MATLAB CVIP Toolbox Functions

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The histogram category allows the user to perform standard histogram modification techniques for image enhancement such has histogram equalization, stretching, sliding, specification, linear mapping and local equalization. The unsharp masking sharpening algorithm is also included here since it is an enhancement method that uses both a histogram shrink and stretch. For histogram equalization with color images, the user can specify which of the red, green, or blue bands to base the equalization on. To recreate the functionality in CVIPtools, which allows the user to perform histogram equalization on the lightness, or L band, of an HSL transformed image, the CVIP Toolbox functions can be used. This is accomplished by this sequence: 1) perform the HSL color transform, 2) extract the L, or third, band from the image, 3) perform histogram equalization on the L band, 4) assemble the color image with the H, S and the histogram equalized L, bands, 5) perform the inverse HSL color transform on the result.