Motion image encoding apparatus, motion image decoding apparatus, motion image encoding method, motion image decoding method, motion image encoding program, and motion image decoding program

A motion image decoding apparatus for generating a prediction block in blocks, comprising:

• a storing means for storing a decoded image;
• a decoding means for generating a low-resolution block with a smaller number of pixels than that of a prediction block by decoding inputted encoded data;
• an enhancing means for enhancing the generated low-resolution block to a block with the same number of pixels as that of the prediction block;
• a dividing means for generating plural small blocks by dividing the enhanced block based on a predetermined division rule;
• a predicting means for generating a predicted small block of the small block using the decoded image and the divided small block;
• and
• a combining means for generating a prediction block by combining the generated plural predicted small blocks based on the division rule.

A motion image encoding method for generating a prediction block using a decoded image in blocks, comprising:

• a first dividing step for dividing an inputted target image to be encoded into plural target blocks to be predicted;
• a generating step for transforming the target block to be predicted into a low-resolution block with a smaller number of pixels than that of the target block to be predicted, and encoding the low-resolution block and generating a decoded low-resolution block by decoding the encoded data of the low-resolution block;
• an enhancing step for enhancing the generated decoded low-resolution block to a block with the same number of pixels as that of the target block to be predicted;
• a second dividing step for generating plural small blocks by dividing the enhanced block based on a predetermined division rule;
• a predicting step for generating a predicted small block of the small block using the decoded image and the generated small block;
• and
• a combining step for generating a prediction block by combining the generated plural predicted small blocks based on the division rule.

A motion image decoding method for generating a prediction block using a decoded image in blocks, comprising:

• a decoding step for generating a low-resolution block with a smaller number of pixels than that of a prediction block by decoding input encoded data;
• an enhancing step for enhancing the generated low-resolution block to a block with the same number of pixels as that of the prediction block;
• a dividing step for generating plural small blocks by dividing the enhanced block based on a predetermined division rule;
• a predicting step for generating a predicted small block of the small block using the decoded image and the divided small block;
• and
• a combining step for generating a prediction block by combining the generated plural predicted small blocks based on the division rule.

A motion image encoding program for causing a computer provided with a storing means for storing a decoded image and a motion image encoding program having a function of generating a prediction block in blocks to perform:

• a first dividing process for dividing a target image to be encoded into plural target blocks to be predicted;
• a generating process for transforming the target block to be predicted into a low-resolution block with a smaller number of pixels than that of the target block to be predicted, encoding the low-resolution block and generating a decoded low-resolution block by decoding the encoded data of the low-resolution block;
• an enhancing process for enhancing the generated decoded low-resolution block to a block with the same number of pixels as that of the target block to be predicted;
• a second dividing process for generating plural small blocks by dividing the enhanced block based on a predetermined division rule;
• a predicting process for generating a predicted small block of the small block using the decoded image and the generated small block;
• and
• a combining process for generating a prediction block by combining the generated plural predicted small blocks based on the division rule.

A motion image decoding program for causing a computer provided with a storing means for storing a decoded image and a motion image decoding program having a function of generating a prediction block in blocks to perform:

• a decoding process for generating a low-resolution block with a smaller number of pixels than that of a prediction block by decoding input encoded data;
• an enhancing process for enhancing the generated low-resolution block to a block with the same number of pixels as that of the prediction block;
• a dividing process for generating plural small blocks by dividing the enhanced block based on a predetermined division rule;
• a predicting process for generating a predicted small block of the small block using the decoded image and the divided small block;
• and
• a combining process for generating a prediction block by combining the generated plural predicted small blocks based on the division rule.

A motion image decoding apparatus for generating a prediction block by decoding target encoded data to be decoded in predetermined blocks, comprising:

• a storing means for storing a decoded image;
• an entropy decoding means for generating low-resolution block information, which is an encoded low-resolution block having a smaller number of pixels than that of the decoded block and having temporally and spatially the same position as that of the decoded block, by entropy decoding inputted encoded data;
• a low-resolution block decoding means for decoding the low-resolution block information generated by the entropy decoding means and generating the low-resolution block while referring to the decoded image;
• a low-resolution block dividing means for generating plural low-resolution divided blocks by dividing the low-resolution block generated by the low-resolution block decoding means based on a predetermined division rule;
• a predicted small block generating means for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated by the low-resolution block dividing means;
• and
• a block combining means for generating a prediction block by combining the predicted small blocks generated by the predicted small block generating means based on a predetermined combination rule in accordance with the division rule.

