Mat processingImage = halved_gray_current_frame(readingHeadProcessingAreaRect);
// Algorithm and parameters
// for informations about the Generalized Hough Guild interface see the tutorial at https://docs.opencv.org/4.7.0/da/ddc/tutorial_generalized_hough_ballard_guil.html
int capstanProcessingAreaRectWidth = myFrame.cols/4;
int capstanProcessingAreaRectHeight = myFrame.rows/2;
Rect capstanProcessingAreaRect(capstanProcessingAreaRectX, capstanProcessingAreaRectY, capstanProcessingAreaRectWidth, capstanProcessingAreaRectHeight);