matlab - Combining Image Histograms -

matlab - Combining Image Histograms -

i want able create combined histogram of 3 grayness scaled images onto 1 histogram. when run code below, x axis overlaps each histogram have 3 identical x axes. want able have different colors signaling different pictures. here code:

subplot(4,3,1); image1=imread('93-94_1-0-32(302).png'); imshow(image1); gray1=rgb2gray(image1); subplot(4,3,2); image2=imread('90-91_1-0-32(101).png'); imshow(image2); gray2=rgb2gray(image2); subplot(4,3,3); image3=imread('55-56_1.2-0-18(sugar).png'); imshow(image3); gray3=rgb2gray(image3); subplot(4,3,[4,5,6]); imhist(gray1); hold on; imhist(gray2); hold on; imhist(gray3);

image matlab image-processing histogram matlab-figure