Transmission device, transmission method, reception device, and reception method

A reception device comprising:

• processing circuitry configured to
• receive a video stream that includes, for each of a plurality of units of N consecutive pictures of a plurality of pictures, an encoded averaged picture and encoded N−1 of the N consecutive pictures of the respective unit, the averaged picture being generated based on an averaging process in which a non-linear average of the N consecutive pictures of the respective unit is calculated with different gains, the video stream including a first sub-layer having the encoded averaged pictures and a second sub-layer having the encoded N−1 pictures of the plurality of units,
• receive information including averaging process information indicating a method for the averaging process, and
• process the received video stream in accordance with the averaging process information,
• wherein the information further includes identification information indicating existence of the averaging process information in the information.

A reception method comprising:

• receiving a video stream that includes, for each of a plurality of units of N consecutive pictures of a plurality of pictures, an encoded averaged picture and encoded N−1 of the consecutive pictures of the respective unit, the averaged picture being generated based on an averaging process in which a non-linear average of the N consecutive pictures of the respective unit is calculated with different gains, the video stream including a first sub-layer having the encoded averaged pictures and a second sub-layer having the encoded N−1 pictures of the plurality of units;
• receiving information including averaging process information indicating a method for the averaging process;
• and
• processing, by processing circuitry of a reception device, the received video stream in accordance with the averaging process information,
• wherein the information further includes identification information indicating existence of the averaging process information in the information.