Sobel(mgray, mlap, CV_16U, 1, 1);//Tenengrad梯度方法

  qDebug() << "Laplacian cost ms:"
           << dtcur.msecsTo(QDateTime::currentDateTime());

  double meanvalue = cv::mean(mlap)[0];

  qDebug() << "meanvalue:" << meanvalue;

  QString strres = QString("score:%1").arg(meanvalue);
  cv::putText(matRes, strres.toStdString(), cv::Point(100, 100),
              CV_FONT_HERSHEY_SIMPLEX, 3, cv::Scalar(0, 0, 255), 3);

  displayMat(matRes, ui->labelPicResult);