MATLAB Answers

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Local Binary Pattern(LBP)

Asked by C N N
on 13 Sep 2011
Latest activity Commented on by sajjad nasiri on 28 May 2019
I am trying to execute local binary pattern in MATLAB using the image processing toolbox. When i execute I can't get a LBP image and LBP histogram.
clear all;
close all;
clc;
I=imread('test.png');
figure,imshow(I)
%%Crop
I2 = imcrop(I);
figure, imshow(I2)
w=size(I2,1);
h=size(I2,2);
%%LBP
scale = 2.^[7 6 5; 0 -inf 4; 1 2 3];
for i=2:w-1
for j=2:h-1
J0=I2(i,j);
I3(i-1,j-1)=I2(i-1,j-1)>J0;
I3(i-1,j)=I2(i-1,j)>J0;
I3(i-1,j+1)=I2(i-1,j+1)>J0;
I3(i,j+1)=I2(i,j+1)>J0;
I3(i+1,j+1)=I2(i+1,j+1)>J0;
I3(i+1,j)=I2(i+1,j)>J0;
I3(i+1,j-1)=I2(i+1,j-1)>J0;
I3(i,j-1)=I2(i,j-1)>J0;
LBP(i,j)=I3(i-1,j-1)*2^7+I3(i-1,j)*2^6+I3(i-1,j+1)*2^5+I3(i,j+1)*2^4+I3(i+1,j+1)*2^3+I3(i+1,j)*2^2+I3(i+1,j-1)*2^1+I3(i,j-1)*2^0;
end
end
figure,imshow(LBP)
figure,imhist(LBP)
what is the issue.i am supposed to get numbers from 0 to 255 but i am not getting it. how to correct it?

  12 Comments

kalai selvi on 3 Feb 2018
i got hist try it thanks
Image Analyst
on 3 Feb 2019
Try
imshow(LBP, []);
and try my attached LBP demo.

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8 Answers

Answer by madhulika jain on 22 Sep 2011

I think you shpuld be getting LBP in the range 0 to 255. I ran this code and i got the values in this range only

  1 Comment

C N N
on 22 Sep 2011
The problem with this code that after you get LBP, you need to convert it to uint8 before displaying it.

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Izzo
Answer by Izzo
on 3 Dec 2011

hey i think i got your problem, because i already did LBP. First, make sure that u have converted the image into grayscale form. Second, you have to replace the test image with the new LBP image, therefore: instead of this code
LBP(i,j)=I3(i-1,j-1)*2^7+I3(i-1,j)*2^6+I3(i-1,j+1)*2^5+I3(i,j+1)*2^4+I3(i+1,j+1)*2^3+I3(i+1,j)*2^2+I3(i+1,j-1)*2^1+I3(i,j-1)*2^0;
try to change into:
I2(i-1,j-1)=I3(i-1,j-1)*2^7+I3(i-1,j)*2^6+I3(i-1,j+1)*2^5+I3(i,j+1)*2^4+I3(i+1,j+1)*2^3+I3(i+1,j)*2^2+I3(i+1,j-1)*2^1+I3(i,j-1)*2^0;
because i have problem like that too, then my supervisor solve into this for me :P

  1 Comment

elfrida
on 16 Aug 2013
sir, can you help me to make the program if i want to get LBP value from 13x13 image size?

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Image Analyst
Answer by Image Analyst
on 22 Sep 2011

Change the last few lines of your code to this:
subplot(2,2,3);
imshow(LBP, []);
subplot(2,2,4);
[pixelCounts, GLs] = imhist(uint8(LBP));
bar(GLs, pixelCounts);

  8 Comments

Image Analyst
on 28 Oct 2012
I almost always use [] because it scales the image so you can see it. For uint8 or binary (logical) images, it will automatically scale to 0-255 or 0-1 respectively. However for single or double images, you won't see anything unless you use [] OR your image has values only between 0.0 and 1.0. If you had a uint8 image that went, say, only from 0-42, then it would appear dark, but it you did [] it would map linearly from 0-42 into 0-255 so you'd be able to see it better. This is what imagesc() does except without the ridiculous colormap that imagesc() applies by default. However if you're visually comparing it to other uint8 images, you might want to use [0 255] instead of [].
By the way, I've posted full LBP demos here in the Answers forum and newsgroup before - you might want to look for it.
Aquib
on 31 Oct 2012
Thank you sir i really appreciate you help
Sir, it is possible for this LBP histogram to be an input of svm classification?. If possible, how we can convert this histogram into a vector for classification?

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remo
Answer by remo
on 1 Dec 2011

hi CNN,
Sorry for being a Noob. I just cant understand why you use 'scale = 2.^[7 6 5; 0 -inf 4; 1 2 3]; ' in this program. can you explain?

  7 Comments

C N N
on 18 Jan 2012
remo, u want to create a histogram is it? use a function called hist in MATLAB.
hi, I would like to know how did you get those number [ 7 6 5; 0 -inf 4; 1 2 3] ?
Did you calculate it?
Image Analyst
on 29 Mar 2019
Unhide the comments above and you'll see a desciption of how those are computed.

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Fa Fa
Answer by Fa Fa
on 13 Jun 2012

Hi All, has somebody the Result, i runed this code but i didnt get the result. Thanks

  0 Comments

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anusha
Answer by anusha
on 24 Sep 2014
Edited by anusha
on 24 Sep 2014

u can try this code
clear all; close all; I=imread('cameraman.tif'); I=rgb2gray(I); I1=imcrop(I); [w h]=size(I1);
for i=2:w-1 for j=2:h-1 val=I1(i,j); scale=2.^[0 1 2;7 -inf 3;6 5 4]; mat=[I1(i-1,j-1) I1(i-1,j) I1(i-1,j+1);I1(i,j-1) I1(i,j) I1(i,j+1);I1(i+1,j-1) I1(i+1,j) I1(i+1,j+1)]; mat=mat>=val; fin=mat.*scale; I1(i,j)=sum(sum(fin)); end end imshow(I1,[]);

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Answer by Nikolay S. on 16 Mar 2015

You can try one of the following LBP implementations: http://www.mathworks.com/matlabcentral/fileexchange/49787-shift-based-lbp http://www.mathworks.com/matlabcentral/fileexchange/36484-local-binary-patterns I'm using both for a while, updating them fomr time to time.

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Ktk
Answer by Ktk
on 29 Oct 2017

the code is not giving me any values. can anyone help? thanks!

  1 Comment

Image Analyst
on 30 Oct 2017
WHAT code?
Attached is my local binary pattern demo. Adapt as needed.

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