written 7.8 years ago by
teamques10
★ 64k
|
• modified 3.9 years ago |
| Grey levels | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|
| No of pixels | 100 | 90 | 50 | 20 | 0 | 0 | 0 | 0 |
|
written 7.8 years ago by
teamques10
★ 64k
|
Histogram Equalization Transformation function is defined as:
$S_k =\sum_{j=0}^k P_r r_j$
where $r_k$ and $s_k$ are normalized input and output gray values
| Input gray value | Normalized input | Frequency $N_{rk}$ | PDF $P_r = N_{rk}/N$ | CDF $S_k = \sum P_r$ | Output gray value,$S_k$(CDFx7) |
|---|---|---|---|---|---|
| 0 | 0 | 100 | 0.384 | 0.84 | 0.2688=3 |
| 1 | 1/7 | 90 | 0.346 | 0.73 | 5.11=5 |
| 2 | 2/7 | 50 | 0.192 | 0.922 | 6.944=7 |
| 3 | 3/7 | 20 | 0.077 | 1 | 7 |
| 4 | 4/7 | 0 | 0 | 1 | 7 |
| 5 | 5/7 | 0 | 0 | 1 | 7 |
| 6 | 6/7 | 0 | 0 | 1 | 7 |
| 7 | 1 | 0 | 0 | 1 | 7 |
| - | - | N = 260 | - | - | - |
Histogram of input image:
Histogram of output image:
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