Patent ID: 7391468

Claim:
A method of convening an encoded video data at a frame rate expanded by including repeated video fields to a source video data at an original frame rate, comprising: applying a moving average filter with a weighting factor to calculate a continuously programmable threshold to determine whether fields of successive fields from successive frames of encoded video data could be considered identical or not, and measuring the total difference in luminance values of the successive fields relative to the continuously programmable threshold in order to detect a characteristic cadence of the encoded video signal, wherein the moving average filter detects the presence of still images in the encoded video data by detecting total difference in luminance of the successive fields and then calculating the average difference in luminance of the successive fields, where the average difference in luminance value indicates a degree of difference between the successive fields, wherein the encoded video data comprises TELECINE encoded video data, wherein for the successive frames, a difference value is calculated between the luminance values of the fields for each successive frame, and from the difference value a maximum absolute difference history is stored, along with a Sum of Absolute Differences (SAD), and wherein the programmable threshold is then calculated by applying a moving average filter with a weighting factor to a saturated SAD history over time.