COLOR CONTRAST ENHANCEMENT
ccenhance_cvip() - This function improves the color of the image.
Contents
SYNTAX
outputImage = ccenhance_cvip(InputImage, lowLimit, highLimit, lowClip, highClip);
Input Parameters include :
- InputImage - Input color image
- lowLimit - Lower limit for stretch
- highLimit - Higher limit for stretch
- lowClip - percentage of low values to clip before stretching
- highClip - percentage of high values to clip before stretching
Output Parameters include :
- outputImage - output image after color contrast enhancement.
DESCRIPTION
Color Contrast Enhance is an algorithm used to create brighter and better images. This function takes a color image as input. First, the function transforms the image to HSL color space and extracts the Hue, Saturation and Lightness bands. Then, it performs the histogram equalization on saturation band, which improves and intensifies the color richness. The lightness band is histogram stretched to improve the contrast. The HSL bands are then combined and inverse HSL transform is appplied. This function increases contrast in an image by stretching the histogram to span the range low_limit to high_limit.To improve performance of the function when outliers are present, percentage lowClip and highClip pixel values can be removed before the stretch takes place.
REFERENCE
1. Scott E Umbaugh. DIGITAL IMAGE PROCESSING AND ANALYSIS: Applications with MATLAB and CVIPtools, 3rd Edition.
EXAMPLE
% Read Image ipImage1=imread('butterfly.tif'); % Call function cceImage = ccenhance_cvip(ipImage1,0,255,0.025,0.025); % Display Input Image figure;imshow(ipImage1);title('Original RGB Image'); % Display Output Image figure;imshow(cceImage);title('Color Contrast Enhanced Image');
CREDITS
Author: Deependra Mishra, July 2017
Copyright © 2017-2018 Scott
E Umbaugh
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