MOVEMENT VECTOR CODER

摘要

PURPOSE:To attain variable length coding with an excellent coding efficiency by storing a difference code in a difference code memory and transferring the difference code to a variable length coder in a preset order by the use of a memory data controller. CONSTITUTION:A movement vector is stored in a delay device 101. A difference period counter 102 counts the number of blocks to reset the delay device 101 every difference period. A difference coder 103 codes a difference between a current movement vector value and a stored value in the delay device 101 and stores the difference to a difference code memory 105. A memory data controller 106 transfers the difference code stored in the difference code memory 105 in the preset order to the variable length coder 104 synchronously with the difference period counter 102. In this case, the coding efficiency is improved by using a rearrangement pattern in which the number of difference codes of consecutive 0s is increased for example.