Image coding method, image coding apparatus, image decoding method, image decoding apparatus, and image coding and decoding apparatus

• US 11,115,664 B2
• Filed: 05/26/2020
• Issued: 09/07/2021
• Est. Priority Date: 05/27/2011
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Sun Patent Trust
• Inventors: Sugio, Toshiyasu, Nishi, Takahiro, Shibahara, Youji, Tanikawa, Kyoko, Sasai, Hisao, Matsunobu, Toru
• Primary Examiner(s): Holder, Anner N
• Application Number:
  US16/882,872
• Publication Number:
  US 20200288142A1
• Time in Patent Office: 469 Days
• CPC Class Codes: H04N 19/102 characterised by the element, parameter or selection affected or controlled by the adaptive coding
• CPC Class Codes: H04N 19/105 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 Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/134 characterised by the element, parameter or criterion affecting or controlling the adaptive coding
• CPC Class Codes: H04N 19/139 Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/184 the unit being bits, e.g. of the compressed video stream
• CPC Class Codes: H04N 19/197 including determination of the initial value of an encoding parameter H04N19/56 takes precedence
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/52 by predictive encoding
• CPC Class Codes: H04N 19/577 Motion compensation with bidirectional frame interpolation, i.e. using B-pictures
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards

Abstract

A moving picture coding apparatus, method, and medium for coding a current block are provided. A first candidate is derived from a first motion vector that has been used to decode a first block. The first block is adjacent to the current block. A first index identifying a reference picture to be selected for coding the current block is coded. A second candidate having a second motion vector that includes a non-zero value is derived. The non-zero value is assigned to the reference picture. A selected candidate is selected from a plurality of candidates, including the first candidate and the second candidate. A second index identifying the selected candidate is coded. The current block is coded using the selected candidate. The second candidate includes the non-zero value of the reference picture, with the reference picture being selected from a plurality of referable reference pictures.

Claims

1. A moving picture coding apparatus for coding a current block, the moving picture coding apparatus comprising:

a processor; and

a non-transitory memory,

wherein the processor performs, using the non-transitory memory, processes including;

deriving a first candidate from a first motion vector that has been used to code a first block, the first block being adjacent to the current block;

coding a first index identifying a reference picture selected for coding the current block;

deriving a second candidate having a second motion vector that includes a non-zero value, the non-zero value assigned to the reference picture;

selecting a selected candidate to be used for coding the current block from a plurality of candidates, the plurality of candidates including the first candidate and the second candidate;

coding a second index identifying the selected candidate; and

coding the current block using the selected candidate, and

the second candidate includes the non-zero value of the reference picture, the reference picture being selected from a plurality of referable reference pictures based on the first index.

2. The moving picture coding apparatus according to claim 1, wherein

different offset values are assigned as non-zero values for the plurality of referable reference pictures.

3. The moving picture coding apparatus according to claim 2, wherein

each of the non-zero values for the plurality of referable reference pictures includes an x-axis offset value and a y-axis offset value.

4. A moving picture coding method for coding a current block, the moving picture coding method comprising:

deriving a first candidate from a first motion vector that has been used to code a first block, the first block being adjacent to the current block;

coding a first index identifying a reference picture selected for coding the current block;

deriving a second candidate having a second motion vector that includes a non-zero value, the non-zero value assigned to the reference picture;

selecting a selected candidate to be used for coding the current block from a plurality of candidates, the plurality of candidates including the first candidate and the second candidate;

coding a second index identifying the selected candidate; and

coding the current block using the selected candidate,

wherein the second candidate includes the non-zero value of the reference picture, the reference picture being selected from a plurality of referable reference pictures based on the first index.

5. The moving picture coding method according to claim 4, wherein

different offset values are assigned as non-zero values for the plurality of referable reference pictures.

6. The moving picture coding method according to claim 5, wherein

each of the non-zero values for the plurality of referable reference pictures includes an x-axis offset value and a y-axis offset value.

7. A non-transitory computer-readable medium including a program for coding a current block, the program, when executed by a processor, causing the processor to perform processes, the processes comprising:

deriving a first candidate from a first motion vector that has been used to code a first block, the first block being adjacent to the current block;

coding a first index identifying a reference picture selected for coding the current block;

deriving a second candidate having a second motion vector that includes a non-zero value, the non-zero value assigned to the reference picture;

selecting a selected candidate to be used for coding the current block from a plurality of candidates, the plurality of candidates including the first candidate and the second candidate;

coding a second index identifying the selected candidate; and

coding the current block using the selected candidate,

wherein the second candidate includes the non-zero value of the reference picture, the reference picture being selected from a plurality of referable reference pictures based on the first index.

8. The non-transitory computer-readable medium according to claim 7, wherein

different offset values are assigned as non-zero values for the plurality of referable reference pictures.

9. The non-transitory computer-readable medium according to claim 8, wherein

each of the non-zero values for the plurality of referable reference pictures includes an x-axis offset value and a y-axis offset value.