Tesseract engine does not work properly

edit

Hi all, I am trying to write a software to recognize some text from an image, but when I binarize the image and I call to tesseract engine, this does not recognize text in image. Does somebody know why text it is not recognized? Must I do something extra to recognize? I leave the image I am trying to recognize text. tesseract output is: "24"

I've also tried with another image like this:

And the output is also wrong. Output: "L I"

Could anybody help me?

Thanks in advance.