A method of decoding video, comprising: decoding a current direct-mode one motion vector (1 MV) macroblock in a current interlaced bi-directionally predicted field, including: determining that a co-located macroblock in a temporally future interlaced predicted field was encoded using four-motion-vector encoding; determining one or more motion vectors of the co-located macroblock; and calculating a motion vector to use in direct mode scaling operations for the current direct-mode one motion vector (1 MV) macroblock by: determining whether more of the one or more motion vectors of the co-located macroblock reference a first reference field of a first field polarity or a second reference field of a second field polarity; if more of the one or more motion vectors of the co-located macroblock reference the second reference field, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the second reference field; and otherwise, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the first reference field; and reconstructing the current interlaced bi-directionally predicted field using the decoded current direct-mode macroblock. decoding a current direct-mode one motion vector (1 MV) macroblock in a current interlaced bi-directionally predicted field, including: determining that a co-located macroblock in a temporally future interlaced predicted field was encoded using four-motion-vector encoding; determining one or more motion vectors of the co-located macroblock; and calculating a motion vector to use in direct mode scaling operations for the current direct-mode one motion vector (1 MV) macroblock by: determining whether more of the one or more motion vectors of the co-located macroblock reference a first reference field of a first field polarity or a second reference field of a second field polarity; if more of the one or more motion vectors of the co-located macroblock reference the second reference field, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the second reference field; and otherwise, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the first reference field; and determining that a co-located macroblock in a temporally future interlaced predicted field was encoded using four-motion-vector encoding; determining one or more motion vectors of the co-located macroblock; and calculating a motion vector to use in direct mode scaling operations for the current direct-mode one motion vector (1 MV) macroblock by: determining whether more of the one or more motion vectors of the co-located macroblock reference a first reference field of a first field polarity or a second reference field of a second field polarity; if more of the one or more motion vectors of the co-located macroblock reference the second reference field, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the second reference field; and otherwise, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the first reference field; and determining whether more of the one or more motion vectors of the co-located macroblock reference a first reference field of a first field polarity or a second reference field of a second field polarity; if more of the one or more motion vectors of the co-located macroblock reference the second reference field, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the second reference field; and otherwise, computing the motion vector to use in direct mode scaling operations using only those of the one or more motion vectors of the co-located macroblock that reference the first reference field; and reconstructing the current interlaced bi-directionally predicted field using the decoded current direct-mode macroblock.