Implement Histogram Equalisation without Histeq( )

[@robb1324]

In the line: sum = sum + freq(i) "freq" is not a function. I'm not sure how it worked on your matlab. :(

[@visintel]

She later on changed Freq to f

[@oumaymayousfi9811]

hi rachi, i have a question , i implement your programm but it''s not working ..when i execute the programm . the result was just a black picture .. plz can you help me .. i really need to this programm to work .. thanks

[@_tinker_bell]

yeah...for me too...can anyone help??

[@Earth4Mars]

Thx. I have a question. How can I apply histogram equalization on a selected range.
I want to apply HE on 3 ranges on the images. 0 to 10 then 11 to 180 then 181 to 255?

[@emreyonet7262]

Is there local histogram equalization without hiteq ? Please help.

[@khitemamiri8051]

Hi rashi, thank you for your explanation, i would like to ask please, how can i assign a function (that change the intensity) to the pixels with intensity values between 0 and 127 for example and another equation to the pixels from 128 to 255 ??

[@alexanderroman7650]

Thank to you miss, you have save a soul jajjaja. Greetings for latam

[@alexanderroman7650]

also, if someone needs the code, its here. (Hope you dont mind miss rashi)
clc, clear all
a=imread('Name of you image.extension');
r=size(a,1);
c=size(a,2);
ah=uint8(zeros(r,c));
n=r*c;
f=zeros(256,1);
pdf=zeros(256,1);
cdf=zeros(256,1);
cum=zeros(256,1);
out=zeros(256,1);
for i=1:r
for j=1:c
value = a(i,j);
f(value+1)=f(value+1)+1;
pdf(value+1)=f(value+1)/n;
end
end
sum=0; L=255
for i=1:size(pdf)
sum = sum + f(i);
cum(i) = sum;
cdf(i) = cum(i)/n;
out(i) = round(cdf(i)*L)
end
for i=1:r
for j=1:c
ah(i,j)=out(a(i,j)+1);
end
end
figure()
subplot(2,1,1)
imshow(ah)
subplot(2,1,2)
imshow(histeq(a))

[@youngresearcher.]

Happy to help

[@devilboii96]

Can I ask how do you find gray level? I have a gray image that has pixel intensities from 0-255 so is the gray level from 0-255?

[@vinaypant569]

where this freq came from? you havent declared it and still this program is running?

[@darksideofthemoon3185]

thank you so much you're my savior!

[@ramanchopra6772]

Can you tell me how to prepare median filter using matlab simulink or prepare a tutorial for it asap

[@arunpillai1685]

Can u plot the histogram as well ?

[@wedsonbarbosa9027]

Thank you!! It was a great explanation

[@mohamedouahidi57]

please how do Local Histogram Equalisation

[@marioserodotou2958]

thanks mam! very good explanation!

[@동반입대]

hi rashi, i'm korean student.
I have a question in your code.what is f? T_T Is that function?? else,, just variable???
plz help me T_T

[@vinaypant569]

variable

[@umutdonmez2707]

ty so much . i used my homework.

[@darknightr15yzf]

u saved me thanks a lot

[@gvalchca1]

hi rashi, thanx for the great explanation :)

[@youngresearcher.]

Thanks :)

[@shashanksingh2727]

srry ma'am but theory isn't that much clear after lecture 14

[@oshanadissanayake7884]

will this be the answer to the question
Write a program which will apply histogram equalization to a 256 level gray scale image.
You can only use imread function in matlab.
Program should accept an image of any size.

[@arunpillai1685]

Wtf is freq(i) ?

[@Sanaullah-be3rd]

define freq= histogram(image); it will work

[@rizwankhalid9266]

nice

[@sakib8275]

anyone having problem with sum = sum + freq(i); change freq(i) to f(i). it will work

[@vinaypant569]

this program executes a black pic

[@qamarabbas9196]

Thanks Bro its work....

[@muhammadfaique9978]

Not working this code is even wrong what the fuck