lab2_other

Lab 2
Read the image
Generate the Lab image
Split the 3D image into seperate channels
Display the image histogram
Select the colour
Morphological operators

Lab 2

Lab space colour segmentation examples

close all  %close all figures
clear  %clear varibles

Read the image

Read the image and convert to type double. Use the readDoubleImage function from last week. Note that Matlab lets us read images from websites so we can do this rather than download it first!

url = 'http://blogs.mathworks.com/images/steve/2010/mms.jpg';
rgb = readDoubleImage(url);
imshow(rgb)

Generate the Lab image

lab = applycform(rgb, makecform('srgb2lab'));
lab = lab2double(lab);

Split the 3D image into seperate channels

a = lab(:,:,2);
b = lab(:,:,3);

Display the image histogram

LabHistPlot(a,b);

Select the colour

By zooming in, find the bounadries for one of the blobs use this to segment the image

amin=-71;
amax=-50;
bmin=55;
bmax=75;
in = inpolygon(a, b, [amin,amax], [bmin bmax]);
figure(3)
imshow(in)

Morphological operators

Now lets clean the segmentation mask by removing the holes with dilation and erode

figure(4)
im2=imdilate(in,ones(7));
im3=imerode(im2,ones(7));
imshow(im3)

% Or I could have used imfill
figure(5)
im4=imfill(in,'holes');


imshow(im4)
% Or some other mixture
figure(6)
im5=imdilate(in,ones(7));
im5=imerode(im5,ones(7));
im5=imfill(im5,'holes');
imshow(im5)