whats wrong with this code? i wanna zoom 2D image using nearest neighbor interpolation

function nearest_neighbor_zoom(file,fac)
im=imread(file);
[h,v,d]=size(im);
for i=1:h
    for j=1:v
    im1( floor(1+(i-1)*fac), floor(1+(j-1)*fac),:)=im(i,j,:); %mapping pixels of given image to a new array so that zooming factor is satisfied. 
    end  
end
[h1,v1,d]=size(im1);
disp('Unknown pixel values are being interpolated. Look at Figure1');
%nearest neighbor interpolation
for i=1:h1-1 
    for j=1:v1-1  

             if(  (floor( 1+(    ceil((i-1)/fac+1)    -1)*fac )==i)  && ( floor( 1+(    ceil((j-1)/fac+1)    -1)*fac )==j )  ) % maped values from the original picture should not be recalculated.     
             else  %for pixels that should be calculated    

             if(floor( 1+(    ceil((i-1)/fac+1)    -1)*fac )==i) %on a defined vertical level
                 xo00=ceil((i-1)/fac+1);
                 x00=i;
             else
                 xo00=floor((i-1)/fac+1); 
                 x00=floor(1+(xo00-1)*fac);
             end

             if( floor( 1+(    ceil((j-1)/fac+1)    -1)*fac )==j )%on a defined horizontal level
                 yo00=ceil((j-1)/fac+1);
                 y00=j;
             else
                 yo00=floor((j-1)/fac+1);
                 y00=floor(1+(yo00-1)*fac);
             end                  

            xo10=xo00+1;
            yo10=yo00;
            x10=floor(1+(xo10-1)*fac); %current coordinate of 10;
            y10=floor(1+(yo10-1)*fac);

            xo01=xo00;
            yo01=yo00+1;
            x01=floor(1+(xo01-1)*fac); %current coordinate of 01;
            y01=floor(1+(yo01-1)*fac);

            xo11=xo10;
            yo11=yo01;
            x11=x10; %current coordinate of 11;
            y11=y01;          

            xlen=x11-x00;
            ylen=y11-y00;

            x=i-x00;
            y=j-y00;

            dx=x/xlen; %converting coordinates of the pixel being calculated to (0*1)(0*1) domain.
            dy=y/ylen;          

             if dx<=0.5 %if the pixel being calculated is near to the known upper pixel level. 
                 nx=0; 
             else  %to known lower pixel level.
                 nx=1;
             end

             if dy<=0.5 %if the pixel being calculated is near to the known left pixel level.
             ny=0;
             else  %to known right pixel level.
             ny=1; 
             end  

             if ((nx==0) &&(ny==0)) %assigning the upper left known pixel to the pixel being calculated.
                 h00=im1(x00,y00,:);
                 im1(i,j,:)=h00;
             elseif ((nx==1) && (ny==0)) %assigning the lower left known pixel to the pixel being calculated.
                 h10=im1(x10,y10,:);
                 im1(i,j,:)=h10;
             elseif((nx==0) && (ny==1)) %assigning the upper right known pixel to the pixel being calculated.
                  h01=im1( x01,y01,:);
                 im1(i,j,:)=h01;
             elseif((nx==1)&&(ny==1)) %assigning the lower right known pixel to the pixel being calculated.
                 h11=im1(x11,y11,:);
                 im1(i,j,:)=h11;
             end
         end
      end
    imshow(im1); %displaying image being interpolated.
  end
  disp('Zooming is complet. Look at Figure1');
  imshow(im1);
  imwrite(im1,'zoomed_pic.jpg');

[Walter Roberson]

What leads you to suspect there is something wrong with the code? It looked okay when I tried it.

[Ali Purse]

it display this error

Answer 1

[madhan ravi]

file is the name of the file , you should call the function as such because your function requires two inputs , you can't simply press the green button to run without inputs defined

file ='example.jpg' %example

fac = 4 %example
function nearest_neighbor_zoom(file,fac)

please see common errors while calling function

[maryam yahyaie]

I try your suggestion and i got this: Error: File: Untitled2.m Line: 3 Column: 1 Function definitions are not permitted in this context.

[madhan ravi]

you should save the function file as nearest_neighbor_zoom.m and then you should try like my answer in a different file

[maryam yahyaie]

Nothing changed :( I tried it

[madhan ravi]

Show us how you are code again by attaching the file instead of code

[maryam yahyaie]

this is the original code

[madhan ravi]

Attaché the image file

[maryam yahyaie]

image file

[madhan ravi]

download both the files and run the COMMUNITY.m file delete your existing file nearest_neighbor_zoom.m

[madhan ravi]

it worked for me

[maryam yahyaie]

thank you so much. it worked

[madhan ravi]

Anytime :)