Page 250 - Digital Analysis of Remotely Sensed Imagery

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DN (b) DN (d)
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10 8 6 4 Frequency (absolute) 2 0 100 80 60 40 20 Equalized cumulative probability 0 An example of histogram equalization of an image recorded at 4 bits. (a) Histogram of the raw image; (b) equalized histogram of the

16 16 output image; (c) cumulative relative frequency (%) of the input image; and (d) equalized cumulative frequency expressed in percentage. It is the decision rule in histogram equalization (e.g., whether pixels at a given DN level should b
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DN (a) DN (c)
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10 8 6 4 Frequency (absolute) 2 0 100 80 60 40 20 Cumulative frequency (%)

FIGURE 6.8

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