摘要 |
A method of controlling frame types in a video compression system having I, P and B frames calculates activity figures of the video signal in vertical, vertical temporal and horizontal directions. Video sequences with low complexity in which the vertical activity within a field is less than the vertical-temporal activity within a frame are encoded without using B frames whereas sequences with high complexity, i.e. spatial detail, are encoded using B frames by the use of the invention, disadvantages associated with B frames are reduced by the selected use of B frames. |