Direct Histogram Specify (continued)
Figure( 5. 9) |
To obtain the z levels we apply the inverse of G transform obtained, to the histogram equalized levels  .
Since we are dealing with inverse values an approximation must be made in the inverse mapping. For example the closest match to  is  or using the inverse  .
Thus  is mapped to level  .Using this procedure yields the following mappings for
These results can be combined with those of histogram equalization to yield the following direct mappings
Redistributing the pixels according to these mappings and dividing by n =4096 results in the histogram
Figure( 5.10) |
Resulting histogram is not particularly close to the desired shape. Error decreases as no of levels increases.
|
|
|
|
0 |
0 |
|
0 |
0 |
|
0 |
0 |
|
790 |
0.19 |
|
1023 |
0.25 |
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850 |
0.21 |
|
985 |
0.24 |
|
448 |
0.11 |
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