Coded image bit stream format converter

摘要

A format converter which receives a compressed image bit stream removes the requirement for separate motion vector calculation in the decoding and conversion steps. The bit stream (a) is input to an extracting unit (1a) for the extraction of coding control data (m), including motion vectors, used by the decoder unit (1b). The motion vectors from the coding control data extracting unit (1a) are used by a motion vector calculating unit (2a) in the format converter (2), together with interpolated field position data (p) to calculate the motion vectors (n) to be used by the format converter (2b). These motion vectors (n) are subsequently fed, together with coding control data (m) and field position data (p), to a coding controller (3a) to generate further motion vectors (q) for the final encoding unit (3b).