1. A method of processing a video signal in a video processing unit, the video signal having an interlaced format and comprising a sequence of fields, the method comprising: obtaining motion indicators for blocks of a plurality of fields of the video signal; using said obtained motion indicators to determine cadence signatures for blocks of a field of said plurality of fields, wherein the cadence signatures are indicative of one or more cadences of the video signal; creating a histogram of determined cadence signatures of said blocks of said field; and determining the position of one or more peaks in the histogram to thereby determine one or more significant cadence signatures in said field; whereby the fields of the video signal are processed in accordance with one or more determined significant cadence signatures to thereby determine frames of the video signal.