Method for reference picture processing in video coding

A method of encoding a video sequence into a bitstream, the method comprising:

• receiving a video sequence;
• and
• encoding one or more pictures of the video sequence;
• wherein the encoding comprises:
• signaling a first flag in a slice header to indicate whether an active reference index number is present in a slice header, wherein the active reference index number is used to derive maximum reference index for a corresponding reference picture list that is used to encode a current slice;
• in response to the first flag indicating that the active reference index number is present in the slice header,
• determining a number of entries of reference picture list 0, and signaling an active reference index number of reference picture list 0 in the slice header for P and B slices when the number of entries of reference picture list 0 is greater than 1;
• and
• determining a number of entries of reference picture list 1, and signaling an active reference index number of reference picture list 1 in the slice header for B slice when the number of entries of reference picture list 1 is greater than 1.

A method of decoding a bitstream to output one or more pictures for a video stream, the method comprising:

• receiving a bitstream;
• and
• decoding, using coded information of the bitstream, one or more pictures, wherein the decoding comprises:
• determining, in a slice header, a value of a first flag indicating whether an active reference index number is present, wherein the active reference index number is used to derive maximum reference index for a corresponding reference picture list that may be used to decode a current slice;
• in response to the first flag indicating that the active reference index number is present, determining a number of entries of reference picture list 0 and a number of entries of reference picture list 1;
• decoding an active reference index number of reference picture list 0 in the slice header for P and B slices, when the number of entries of reference picture list 0 is greater than 1;
• and
• decoding an active reference index number of reference picture list 1 in the slice header for B slice, when the number of entries of reference picture list 1 is greater than 1.

A non-transitory computer-readable storage medium storing a bitstream comprising coded information for decoding one or more pictures, wherein the bitstream comprises:

• a first flag indicating whether an active reference index number is present, the active reference index number being used to derive maximum reference index for a corresponding reference picture list for decoding a current slice, wherein:
• when the first flag indicates that the active reference index number is present, a number of entries of reference picture list 0 and a number of entries of reference picture list 1 are determined;
• when the number of entries of reference picture list 0 is greater than 1, an active reference index number of reference picture list 0 in the slice header for P and B slices is decoded;
• and
• when the number of entries of reference picture list 1 is greater than 1, an active reference index number of reference picture list 1 in the slice header for B slice is decoded.