A method of binarizing a grayscale image comprising a border having top, bottom, left and right sides surrounding characters into a black and white binarized image, said method comprising: obtaining first and second binarized images of the grayscale image by dividing the grayscale image into sub-images for determining if a pixel is to be converted into white or black based on its colour value as compared to the average colour value of its sub-image, wherein one of the first and second binarized images is a black and white binarized border image comprising top, bottom, left and right borders and the other of the first and second binarized images is a black and white binarized characters image, wherein the binarized border image is obtained by using sub-images of a same first size for each pixel to be converted, and the binarized characters image is obtained by using sub-images of a same second size for each pixel to be converted, wherein said first size is larger than said second size; obtaining the height H and width W of the binarized border image; providing horizontal and vertical border density coefficients C h, and C v respectively; identifying in the binarized border image: the first pixel line ( B t) from the top in the top border having a line black density value that is less than Wx C h; the first pixel line ( B b) from the bottom in the bottom border having a line black density value that is less than Wx C h; the first pixel column (B l) from the left in the left border having a line black density value that is less than H x C v; the first pixel column ( B r) from the right in the right border having a line black density value that is less than H x C vi; thereby providing the border positions B f, B b, B l, and B r; mapping the found border contour on the binarized characters image; painting white the mapped border contour on the binarized characters image to obtain a binarized image without a border; and combining the binarized image without a border with the binarized border image so as to obtain the black and white binarized image. obtaining first and second binarized images of the grayscale image by dividing the grayscale image into sub-images for determining if a pixel is to be converted into white or black based on its colour value as compared to the average colour value of its sub-image, wherein one of the first and second binarized images is a black and white binarized border image comprising top, bottom, left and right borders and the other of the first and second binarized images is a black and white binarized characters image, wherein the binarized border image is obtained by using sub-images of a same first size for each pixel to be converted, and the binarized characters image is obtained by using sub-images of a same second size for each pixel to be converted, wherein said first size is larger than said second size; obtaining the height H and width W of the binarized border image; providing horizontal and vertical border density coefficients C h, and C v respectively; identifying in the binarized border image: the first pixel line ( B t) from the top in the top border having a line black density value that is less than Wx C h; the first pixel line ( B b) from the bottom in the bottom border having a line black density value that is less than Wx C h; the first pixel column (B l) from the left in the left border having a line black density value that is less than H x C v; the first pixel column ( B r) from the right in the right border having a line black density value that is less than H x C vi; the first pixel line ( B t) from the top in the top border having a line black density value that is less than Wx C h; the first pixel line ( B b) from the bottom in the bottom border having a line black density value that is less than Wx C h; the first pixel column (B l) from the left in the left border having a line black density value that is less than H x C v; the first pixel column ( B r) from the right in the right border having a line black density value that is less than H x C vi; thereby providing the border positions B f, B b, B l, and B r; mapping the found border contour on the binarized characters image; painting white the mapped border contour on the binarized characters image to obtain a binarized image without a border; and combining the binarized image without a border with the binarized border image so as to obtain the black and white binarized image.