| 摘要 |
An image encoding device that appropriately estimates a prediction vector by avoiding an uncoded macro block (MB) is disclosed. The device determines a start point of searching a motion vector for an encoding target region, from the prediction vector for the target region which is determined with motion vectors for surrounding blocks around the target region and in accordance with a predetermined rule, and starts searching for the motion vector from the search start point. If the size of the encoding target region cannot be acquired during calculation of the prediction vector, the device determines the size of the encoding target region, from the size of an encoded region other than the target region. If at least one of the motion vectors for the surrounding blocks cannot be acquired, the device calculates the prediction vector using alternatively a motion vector of an encoded block outside of the target region. |