A motion image encoding apparatus for generating a prediction block by encoding a target image to be encoded in predetermined blocks, comprising:

• a storing means for storing a decoded image;
• a coding block dividing means for dividing an inputted image into plural target blocks to be encoded;
• a decoded low-resolution block generating means for generating low-resolution block information upon encoding a low-resolution block having a smaller number of pixels than that of the target block to be encoded divided by the coding block dividing means and having temporally and spatially the same position as that of the target block to be encoded, decoding the low-resolution block information, and generating a decoded low-resolution block upon referring to the decoded image;
• a low-resolution block dividing means for generating plural low-resolution divided blocks by dividing the decoded low-resolution block generated by the decoded low-resolution block generating means based on a predetermined division rule;
• a predicted small block generating means for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated by the low-resolution block dividing means;
• and
• a block combining means for generating a prediction block by combining the predicted small blocks generated by the predicted small block generating means based on a predetermined combination rule in accordance with the division rule.

A motion image decoding method for a motion image decoding apparatus having a storing means for storing a decoded image and generating a prediction block by decoding target encoded data to be decoded in predetermined blocks, comprising:

• an entropy decoding process for generating low-resolution block information, which is an encoded low-resolution block having a smaller number of pixels than that of the decoded block and having temporally and spatially the same position as that of the decoded block, by entropy decoding inputted encoded data to be decoded;
• a low-resolution block decoding process for decoding the low-resolution block information generated in the entropy decoding process and generating the low-resolution block while referring to the decoded image;
• a low-resolution block dividing process for generating plural low-resolution divided blocks by dividing the low-resolution block generated in the low-resolution block decoding process based on a predetermined division rule;
• a predicted small block generating process for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated in the low-resolution block dividing process;
• and
• a block combining process for generating a prediction block by combining the predicted small blocks generated in the predicted small block generating process based on a predetermined combination rule in accordance with the division rule.

A motion image encoding method for a motion image encoding apparatus having a storing means for storing a decoded image and generating a prediction block by encoding a target image to be encoded in predetermined blocks, comprising:

• a coding block dividing process for dividing a target image to be encoded into plural target blocks to be encoded;
• a decoded low-resolution block generating process for generating low-resolution block information upon encoding a low-resolution block having a smaller number of pixels than that of the target block to be encoded divided in the coding block dividing process and having temporally and spatially the same position as that of the target block to be encoded, decoding the low-resolution block information, and generating a decoded low-resolution block upon referring to the decoded image;
• a low-resolution block dividing process for generating plural low-resolution divided blocks by dividing the decoded low-resolution block generated in the decoded low-resolution block generating process based on a predetermined division rule;
• a predicted small block generating process for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated in the low-resolution block dividing process;
• and
• a block combining process for generating a prediction block by combining the predicted small blocks generated in the predicted small block generating process based on a predetermined combination rule in accordance with the division rule.

A motion image decoding program for causing a computer provided in a motion image decoding apparatus having a storing means for storing a decoded image and generating a prediction block by decoding target encoded data to be decoded in predetermined blocks to function as:

• an entropy decoding means for generating low-resolution block information, which is an encoded low-resolution block having a smaller number of pixels than that of the decoded block and having temporally and spatially the same position as that of the decoded block, by entropy decoding inputted encoded data to be decoded;
• a low-resolution block decoding means for decoding the low-resolution block information generated by the entropy decoding means and generating the low-resolution block while referring to the decoded image;
• a low-resolution block dividing means for generating plural low-resolution divided blocks by dividing the low-resolution block generated by the low-resolution block decoding means based on a predetermined division rule;
• a predicted small block generating means for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated by the low-resolution block dividing means;
• and
• a block combining means for generating a prediction block by combining the predicted small blocks generated by the predicted small block generating means based on a predetermined combination rule in accordance with the division rule.

A motion image encoding program for causing a computer provided in a motion image encoding apparatus having a storing means for storing a decoded image and generating a prediction block by encoding a target image to be encoded in predetermined blocks to function as:

• a coding block dividing means for dividing an inputted image to be encoded into plural target blocks to be encoded;
• a decoded low-resolution block generating means for generating low-resolution block information upon encoding a low-resolution block having a smaller number of pixels than that of the target block to be encoded divided by the coding block dividing means and having temporally and spatially the same position as that of the target block to be encoded, decoding the low-resolution block information, and generating a decoded low-resolution block upon referring to the decoded image;
• a low-resolution block dividing means for generating plural low-resolution divided blocks by dividing the decoded low-resolution block generated by the decoded low-resolution block generating means based on a predetermined division rule;
• a predicted small block generating means for generating a predicted small block having a larger number of pixels than that of the low-resolution divided block and having temporally and spatially the same position as that of the low-resolution divided block using the decoded image stored by the storing means and the low-resolution divided block generated by the low-resolution block dividing means;
• and
• a block combining means for generating a prediction block by combining the predicted small blocks generated by the predicted small block generating means based on a predetermined combination rule in accordance with the division rule.