The invention provides a method and an apparatus for inspecting an object employing machine vision. A machine vision system including a digital camera can be employed to inspect an object in a field of view, including capturing an original digital image including a multiplicity of pixels and associated light intensities for the field of view including the object. A bitmap image file is generated, and a mean value and a standard deviation of the light intensities of the multiplicity of pixels of the bitmap image file for the original digital image are dynamically determined. New image files are generated, each including a portion of the multiplicity of pixels having associated light intensities within a prescribed range of light intensities defined by the mean value and the standard deviation. Line segments are extracted from each of the new image files, and the extracted line segments from the new image files are merged and clustered to generate integral lines based thereon.