Transmitting apparatus, transmission method, receiving apparatus, and reception method

A transmission method comprising:

• generating a base stream and an enhanced stream, the base stream including access units of encoded image data for each picture of basic-format image data, and the enhanced stream including access units of encoded image data for each picture of high-quality-format image data;
• and
• transmitting, by transmission circuitry, a container including the base stream and the enhanced stream, wherein
• the encoded image data for each picture of high-quality-format image data is obtained by performing a predictive coding process on the high-quality-format image data by referring to the basic-format image data and/or another high-quality-format image data, and
• information indicating a decoding order of the access units of the enhanced stream is added in an access unit delimiter placed at a beginning of each access unit in the enhanced stream, the added information indicating a same decoding order position as the access unit in the base stream that is associated with the respective access unit.

A receiving apparatus comprising:

• processing circuitry configured to
• receive a container, the container including a base stream and an enhanced stream, the base stream including access units of encoded image data for each picture of basic-format image data, and the enhanced stream including access units of encoded image data for each picture of high-quality-format image data;
• obtain basic-format image data or high-quality-format image data by processing the base stream, or the base stream and the enhanced stream;
• and
• decode the access units of the enhanced stream in an order based on information indicating a decoding order, wherein
• the encoded image data for each picture of high-quality-format image data is obtained by performing a predictive coding process on the high-quality-format image data by referring to the basic-format image data and/or another high-quality-format image data, and
• the information indicating the decoding order is added to each of the access units of the enhanced stream in an access unit delimiter placed at a beginning of each access unit of the enhanced stream, the added information indicating a same decoding order position as the access unit in the base stream that is associated with the respective access unit.

A reception method comprising:

• receiving, by a receiver, a container, the container including a base stream and an enhanced stream, the base stream including access units of encoded image data for each picture of basic-format image data, and the enhanced stream including access units of encoded image data for each picture of high-quality-format image data;
• obtaining basic-format image data or high-quality-format image data by decoding the base stream, or the base stream and the enhanced stream;
• and
• decoding the access units of the enhanced stream in an order based on information indicating a decoding order, wherein
• the encoded image data for each picture of high-quality-format image data is obtained by performing a predictive coding process on the high-quality-format image data by referring to the basic-format image data and/or another high-quality-format image data, and
• the information indicating the decoding order is added to each of the access units of the enhanced stream in an access unit delimiter placed at a beginning of each access unit of the enhanced stream, the added information indicating a same decoding order position as the access unit in the base stream that is associated with the respective access unit.