How can I find the area of an irregular object in the image?

I used this code. But it doesn't separate the object from the image nor does it calculate the correct area of the image. ( I know this because i used the same image with smaller object, the area calculated was the same as before).

clc;
clear all;

input_im=imread('area2.png');
input_im=rgb2gray(input_im);

imshow(input_im)
title('Original Object')
sum_of_x_axis=sum(input_im,1);
sum_of_y_axis=sum(input_im,2);

location_of_object_on_x=find(sum_of_x_axis>0);

location_of_object_on_y=find(sum_of_y_axis>0);    

seperated_object=input_im(location_of_object_on_y(1):...
    location_of_object_on_y(end),location_of_object_on_x(1):...
    location_of_object_on_x(end));

figure;
imshow(seperated_object);
title('Seperated Object')

detected_outer_surface=im2bw(seperated_object);

sum_of_outer_space=0;

for i=1:size(seperated_object,1)
   if seperated_object(i,1)>0
       break
   end

      for j=1:size(seperated_object,2)
           if seperated_object(i,j)>0
          break
           end

           detected_outer_surface(i,j)=1;
           sum_of_outer_space=sum_of_outer_space+1;
      end
  end

for i=1:size(seperated_object,1)
   if seperated_object(i,size(seperated_object,2))>0
       break
   end

      for j=size(seperated_object,2):-1:1
           if seperated_object(i,j)>0
          break
           end

           detected_outer_surface(i,j)=1;
           sum_of_outer_space=sum_of_outer_space+1;
      end
  end

figure;

imshow(detected_outer_surface)

title('Detected outer Surface which does not belong to object')

Area_of_object=size(seperated_object,1)*size(seperated_object,2);

Area_of_object=Area_of_object-sum_of_outer_space

Height_of_the_line=max(sum_of_x_axis)

[KSSV]

Where is image?

[Ash]

sorry. here it is.