Changing the image contrast
Contrast stretch
This image is with the green enhancement
The cyan enhancement produces this image
Since temperatures of meteorological significance rarely exceed 40 º C or decrease below -80 º C, many of the
256 brightness values in the very warm and very cold temperature regions are wasted. A solution to this problem is to
assign a brightness value of zero (black) to all temperature values greater than 40 º C and assign a brightness value of
255 (white) to all temperature values less than -80 º C. The range of temperatures between -80 º C and 40 º C
will be represented by the 256 brightness values and thus will increase the slope of the diagonal. Representing a
smaller temperature range with 256 brightness values improves the contrast in the temperature range, allowing smaller
differences in temperature to be detected in the image. Thus this enhancement process is referred to as a contrast stretch.
Go back one step
Go back to front page
