Method and device to mark a reference picture for video coding

A video coding method, the method comprising:

• decoding, by a video coding apparatus, a current slice of a current picture to extract a reference picture set (RPS) from the current slice;
• determining, by the video coding apparatus, whether the current slice is a last slice of the current picture;
• marking, by the video coding apparatus, a reference picture in a decoded picture buffer (DPB) with a post-marking command after decoding the last slice of the current picture based on network abstraction layer (NAL) unit type;
• and
• performing an action on the DPB based on the NAL unit type,
• wherein the action comprises at least one of releasing a reference picture marked as unused for reference in the DPB, maintaining a reference picture marked as used for reference in the DPB, and releasing a co-located motion vector buffer associated with a reference picture marked as unused for reference in the DPB.

A video coding apparatus comprising:

• a memory configured to store computer-readable instructions;
• and
• a processor configured to execute the computer-readable instructions, which when executed cause the processor to implement functions of:
• a coding unit configured to:
• embed a pre-marking command and a post-marking command in a reference picture set (RPS) of a current picture;
• decode a current slice of a current picture to extract a reference picture set (RPS) from the current slice;
• determine whether the current slice is a last slice of the current picture;
• mark a reference picture in a decoded picture buffer (FRB) with a post-marking command based on a network abstraction layer (NAL) unit type;
• and
• perform an action on the DPB based on the NAL unit type,
• wherein the pre-marking is applied before decoding a current slice of the current picture and the post-marking is applied after decoding a last slice of the current picture, and
• wherein the action comprises at least one of releasing a reference picture marked as unused for reference in the DPB, maintaining a reference picture marked as used for reference in the DPB, and releasing a co-located motion vector buffer associated with a reference picture marked as unused for reference in the DPB.

A non-transitory computer-readable recording medium having embodied thereon executable program code, the computer executable program code when executed causes a video coding apparatus to execute a method of video coding, the method comprising:

• embedding a pre-marking command and a post-marking command in a reference picture set (RPS) for a current picture;
• decoding, by the video coding apparatus, the current slice of the current picture to extract the RPS from the current slice;
• determining, by the video coding apparatus, whether the current slice is a last slice of the current picture;
• marking, by the video coding apparatus, a reference picture in a decoded picture buffer (DPB) with the post-marking command based on a network abstraction layer (NAL) unit type;
• and
• performing an action on the DPB based on the NAL unit type,
• wherein the pre-marking is applied before decoding a current slice of the current picture and a post-marking is applied after decoding a last slice of the current picture, and
• wherein the action comprises at least one of releasing a reference picture marked as unused for reference in the DPB, maintaining a reference picture marked as used for reference in the DPB, and releasing a co-located motion vector buffer associated with a reference picture marked as unused for reference in the DPB.

A non-transitory computer-readable recording medium having embodied thereon computer executable program code, the computer executable program code when executed causes a video coding apparatus to execute a method of video coding, the method comprising:

• decoding a current slice of a current picture to extract a reference picture set (RPS) from the current slice;
• determining whether the current slice is a last slice of the current picture;
• marking a reference picture in a decoded picture buffer (DPB) with a post-marking command after decoding the last slice of the current picture based on network abstraction layer (NAL) unit type;
• and
• performing an action on the DPB based on the NAL unit type,
• wherein the action comprises at least one of releasing a reference picture marked as unused for reference in the DPB, maintaining a reference picture marked as used for reference in the DPB, and releasing a co-located motion vector buffer associated with a reference picture marked as unused for reference in the DPB.