Patent ID: 7835448

Claim:
A method of decoding a current field block by selecting a reference field picture performed by a moving picture decoder, comprising: obtaining, by the moving picture decoder, a reference frame picture list of multiple reference frame pictures; determining, by the moving picture decoder, a reference frame picture index based on display order information for the multiple reference frame pictures; obtaining, by the moving picture decoder, a reference field picture index associated with the current field block; determining, by the moving picture decoder, a reference frame picture from the multiple reference frame pictures included in the reference frame picture list based on the obtained reference field picture index divided by 2; selecting, by the moving picture decoder, a reference field picture having a different parity from the current field block if the obtained reference field picture index is an odd value, otherwise the selecting step selects a reference field picture having a same field parity as the current field block; and decoding, by the moving picture decoder, the current field block by referring to the selected reference field picture.