The device employs a plurality of coefficients recorded in image data to detect whether edges are included per block, and determines as the blur level the proportion of edges, among the detected edges, in which the edge width is over a certain threshold. A method is provided to apply the perianal support device to patients during childbirth to inhibit the formation andor progression of tissue damage in the perianal region of the body. The system transfers a quantity of thermal energy from the liquid to the vapor-added process gas, and is also capable of upgrading the thermal energy to a higher temperature. The folding process is carried out in several stages, one flange being crimped around another flange in a series of partial steps at an angle of 180\xb0. At least one of the first blade and the second blade is movable toward and away from the other of the first blade and the second blade to have an opened position and a pinch position.