f ( i , j ) = ∑ u = − l l ∑ v = − k k [ w ( u , v ) − w ˉ ] [ f ( i + u , j + v ) − f ˉ ] { ∑ u = − l l ∑ v = − k k [ w ( u , v ) − w ˉ ] 2 ∑ u = − l l ∑ v = − k k [ f ( i + u , j + v ) − f ˉ ] 2 } 1 2 f(i,j) = \frac{\sum\limits_{u = -l}^{l}\sum\limits_{v = -k}^{k}[w(u,v)-\bar{w}][f(i+u,j+v) - \bar{f}]}{\{\sum\limits_{u = -l}^{l}\sum\limits_{v = -k}^{k}[w(u,v)-\bar{w}]^2\sum\limits_{u = -l}^{l}\sum\limits_{v = -k}^{k}[f(i+u,j+v) - \bar{f}]^2\}^{\frac{1}{2}}} f(i,j)={u=−l∑lv=−k∑k[w(u,v)−wˉ]2u=−l∑lv=−k∑k[f(i+u,j+v)−fˉ]2}21u=−l∑lv=−k∑k[w(u,v)−wˉ][f(i+u,j+v)−fˉ]