Encoding device and encoding method with setting and encoding of reference information

Patent metadata

Field	Value
Publication number	US-11399197-B2
Application number	US-202117170744-A
Country	US
Kind code	B2
Filing date	Feb 8, 2021
Priority date	Jun 29, 2012
Publication date	Jul 26, 2022
Grant date	Jul 26, 2022

Abstract

The present technology relates to an encoding device and an encoding method capable of reducing the amount of information relating to information that specifies a reference image.An encoding unit generates a predicted image using a reference image. A transmission unit transmits inter_ref_pic_set_prediction_flag representing whether reference image specifying information specifying the reference image of a prior image that is an image prior to a current coding image in coding order is used as the reference image specifying information of the current coding image in a case where the current coding image is an image other than a first image of a GOP (Group of Picture). The present technology, for example, can be applied to an encoding device of an HEVC (High Efficiency Video Coding) system.

First claim

The invention claimed is:

1. A decoding device comprising:
circuitry configured to:
decode a syntax element from a sequence parameter set (SPS) for a plurality of pictures to be decoded, the syntax element indicating a number of short-term reference picture sets (short-term RPS) included in the SPS;
determine a value for an index of a short-term RPS of the current picture based on the number of short-term RPS indicated by the syntax element from the SPS, the current picture being a picture from the plurality of pictures;
in a case where the value of the index of the short-term RPS for the current picture is not equal to zero:
decode a reference picture set prediction flag (RPS prediction flag), wherein the value of the RPS prediction flag is decoded to be either:
a first value indicating that one of the short-term RPS included in the SPS, where the SPS precedes the current picture, is used to predict a short-term RPS for the current picture,
or
a second value indicating that none of the short-term RPS included in the SPS are used to predict the short-term RPS for the current picture, and, that the short-term RPS for the current picture is in a slice header of the current picture; and

in a case where the value of the index of the short-term RPS for the current picture is equal to zero:
decode, from the slice header of the current picture, the short-term RPS for the current picture;

wherein the short-term RPS for the current picture comprises information specifying a reference picture set used to generate a prediction picture for the current picture.

2. The decoding device according to claim 1 ,
wherein the circuitry is further configured to,
in the case where the value of the index of the short-term RPS for the current picture is not equal to zero, based on the value of the RPS prediction flag being set to the first value indicating that one of the short-term RPS included in the SPS is used to predict the short-term RPS of the current picture:
decode a delta index value identifying the one short-term RPS included in the SPS used to predict the short-term RPS of the current picture.

3. A decoding method comprising:
decoding a syntax element from a sequence parameter set (SPS) for a plurality of pictures to be decoded, the syntax element indicating a number of short-term reference picture sets (short-term RPS) included in the SPS;
determining a value for an index of a short-term RPS of the current picture based on the number of short-term RPS indicated by the syntax element from the SPS, the current picture being a picture from the plurality of pictures;
in a case where the value of the index of the short-term RPS for the current picture is not equal to zero:
decoding a reference picture set prediction flag (RPS prediction flag), wherein the value of the RPS prediction flag is decoded to be either:
a first value indicating that one of the short-term RPS included in the SPS, where the SPS precedes the current picture, is used to predict a short-term RPS for the current picture,
or
a second value indicating that none of the short-term RPS included in the SPS are used to predict the short-term RPS for the current picture, and, that the short-term RPS for the current picture is in a slice header of the current picture; and

in a case where the value of the index of the short-term RPS for the current picture is equal to zero:
decoding, from the slice header of the current picture, the short-term RPS for the current picture;

wherein the short-term RPS for the current picture comprises information specifying a reference picture set used to generate a prediction picture for the current picture.

4. The decoding method according to claim 3 , further comprising, in the case when the index of the short-term RPS of the current picture is not equal to zero, based on the value of the RPS prediction flag being set to the first value indicating that one of the short-term RPS included in the SPS is used to predict the short-term RPS of the current picture:
decoding a delta index value identifying the short-term RPS included in the SPS used to predict the short-term RPS of the current picture.

Assignees

• Velos Media Llc

Inventors

• Lu Shuo
• Sato Kazushi

Classifications

• H04N19/577

  Motion compensation with bidirectional frame interpolation, i.e. using B-pictures · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/52 Primary

  by predictive encoding · CPC title

• H04N19/105 Primary

  Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction · CPC title

• H04N19/109

  among a plurality of temporal predictive coding modes · CPC title