Patent Document ID: 9237354
Application ID: 13630753
Patent Status: 1

Claim One:
1. A video coding apparatus comprising: a motion vector detector configured to detect a first motion vector from a first reference image for a coding target block; a reference image composition unit configured to create a composite reference block that a first reference block of a specific region having a size equal to the coding target block or larger, the first reference block having been extracted from the first reference image using the first motion vector, has been composited with a predetermined region of at least one of other reference images; a motion compensated prediction unit configured to detect a second motion vector corresponding to the coding target block for the composite reference block by searching the specific region in the composite reference block, extract a block of the same size as the coding target block from the composite reference block using the second motion vector, and set the extracted block as a prediction block; and a coding unit configured to code a prediction difference block that the prediction block has been subtracted from the coding target block, and the second motion vector, wherein the accuracy of the first motion vector is N pixel accuracy (N is a real number), and the accuracy of the second motion vector is M pixel accuracy (M is a real number: M<N), and the specific region has a region equal to a target block ±N/2 pixel or more, relative to a position in the first reference image, the position being pointed by the first motion vector or a vector value that has converted the first motion vector to N pixel accuracy (N is a real number), and a range to detect the second motion vector is within a range of ±N/2 with respect to the first motion vector value.