Page 272 - Digital Analysis of Remotely Sensed Imagery
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234    Cha pte r  S i x


                                           x − X
                                            i
           Pixel  Band 1   Band 2    Band 1   Band 2   Comp 1   Comp 2
           1      2        4         −3       −1        3.83     2.30
           2      4        5         −1        0        6.06     2.07
           3      3        6         −2        1        5.75     3.45
           4      4        3         −1       −2        4.99     0.38
           5      7        8          2        3       10.20     2.99
           6      7        6          2        1        9.13     1.30
           7      8        5          3        0        9.43    −0.08
           8      5        3          0       −2        5.83    −0.16
            X     5        5         −        −


          TABLE 6.2   Coordinates of the Eight Pixels in the Two Spectral Bands in Fig. 6.22




                               − ⎛ ⎧ 3 ⎞    − ⎛ ⎞1     − ⎛ 2 ⎞
                  V = 1/(8 − 1)  ⎜ ⎨  ⎟  (−3 − 1) +  ⎜ ⎟   (−1 0) +  ⎜  ⎟   (−2 1)
                             ⎩  − ⎝ 1 ⎠    ⎝ ⎠ 0       ⎝ 1 ⎠

                                              2 ⎛ ⎞
                                     2 ⎛ ⎞
                                                       3 ⎛ ⎞
                     +  ⎜ − ⎛ 1 ⎞ ⎟   (−1 − 2) +  ⎜ ⎟  (2 3) + ⎜ ⎟  (2 1) +  ⎜ ⎟  (3 0) +  ⎛ ⎜  0⎞ ⎟  (0 −2)
                        − ⎝ 2 ⎠      3 ⎝ ⎠    1 ⎝ ⎠    0 ⎝ ⎠     − ⎝  2⎠
                         ⎧⎛93 ⎞   ⎛ 10⎞   ⎛ 42⎞   ⎛ 12⎞
                   = 1/7  ⎨ ⎜  ⎟ + ⎜  ⎟ +  ⎜   ⎟  +  ⎜  ⎟
                         ⎩ ⎝39 ⎠  ⎝ 00⎠   ⎝ 21⎠   ⎝ 24⎠


                                                  ⎫
                       ⎛ 46⎞   ⎛ 42⎞  ⎛ 90⎞  ⎛ 00⎞⎫
                     +  ⎜ ⎝ 69⎠ ⎟  +  ⎜ ⎝ 21⎠ ⎟  + ⎜ ⎝ 00⎠ ⎟  +  ⎜ ⎝ 04⎠ ⎟ ⎬
                                                  ⎭
                         ⎛ 42 15⎞  ⎛  6   2 14⎞  ⎛ V  V ⎞
                                           .
                                                       12
                    = 1/7  ⎜ ⎝ 15 28⎠ ⎟  =  ⎜ ⎝ 214  4 ⎠ ⎟  =  ⎜ ⎝ V 11  V ⎠ ⎟ .
                                     .
                                                  21
                                                       22
                   After the variance-covariance matrix V is determined, it is time to
               calculate the correlation matrix R using Eq. (6.16):
                                     ⎡  1  r  ...  r ⎤
                                     ⎢    12      1n ⎥
                                 R = ⎢ r 21  1  ...  r 2n ⎥
                                     ⎢ ...  ...  ...  ... ⎥
                                      r ⎢  n ⎣ ⎣  1  r n 2  ...  1 ⎥ ⎦
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