Figure 6-3.7
The first histogram shows values before equalization is performed. When this histogram is compared to the equalized histogram, one can see that the enhanced image gains contrast in the most populated areas of the original histogram. In this example, the input range of 3 to 7 is stretched to the range of 1 to 8. However, the data values at the tails of the original histogram are grouped together. Input values 0 through 2 all have the output values of 0. This results in the loss of the dark and bright characteristics usually associated with the tail pixels (ERDAS Inc. 1995)

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