Patent ID: 7463686

Claim:
A motion vector and macroblock type determining method, the method comprising: receiving a high frame-rate video stream having N frames; skipping a frame N- 1 ; allocating a motion vector to a macroblock of frame N according to a macroblock type of the skipped frame N- 1 ; determining a macroblock type of the skipped frame N- 1 when the macroblock of the frame N is an intra type; allocating a macroblock type to a macroblock type of frame N according to a macroblock type of the skipped frame N- 1 ; wherein allocating the motion vector comprises: allocating an infinite motion vector to a macroblock of the frame N when the macroblock of the skipped frame N- 1 is an intra type; allocating a motion vector of the macroblock of the frame N when the macroblock of the skipped frame N- 1 is a skipped type; and allocating an approximated sum of the motion vector allocated to the macroblock of the frame N and the motion vector allocated to the macroblock of the frame N- 1 as a new motion vector for the macroblock of the frame N when the macroblock of the skipped frame N- 1 is an inter type; and outputting a low frame-rate video stream.