imhist.q

This file contains routines for computing 1D and 2D histograms of images and performing histogram equalization.

Summary

imhist.q	This file contains routines for computing 1D and 2D histograms of images and performing histogram equalization.
Functions
imhist	Computes the histogram of an image
imjointhist	Computes the joint histogram of two images
imequalizehist	Performs histogram equalization

Computes the histogram of an image

function y = imhist(x, bins=256)

x	the input image
bins	either 1) the number of bins to be used, or 2) a vector containing the boundaries of the bins.
y	the output histogram (has size C x num_bins), where C is the number of color components of x, i.e. C = size(x,2)

Computes the joint histogram of two images

function h : mat = imjointhist(x, y, bins_x = 256, bins_y = 256)

x	input image #1
y	input image #2
bins_x	either 1) the number of bins to be used for x, or 2) a vector containing the boundaries of the bins of x.
bins_y	either 1) the number of bins to be used for y, or 2) a vector containing the boundaries of the bins of y.
h	a 2D joint histogram

Performs histogram equalization

function y = imequalizehist(x, mode = "yuv")

x	input image
mode	the histogram equalization mode

”rgb” - use histogram equalization in RGB space, where each color component is processed individually.
”grayscale” - histogram equalization of grayscale images. In case an RGB image is specified, the image is first converted to grayscale.
”yuv” - performs histogram equalization on the Y-channel of the input image.