| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide technology for improving coefficient density of an orthogonal transformation coefficient.SOLUTION: A moving image encoder and a moving image decoder include: an acquisition section for acquiring a transformation coefficient from encoded data; a coefficient order control section for rearranging the transformation coefficient in accordance with a scan order corresponding to a prediction direction of an object block in scan orders which are previously determined for respective prediction directions; a classification section for classifying a processing mode of the object block to a first mode or a second mode; a first inverse orthogonal transformation section for inversely and orthogonally transforming the rearranged transformation coefficient by using a common first transformation basis irrespective of the prediction direction; a second inverse orthogonal transformation section for inversely and orthogonally transforming the rearranged transformation coefficient by using a second transformation basis different from the first transformation basis when the processing mode is classified to the second mode; and a decoded image signal generation section for generating a decoded image signal by using a prediction error signal. When the prediction direction of the object block is a vertical direction, the coefficient order control section rearranges the transformation coefficient in accordance with the scan order in a horizontal direction.</p> |
