Converting pixel coordinates to latitude and longitude in decimal degrees for a binary image.

How can I convert the centroid of the pixel coordinates into latitude and longitude values in decimal degrees ?I have used several functions like Utm2deg and utm2ll for doing the same after converting the pixels coordinates to UTM but it does not give any result.I am attaching the code here.It will be helpful if someone can help me with it as I am a novice in matlab.

A= geotiffread("img.tif');
r = regionprops('table',l,'centroid',);
x_centroid= r.Centroid;
y_centroid= r.Centroid;
R=makerefmat(885698,1258968,200,200);
[lat, lon] = pix2latlon(R,x_centroid,y_centroid);

Thanks in Adavance!

[darova]

You didn't attach the data/image

[darova]

How to display it? Is it the image?

I see nothing

[darova]

What are boudaries of images (lat/long)?

Maybe this data can be used for scaling?

    RasterExtentInWorldX: 20820
    RasterExtentInWorldY: 17790

[darova]

You want to scale your data?

[m,n,~] = size(A);            % size in pixels
xx = Left + (Right-Left)/n*x_centroid;        % worlds coordinates
yy = Bottom + (Top-Bottom)/m*y_centroid;

Answer 1

[darova]

You forgot about concantenating (cat) function

A= geotiffread('ems_a&n_subset.tif');

A(A>=0.99500)=0;
y = im2bw(A);
r = regionprops(y,'Centroid');
xy = cat(1,r.Centroid);

imshow(y)
hold on
plot(xy(:,1),xy(:,2),'or')
hold off

r.Centroid returns an asnwer as a structure not an array

>> r.Centroid
ans =
  163.5000  235.0000
ans =
  518.5882  368.7059

[darova]

What is connection between degrees and pixels?

[darova]

Did you try to express x and y?

lng = (x * radian - 135/180*pi) * earth_radius;  %[km]
x = 1/radian*(lng/earth_radius + 135/180*pi)
lat = atanh(sin(y)) * earth_radius;    %[km]
y = asin(tanh(lat/earth_radius))