Patent ID: 8630350

Claim:
A method of decoding an image sequence having a plurality of pictures, comprising: at a decoder, selectively decoding at least one of said plurality of pictures in a frame coding mode; and selectively decoding at least one of said plurality of pictures in a field coding mode, wherein a current field of a current picture in said field coding mode has at least one reference field, where each of said at least one reference field is assigned a unique reference field number, wherein said unique reference field number assigned to said at least one reference field is based upon a temporal distance between said at least one reference field and said current field and a field parity of said current field, wherein said current field is either a first field or a second field of said current picture, and wherein given said current field, a reference field that is of a same field parity as that of said current field is given a smaller unique reference field number relative to its corresponding other reference field of a same reference picture.