Image encoding apparatus, image encoding method, recording medium and program, image decoding apparatus, image decoding method, and recording medium and program

An image decoding apparatus that decodes encoded data generated by performing hierarchical coding of images composing a moving image with a plurality of layers, the image decoding apparatus comprising:

• an information decoding unit that decodes a SEI message indicating constraint related to a decoding process of a tile set composed of one or more tiles, the SEI message including a top left tile index indicating a position of a top left tile included in the tile set;
• and
• a decoding unit that decodes a first tile set in a first image and a second tile set in a second image according to the SEI message, wherein the first image corresponds to a first layer and the second image corresponds to a second layer which is different from the first layer,
• wherein, in a case where the SEI massage is decoded by the information decoding unit, the second tile set is arranged, in the second image, at a position corresponding to the first tile set,
• wherein the decoding unit decodes the first tile set without reference to any tile set in the first image other than the first tile set, and decodes the second tile set without reference to any tile set in the second image other than the second tile set, and
• wherein, in a case where the SEI massage is decoded by the information decoding unit and the decoding unit decodes the first tile set with reference to at least a part of an area of the second image, the decoding unit decodes the first tile set, without reference to any tile set in the second image other than the second tile set.

An image encoding method that performs hierarchical coding of images composing a moving image with a plurality of layers, the image encoding method comprising:

• generating a second image, wherein the second image corresponds to a second layer which is different from a first layer to which the first image corresponds;
• and
• encoding a first tile set composed of one or more tiles in the first image and a second tile set composed of one or more tiles in the second image;
• wherein the second tile set is arranged, in the second image, at a position corresponding to the first tile set,
• wherein the first tile set is encoded without reference to any tile set in the first image other than the first tile set, and encodes the second tile set without reference to any tile set in the second image other than the second tile set,
• wherein, in a case where the first tile set is encoded with reference to at least apart of an area of the second image, the first tile set is encoded without reference to any tile set in the second image other than the second tile set,
• wherein a supplemental enhancement information (SEI) message is encoded indicating constraint related to a decoding process of the first tile set and the second tile set, and
• wherein the SEI message includes a top left tile index indicating a position of a top left tile included in a tile set.

An image decoding method that decodes encoded data generated by performing hierarchical coding of images composing a moving image with a plurality of layers, the image decoding method comprising:

• decoding a SEI message indicating constraint related to a decoding process of a tile set composed of one or more tiles, the SEI message including a top left tile index indicating a position of a top left tile included in the tile set;
• and
• decoding a first tile set in a first image and a second tile set in a second image according to the SEI message, wherein the first image corresponds to a first layer and the second image corresponds to a second layer which is different from the first layer,
• wherein, in a case where the SEI message is decoded, the second tile set is arranged, in the second image, at a position corresponding to the first tile set,
• wherein the first tile set is decoded without reference to any tile set in the first image other than the first tile set, and decodes the second tile set without reference to any tile set in the second image other than the second tile set, and
• wherein, in a case where the SEI message is decoded and the first tile set is decoded with reference to at least a part of an area of the second image, the first tile set is decoded, without reference to any tile set in the second image other than the second tile set.

A non-transitory computer readable storage medium storing a program to cause a computer to execute an image encoding method that performs hierarchical coding of images composing a moving image with a plurality of layers, the image encoding method comprising:

• generating a second image, wherein the second image corresponds to a second layer which is different from a first layer to which the first image corresponds;
• and
• encoding a first tile set composed of one or more tiles in the first image and a second tile set composed of one or more tiles in the second image;
• wherein the second tile set is arranged, in the second image, at a position corresponding to the first tile set,
• wherein the first tile set is encoded without reference to any tile set in the first image other than the first tile set, and encodes the second tile set without reference to any tile set in the second image other than the second tile set,
• wherein, in a case where the first tile set is encoded with reference to at least apart of an area of the second image, the first tile set is encoded without reference to any tile set in the second image other than the second tile set,
• wherein a supplemental enhancement information (SEI) message is encoded indicating constraint related to a decoding process of the first tile set and the second tile set, and
• wherein the SEI message includes a top left tile index indicating a position of a top left tile included in a tile set.

A non-transitory computer readable storage medium storing a program to cause a computer to execute an image decoding method that decodes encoded data generated by performing hierarchical coding of images composing a moving image with a plurality of layers, the image decoding method comprising:

• decoding a SEI message indicating constraint related to a decoding process of a tile set composed of one or more tiles, the SEI message including a top left tile index indicating a position of a top left tile included in the tile set;
• and
• decoding a first tile set in a first image and a second tile set in a second image according to the SEI message, wherein the first image corresponds to a first layer and the second image corresponds to a second layer which is different from the first layer,
• wherein, in a case where the SEI message is decoded, the second tile set is arranged, in the second image, at a position corresponding to the first tile set,
• wherein the first tile set is decoded without reference to any tile set in the first image other than the first tile set, and decodes the second tile set without reference to any tile set in the second image other than the second tile set, and
• wherein, in a case where the SEI message is decoded and the first tile set is decoded with reference to at least apart of an area of the second image, the first tile set is decoded, without reference to any tile set in the second image other than the second tile set.