A method, apparatus, and system for determining a horizontal resolution and a phase of an analog video signal arranged to display a number of scan lines each formed of a number of pixels is described. A number of initialization values are set where at least one of the initialization values is a current horizontal resolution and then a difference value for each immediately adjacent ones of the pixels is determined. Next, an edge flag value based upon the difference value is stored in at least one of a number of accumulators such that when at least one of the accumulators has a stored edge flag value that is substantially greater than those stored edge flag values in the other accumulators, then the horizontal resolution is set to the current resolution.