MOTION VECTOR FIELD CODING

A video codec includes a motion field coder for minimizing the number of motion coefficients of a motion vector field. In the coder, a first block includes forming a new matrix representation of the motion vector field. The new coded motion vector field is linear. A second main block includes merging pairs of adjacent segments if the combined segment area can be predicted using a common motion field. Merging information is transmitted to a decoder. A third main block includes removing motion field basis functions. After each removing step, the squared prediction error is calculated and removing is continued until the chance of the error is not acceptable. Final motion coefficients are calculated by solving a linear matrix equation. As a result, reduced number of motion coefficients of each segment are obtained. The motion coefficients are transmitted to the decoder.