Moving picture coding method, and moving picture decoding method

摘要

A moving picture coding apparatus for performing inter-picture predictive coding on pictures constituting a moving picture is provided with a coding unit for performing predictive error coding on image data; a decoding unit for performing predictive error decoding on an output from the coding unit; a reference picture memory for holding output data from the decoding unit; and a motion vector detection unit for detecting forward and backward motion vectors on the basis of decoded image data stored in the memory. When coding a B picture, a picture that is timewise closest to the target picture is used as a candidate picture for forward reference, and an I or P picture that is timewise closest to the target picture is used as a candidate picture for backward reference. The moving picture coding apparatus so constructed can improve coding efficiency of a B picture to be subjected to bidirectional predictive coding.