15 Mark R. Banham James C. Brailean Stephen N. Levine Aggelos K. Katsaggelos Guido M. Schuster 1998 5,764,921 United States Motorola, Inc., Northwestern University 09/07/1998 A method (100, 200), device (300) and microprocessor (400) are provided for selectively compressing video frames of a motion compensated prediction-based video codec based on a predetermined set of compression techniques. An energy estimate of the current displaced frame difference, DFD, is used to compute a ratio between the estimate and a historical mean of energy estimates. The ratio is iteratively compared to a predetermined set of thresholds which are associated with the predetermined set of compression techniques. The comparisons are used to choose a technique based on the thresholds, and a technique is selected to be used for encoding the current DFD.