# US 2020/0404304 A1 · Device and method for coding video data

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- Number: US 2020/0404304 A1
- Document ID: US20200404304A1
- Status: Published application
- Kind: A1
- Application number: 16/906,358
- Filed: 2020-06-19
- Published: 2020-12-24
- Earliest claimed: 2019-06-24
- Assignees: FG Innovation Company Limited
- Applicants: FG Innovation Company Limited
- Inventors: Chih-Yu Teng; Yu-Chiao Yang; Po-Han Lin
- Web page: https://patentgrep.com/patent/US20200404304A1

## CPC

- H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
- H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards
- 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
- H04N 19/119: Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
- H04N 19/176: the region being a block, e.g. a macroblock
- H04N 19/46: Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence)
- H04N 19/52: by predictive encoding
- H04N 19/543: using regions
- H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION

## Abstract

A method of decoding a bitstream by an electronic device is provided. A block unit is determined from an image frame received from the bitstream. First motion information having a first list flag for selecting a first reference frame and second motion information having a second list flag for selecting a second reference frame are received from a candidate list to reconstruct the block unit. A predefined one of the first and the second motion information is stored for a sub-block determined in the block unit without checking whether the first and second reference frames are included in a reference list indicated by a flag value different from the two list flags when the first list flag is identical to the second list flag. A following block is reconstructed based on the stored motion information when the following block is reconstructed based on the sub-block.

## Claims

### Claim 1

A method of decoding a bitstream by an electronic device, the method comprising:
receiving an image frame of the bitstream;
determining a block unit from the received image frame;
receiving first motion information and second motion information from a candidate list to reconstruct the block unit, wherein the first motion information includes a first list flag for selecting a first reference frame and the second motion information includes a second list flag for selecting a second reference frame;
determining a sub-block in the block unit;
comparing the first list flag with the second list flag;
storing a predefined one of the first motion information and the second motion information as a stored motion information for the sub-block without checking whether the first reference frame and the second reference frame are included in a specific one of a plurality of reference lists indicated by a specific one of a plurality of flag values different from the first list flag and the second list flag when the first list flag is identical to the second list flag; and
reconstructing a following block based on the stored motion information when the following block is reconstructed based on the sub-block.

### Claim 2 (depends on 1)

The method according to claim 1, further comprising:
determining a split line of the block unit; and
determining whether the sub-block is included in a specific one of a plurality of block regions separated based on the split line,
wherein the specific one of the plurality of block regions covers the split line, and
wherein the first list flag is compared with the second list flag when the sub-block is included in the specific one of the plurality of block regions.

### Claim 3 (depends on 2)

The method according to claim 2, further comprising:
storing the first motion information as the stored motion information for the sub-block when the sub-block is included in a first one of the plurality of block regions corresponding to the first motion information; and
storing the second motion information as the stored motion information for the sub-block when the sub-block is included in a second one of the plurality of block regions corresponding to the second motion information,
wherein each of the first one of the plurality of block regions and the second one of the plurality of block regions is different from the specific one of the plurality of block regions.

### Claim 4 (depends on 3)

The method according to claim 3, wherein the predefined one of the first motion information and the second motion information is the second motion information.

### Claim 5 (depends on 2)

The method according to claim 2, further comprising:
storing the predefined one of the first motion information and the second motion information as the stored motion information for the sub-block without checking whether the two reference frames are included in the specific one of the plurality of reference lists indicated by the specific one of the plurality of flag values different from the two list flags when the first list flag is identical to the second list flag and the sub-block is included in the specific one of the plurality of block regions; and
storing the first motion information and the second motion information together as the stored motion information for the sub-block when the first list flag is different from the second list flag and the sub-block is included in the specific one of the plurality of block regions.

### Claim 6 (depends on 1)

The method according to claim 1, wherein the specific one of the plurality of reference lists indicated by the specific one of the plurality of flag values is different from another one of the plurality of reference lists indicated by the first list flag when a number of the plurality of reference lists is equal to two and the first list flag is identical to the second list flag.

