Video encoding apparatus and video decoding apparatus

A video decoding method for subjecting a video image to motion compensated decoding, the method comprising:

• acquiring available blocks having motion vectors and number of the available blocks from decoded blocks adjacent to a to-be-decoded block;
• decoding selection information specifying the available block using a code table corresponding to the number of the available blocks and not decoding the selection information when the number of available blocks is 1;
• selecting one selection block from the available blocks according to the selection information;
• and
• subjecting the to-be-decoded block to a motion compensated prediction decoding using a motion vector of the selected block.

A computer program for causing a computer to subject a video image to motion compensated decoding, the program causing the computer to execute

• a step of acquiring available blocks having motion vectors and a number of the available blocks from decoded blocks adjacent to a to-be-decoded block;
• a step of decoding selection information specifying the available block using a code table corresponding to the number of the available blocks and not decoding the selection information when the number of available blocks is 1;
• a step of selecting one selection block from the available blocks according to the selection information;
• and
• a step of subjecting the to-be-decoded block to a motion compensated prediction decoding using a motion vector of the selected block.

A video decoding apparatus for subjecting a video image to motion compensated decoding, the apparatus decoding an encoded data by performing:

• acquiring available blocks having motion vectors and a number of the available blocks from decoded blocks adjacent to a to-be-decoded block;
• decoding selection information specifying the available block using a code table corresponding to the number of the available blocks and not to decode the selection information when the number of available blocks is 1;
• selecting one selection block from the available blocks according to the selection information;
• and
• subjecting the to-be-decoded block to a motion compensated prediction decoding using a motion vector of the selected block.

A video decoding method for subjecting a video image to motion compensated decoding, the method decoding an encoded data by performing:

• acquiring available blocks having motion vectors and number of the available blocks from decoded blocks adjacent to a to-be-decoded block;
• decoding selection information specifying the available block using a code table corresponding to the number of the available blocks and not to decode the selection information when the number of available blocks is 1;
• selecting one selection block from the available blocks according to the selection information;
• and
• subjecting the to-be-decoded block to a motion compensated prediction decoding using a motion vector of the selected block.