How to extract latlon from the .TIFF file?

I have a LULC map as in .TIF/TIFF format, using its defined class in different colors I want to extract points (from another file which is shapefile) which lie over it.

I have used these two method/code but got error in each case:

1)

info = geotiffinfo('IGP_LULC.tif');

[x,y] = pix2map(info.RefMatrix, 1, 1);

[lat,lon] = projinv(info, x,y)

error in using projinv

2)

height = info.Height; % Integer indicating the height of the image in pixels

width = info.Width; % Integer indicating the width of the image in pixels

[rows,cols] = meshgrid(1:height,1:width);

% Getting the latitude and longitude of the points

[x,y] = pix2map(info.RefMatrix, rows, cols);

[lat,lon] = projinv(info, y,x);

error of memory