Patent ID: 7145951

Claim:
A motion estimation method used in a video compression system, the video compression system divides a current picture into a plurality of blocks, the method comprising: stepping through a plurality of candidate motion vectors (x, y) in a search range for a current encoding block in the current picture, wherein the current encoding block includes (i 1 −i 0 )*(j 1 −j 0 ) pixels; calculating a cost function for each candidate motion vector (x, y) as follows, wherein Cij is a pixel in the current encoding block, Pi+x,j+y is a pixel in the search range of a target picture, and Qp is a quantization step: CF ⁡ ( x , y ) = ∑ i = i0 i1 ⁢ ⁢ ∑ j = j0 j1 ⁢ {  C i , j - P i + x , j + y  + h ⁡ ( Q ⁢ ⁢ p , C i , j , P i + x , j + y ) } ; and determining the candidate motion vector (x, y) in the search range that minimizes the cost function to be an optimal motion vector (x 1 , y 1 ) of the current encoding block.