c++ - 不能在opencv C++中扭曲背面图像

Question

我试图在 opencv 中扭曲图像。起初，由于 cv::undistort(raw, undist, cameraMatrix, distCoeffs); 可以正常工作，用针孔相机拍摄的图像没有失真。现在，我正在尝试使用我在此处找到的补丁将 undist 扭曲回其原始状态:http://code.opencv.org/issues/1387 但到目前为止，我还没有设法让它发挥作用。这是代码:

void distort(const cv::Mat& src, cv::Mat& dst, const cv::Mat& cameraMatrix, const cv::Mat& distCoeffs)
{

  cv::Mat pixel_locations_src = cv::Mat(src.size(), CV_32FC2);

  for (int i = 0; i < src.size().height; i++) {
    for (int j = 0; j < src.size().width; j++) {
      pixel_locations_src.at<cv::Point2f>(i,j) = cv::Point2f(j,i);
    }
  }

  cv::Mat fractional_locations_dst = cv::Mat(src.size(), CV_32FC2);

  cv::Mat pixel_locations_dst = cv::Mat(src.size(), CV_32FC2);

  cv::undistortPoints(pixel_locations_src, pixel_locations_dst, cameraMatrix, distCoeffs);

  const float fx = cameraMatrix.at<double>(0,0);
  const float fy = cameraMatrix.at<double>(1,1);
  const float cx = cameraMatrix.at<double>(0,2);
  const float cy = cameraMatrix.at<double>(1,2);

  // is there a faster way to do this?
  for (int i = 0; i < fractional_locations_dst.size().height; i++) {
    for (int j = 0; j < fractional_locations_dst.size().width; j++) {
      const float x = fractional_locations_dst.at<cv::Point2f>(i,j).x*fx + cx;
      const float y = fractional_locations_dst.at<cv::Point2f>(i,j).y*fy + cy;
      pixel_locations_dst.at<cv::Point2f>(i,j) = cv::Point2f(x,y);
    }
  }

  cv::remap(src, dst, pixel_locations_dst, cv::Mat(), CV_INTER_LINEAR);
}

我试图将 RGB 图像传递给该函数，但由于 undistortPoints 采用 1*N、2 channel 矩阵，代码将在 undistortPoints 处触发断言，我不知道不明白为什么 distort() 将 1xN 矩阵作为输入。

任何有关该主题的信息都会很棒。谢谢

Answer 1

我最终采用了不同的方法，我只需要扭曲回特定的一组点，代码如下:

void DistortPoints(const std::vector<cv::Point2f> & src, std::vector<cv::Point2f> & dst, const cv::Mat& cameraMatrix, const cv::Mat& distorsionMatrix)
{
    double fx = cameraMatrix.at<double>(0,0);
    double fy = cameraMatrix.at<double>(1,1);
    double cx = cameraMatrix.at<double>(0,2);
    double cy = cameraMatrix.at<double>(1,2);
    std::vector<cv::Point3f> src2;

    for (int i = 0; i < src.size(); i++)
        src2.push_back(cv::Point3f((src[i].x - cx) / fx, (src[i].y - cy) / fy, 0));

    cv::Mat rVec(3, 1, cv::DataType<double>::type, cv::Scalar(0)); // Rotation vector
    cv::Mat tVec(3, 1, cv::DataType<double>::type, cv::Scalar(0)); // Translation vector

    std::vector<cv::Point2f> dst2;
    cv::projectPoints(src2, rVec, tVec, cameraMatrix, distorsionMatrix, dst);
}