How to save and load Matx from a file?
When trying to save a cv::Matx to a file using FileStorage, openCV throws some errors which say saving a Matx is not yet implemented. A workaround is to cast the Matx to a cv::Mat when writing:
cv::FileStorage fs("file.xml", cv::FileStorage::WRITE);
cv::Matx33d x;
fs<<"X"<<cv::Mat(x); // file contains x
However, when loading a cv::Matx from file, simply casting it to cv::Mat does not work. I assume the result is not copied, and the Matx is left uninitialized:
cv::FileStorage fs("file.xml", cv::FileStorage::READ);
cv::Matx33d x;
fs["X"]>>cv::Mat(x); // x contains gibberish
Is there a simple workaround for this, without resorting to creating temporary cv::Mat's and casting them to Matx after reading?
Have you try something like x=(cv::Mat)fs(["X"]);
Using x=(cv::Mat)(fs["X"]) produces the error "cannot convert from 'cv::FileNode' to 'cv::Mat' "
even if you use a temporary Mat, you have to invert the casting order: