A method for performing plunger depth inspection for a vessel having a plunger (305, 704), comprising: acquiring, via an imager (102, 240), an image of the vessel including a reference point region of interest, ROI, (302, 400) that encompasses an image of a reference point from which to measure plunger depth, and an initial plunger ROI that encompasses an image of the plunger; identifying, via a controller (104, 202), the reference point ROI and the initial plunger ROI in the image of the vessel; generating, via the controller, a binarized reference point image (450, 500, 650) based upon a blob analysis of the reference point ROI; calculating, via the controller, an uppermost vessel edge (310, 454, 508) within the binarized reference point image; aligning, via the controller, a refined plunger ROI (306, 308, 902) with the top of the plunger within the initial plunger ROI using a matching plunger image template from among a plurality of plunger image templates; calculating, via the controller, an uppermost plunger edge (312, 906) within the refined plunger ROI; and calculating, via the controller, a depth of the plunger within the vessel using a difference between respective coordinate values of the uppermost vessel edge and the uppermost plunger edge with respect to a direction perpendicular to a top surface of the plunger; wherein the act of calculating the uppermost plunger edge within the refined plunger ROI comprises: dividing the top of the refined plunger ROI into a plurality of columns; performing one-dimensional edge-detection on each of the plurality of columns to determine, for each column, a y-coordinate value associated with an upper edge of the plunger; binning the y-coordinate value in each of the plurality of columns in accordance with a histogram according to y-coordinate values; removing bins having less than a threshold number of elements to generate a constrained set of y-coordinate values; and calculating the uppermost plunger edge within the refined plunger ROI based upon the constrained set of y-coordinate values. acquiring, via an imager (102, 240), an image of the vessel including a reference point region of interest, ROI, (302, 400) that encompasses an image of a reference point from which to measure plunger depth, and an initial plunger ROI that encompasses an image of the plunger; identifying, via a controller (104, 202), the reference point ROI and the initial plunger ROI in the image of the vessel; generating, via the controller, a binarized reference point image (450, 500, 650) based upon a blob analysis of the reference point ROI; calculating, via the controller, an uppermost vessel edge (310, 454, 508) within the binarized reference point image; aligning, via the controller, a refined plunger ROI (306, 308, 902) with the top of the plunger within the initial plunger ROI using a matching plunger image template from among a plurality of plunger image templates; calculating, via the controller, an uppermost plunger edge (312, 906) within the refined plunger ROI; and calculating, via the controller, a depth of the plunger within the vessel using a difference between respective coordinate values of the uppermost vessel edge and the uppermost plunger edge with respect to a direction perpendicular to a top surface of the plunger; wherein the act of calculating the uppermost plunger edge within the refined plunger ROI comprises: dividing the top of the refined plunger ROI into a plurality of columns; performing one-dimensional edge-detection on each of the plurality of columns to determine, for each column, a y-coordinate value associated with an upper edge of the plunger; binning the y-coordinate value in each of the plurality of columns in accordance with a histogram according to y-coordinate values; removing bins having less than a threshold number of elements to generate a constrained set of y-coordinate values; and calculating the uppermost plunger edge within the refined plunger ROI based upon the constrained set of y-coordinate values. dividing the top of the refined plunger ROI into a plurality of columns; performing one-dimensional edge-detection on each of the plurality of columns to determine, for each column, a y-coordinate value associated with an upper edge of the plunger; binning the y-coordinate value in each of the plurality of columns in accordance with a histogram according to y-coordinate values; removing bins having less than a threshold number of elements to generate a constrained set of y-coordinate values; and calculating the uppermost plunger edge within the refined plunger ROI based upon the constrained set of y-coordinate values.