Preprocess an Image to remove Noise from the Background

Hello,

I have an image which contains a Text printed on it. I need to preprocess the image , remove all the noise in background and get a clear binary image for my further processing.

I have applied the following functions and obtained the prepossessed image.

i)Filt_Img=medfilt2(img ,[6 6])

ii)imsharpen(Filt_Img,'Radius',2.2,'Amount',5.6,'Threshold', 0.8);

iii)se = strel('square', 4);

im_close = imclose(b, se);

iv)Icorrected = imbothat(im_close, strel('disk', 20));

v)thresholded = thresholdLocally(Icorrected,[],'PadMethod','symmetric');

This function is obtained from the following link: http://in.mathworks.com/matlabcentral/fileexchange/29764-thresholdlocally/all_files

But i am not able to fully remove the noise in the background. If i try to clear the noise some portion of the text is removed.

I am sending here the Input Image, Preprossed image and the Threshold image. In the threshold image there is noise at the top near digit 4 and also the first character D is not fully seen. I need to remove that noise and still have the letter D obtained fully.

It would be great if you let me know what are functions to be used to get a clear image without noise.

Thanks

Pankaja