### Claim 7

An electronic device for decoding a bitstream, the electronic device comprising:
at least one processor; and
a storage device coupled to the at least one processor and storing a plurality of instructions which, when executed by the at least one processor, causes the at least one processor to:
receive an image frame of the bitstream;
determine a block unit from the received image frame;
receive first motion information and second motion information from a candidate list to reconstruct the block unit, wherein the first motion information includes a first list flag for selecting a first reference frame and the second motion information includes a second list flag for selecting a second reference frame;
determine a sub-block in the block unit;
compare the first list flag with the second list flag;
store a predefined one of the first motion information and the second motion information as the stored motion information for the sub-block without checking whether the first reference frame and the second reference frame are included in a specific one of a plurality of reference lists indicated by a specific one of a plurality of flag values different from the first list flag and the second list flag when the first list flag is identical to the second list flag; and
reconstruct a following block based on the stored motion information when the following block is reconstructed based on the sub-block.

### Claim 8 (depends on 7)

The electronic device according to claim 7, wherein the plurality of instructions, when executed by the at least one processor, further causes the at least one processor to:
determine a split line of the block unit; and
determine whether the sub-block is included in a specific one of a plurality of block regions separated based on the split line,
wherein the specific one of the plurality of block regions covers the split line, and
wherein the first list flag is compared with the second list flag when the sub-block is included in the specific one of the plurality of block regions.

### Claim 9 (depends on 8)

The electronic device according to claim 8, wherein the plurality of instructions, when executed by the at least one processor, further causes the at least one processor to:
store the first motion information as the stored motion information for the sub-block when the sub-block is included in a first one of the plurality of block regions corresponding to the first motion information; and
store the second motion information as the stored motion information for the sub-block when the sub-block is included in a second one of the plurality of block regions corresponding to the second motion information,
wherein each of the first one of the plurality of block regions and the second one of the plurality of block regions is different from the specific one of the plurality of block regions.

### Claim 10 (depends on 9)

The electronic device according to claim 9, wherein the predefined one of the first motion information and the second motion information is the second motion information.

### Claim 11 (depends on 8)

The electronic device according to claim 8, wherein the plurality of instructions, when executed by the at least one processor, further causes the at least one processor to:
store the predefined one of the first motion information and the second motion information as the stored motion information for the sub-block without checking whether the two reference frames are included in the specific one of the plurality of reference lists indicated by the specific one of the plurality of flag values different from the two list flags when the first list flag is identical to the second list flag and the sub-block is included in the specific one of the plurality of block regions; and
store the first motion information and the second motion information together as the stored motion information for the sub-block when the first list flag is different from the second list flag and the sub-block is included in the specific one of the plurality of block regions.

### Claim 12

A method of decoding a bitstream by an electronic device, the method comprising:
receiving an image frame of the bitstream;
determining a block unit from the received image frame;
determining a split line of the block unit;
receiving first motion information and second motion information from a candidate list to reconstruct the block unit, wherein the first motion information includes a first list flag and the second motion information includes a second list flag;
determining a sub-block in the block unit;
determining whether the sub-block is included in a specific one of a plurality of block regions separated based on the split line, wherein the specific one of the plurality of block regions covers the split line;
determining, based only on a comparison between the first list flag and the second list flag, whether the first motion information and the second motion information are stored together as the stored motion information for the sub-block, when the sub-block is included in the specific one of the plurality of block regions; and
reconstructing a following block based on the stored motion information when the following block is reconstructed based on the sub-block.

### Claim 13 (depends on 12)

The method according to claim 12, further comprising:
storing the first motion information as the stored motion information for the sub-block when the sub-block is included in a first one of the plurality of block regions corresponding to the first motion information; and
storing the second motion information as the stored motion information for the sub-block when the sub-block is included in a second one of the plurality of block regions corresponding to the second motion information,
wherein each of the first one of the plurality of block regions and the second one of the plurality of block regions is different from the specific one of the plurality of block regions.

### Claim 14 (depends on 13)

The method according to claim 13, further comprising:
storing the second motion information as the stored motion information for the sub-block when the first list flag is equal to the second list flag and the sub-block is included in the specific one of the plurality of block regions.

### Claim 15 (depends on 12)

The method according to claim 12, wherein the block unit is reconstructed prior to reconstructing the following block.

### Claim 16 (depends on 12)

The method according to claim 12, further comprising:
storing the first motion information and the second motion information together as the stored motion information for the sub-block when the first list flag is different from the second list flag.

### Claim 17 (depends on 12)

The method according to claim 12, wherein a predefined one of the first motion information and the second motion information is stored as the stored motion information for the sub-block without checking whether a first reference frame selected based on the first list flag and a second reference frame selected based on the second list flag are included in a specific one of a plurality of reference lists indicated by a specific one of a plurality of flag values different from the first list flag when the first list flag is equal to the second list flag.