Computing the sum of each column in an image

Hi i want to find out the sum of individual columns in an image and draw a plot indicating the number of pixels in each column(A density chart).Here is my code. Please help me further.

CODE:

clc;clear all,close all;
newimage=imread('NEW1.jpg');
count=find(newimage<1);
disp(count);
sum1=sum(newimage');
display(sum1);

OUTPUT:

sum1 =

    Columns 1 through 5

         69646       69446       18233       68154       57611

    Columns 6 through 10

         45726       36549       54894       20902        3878

    Columns 11 through 15

         45726        .......

BUT I WANT MY OUTPUT TO BE AS

 4512(say)[sum for the first column]  4561[for the second column] and so on....

HOW TO GET IT??? PLEASE HELP

[Walter Roberson]

This question appears to be a duplicate (with some rephrasing) of the posters earlier question http://www.mathworks.com/matlabcentral/answers/255-creating-a-plot-of-intensity-of-pixels-across-an-image-using-matlab

[Niranjan]

ya its me who asked it earlier,but now in detail :)

[Kenneth Eaton]

Niranjan, you should be able to edit the original question to add more detail, which would be better than reasking it.

[Niranjan]

bar(avg(newimage<1)) when I use the above code I get a bar . But I need a bar with the number of black pixels on the y axis. Can you help?

This is what I am exactly in need of. Please have a look.

http://picasaweb.google.com/lh/photo/uzVPD9_OcmXMtPGw4m0jyJOzMXS1UfqXPDW9N1lFu0w?feat=directlink

[Walter Roberson]

duplicates http://www.mathworks.com/matlabcentral/answers/255-creating-a-plot-of-intensity-of-pixels-across-an-image-using-matlab

[Sampath Kumar]

bar(mean(~im))

Answer 1

[Walter Roberson]

The number of pixels in each column of an image is a constant. If you only want to count the number of pixels below a certain value, then:

bar(mean(newimage<TheValue)))

[Niranjan]

ya the number of pixels is the same, I was wrong with the question . I mean to count the number of black pixels alone.

[Niranjan]

bar(avg(newimage<1)) when I use the above code I get a bar . But I need a bar with the number of black pixels on the y axis. Can you help?

This is what I am exactly in need of. Please have a look.

http://picasaweb.google.com/lh/photo/uzVPD9_OcmXMtPGw4m0jyJOzMXS1UfqXPDW9N1lFu0w?feat=directlink

[Walter Roberson]

In that case, simply

plot(sum(newimage<TheValue))

You have been asking for the *density* and to my mind, a *count* is not a density.

[Niranjan]

Thanks for your reply Roberson and can you tell me how to find the distance between the least two minimum positions in this plot?

[Niranjan]

Please have a look at this.Help me with this

http://picasaweb.google.com/lh/photo/4Rb9z8TNa1PcNO-Jjs3ydpOzMXS1UfqXPDW9N1lFu0w?feat=directlink

[Walter Roberson]

You don't need to plot to find that.

t = sum(newimage<TheValue);

[ts, tidx] = sort(t);

min2dist = abs(tidx(2) - tidx(1));

[Niranjan]

Thanks a lot :)

Answer 2

[Paulo Silva]

[X,map] = imread('trees.tif'); %example of an image
col=1:numel(X(1,:)); %create a column vector for the next code line 
Count(col)=sum(X(:,col)); %is this what you want?

[Niranjan]

bar(avg(newimage<1)) when I use the above code I get a bar . But I need a bar with the number of black pixels on the y axis. Can you help?

This is what I am exactly in need of. Please have a look.

http://picasaweb.google.com/lh/photo/uzVPD9_OcmXMtPGw4m0jyJOzMXS1UfqXPDW9N1lFu0w?feat=directlink

Answer 3

[JEBA CHRISTILDA]

Hi i want to create a graph for each blocks of binned image. it was an medical image can anybody please help me.

[Walter Roberson]

Please create a new Question for that.

In the new Question, describe what kind of graph you want to create, and indicate whether you need assistance with the dividing into blocks or only with the graphing.