| 摘要 |
An encoder for compressing video sequences using motion compensation comprises motion compensated predictor (41) for producing a prediction frame pn(x,y) using estimated motion vectors DELTA x(x,y), DELTA y(x,y) of the current frame In(x,y) being compressed and pixels of a reference frame Rn(x,y), and means for producing a prediction error En(x,y), which is a difference between the current frame and the prediction frame. The motion compensated predictor (41) comprises means for generating motion vector field of the form (a) and (b), where N, M, fi, gi, pi and qi are fixed coefficients. Calculation means (43) minimizes a measure of the prediction error, wherein the coefficients ai, bi giving the minimum measure are transmitted to the decoder. |
