$$C（k，l）＝{\displaystyle \underset{米＝0}{\overset{米-1}{\sum }}{\displaystyle \underset{n＝0}{\overset{N-1}{\sum }}我1（米，n）\overline{我2}}（米+k，n+l）．}$$

$$\begin{array}{l}{C}_N（k，l）＝\frac{{\displaystyle \underset{米＝0}{\overset{米-1}{\sum }}{\displaystyle \underset{n＝0}{\overset{N-1}{\sum }}我1（米，n）\overline{我2}}（米+k，n+l）}}{\sqrt{{\displaystyle \underset{米＝0}{\overset{米-1}{\sum }}{\displaystyle \underset{n＝0}{\overset{N-1}{\sum }}我1{（米，n）}^2}}}\sqrt{{\displaystyle \underset{米＝0}{\overset{米-1}{\sum }}{\displaystyle \underset{n＝0}{\overset{N-1}{\sum }}\overline{我2}{（米+k，n+l）}^2}}}}，\\ \text{在那里,}\\ 0\le k<米+P-1\\ 0\le l<N+问-1\end{array}$$

$$\frac{585}{\sqrt{{\displaystyle \sum 我1_p^2}}\sqrt{{\displaystyle \sum 我2^2}}}＝\mathrm{0.8070.}$$