Patent ID: 6175593
Filing Date: 2001-01-16
Classification: H04N

Abstract:
A method for estimating a motion vector in a moving picture, the method comprising the steps of:estimating motions for luminance components of a plurality of macroblocks;determining a coding prediction mode when a motion vector is obtained;searching blocks of which coding prediction mode is determined to be a first mode for halfpels;selecting an initial motion vector from one of motion vectors obtained by a bilinear interpolation of a macroblock motion vector and motion vectors of blocks adjacent the macroblock;making a first search of the initial motion vectors of the blocks in a search region when the initial vectors of the blocks are determined; andmaking second search to obtain final motion vectors and using the final motion vectors to predict one of a motion in block units and a motion in macroblock units, wherein after the final motion vector is obtained, further comprising estimating and compensating the motion vector by comparing a sum of the Summation Absolute Differentials (SADs) (SAD.sup.i.sub.8,1.ltoreq.i.ltoreq.4) from the 4 8.times.8 blocks, and the SAD (SAD.sub.16) from MV.sub.16 and predicting a motion in 16.times.16 block units unless the motion is predicted in 8.times.8 block units using the 4 8.times.8 motion vectors because the comparison satisfies the following condition: ##EQU4##where N.sub.B is the number of pixels in a macroblock.