Advances on the Detection and Measurement of Bubble Contours During Subcooled Boiling in Microgravity

A method for the detection of bubble contours in images of subcooled boiling in microgravity is proposed. The method refines an initial, rough contour approximation obtained from conventional background subtraction techniques. This refinement entails the warping of an elliptical ring image region that warps this ring into an elliptical polar image, where contour edge detection is simpler. The proposed method exhibits robustness to a wide variety of visual phenomena that typically hinder the detection of bubble contours. This is achieved by the grouping of continuous image edges and their accordance with the initial rough approximation of the contour. A ground truth annotated data set is provided for future research(ers) so that improvements to the proposed method can be documented.