Activity 10: Preprocessing Handwritten Text

For this activity, the goal is to extract text from an imaged documents with lines. The given document is as follows (image resized):

I cropped a small portion of the image for faster calculations. The cropped image and its FT is shown below:
To remove the vertical and horizontal lines I applied the following filter and the image beside it is the resulting image, also included is the binarized version of the image:


It can be seen that the lines are not actually removed totally, specially at the edges. In the image we can see that only the 1st line column can be read and last column is totally unreadable. To further enhance the image I performed opening and closing to isolate some of the letters using a 2x1 structuring element. And to make the letters 1 pixel thick, I performed erosion using the same structuring element. Afterwards, I labeled the text using bwlabel, the following image is the result:


As expected only some of the text are readable, almost all of the the numbers on the 1st column and the fractions on the second column are readable, but the third to fifth columns are pretty much unreadable.
The whole scilab code I used is shown below, it is a "mixture" of my older codes so it may look familiar. =)
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I = imread("C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\small.bmp");
I2 = im2gray(I);
C = imread("C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\cross.bmp");
C = im2gray(C);
Cshift = fftshift(C);

ftI = fft2(I2);
conv = Cshift.*ftI;
iconv = fft2(conv);
iconv = abs(fft2(fft2(iconv)));
scf(0);imshow(I2,[]);
scf(1);imshow(iconv,[]);
imwrite(iconv/max(iconv), "C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\noLines.bmp");
imwrite(abs(fft2(fft2(iconv)))/max(abs(fft2(fft2(iconv)))), "C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\res.bmp");
bw = im2bw(iconv,0.5);
imwrite(bw, "C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\bw.bmp");
scf(3);imshow(bw,[]);

bw = abs(bw-1);
se = [1,1];



OC = erode(dilate(dilate(erode(bw,se),se),se),se);

OC = erode(OC,se);


L = bwlabel(OC);
scf(4);imshow(L,[]);

imwrite(L/max(L), "C:\Users\RAFAEL JACULBIA\Documents\subjects\186\activity10\last\labeled.bmp");
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For this activity, I will give myself a grade of 9/10 since I believe I was not able to accomplish the tasks perfectly. And for the first time I performed the activity without the help of others.